blob: 29d41003d6e0d2f57e625db58df115a5d18de487 [file] [log] [blame]
Thomas Gleixnerfd534e92019-05-23 11:14:39 +02001// SPDX-License-Identifier: GPL-2.0-or-later
Linus Torvalds1da177e2005-04-16 15:20:36 -07002/*
Linus Torvalds1da177e2005-04-16 15:20:36 -07003 * Core registration and callback routines for MTD
4 * drivers and users.
5 *
David Woodhousea1452a32010-08-08 20:58:20 +01006 * Copyright © 1999-2010 David Woodhouse <dwmw2@infradead.org>
7 * Copyright © 2006 Red Hat UK Limited
Linus Torvalds1da177e2005-04-16 15:20:36 -07008 */
9
Linus Torvalds1da177e2005-04-16 15:20:36 -070010#include <linux/module.h>
11#include <linux/kernel.h>
Linus Torvalds1da177e2005-04-16 15:20:36 -070012#include <linux/ptrace.h>
Alexey Dobriyan447d9bd2011-05-13 23:34:19 +030013#include <linux/seq_file.h>
Linus Torvalds1da177e2005-04-16 15:20:36 -070014#include <linux/string.h>
15#include <linux/timer.h>
16#include <linux/major.h>
17#include <linux/fs.h>
Artem Bityutskiy77993082006-10-11 14:52:44 +030018#include <linux/err.h>
Linus Torvalds1da177e2005-04-16 15:20:36 -070019#include <linux/ioctl.h>
20#include <linux/init.h>
Brian Norris215a02f2015-11-11 16:26:04 -080021#include <linux/of.h>
Linus Torvalds1da177e2005-04-16 15:20:36 -070022#include <linux/proc_fs.h>
Ben Hutchingsb520e412010-01-29 20:59:42 +000023#include <linux/idr.h>
Jörn Engela33eb6b2010-04-27 09:40:52 +020024#include <linux/backing-dev.h>
Tejun Heo05d71b462010-03-30 02:52:39 +090025#include <linux/gfp.h>
David Howells0d01ff22013-04-11 23:51:01 +010026#include <linux/slab.h>
Brian Norris3efe41b2014-11-26 01:01:08 -080027#include <linux/reboot.h>
Ezequiel Garciafea728c2016-04-12 17:46:42 -030028#include <linux/leds.h>
Mario Rugieroe8e3edb2017-05-29 08:38:41 -030029#include <linux/debugfs.h>
Alban Bedelc4dfa252018-11-13 15:01:10 +010030#include <linux/nvmem-provider.h>
Linus Torvalds1da177e2005-04-16 15:20:36 -070031
32#include <linux/mtd/mtd.h>
Jamie Ilesf5671ab2011-05-23 17:15:46 +010033#include <linux/mtd/partitions.h>
Linus Torvalds1da177e2005-04-16 15:20:36 -070034
Ben Dooks356d70f2007-05-28 20:28:34 +010035#include "mtdcore.h"
Artem Bityutskiy660685d2013-03-14 13:27:40 +020036
Jan Karafa060522017-04-12 12:24:37 +020037struct backing_dev_info *mtd_bdi;
Ben Dooks356d70f2007-05-28 20:28:34 +010038
Lars-Peter Clausen57b8045d2015-04-06 12:00:39 +020039#ifdef CONFIG_PM_SLEEP
40
41static int mtd_cls_suspend(struct device *dev)
42{
43 struct mtd_info *mtd = dev_get_drvdata(dev);
44
45 return mtd ? mtd_suspend(mtd) : 0;
46}
47
48static int mtd_cls_resume(struct device *dev)
49{
50 struct mtd_info *mtd = dev_get_drvdata(dev);
51
52 if (mtd)
53 mtd_resume(mtd);
54 return 0;
55}
56
57static SIMPLE_DEV_PM_OPS(mtd_cls_pm_ops, mtd_cls_suspend, mtd_cls_resume);
58#define MTD_CLS_PM_OPS (&mtd_cls_pm_ops)
59#else
60#define MTD_CLS_PM_OPS NULL
61#endif
David Brownell1f24b5a2009-03-26 00:42:41 -070062
David Woodhouse15bce402009-04-05 07:40:58 -070063static struct class mtd_class = {
64 .name = "mtd",
65 .owner = THIS_MODULE,
Lars-Peter Clausen57b8045d2015-04-06 12:00:39 +020066 .pm = MTD_CLS_PM_OPS,
David Woodhouse15bce402009-04-05 07:40:58 -070067};
David Brownell1f24b5a2009-03-26 00:42:41 -070068
Ben Hutchingsb520e412010-01-29 20:59:42 +000069static DEFINE_IDR(mtd_idr);
70
Thomas Gleixner97894cd2005-11-07 11:15:26 +000071/* These are exported solely for the purpose of mtd_blkdevs.c. You
Linus Torvalds1da177e2005-04-16 15:20:36 -070072 should not use them for _anything_ else */
Ingo Molnar48b19262006-03-31 02:29:41 -080073DEFINE_MUTEX(mtd_table_mutex);
Linus Torvalds1da177e2005-04-16 15:20:36 -070074EXPORT_SYMBOL_GPL(mtd_table_mutex);
Ben Hutchingsb520e412010-01-29 20:59:42 +000075
76struct mtd_info *__mtd_next_device(int i)
77{
78 return idr_get_next(&mtd_idr, &i);
79}
80EXPORT_SYMBOL_GPL(__mtd_next_device);
Linus Torvalds1da177e2005-04-16 15:20:36 -070081
82static LIST_HEAD(mtd_notifiers);
83
David Brownell1f24b5a2009-03-26 00:42:41 -070084
David Brownell1f24b5a2009-03-26 00:42:41 -070085#define MTD_DEVT(index) MKDEV(MTD_CHAR_MAJOR, (index)*2)
David Brownell1f24b5a2009-03-26 00:42:41 -070086
87/* REVISIT once MTD uses the driver model better, whoever allocates
88 * the mtd_info will probably want to use the release() hook...
89 */
90static void mtd_release(struct device *dev)
91{
Brian Norris5e472122014-07-21 19:06:47 -070092 struct mtd_info *mtd = dev_get_drvdata(dev);
Artem Bityutskiyd5de20a2011-12-29 18:00:29 +020093 dev_t index = MTD_DEVT(mtd->index);
David Brownell1f24b5a2009-03-26 00:42:41 -070094
Brian Norris5e472122014-07-21 19:06:47 -070095 /* remove /dev/mtdXro node */
96 device_destroy(&mtd_class, index + 1);
David Woodhouse15bce402009-04-05 07:40:58 -070097}
98
David Brownell1f24b5a2009-03-26 00:42:41 -070099static ssize_t mtd_type_show(struct device *dev,
100 struct device_attribute *attr, char *buf)
101{
Artem Bityutskiyd5de20a2011-12-29 18:00:29 +0200102 struct mtd_info *mtd = dev_get_drvdata(dev);
David Brownell1f24b5a2009-03-26 00:42:41 -0700103 char *type;
104
105 switch (mtd->type) {
106 case MTD_ABSENT:
107 type = "absent";
108 break;
109 case MTD_RAM:
110 type = "ram";
111 break;
112 case MTD_ROM:
113 type = "rom";
114 break;
115 case MTD_NORFLASH:
116 type = "nor";
117 break;
118 case MTD_NANDFLASH:
119 type = "nand";
120 break;
121 case MTD_DATAFLASH:
122 type = "dataflash";
123 break;
124 case MTD_UBIVOLUME:
125 type = "ubi";
126 break;
Huang Shijief4837242013-09-25 14:58:19 +0800127 case MTD_MLCNANDFLASH:
128 type = "mlc-nand";
129 break;
David Brownell1f24b5a2009-03-26 00:42:41 -0700130 default:
131 type = "unknown";
132 }
133
134 return snprintf(buf, PAGE_SIZE, "%s\n", type);
135}
Kevin Cernekee694bb7f2009-04-03 13:00:45 -0700136static DEVICE_ATTR(type, S_IRUGO, mtd_type_show, NULL);
137
138static ssize_t mtd_flags_show(struct device *dev,
139 struct device_attribute *attr, char *buf)
140{
Artem Bityutskiyd5de20a2011-12-29 18:00:29 +0200141 struct mtd_info *mtd = dev_get_drvdata(dev);
Kevin Cernekee694bb7f2009-04-03 13:00:45 -0700142
143 return snprintf(buf, PAGE_SIZE, "0x%lx\n", (unsigned long)mtd->flags);
Kevin Cernekee694bb7f2009-04-03 13:00:45 -0700144}
145static DEVICE_ATTR(flags, S_IRUGO, mtd_flags_show, NULL);
146
147static ssize_t mtd_size_show(struct device *dev,
148 struct device_attribute *attr, char *buf)
149{
Artem Bityutskiyd5de20a2011-12-29 18:00:29 +0200150 struct mtd_info *mtd = dev_get_drvdata(dev);
Kevin Cernekee694bb7f2009-04-03 13:00:45 -0700151
152 return snprintf(buf, PAGE_SIZE, "%llu\n",
153 (unsigned long long)mtd->size);
Kevin Cernekee694bb7f2009-04-03 13:00:45 -0700154}
155static DEVICE_ATTR(size, S_IRUGO, mtd_size_show, NULL);
156
157static ssize_t mtd_erasesize_show(struct device *dev,
158 struct device_attribute *attr, char *buf)
159{
Artem Bityutskiyd5de20a2011-12-29 18:00:29 +0200160 struct mtd_info *mtd = dev_get_drvdata(dev);
Kevin Cernekee694bb7f2009-04-03 13:00:45 -0700161
162 return snprintf(buf, PAGE_SIZE, "%lu\n", (unsigned long)mtd->erasesize);
Kevin Cernekee694bb7f2009-04-03 13:00:45 -0700163}
164static DEVICE_ATTR(erasesize, S_IRUGO, mtd_erasesize_show, NULL);
165
166static ssize_t mtd_writesize_show(struct device *dev,
167 struct device_attribute *attr, char *buf)
168{
Artem Bityutskiyd5de20a2011-12-29 18:00:29 +0200169 struct mtd_info *mtd = dev_get_drvdata(dev);
Kevin Cernekee694bb7f2009-04-03 13:00:45 -0700170
171 return snprintf(buf, PAGE_SIZE, "%lu\n", (unsigned long)mtd->writesize);
Kevin Cernekee694bb7f2009-04-03 13:00:45 -0700172}
173static DEVICE_ATTR(writesize, S_IRUGO, mtd_writesize_show, NULL);
174
Artem Bityutskiye7693542009-04-18 12:29:42 +0300175static ssize_t mtd_subpagesize_show(struct device *dev,
176 struct device_attribute *attr, char *buf)
177{
Artem Bityutskiyd5de20a2011-12-29 18:00:29 +0200178 struct mtd_info *mtd = dev_get_drvdata(dev);
Artem Bityutskiye7693542009-04-18 12:29:42 +0300179 unsigned int subpagesize = mtd->writesize >> mtd->subpage_sft;
180
181 return snprintf(buf, PAGE_SIZE, "%u\n", subpagesize);
Artem Bityutskiye7693542009-04-18 12:29:42 +0300182}
183static DEVICE_ATTR(subpagesize, S_IRUGO, mtd_subpagesize_show, NULL);
184
Kevin Cernekee694bb7f2009-04-03 13:00:45 -0700185static ssize_t mtd_oobsize_show(struct device *dev,
186 struct device_attribute *attr, char *buf)
187{
Artem Bityutskiyd5de20a2011-12-29 18:00:29 +0200188 struct mtd_info *mtd = dev_get_drvdata(dev);
Kevin Cernekee694bb7f2009-04-03 13:00:45 -0700189
190 return snprintf(buf, PAGE_SIZE, "%lu\n", (unsigned long)mtd->oobsize);
Kevin Cernekee694bb7f2009-04-03 13:00:45 -0700191}
192static DEVICE_ATTR(oobsize, S_IRUGO, mtd_oobsize_show, NULL);
193
Xiaolei Li7cc9aa62018-04-02 16:20:10 +0800194static ssize_t mtd_oobavail_show(struct device *dev,
195 struct device_attribute *attr, char *buf)
196{
197 struct mtd_info *mtd = dev_get_drvdata(dev);
198
199 return snprintf(buf, PAGE_SIZE, "%u\n", mtd->oobavail);
200}
201static DEVICE_ATTR(oobavail, S_IRUGO, mtd_oobavail_show, NULL);
202
Kevin Cernekee694bb7f2009-04-03 13:00:45 -0700203static ssize_t mtd_numeraseregions_show(struct device *dev,
204 struct device_attribute *attr, char *buf)
205{
Artem Bityutskiyd5de20a2011-12-29 18:00:29 +0200206 struct mtd_info *mtd = dev_get_drvdata(dev);
Kevin Cernekee694bb7f2009-04-03 13:00:45 -0700207
208 return snprintf(buf, PAGE_SIZE, "%u\n", mtd->numeraseregions);
Kevin Cernekee694bb7f2009-04-03 13:00:45 -0700209}
210static DEVICE_ATTR(numeraseregions, S_IRUGO, mtd_numeraseregions_show,
211 NULL);
212
213static ssize_t mtd_name_show(struct device *dev,
214 struct device_attribute *attr, char *buf)
215{
Artem Bityutskiyd5de20a2011-12-29 18:00:29 +0200216 struct mtd_info *mtd = dev_get_drvdata(dev);
Kevin Cernekee694bb7f2009-04-03 13:00:45 -0700217
218 return snprintf(buf, PAGE_SIZE, "%s\n", mtd->name);
Kevin Cernekee694bb7f2009-04-03 13:00:45 -0700219}
220static DEVICE_ATTR(name, S_IRUGO, mtd_name_show, NULL);
David Brownell1f24b5a2009-03-26 00:42:41 -0700221
Mike Dunna9b672e2012-04-25 12:06:07 -0700222static ssize_t mtd_ecc_strength_show(struct device *dev,
223 struct device_attribute *attr, char *buf)
224{
225 struct mtd_info *mtd = dev_get_drvdata(dev);
226
227 return snprintf(buf, PAGE_SIZE, "%u\n", mtd->ecc_strength);
228}
229static DEVICE_ATTR(ecc_strength, S_IRUGO, mtd_ecc_strength_show, NULL);
230
Mike Dunnd062d4e2012-04-25 12:06:08 -0700231static ssize_t mtd_bitflip_threshold_show(struct device *dev,
232 struct device_attribute *attr,
233 char *buf)
234{
235 struct mtd_info *mtd = dev_get_drvdata(dev);
236
237 return snprintf(buf, PAGE_SIZE, "%u\n", mtd->bitflip_threshold);
238}
239
240static ssize_t mtd_bitflip_threshold_store(struct device *dev,
241 struct device_attribute *attr,
242 const char *buf, size_t count)
243{
244 struct mtd_info *mtd = dev_get_drvdata(dev);
245 unsigned int bitflip_threshold;
246 int retval;
247
248 retval = kstrtouint(buf, 0, &bitflip_threshold);
249 if (retval)
250 return retval;
251
252 mtd->bitflip_threshold = bitflip_threshold;
253 return count;
254}
255static DEVICE_ATTR(bitflip_threshold, S_IRUGO | S_IWUSR,
256 mtd_bitflip_threshold_show,
257 mtd_bitflip_threshold_store);
258
Huang Shijiebf977e32013-08-16 10:10:05 +0800259static ssize_t mtd_ecc_step_size_show(struct device *dev,
260 struct device_attribute *attr, char *buf)
261{
262 struct mtd_info *mtd = dev_get_drvdata(dev);
263
264 return snprintf(buf, PAGE_SIZE, "%u\n", mtd->ecc_step_size);
265
266}
267static DEVICE_ATTR(ecc_step_size, S_IRUGO, mtd_ecc_step_size_show, NULL);
268
Ezequiel Garcia990a3af2014-06-24 10:55:50 -0300269static ssize_t mtd_ecc_stats_corrected_show(struct device *dev,
270 struct device_attribute *attr, char *buf)
271{
272 struct mtd_info *mtd = dev_get_drvdata(dev);
273 struct mtd_ecc_stats *ecc_stats = &mtd->ecc_stats;
274
275 return snprintf(buf, PAGE_SIZE, "%u\n", ecc_stats->corrected);
276}
277static DEVICE_ATTR(corrected_bits, S_IRUGO,
278 mtd_ecc_stats_corrected_show, NULL);
279
280static ssize_t mtd_ecc_stats_errors_show(struct device *dev,
281 struct device_attribute *attr, char *buf)
282{
283 struct mtd_info *mtd = dev_get_drvdata(dev);
284 struct mtd_ecc_stats *ecc_stats = &mtd->ecc_stats;
285
286 return snprintf(buf, PAGE_SIZE, "%u\n", ecc_stats->failed);
287}
288static DEVICE_ATTR(ecc_failures, S_IRUGO, mtd_ecc_stats_errors_show, NULL);
289
290static ssize_t mtd_badblocks_show(struct device *dev,
291 struct device_attribute *attr, char *buf)
292{
293 struct mtd_info *mtd = dev_get_drvdata(dev);
294 struct mtd_ecc_stats *ecc_stats = &mtd->ecc_stats;
295
296 return snprintf(buf, PAGE_SIZE, "%u\n", ecc_stats->badblocks);
297}
298static DEVICE_ATTR(bad_blocks, S_IRUGO, mtd_badblocks_show, NULL);
299
300static ssize_t mtd_bbtblocks_show(struct device *dev,
301 struct device_attribute *attr, char *buf)
302{
303 struct mtd_info *mtd = dev_get_drvdata(dev);
304 struct mtd_ecc_stats *ecc_stats = &mtd->ecc_stats;
305
306 return snprintf(buf, PAGE_SIZE, "%u\n", ecc_stats->bbtblocks);
307}
308static DEVICE_ATTR(bbt_blocks, S_IRUGO, mtd_bbtblocks_show, NULL);
309
David Brownell1f24b5a2009-03-26 00:42:41 -0700310static struct attribute *mtd_attrs[] = {
Kevin Cernekee694bb7f2009-04-03 13:00:45 -0700311 &dev_attr_type.attr,
312 &dev_attr_flags.attr,
313 &dev_attr_size.attr,
314 &dev_attr_erasesize.attr,
315 &dev_attr_writesize.attr,
Artem Bityutskiye7693542009-04-18 12:29:42 +0300316 &dev_attr_subpagesize.attr,
Kevin Cernekee694bb7f2009-04-03 13:00:45 -0700317 &dev_attr_oobsize.attr,
Xiaolei Li7cc9aa62018-04-02 16:20:10 +0800318 &dev_attr_oobavail.attr,
Kevin Cernekee694bb7f2009-04-03 13:00:45 -0700319 &dev_attr_numeraseregions.attr,
320 &dev_attr_name.attr,
Mike Dunna9b672e2012-04-25 12:06:07 -0700321 &dev_attr_ecc_strength.attr,
Huang Shijiebf977e32013-08-16 10:10:05 +0800322 &dev_attr_ecc_step_size.attr,
Ezequiel Garcia990a3af2014-06-24 10:55:50 -0300323 &dev_attr_corrected_bits.attr,
324 &dev_attr_ecc_failures.attr,
325 &dev_attr_bad_blocks.attr,
326 &dev_attr_bbt_blocks.attr,
Mike Dunnd062d4e2012-04-25 12:06:08 -0700327 &dev_attr_bitflip_threshold.attr,
David Brownell1f24b5a2009-03-26 00:42:41 -0700328 NULL,
329};
Axel Lin54c738f2013-12-02 10:12:25 +0800330ATTRIBUTE_GROUPS(mtd);
David Brownell1f24b5a2009-03-26 00:42:41 -0700331
Bhumika Goyal75864b32017-08-19 13:52:17 +0530332static const struct device_type mtd_devtype = {
David Brownell1f24b5a2009-03-26 00:42:41 -0700333 .name = "mtd",
334 .groups = mtd_groups,
335 .release = mtd_release,
336};
337
Zhuohao Lee1018c942019-07-01 00:07:10 +0800338static int mtd_partid_show(struct seq_file *s, void *p)
339{
340 struct mtd_info *mtd = s->private;
341
342 seq_printf(s, "%s\n", mtd->dbg.partid);
343
344 return 0;
345}
346
347static int mtd_partid_debugfs_open(struct inode *inode, struct file *file)
348{
349 return single_open(file, mtd_partid_show, inode->i_private);
350}
351
352static const struct file_operations mtd_partid_debug_fops = {
353 .open = mtd_partid_debugfs_open,
354 .read = seq_read,
355 .llseek = seq_lseek,
356 .release = single_release,
357};
358
359static int mtd_partname_show(struct seq_file *s, void *p)
360{
361 struct mtd_info *mtd = s->private;
362
363 seq_printf(s, "%s\n", mtd->dbg.partname);
364
365 return 0;
366}
367
368static int mtd_partname_debugfs_open(struct inode *inode, struct file *file)
369{
370 return single_open(file, mtd_partname_show, inode->i_private);
371}
372
373static const struct file_operations mtd_partname_debug_fops = {
374 .open = mtd_partname_debugfs_open,
375 .read = seq_read,
376 .llseek = seq_lseek,
377 .release = single_release,
378};
379
380static struct dentry *dfs_dir_mtd;
381
382static void mtd_debugfs_populate(struct mtd_info *mtd)
383{
384 struct device *dev = &mtd->dev;
Greg Kroah-Hartmanc2d73ba2019-11-07 09:51:11 +0100385 struct dentry *root;
Zhuohao Lee1018c942019-07-01 00:07:10 +0800386
387 if (IS_ERR_OR_NULL(dfs_dir_mtd))
388 return;
389
390 root = debugfs_create_dir(dev_name(dev), dfs_dir_mtd);
Zhuohao Lee1018c942019-07-01 00:07:10 +0800391 mtd->dbg.dfs_dir = root;
392
Greg Kroah-Hartmanc2d73ba2019-11-07 09:51:11 +0100393 if (mtd->dbg.partid)
394 debugfs_create_file("partid", 0400, root, mtd,
395 &mtd_partid_debug_fops);
Zhuohao Lee1018c942019-07-01 00:07:10 +0800396
Greg Kroah-Hartmanc2d73ba2019-11-07 09:51:11 +0100397 if (mtd->dbg.partname)
398 debugfs_create_file("partname", 0400, root, mtd,
399 &mtd_partname_debug_fops);
Zhuohao Lee1018c942019-07-01 00:07:10 +0800400}
401
Christoph Hellwigb4caecd2015-01-14 10:42:32 +0100402#ifndef CONFIG_MMU
403unsigned mtd_mmap_capabilities(struct mtd_info *mtd)
404{
405 switch (mtd->type) {
406 case MTD_RAM:
407 return NOMMU_MAP_COPY | NOMMU_MAP_DIRECT | NOMMU_MAP_EXEC |
408 NOMMU_MAP_READ | NOMMU_MAP_WRITE;
409 case MTD_ROM:
410 return NOMMU_MAP_COPY | NOMMU_MAP_DIRECT | NOMMU_MAP_EXEC |
411 NOMMU_MAP_READ;
412 default:
413 return NOMMU_MAP_COPY;
414 }
415}
Arnd Bergmann706a4e52015-01-28 11:09:20 -0700416EXPORT_SYMBOL_GPL(mtd_mmap_capabilities);
Christoph Hellwigb4caecd2015-01-14 10:42:32 +0100417#endif
418
Brian Norris3efe41b2014-11-26 01:01:08 -0800419static int mtd_reboot_notifier(struct notifier_block *n, unsigned long state,
420 void *cmd)
421{
422 struct mtd_info *mtd;
423
424 mtd = container_of(n, struct mtd_info, reboot_notifier);
425 mtd->_reboot(mtd);
426
427 return NOTIFY_DONE;
428}
429
Linus Torvalds1da177e2005-04-16 15:20:36 -0700430/**
Boris Brezillon477b0222015-11-16 15:53:13 +0100431 * mtd_wunit_to_pairing_info - get pairing information of a wunit
432 * @mtd: pointer to new MTD device info structure
433 * @wunit: write unit we are interested in
434 * @info: returned pairing information
435 *
436 * Retrieve pairing information associated to the wunit.
437 * This is mainly useful when dealing with MLC/TLC NANDs where pages can be
438 * paired together, and where programming a page may influence the page it is
439 * paired with.
440 * The notion of page is replaced by the term wunit (write-unit) to stay
441 * consistent with the ->writesize field.
442 *
443 * The @wunit argument can be extracted from an absolute offset using
444 * mtd_offset_to_wunit(). @info is filled with the pairing information attached
445 * to @wunit.
446 *
447 * From the pairing info the MTD user can find all the wunits paired with
448 * @wunit using the following loop:
449 *
450 * for (i = 0; i < mtd_pairing_groups(mtd); i++) {
451 * info.pair = i;
452 * mtd_pairing_info_to_wunit(mtd, &info);
453 * ...
454 * }
455 */
456int mtd_wunit_to_pairing_info(struct mtd_info *mtd, int wunit,
457 struct mtd_pairing_info *info)
458{
Miquel Raynal46b58892020-01-14 10:09:52 +0100459 struct mtd_info *master = mtd_get_master(mtd);
460 int npairs = mtd_wunit_per_eb(master) / mtd_pairing_groups(master);
Boris Brezillon477b0222015-11-16 15:53:13 +0100461
462 if (wunit < 0 || wunit >= npairs)
463 return -EINVAL;
464
Miquel Raynal46b58892020-01-14 10:09:52 +0100465 if (master->pairing && master->pairing->get_info)
466 return master->pairing->get_info(master, wunit, info);
Boris Brezillon477b0222015-11-16 15:53:13 +0100467
468 info->group = 0;
469 info->pair = wunit;
470
471 return 0;
472}
473EXPORT_SYMBOL_GPL(mtd_wunit_to_pairing_info);
474
475/**
Xiaolei Lic77a9312018-03-29 09:34:58 +0800476 * mtd_pairing_info_to_wunit - get wunit from pairing information
Boris Brezillon477b0222015-11-16 15:53:13 +0100477 * @mtd: pointer to new MTD device info structure
478 * @info: pairing information struct
479 *
480 * Returns a positive number representing the wunit associated to the info
481 * struct, or a negative error code.
482 *
483 * This is the reverse of mtd_wunit_to_pairing_info(), and can help one to
484 * iterate over all wunits of a given pair (see mtd_wunit_to_pairing_info()
485 * doc).
486 *
487 * It can also be used to only program the first page of each pair (i.e.
488 * page attached to group 0), which allows one to use an MLC NAND in
489 * software-emulated SLC mode:
490 *
491 * info.group = 0;
492 * npairs = mtd_wunit_per_eb(mtd) / mtd_pairing_groups(mtd);
493 * for (info.pair = 0; info.pair < npairs; info.pair++) {
494 * wunit = mtd_pairing_info_to_wunit(mtd, &info);
495 * mtd_write(mtd, mtd_wunit_to_offset(mtd, blkoffs, wunit),
496 * mtd->writesize, &retlen, buf + (i * mtd->writesize));
497 * }
498 */
499int mtd_pairing_info_to_wunit(struct mtd_info *mtd,
500 const struct mtd_pairing_info *info)
501{
Miquel Raynal46b58892020-01-14 10:09:52 +0100502 struct mtd_info *master = mtd_get_master(mtd);
503 int ngroups = mtd_pairing_groups(master);
504 int npairs = mtd_wunit_per_eb(master) / ngroups;
Boris Brezillon477b0222015-11-16 15:53:13 +0100505
506 if (!info || info->pair < 0 || info->pair >= npairs ||
507 info->group < 0 || info->group >= ngroups)
508 return -EINVAL;
509
Miquel Raynal46b58892020-01-14 10:09:52 +0100510 if (master->pairing && master->pairing->get_wunit)
511 return mtd->pairing->get_wunit(master, info);
Boris Brezillon477b0222015-11-16 15:53:13 +0100512
513 return info->pair;
514}
515EXPORT_SYMBOL_GPL(mtd_pairing_info_to_wunit);
516
517/**
518 * mtd_pairing_groups - get the number of pairing groups
519 * @mtd: pointer to new MTD device info structure
520 *
521 * Returns the number of pairing groups.
522 *
523 * This number is usually equal to the number of bits exposed by a single
524 * cell, and can be used in conjunction with mtd_pairing_info_to_wunit()
525 * to iterate over all pages of a given pair.
526 */
527int mtd_pairing_groups(struct mtd_info *mtd)
528{
Miquel Raynal46b58892020-01-14 10:09:52 +0100529 struct mtd_info *master = mtd_get_master(mtd);
530
531 if (!master->pairing || !master->pairing->ngroups)
Boris Brezillon477b0222015-11-16 15:53:13 +0100532 return 1;
533
Miquel Raynal46b58892020-01-14 10:09:52 +0100534 return master->pairing->ngroups;
Boris Brezillon477b0222015-11-16 15:53:13 +0100535}
536EXPORT_SYMBOL_GPL(mtd_pairing_groups);
537
Alban Bedelc4dfa252018-11-13 15:01:10 +0100538static int mtd_nvmem_reg_read(void *priv, unsigned int offset,
539 void *val, size_t bytes)
540{
541 struct mtd_info *mtd = priv;
542 size_t retlen;
543 int err;
544
545 err = mtd_read(mtd, offset, bytes, &retlen, val);
546 if (err && err != -EUCLEAN)
547 return err;
548
549 return retlen == bytes ? 0 : -EIO;
550}
551
552static int mtd_nvmem_add(struct mtd_info *mtd)
553{
554 struct nvmem_config config = {};
555
Aneesh Kumar K.V6e952682019-02-11 19:03:37 +0530556 config.id = -1;
Alban Bedelc4dfa252018-11-13 15:01:10 +0100557 config.dev = &mtd->dev;
Ricardo Ribalda Delgado7b01b722020-04-30 15:17:21 +0200558 config.name = dev_name(&mtd->dev);
Alban Bedelc4dfa252018-11-13 15:01:10 +0100559 config.owner = THIS_MODULE;
560 config.reg_read = mtd_nvmem_reg_read;
561 config.size = mtd->size;
562 config.word_size = 1;
563 config.stride = 1;
564 config.read_only = true;
565 config.root_only = true;
566 config.no_of_node = true;
567 config.priv = mtd;
568
569 mtd->nvmem = nvmem_register(&config);
570 if (IS_ERR(mtd->nvmem)) {
571 /* Just ignore if there is no NVMEM support in the kernel */
Boris Brezillon19e16fb2019-01-02 15:36:53 +0100572 if (PTR_ERR(mtd->nvmem) == -EOPNOTSUPP) {
Alban Bedelc4dfa252018-11-13 15:01:10 +0100573 mtd->nvmem = NULL;
574 } else {
575 dev_err(&mtd->dev, "Failed to register NVMEM device\n");
576 return PTR_ERR(mtd->nvmem);
577 }
578 }
579
580 return 0;
581}
582
Boris Brezillon477b0222015-11-16 15:53:13 +0100583/**
Linus Torvalds1da177e2005-04-16 15:20:36 -0700584 * add_mtd_device - register an MTD device
585 * @mtd: pointer to new MTD device info structure
586 *
587 * Add a device to the list of MTD devices present in the system, and
588 * notify each currently active MTD 'user' of its arrival. Returns
Brian Norris57dd9902015-06-01 16:17:18 -0700589 * zero on success or non-zero on failure.
Linus Torvalds1da177e2005-04-16 15:20:36 -0700590 */
591
592int add_mtd_device(struct mtd_info *mtd)
593{
Miquel Raynal46b58892020-01-14 10:09:52 +0100594 struct mtd_info *master = mtd_get_master(mtd);
Ben Hutchingsb520e412010-01-29 20:59:42 +0000595 struct mtd_notifier *not;
596 int i, error;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700597
Brian Norrisbe0dbff2015-06-01 16:17:20 -0700598 /*
599 * May occur, for instance, on buggy drivers which call
600 * mtd_device_parse_register() multiple times on the same master MTD,
601 * especially with CONFIG_MTD_PARTITIONED_MASTER=y.
602 */
Jan Karafa060522017-04-12 12:24:37 +0200603 if (WARN_ONCE(mtd->dev.type, "MTD already registered\n"))
Brian Norrisbe0dbff2015-06-01 16:17:20 -0700604 return -EEXIST;
605
Artem B. Bityutskiy783ed812006-06-14 19:53:44 +0400606 BUG_ON(mtd->writesize == 0);
Boris Brezillon33f45c42017-12-15 13:39:51 +0100607
Boris Brezillon2431c4f2018-12-20 15:13:20 +0100608 /*
609 * MTD drivers should implement ->_{write,read}() or
610 * ->_{write,read}_oob(), but not both.
611 */
612 if (WARN_ON((mtd->_write && mtd->_write_oob) ||
613 (mtd->_read && mtd->_read_oob)))
614 return -EINVAL;
615
Miquel Raynal46b58892020-01-14 10:09:52 +0100616 if (WARN_ON((!mtd->erasesize || !master->_erase) &&
Boris Brezillon33f45c42017-12-15 13:39:51 +0100617 !(mtd->flags & MTD_NO_ERASE)))
618 return -EINVAL;
619
Ingo Molnar48b19262006-03-31 02:29:41 -0800620 mutex_lock(&mtd_table_mutex);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700621
Tejun Heo589e9c42013-02-27 17:04:33 -0800622 i = idr_alloc(&mtd_idr, mtd, 0, 0, GFP_KERNEL);
Brian Norris57dd9902015-06-01 16:17:18 -0700623 if (i < 0) {
624 error = i;
Ben Hutchingsb520e412010-01-29 20:59:42 +0000625 goto fail_locked;
Brian Norris57dd9902015-06-01 16:17:18 -0700626 }
Linus Torvalds1da177e2005-04-16 15:20:36 -0700627
Ben Hutchingsb520e412010-01-29 20:59:42 +0000628 mtd->index = i;
629 mtd->usecount = 0;
Adrian Hunter69423d92008-12-10 13:37:21 +0000630
Mike Dunnd062d4e2012-04-25 12:06:08 -0700631 /* default value if not set by driver */
632 if (mtd->bitflip_threshold == 0)
633 mtd->bitflip_threshold = mtd->ecc_strength;
634
Ben Hutchingsb520e412010-01-29 20:59:42 +0000635 if (is_power_of_2(mtd->erasesize))
636 mtd->erasesize_shift = ffs(mtd->erasesize) - 1;
637 else
638 mtd->erasesize_shift = 0;
Adrian Hunter69423d92008-12-10 13:37:21 +0000639
Ben Hutchingsb520e412010-01-29 20:59:42 +0000640 if (is_power_of_2(mtd->writesize))
641 mtd->writesize_shift = ffs(mtd->writesize) - 1;
642 else
643 mtd->writesize_shift = 0;
Adrian Hunter69423d92008-12-10 13:37:21 +0000644
Ben Hutchingsb520e412010-01-29 20:59:42 +0000645 mtd->erasesize_mask = (1 << mtd->erasesize_shift) - 1;
646 mtd->writesize_mask = (1 << mtd->writesize_shift) - 1;
Håvard Skinnemoen187ef152006-09-22 10:07:08 +0100647
Ben Hutchingsb520e412010-01-29 20:59:42 +0000648 /* Some chips always power up locked. Unlock them now */
Artem Bityutskiy38134562011-12-30 17:00:35 +0200649 if ((mtd->flags & MTD_WRITEABLE) && (mtd->flags & MTD_POWERUP_LOCK)) {
650 error = mtd_unlock(mtd, 0, mtd->size);
651 if (error && error != -EOPNOTSUPP)
Ben Hutchingsb520e412010-01-29 20:59:42 +0000652 printk(KERN_WARNING
653 "%s: unlock failed, writes may not work\n",
654 mtd->name);
Brian Norris57dd9902015-06-01 16:17:18 -0700655 /* Ignore unlock failures? */
656 error = 0;
Ben Hutchingsb520e412010-01-29 20:59:42 +0000657 }
David Brownell1f24b5a2009-03-26 00:42:41 -0700658
Ben Hutchingsb520e412010-01-29 20:59:42 +0000659 /* Caller should have set dev.parent to match the
Frans Klaver260e89a2015-06-10 22:38:15 +0200660 * physical device, if appropriate.
Ben Hutchingsb520e412010-01-29 20:59:42 +0000661 */
662 mtd->dev.type = &mtd_devtype;
663 mtd->dev.class = &mtd_class;
664 mtd->dev.devt = MTD_DEVT(i);
665 dev_set_name(&mtd->dev, "mtd%d", i);
666 dev_set_drvdata(&mtd->dev, mtd);
Brian Norris215a02f2015-11-11 16:26:04 -0800667 of_node_get(mtd_get_of_node(mtd));
Brian Norris57dd9902015-06-01 16:17:18 -0700668 error = device_register(&mtd->dev);
669 if (error)
Ben Hutchingsb520e412010-01-29 20:59:42 +0000670 goto fail_added;
David Brownell1f24b5a2009-03-26 00:42:41 -0700671
Alban Bedelc4dfa252018-11-13 15:01:10 +0100672 /* Add the nvmem provider */
673 error = mtd_nvmem_add(mtd);
674 if (error)
675 goto fail_nvmem_add;
676
Zhuohao Lee1018c942019-07-01 00:07:10 +0800677 mtd_debugfs_populate(mtd);
Mario Rugieroe8e3edb2017-05-29 08:38:41 -0300678
Brian Norris5e472122014-07-21 19:06:47 -0700679 device_create(&mtd_class, mtd->dev.parent, MTD_DEVT(i) + 1, NULL,
680 "mtd%dro", i);
Thomas Gleixner97894cd2005-11-07 11:15:26 +0000681
Brian Norris289c0522011-07-19 10:06:09 -0700682 pr_debug("mtd: Giving out device %d to %s\n", i, mtd->name);
Ben Hutchingsb520e412010-01-29 20:59:42 +0000683 /* No need to get a refcount on the module containing
684 the notifier, since we hold the mtd_table_mutex */
685 list_for_each_entry(not, &mtd_notifiers, list)
686 not->add(mtd);
Thomas Gleixner97894cd2005-11-07 11:15:26 +0000687
Ingo Molnar48b19262006-03-31 02:29:41 -0800688 mutex_unlock(&mtd_table_mutex);
Ben Hutchingsb520e412010-01-29 20:59:42 +0000689 /* We _know_ we aren't being removed, because
690 our caller is still holding us here. So none
691 of this try_ nonsense, and no bitching about it
692 either. :) */
693 __module_get(THIS_MODULE);
694 return 0;
695
Alban Bedelc4dfa252018-11-13 15:01:10 +0100696fail_nvmem_add:
697 device_unregister(&mtd->dev);
Ben Hutchingsb520e412010-01-29 20:59:42 +0000698fail_added:
Brian Norris215a02f2015-11-11 16:26:04 -0800699 of_node_put(mtd_get_of_node(mtd));
Ben Hutchingsb520e412010-01-29 20:59:42 +0000700 idr_remove(&mtd_idr, i);
701fail_locked:
702 mutex_unlock(&mtd_table_mutex);
Brian Norris57dd9902015-06-01 16:17:18 -0700703 return error;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700704}
705
706/**
707 * del_mtd_device - unregister an MTD device
708 * @mtd: pointer to MTD device info structure
709 *
710 * Remove a device from the list of MTD devices present in the system,
711 * and notify each currently active MTD 'user' of its departure.
712 * Returns zero on success or 1 on failure, which currently will happen
713 * if the requested device does not appear to be present in the list.
714 */
715
Jamie Ileseea72d52011-05-23 10:23:42 +0100716int del_mtd_device(struct mtd_info *mtd)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700717{
718 int ret;
Maxim Levitsky75c0b842010-02-22 20:39:32 +0200719 struct mtd_notifier *not;
Thomas Gleixner97894cd2005-11-07 11:15:26 +0000720
Ingo Molnar48b19262006-03-31 02:29:41 -0800721 mutex_lock(&mtd_table_mutex);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700722
Mario Rugieroe8e3edb2017-05-29 08:38:41 -0300723 debugfs_remove_recursive(mtd->dbg.dfs_dir);
724
Ben Hutchingsb520e412010-01-29 20:59:42 +0000725 if (idr_find(&mtd_idr, mtd->index) != mtd) {
Linus Torvalds1da177e2005-04-16 15:20:36 -0700726 ret = -ENODEV;
Maxim Levitsky75c0b842010-02-22 20:39:32 +0200727 goto out_error;
728 }
729
730 /* No need to get a refcount on the module containing
731 the notifier, since we hold the mtd_table_mutex */
732 list_for_each_entry(not, &mtd_notifiers, list)
733 not->remove(mtd);
734
735 if (mtd->usecount) {
Thomas Gleixner97894cd2005-11-07 11:15:26 +0000736 printk(KERN_NOTICE "Removing MTD device #%d (%s) with use count %d\n",
Linus Torvalds1da177e2005-04-16 15:20:36 -0700737 mtd->index, mtd->name, mtd->usecount);
738 ret = -EBUSY;
739 } else {
Alban Bedelc4dfa252018-11-13 15:01:10 +0100740 /* Try to remove the NVMEM provider */
741 if (mtd->nvmem)
742 nvmem_unregister(mtd->nvmem);
743
Kevin Cernekee694bb7f2009-04-03 13:00:45 -0700744 device_unregister(&mtd->dev);
745
Ben Hutchingsb520e412010-01-29 20:59:42 +0000746 idr_remove(&mtd_idr, mtd->index);
Brian Norris215a02f2015-11-11 16:26:04 -0800747 of_node_put(mtd_get_of_node(mtd));
Linus Torvalds1da177e2005-04-16 15:20:36 -0700748
749 module_put(THIS_MODULE);
750 ret = 0;
751 }
752
Maxim Levitsky75c0b842010-02-22 20:39:32 +0200753out_error:
Ingo Molnar48b19262006-03-31 02:29:41 -0800754 mutex_unlock(&mtd_table_mutex);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700755 return ret;
756}
757
Brian Norris472b4442015-12-11 15:58:01 -0800758/*
759 * Set a few defaults based on the parent devices, if not provided by the
760 * driver
761 */
762static void mtd_set_dev_defaults(struct mtd_info *mtd)
763{
764 if (mtd->dev.parent) {
765 if (!mtd->owner && mtd->dev.parent->driver)
766 mtd->owner = mtd->dev.parent->driver->owner;
767 if (!mtd->name)
768 mtd->name = dev_name(mtd->dev.parent);
769 } else {
770 pr_debug("mtd device won't show a device symlink in sysfs\n");
771 }
Rafał Miłecki1186af42018-11-20 09:55:45 +0100772
Miquel Raynal46b58892020-01-14 10:09:52 +0100773 INIT_LIST_HEAD(&mtd->partitions);
774 mutex_init(&mtd->master.partitions_lock);
Brian Norris472b4442015-12-11 15:58:01 -0800775}
Dan Ehrenberg727dc612015-04-02 15:15:10 -0700776
Linus Torvalds1da177e2005-04-16 15:20:36 -0700777/**
Dmitry Eremin-Solenikov1c4c2152011-03-25 22:26:25 +0300778 * mtd_device_parse_register - parse partitions and register an MTD device.
779 *
780 * @mtd: the MTD device to register
781 * @types: the list of MTD partition probes to try, see
782 * 'parse_mtd_partitions()' for more information
Dmitry Eremin-Solenikovc7975332011-06-10 18:18:28 +0400783 * @parser_data: MTD partition parser-specific data
Dmitry Eremin-Solenikov1c4c2152011-03-25 22:26:25 +0300784 * @parts: fallback partition information to register, if parsing fails;
785 * only valid if %nr_parts > %0
786 * @nr_parts: the number of partitions in parts, if zero then the full
787 * MTD device is registered if no partition info is found
788 *
789 * This function aggregates MTD partitions parsing (done by
790 * 'parse_mtd_partitions()') and MTD device and partitions registering. It
791 * basically follows the most common pattern found in many MTD drivers:
792 *
Rafał Miłecki55a999a2018-03-27 15:36:47 +0200793 * * If the MTD_PARTITIONED_MASTER option is set, then the device as a whole is
794 * registered first.
795 * * Then It tries to probe partitions on MTD device @mtd using parsers
Dmitry Eremin-Solenikov1c4c2152011-03-25 22:26:25 +0300796 * specified in @types (if @types is %NULL, then the default list of parsers
797 * is used, see 'parse_mtd_partitions()' for more information). If none are
798 * found this functions tries to fallback to information specified in
799 * @parts/@nr_parts.
Dmitry Eremin-Solenikov1c4c2152011-03-25 22:26:25 +0300800 * * If no partitions were found this function just registers the MTD device
801 * @mtd and exits.
802 *
803 * Returns zero in case of success and a negative error code in case of failure.
804 */
Artem Bityutskiy26a47342013-03-11 15:38:48 +0200805int mtd_device_parse_register(struct mtd_info *mtd, const char * const *types,
Dmitry Eremin-Solenikovc7975332011-06-10 18:18:28 +0400806 struct mtd_part_parser_data *parser_data,
Dmitry Eremin-Solenikov1c4c2152011-03-25 22:26:25 +0300807 const struct mtd_partition *parts,
808 int nr_parts)
809{
Dan Ehrenberg727dc612015-04-02 15:15:10 -0700810 int ret;
Dmitry Eremin-Solenikov1c4c2152011-03-25 22:26:25 +0300811
Brian Norris472b4442015-12-11 15:58:01 -0800812 mtd_set_dev_defaults(mtd);
813
Rafał Miłecki2c77c572018-01-16 16:45:41 +0100814 if (IS_ENABLED(CONFIG_MTD_PARTITIONED_MASTER)) {
815 ret = add_mtd_device(mtd);
816 if (ret)
817 return ret;
818 }
819
Rafał Miłecki0dbe4ea2018-01-16 16:45:42 +0100820 /* Prefer parsed partitions over driver-provided fallback */
Rafał Miłecki5ac67ce2018-03-27 22:35:41 +0200821 ret = parse_mtd_partitions(mtd, types, parser_data);
822 if (ret > 0)
823 ret = 0;
824 else if (nr_parts)
Rafał Miłecki0dbe4ea2018-01-16 16:45:42 +0100825 ret = add_mtd_partitions(mtd, parts, nr_parts);
826 else if (!device_is_registered(&mtd->dev))
827 ret = add_mtd_device(mtd);
828 else
829 ret = 0;
830
Brian Norris3e00ed02015-06-01 16:17:19 -0700831 if (ret)
832 goto out;
Dmitry Eremin-Solenikov1c4c2152011-03-25 22:26:25 +0300833
Niklas Cassele1dd8642015-02-01 02:08:50 +0100834 /*
835 * FIXME: some drivers unfortunately call this function more than once.
836 * So we have to check if we've already assigned the reboot notifier.
837 *
838 * Generally, we can make multiple calls work for most cases, but it
839 * does cause problems with parse_mtd_partitions() above (e.g.,
840 * cmdlineparts will register partitions more than once).
841 */
Brian Norrisf8479dd2015-11-03 17:01:53 -0800842 WARN_ONCE(mtd->_reboot && mtd->reboot_notifier.notifier_call,
843 "MTD already registered\n");
Niklas Cassele1dd8642015-02-01 02:08:50 +0100844 if (mtd->_reboot && !mtd->reboot_notifier.notifier_call) {
Brian Norris3efe41b2014-11-26 01:01:08 -0800845 mtd->reboot_notifier.notifier_call = mtd_reboot_notifier;
846 register_reboot_notifier(&mtd->reboot_notifier);
847 }
848
Brian Norris3e00ed02015-06-01 16:17:19 -0700849out:
Rafał Miłecki2c77c572018-01-16 16:45:41 +0100850 if (ret && device_is_registered(&mtd->dev))
851 del_mtd_device(mtd);
852
Dan Ehrenberg727dc612015-04-02 15:15:10 -0700853 return ret;
Dmitry Eremin-Solenikov1c4c2152011-03-25 22:26:25 +0300854}
855EXPORT_SYMBOL_GPL(mtd_device_parse_register);
856
857/**
Jamie Ilesf5671ab2011-05-23 17:15:46 +0100858 * mtd_device_unregister - unregister an existing MTD device.
859 *
860 * @master: the MTD device to unregister. This will unregister both the master
861 * and any partitions if registered.
862 */
863int mtd_device_unregister(struct mtd_info *master)
864{
865 int err;
866
Brian Norris3efe41b2014-11-26 01:01:08 -0800867 if (master->_reboot)
868 unregister_reboot_notifier(&master->reboot_notifier);
869
Jamie Ilesf5671ab2011-05-23 17:15:46 +0100870 err = del_mtd_partitions(master);
871 if (err)
872 return err;
873
874 if (!device_is_registered(&master->dev))
875 return 0;
876
877 return del_mtd_device(master);
878}
879EXPORT_SYMBOL_GPL(mtd_device_unregister);
880
881/**
Linus Torvalds1da177e2005-04-16 15:20:36 -0700882 * register_mtd_user - register a 'user' of MTD devices.
883 * @new: pointer to notifier info structure
884 *
885 * Registers a pair of callbacks function to be called upon addition
886 * or removal of MTD devices. Causes the 'add' callback to be immediately
887 * invoked for each MTD device currently present in the system.
888 */
Linus Torvalds1da177e2005-04-16 15:20:36 -0700889void register_mtd_user (struct mtd_notifier *new)
890{
Ben Hutchingsf1332ba2010-01-29 20:57:11 +0000891 struct mtd_info *mtd;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700892
Ingo Molnar48b19262006-03-31 02:29:41 -0800893 mutex_lock(&mtd_table_mutex);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700894
895 list_add(&new->list, &mtd_notifiers);
896
Wanlong Gaod5ca5122011-05-20 21:14:30 +0800897 __module_get(THIS_MODULE);
Thomas Gleixner97894cd2005-11-07 11:15:26 +0000898
Ben Hutchingsf1332ba2010-01-29 20:57:11 +0000899 mtd_for_each_device(mtd)
900 new->add(mtd);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700901
Ingo Molnar48b19262006-03-31 02:29:41 -0800902 mutex_unlock(&mtd_table_mutex);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700903}
Artem Bityutskiy33c87b42011-12-30 16:11:14 +0200904EXPORT_SYMBOL_GPL(register_mtd_user);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700905
906/**
Artem B. Bityuckiy49450792005-02-18 14:34:54 +0000907 * unregister_mtd_user - unregister a 'user' of MTD devices.
908 * @old: pointer to notifier info structure
Linus Torvalds1da177e2005-04-16 15:20:36 -0700909 *
910 * Removes a callback function pair from the list of 'users' to be
911 * notified upon addition or removal of MTD devices. Causes the
912 * 'remove' callback to be immediately invoked for each MTD device
913 * currently present in the system.
914 */
Linus Torvalds1da177e2005-04-16 15:20:36 -0700915int unregister_mtd_user (struct mtd_notifier *old)
916{
Ben Hutchingsf1332ba2010-01-29 20:57:11 +0000917 struct mtd_info *mtd;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700918
Ingo Molnar48b19262006-03-31 02:29:41 -0800919 mutex_lock(&mtd_table_mutex);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700920
921 module_put(THIS_MODULE);
922
Ben Hutchingsf1332ba2010-01-29 20:57:11 +0000923 mtd_for_each_device(mtd)
924 old->remove(mtd);
Thomas Gleixner97894cd2005-11-07 11:15:26 +0000925
Linus Torvalds1da177e2005-04-16 15:20:36 -0700926 list_del(&old->list);
Ingo Molnar48b19262006-03-31 02:29:41 -0800927 mutex_unlock(&mtd_table_mutex);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700928 return 0;
929}
Artem Bityutskiy33c87b42011-12-30 16:11:14 +0200930EXPORT_SYMBOL_GPL(unregister_mtd_user);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700931
932/**
933 * get_mtd_device - obtain a validated handle for an MTD device
934 * @mtd: last known address of the required MTD device
935 * @num: internal device number of the required MTD device
936 *
937 * Given a number and NULL address, return the num'th entry in the device
938 * table, if any. Given an address and num == -1, search the device table
939 * for a device with that address and return if it's still present. Given
Artem Bityutskiy9c740342006-10-11 14:52:47 +0300940 * both, return the num'th driver only if its address matches. Return
941 * error code if not.
Linus Torvalds1da177e2005-04-16 15:20:36 -0700942 */
Linus Torvalds1da177e2005-04-16 15:20:36 -0700943struct mtd_info *get_mtd_device(struct mtd_info *mtd, int num)
944{
Ben Hutchingsf1332ba2010-01-29 20:57:11 +0000945 struct mtd_info *ret = NULL, *other;
946 int err = -ENODEV;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700947
Ingo Molnar48b19262006-03-31 02:29:41 -0800948 mutex_lock(&mtd_table_mutex);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700949
950 if (num == -1) {
Ben Hutchingsf1332ba2010-01-29 20:57:11 +0000951 mtd_for_each_device(other) {
952 if (other == mtd) {
953 ret = mtd;
954 break;
955 }
956 }
Ben Hutchingsb520e412010-01-29 20:59:42 +0000957 } else if (num >= 0) {
958 ret = idr_find(&mtd_idr, num);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700959 if (mtd && mtd != ret)
960 ret = NULL;
961 }
962
Maxim Levitsky3bd45652010-02-22 20:39:28 +0200963 if (!ret) {
964 ret = ERR_PTR(err);
965 goto out;
Artem Bityutskiy9fe912c2006-10-11 14:52:45 +0300966 }
Linus Torvalds1da177e2005-04-16 15:20:36 -0700967
Maxim Levitsky3bd45652010-02-22 20:39:28 +0200968 err = __get_mtd_device(ret);
969 if (err)
970 ret = ERR_PTR(err);
971out:
Ingo Molnar48b19262006-03-31 02:29:41 -0800972 mutex_unlock(&mtd_table_mutex);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700973 return ret;
Maxim Levitsky3bd45652010-02-22 20:39:28 +0200974}
Artem Bityutskiy33c87b42011-12-30 16:11:14 +0200975EXPORT_SYMBOL_GPL(get_mtd_device);
Artem Bityutskiy9c740342006-10-11 14:52:47 +0300976
Maxim Levitsky3bd45652010-02-22 20:39:28 +0200977
978int __get_mtd_device(struct mtd_info *mtd)
979{
Miquel Raynal46b58892020-01-14 10:09:52 +0100980 struct mtd_info *master = mtd_get_master(mtd);
Maxim Levitsky3bd45652010-02-22 20:39:28 +0200981 int err;
982
Miquel Raynal46b58892020-01-14 10:09:52 +0100983 if (!try_module_get(master->owner))
Maxim Levitsky3bd45652010-02-22 20:39:28 +0200984 return -ENODEV;
985
Miquel Raynal46b58892020-01-14 10:09:52 +0100986 if (master->_get_device) {
987 err = master->_get_device(mtd);
Maxim Levitsky3bd45652010-02-22 20:39:28 +0200988
989 if (err) {
Miquel Raynal46b58892020-01-14 10:09:52 +0100990 module_put(master->owner);
Maxim Levitsky3bd45652010-02-22 20:39:28 +0200991 return err;
992 }
993 }
Miquel Raynal46b58892020-01-14 10:09:52 +0100994
995 while (mtd->parent) {
996 mtd->usecount++;
997 mtd = mtd->parent;
998 }
999
Maxim Levitsky3bd45652010-02-22 20:39:28 +02001000 return 0;
Linus Torvalds1da177e2005-04-16 15:20:36 -07001001}
Artem Bityutskiy33c87b42011-12-30 16:11:14 +02001002EXPORT_SYMBOL_GPL(__get_mtd_device);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001003
Artem Bityutskiy77993082006-10-11 14:52:44 +03001004/**
1005 * get_mtd_device_nm - obtain a validated handle for an MTD device by
1006 * device name
1007 * @name: MTD device name to open
1008 *
1009 * This function returns MTD device description structure in case of
1010 * success and an error code in case of failure.
1011 */
Artem Bityutskiy77993082006-10-11 14:52:44 +03001012struct mtd_info *get_mtd_device_nm(const char *name)
1013{
Ben Hutchingsf1332ba2010-01-29 20:57:11 +00001014 int err = -ENODEV;
1015 struct mtd_info *mtd = NULL, *other;
Artem Bityutskiy77993082006-10-11 14:52:44 +03001016
1017 mutex_lock(&mtd_table_mutex);
1018
Ben Hutchingsf1332ba2010-01-29 20:57:11 +00001019 mtd_for_each_device(other) {
1020 if (!strcmp(name, other->name)) {
1021 mtd = other;
Artem Bityutskiy77993082006-10-11 14:52:44 +03001022 break;
1023 }
1024 }
1025
Artem Bityutskiy9fe912c2006-10-11 14:52:45 +03001026 if (!mtd)
Artem Bityutskiy77993082006-10-11 14:52:44 +03001027 goto out_unlock;
1028
Wanlong Gao52534f22011-05-17 22:36:18 +08001029 err = __get_mtd_device(mtd);
1030 if (err)
Artem Bityutskiy77993082006-10-11 14:52:44 +03001031 goto out_unlock;
1032
Artem Bityutskiy77993082006-10-11 14:52:44 +03001033 mutex_unlock(&mtd_table_mutex);
1034 return mtd;
Artem Bityutskiy9fe912c2006-10-11 14:52:45 +03001035
Artem Bityutskiy9fe912c2006-10-11 14:52:45 +03001036out_unlock:
1037 mutex_unlock(&mtd_table_mutex);
1038 return ERR_PTR(err);
Artem Bityutskiy77993082006-10-11 14:52:44 +03001039}
Artem Bityutskiy33c87b42011-12-30 16:11:14 +02001040EXPORT_SYMBOL_GPL(get_mtd_device_nm);
Artem Bityutskiy77993082006-10-11 14:52:44 +03001041
Linus Torvalds1da177e2005-04-16 15:20:36 -07001042void put_mtd_device(struct mtd_info *mtd)
1043{
Ingo Molnar48b19262006-03-31 02:29:41 -08001044 mutex_lock(&mtd_table_mutex);
Maxim Levitsky3bd45652010-02-22 20:39:28 +02001045 __put_mtd_device(mtd);
1046 mutex_unlock(&mtd_table_mutex);
1047
1048}
Artem Bityutskiy33c87b42011-12-30 16:11:14 +02001049EXPORT_SYMBOL_GPL(put_mtd_device);
Maxim Levitsky3bd45652010-02-22 20:39:28 +02001050
1051void __put_mtd_device(struct mtd_info *mtd)
1052{
Miquel Raynal46b58892020-01-14 10:09:52 +01001053 struct mtd_info *master = mtd_get_master(mtd);
Maxim Levitsky3bd45652010-02-22 20:39:28 +02001054
Miquel Raynal46b58892020-01-14 10:09:52 +01001055 while (mtd->parent) {
1056 --mtd->usecount;
1057 BUG_ON(mtd->usecount < 0);
1058 mtd = mtd->parent;
1059 }
Linus Torvalds1da177e2005-04-16 15:20:36 -07001060
Miquel Raynal46b58892020-01-14 10:09:52 +01001061 if (master->_put_device)
1062 master->_put_device(master);
1063
1064 module_put(master->owner);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001065}
Artem Bityutskiy33c87b42011-12-30 16:11:14 +02001066EXPORT_SYMBOL_GPL(__put_mtd_device);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001067
Artem Bityutskiy52b02032011-12-30 15:57:25 +02001068/*
Boris Brezillon884cfd92018-02-12 22:03:09 +01001069 * Erase is an synchronous operation. Device drivers are epected to return a
1070 * negative error code if the operation failed and update instr->fail_addr
1071 * to point the portion that was not properly erased.
Artem Bityutskiy8273a0c2012-02-03 14:34:14 +02001072 */
1073int mtd_erase(struct mtd_info *mtd, struct erase_info *instr)
1074{
Miquel Raynal46b58892020-01-14 10:09:52 +01001075 struct mtd_info *master = mtd_get_master(mtd);
1076 u64 mst_ofs = mtd_get_master_ofs(mtd, 0);
1077 int ret;
1078
Boris Brezillonc585da92018-02-12 22:03:07 +01001079 instr->fail_addr = MTD_FAIL_ADDR_UNKNOWN;
1080
Miquel Raynal46b58892020-01-14 10:09:52 +01001081 if (!mtd->erasesize || !master->_erase)
Boris Brezillone6e620f2018-01-22 10:38:01 +01001082 return -ENOTSUPP;
1083
Brian Norris0c2b4e22014-07-21 19:06:27 -07001084 if (instr->addr >= mtd->size || instr->len > mtd->size - instr->addr)
Artem Bityutskiy8273a0c2012-02-03 14:34:14 +02001085 return -EINVAL;
Artem Bityutskiy664addc2012-02-03 18:13:23 +02001086 if (!(mtd->flags & MTD_WRITEABLE))
1087 return -EROFS;
Boris Brezillone6e620f2018-01-22 10:38:01 +01001088
Boris Brezillone7bfb3f2018-02-12 22:03:11 +01001089 if (!instr->len)
Artem Bityutskiybcb1d232012-02-06 13:27:43 +02001090 return 0;
Boris Brezillone7bfb3f2018-02-12 22:03:11 +01001091
Ezequiel Garciafea728c2016-04-12 17:46:42 -03001092 ledtrig_mtd_activity();
Miquel Raynal46b58892020-01-14 10:09:52 +01001093
1094 instr->addr += mst_ofs;
1095 ret = master->_erase(master, instr);
1096 if (instr->fail_addr != MTD_FAIL_ADDR_UNKNOWN)
1097 instr->fail_addr -= mst_ofs;
1098
1099 instr->addr -= mst_ofs;
1100 return ret;
Artem Bityutskiy8273a0c2012-02-03 14:34:14 +02001101}
1102EXPORT_SYMBOL_GPL(mtd_erase);
1103
1104/*
1105 * This stuff for eXecute-In-Place. phys is optional and may be set to NULL.
1106 */
1107int mtd_point(struct mtd_info *mtd, loff_t from, size_t len, size_t *retlen,
1108 void **virt, resource_size_t *phys)
1109{
Miquel Raynal46b58892020-01-14 10:09:52 +01001110 struct mtd_info *master = mtd_get_master(mtd);
1111
Artem Bityutskiy8273a0c2012-02-03 14:34:14 +02001112 *retlen = 0;
Artem Bityutskiy0dd52352012-02-08 15:13:26 +02001113 *virt = NULL;
1114 if (phys)
1115 *phys = 0;
Miquel Raynal46b58892020-01-14 10:09:52 +01001116 if (!master->_point)
Artem Bityutskiy8273a0c2012-02-03 14:34:14 +02001117 return -EOPNOTSUPP;
Brian Norris0c2b4e22014-07-21 19:06:27 -07001118 if (from < 0 || from >= mtd->size || len > mtd->size - from)
Artem Bityutskiy8273a0c2012-02-03 14:34:14 +02001119 return -EINVAL;
Artem Bityutskiybcb1d232012-02-06 13:27:43 +02001120 if (!len)
1121 return 0;
Miquel Raynal46b58892020-01-14 10:09:52 +01001122
1123 from = mtd_get_master_ofs(mtd, from);
1124 return master->_point(master, from, len, retlen, virt, phys);
Artem Bityutskiy8273a0c2012-02-03 14:34:14 +02001125}
1126EXPORT_SYMBOL_GPL(mtd_point);
1127
1128/* We probably shouldn't allow XIP if the unpoint isn't a NULL */
1129int mtd_unpoint(struct mtd_info *mtd, loff_t from, size_t len)
1130{
Miquel Raynal46b58892020-01-14 10:09:52 +01001131 struct mtd_info *master = mtd_get_master(mtd);
1132
1133 if (!master->_unpoint)
Artem Bityutskiy8273a0c2012-02-03 14:34:14 +02001134 return -EOPNOTSUPP;
Brian Norris0c2b4e22014-07-21 19:06:27 -07001135 if (from < 0 || from >= mtd->size || len > mtd->size - from)
Artem Bityutskiy8273a0c2012-02-03 14:34:14 +02001136 return -EINVAL;
Artem Bityutskiybcb1d232012-02-06 13:27:43 +02001137 if (!len)
1138 return 0;
Miquel Raynal46b58892020-01-14 10:09:52 +01001139 return master->_unpoint(master, mtd_get_master_ofs(mtd, from), len);
Artem Bityutskiy8273a0c2012-02-03 14:34:14 +02001140}
1141EXPORT_SYMBOL_GPL(mtd_unpoint);
1142
1143/*
1144 * Allow NOMMU mmap() to directly map the device (if not NULL)
1145 * - return the address to which the offset maps
1146 * - return -ENOSYS to indicate refusal to do the mapping
1147 */
1148unsigned long mtd_get_unmapped_area(struct mtd_info *mtd, unsigned long len,
1149 unsigned long offset, unsigned long flags)
1150{
Nicolas Pitre9eaa9032017-10-30 14:48:32 -04001151 size_t retlen;
1152 void *virt;
1153 int ret;
1154
1155 ret = mtd_point(mtd, offset, len, &retlen, &virt, NULL);
1156 if (ret)
1157 return ret;
1158 if (retlen != len) {
1159 mtd_unpoint(mtd, offset, retlen);
1160 return -ENOSYS;
1161 }
1162 return (unsigned long)virt;
Artem Bityutskiy8273a0c2012-02-03 14:34:14 +02001163}
1164EXPORT_SYMBOL_GPL(mtd_get_unmapped_area);
1165
Miquel Raynal46b58892020-01-14 10:09:52 +01001166static void mtd_update_ecc_stats(struct mtd_info *mtd, struct mtd_info *master,
1167 const struct mtd_ecc_stats *old_stats)
1168{
1169 struct mtd_ecc_stats diff;
1170
1171 if (master == mtd)
1172 return;
1173
1174 diff = master->ecc_stats;
1175 diff.failed -= old_stats->failed;
1176 diff.corrected -= old_stats->corrected;
1177
1178 while (mtd->parent) {
1179 mtd->ecc_stats.failed += diff.failed;
1180 mtd->ecc_stats.corrected += diff.corrected;
1181 mtd = mtd->parent;
1182 }
1183}
1184
Artem Bityutskiy8273a0c2012-02-03 14:34:14 +02001185int mtd_read(struct mtd_info *mtd, loff_t from, size_t len, size_t *retlen,
1186 u_char *buf)
1187{
Boris Brezillon2431c4f2018-12-20 15:13:20 +01001188 struct mtd_oob_ops ops = {
1189 .len = len,
1190 .datbuf = buf,
1191 };
1192 int ret;
Mike Dunnedbc45402012-04-25 12:06:11 -07001193
Boris Brezillon2431c4f2018-12-20 15:13:20 +01001194 ret = mtd_read_oob(mtd, from, &ops);
1195 *retlen = ops.retlen;
Boris Brezillon24ff1292018-01-09 09:50:34 +01001196
Boris Brezillon2431c4f2018-12-20 15:13:20 +01001197 return ret;
Artem Bityutskiy8273a0c2012-02-03 14:34:14 +02001198}
1199EXPORT_SYMBOL_GPL(mtd_read);
1200
1201int mtd_write(struct mtd_info *mtd, loff_t to, size_t len, size_t *retlen,
1202 const u_char *buf)
1203{
Boris Brezillon2431c4f2018-12-20 15:13:20 +01001204 struct mtd_oob_ops ops = {
1205 .len = len,
1206 .datbuf = (u8 *)buf,
1207 };
1208 int ret;
Boris Brezillon24ff1292018-01-09 09:50:34 +01001209
Boris Brezillon2431c4f2018-12-20 15:13:20 +01001210 ret = mtd_write_oob(mtd, to, &ops);
1211 *retlen = ops.retlen;
Boris Brezillon24ff1292018-01-09 09:50:34 +01001212
Boris Brezillon2431c4f2018-12-20 15:13:20 +01001213 return ret;
Artem Bityutskiy8273a0c2012-02-03 14:34:14 +02001214}
1215EXPORT_SYMBOL_GPL(mtd_write);
1216
1217/*
1218 * In blackbox flight recorder like scenarios we want to make successful writes
1219 * in interrupt context. panic_write() is only intended to be called when its
1220 * known the kernel is about to panic and we need the write to succeed. Since
1221 * the kernel is not going to be running for much longer, this function can
1222 * break locks and delay to ensure the write succeeds (but not sleep).
1223 */
1224int mtd_panic_write(struct mtd_info *mtd, loff_t to, size_t len, size_t *retlen,
1225 const u_char *buf)
1226{
Miquel Raynal46b58892020-01-14 10:09:52 +01001227 struct mtd_info *master = mtd_get_master(mtd);
1228
Artem Bityutskiy8273a0c2012-02-03 14:34:14 +02001229 *retlen = 0;
Miquel Raynal46b58892020-01-14 10:09:52 +01001230 if (!master->_panic_write)
Artem Bityutskiy8273a0c2012-02-03 14:34:14 +02001231 return -EOPNOTSUPP;
Brian Norris0c2b4e22014-07-21 19:06:27 -07001232 if (to < 0 || to >= mtd->size || len > mtd->size - to)
Artem Bityutskiy8273a0c2012-02-03 14:34:14 +02001233 return -EINVAL;
Artem Bityutskiy664addc2012-02-03 18:13:23 +02001234 if (!(mtd->flags & MTD_WRITEABLE))
1235 return -EROFS;
Artem Bityutskiybcb1d232012-02-06 13:27:43 +02001236 if (!len)
1237 return 0;
Kamal Dasu9f897bf2019-05-16 12:41:46 -04001238 if (!mtd->oops_panic_write)
1239 mtd->oops_panic_write = true;
1240
Miquel Raynal46b58892020-01-14 10:09:52 +01001241 return master->_panic_write(master, mtd_get_master_ofs(mtd, to), len,
1242 retlen, buf);
Artem Bityutskiy8273a0c2012-02-03 14:34:14 +02001243}
1244EXPORT_SYMBOL_GPL(mtd_panic_write);
1245
Boris Brezillon5cdd9292017-06-27 21:22:21 +02001246static int mtd_check_oob_ops(struct mtd_info *mtd, loff_t offs,
1247 struct mtd_oob_ops *ops)
1248{
1249 /*
1250 * Some users are setting ->datbuf or ->oobbuf to NULL, but are leaving
1251 * ->len or ->ooblen uninitialized. Force ->len and ->ooblen to 0 in
1252 * this case.
1253 */
1254 if (!ops->datbuf)
1255 ops->len = 0;
1256
1257 if (!ops->oobbuf)
1258 ops->ooblen = 0;
1259
Miquel Raynald82c3682017-12-18 08:26:28 +01001260 if (offs < 0 || offs + ops->len > mtd->size)
Boris Brezillon5cdd9292017-06-27 21:22:21 +02001261 return -EINVAL;
1262
1263 if (ops->ooblen) {
Miquel Raynal89f706d2018-11-18 21:18:31 +01001264 size_t maxooblen;
Boris Brezillon5cdd9292017-06-27 21:22:21 +02001265
1266 if (ops->ooboffs >= mtd_oobavail(mtd, ops))
1267 return -EINVAL;
1268
Miquel Raynal89f706d2018-11-18 21:18:31 +01001269 maxooblen = ((size_t)(mtd_div_by_ws(mtd->size, mtd) -
1270 mtd_div_by_ws(offs, mtd)) *
Boris Brezillon5cdd9292017-06-27 21:22:21 +02001271 mtd_oobavail(mtd, ops)) - ops->ooboffs;
1272 if (ops->ooblen > maxooblen)
1273 return -EINVAL;
1274 }
1275
1276 return 0;
1277}
1278
Brian Norrisd2d48482012-06-22 16:35:38 -07001279int mtd_read_oob(struct mtd_info *mtd, loff_t from, struct mtd_oob_ops *ops)
1280{
Miquel Raynal46b58892020-01-14 10:09:52 +01001281 struct mtd_info *master = mtd_get_master(mtd);
1282 struct mtd_ecc_stats old_stats = master->ecc_stats;
Brian Norrise47f6852012-06-22 16:35:39 -07001283 int ret_code;
Miquel Raynal46b58892020-01-14 10:09:52 +01001284
Brian Norrisd2d48482012-06-22 16:35:38 -07001285 ops->retlen = ops->oobretlen = 0;
Ezequiel Garciafea728c2016-04-12 17:46:42 -03001286
Boris Brezillon5cdd9292017-06-27 21:22:21 +02001287 ret_code = mtd_check_oob_ops(mtd, from, ops);
1288 if (ret_code)
1289 return ret_code;
1290
Ezequiel Garciafea728c2016-04-12 17:46:42 -03001291 ledtrig_mtd_activity();
Miquel Raynal89fd23e2018-07-14 14:42:00 +02001292
1293 /* Check the validity of a potential fallback on mtd->_read */
Miquel Raynal46b58892020-01-14 10:09:52 +01001294 if (!master->_read_oob && (!master->_read || ops->oobbuf))
Miquel Raynal89fd23e2018-07-14 14:42:00 +02001295 return -EOPNOTSUPP;
1296
Miquel Raynal46b58892020-01-14 10:09:52 +01001297 from = mtd_get_master_ofs(mtd, from);
1298 if (master->_read_oob)
1299 ret_code = master->_read_oob(master, from, ops);
Miquel Raynal89fd23e2018-07-14 14:42:00 +02001300 else
Miquel Raynal46b58892020-01-14 10:09:52 +01001301 ret_code = master->_read(master, from, ops->len, &ops->retlen,
1302 ops->datbuf);
1303
1304 mtd_update_ecc_stats(mtd, master, &old_stats);
Miquel Raynal89fd23e2018-07-14 14:42:00 +02001305
Brian Norrise47f6852012-06-22 16:35:39 -07001306 /*
1307 * In cases where ops->datbuf != NULL, mtd->_read_oob() has semantics
1308 * similar to mtd->_read(), returning a non-negative integer
1309 * representing max bitflips. In other cases, mtd->_read_oob() may
1310 * return -EUCLEAN. In all cases, perform similar logic to mtd_read().
1311 */
Brian Norrise47f6852012-06-22 16:35:39 -07001312 if (unlikely(ret_code < 0))
1313 return ret_code;
1314 if (mtd->ecc_strength == 0)
1315 return 0; /* device lacks ecc */
1316 return ret_code >= mtd->bitflip_threshold ? -EUCLEAN : 0;
Brian Norrisd2d48482012-06-22 16:35:38 -07001317}
1318EXPORT_SYMBOL_GPL(mtd_read_oob);
1319
Ezequiel Garcia0c034fe2016-04-12 17:46:39 -03001320int mtd_write_oob(struct mtd_info *mtd, loff_t to,
1321 struct mtd_oob_ops *ops)
1322{
Miquel Raynal46b58892020-01-14 10:09:52 +01001323 struct mtd_info *master = mtd_get_master(mtd);
Boris Brezillon5cdd9292017-06-27 21:22:21 +02001324 int ret;
1325
Ezequiel Garcia0c034fe2016-04-12 17:46:39 -03001326 ops->retlen = ops->oobretlen = 0;
Miquel Raynal89fd23e2018-07-14 14:42:00 +02001327
Ezequiel Garcia0c034fe2016-04-12 17:46:39 -03001328 if (!(mtd->flags & MTD_WRITEABLE))
1329 return -EROFS;
Boris Brezillon5cdd9292017-06-27 21:22:21 +02001330
1331 ret = mtd_check_oob_ops(mtd, to, ops);
1332 if (ret)
1333 return ret;
1334
Ezequiel Garciafea728c2016-04-12 17:46:42 -03001335 ledtrig_mtd_activity();
Miquel Raynal89fd23e2018-07-14 14:42:00 +02001336
1337 /* Check the validity of a potential fallback on mtd->_write */
Miquel Raynal46b58892020-01-14 10:09:52 +01001338 if (!master->_write_oob && (!master->_write || ops->oobbuf))
Miquel Raynal89fd23e2018-07-14 14:42:00 +02001339 return -EOPNOTSUPP;
1340
Miquel Raynal46b58892020-01-14 10:09:52 +01001341 to = mtd_get_master_ofs(mtd, to);
1342
1343 if (master->_write_oob)
1344 return master->_write_oob(master, to, ops);
Miquel Raynal89fd23e2018-07-14 14:42:00 +02001345 else
Miquel Raynal46b58892020-01-14 10:09:52 +01001346 return master->_write(master, to, ops->len, &ops->retlen,
1347 ops->datbuf);
Ezequiel Garcia0c034fe2016-04-12 17:46:39 -03001348}
1349EXPORT_SYMBOL_GPL(mtd_write_oob);
1350
Boris Brezillon75eb2ce2016-02-04 09:52:30 +01001351/**
1352 * mtd_ooblayout_ecc - Get the OOB region definition of a specific ECC section
1353 * @mtd: MTD device structure
1354 * @section: ECC section. Depending on the layout you may have all the ECC
1355 * bytes stored in a single contiguous section, or one section
1356 * per ECC chunk (and sometime several sections for a single ECC
1357 * ECC chunk)
1358 * @oobecc: OOB region struct filled with the appropriate ECC position
1359 * information
1360 *
Masahiro Yamada7da0fff2016-12-14 09:31:01 +09001361 * This function returns ECC section information in the OOB area. If you want
Boris Brezillon75eb2ce2016-02-04 09:52:30 +01001362 * to get all the ECC bytes information, then you should call
1363 * mtd_ooblayout_ecc(mtd, section++, oobecc) until it returns -ERANGE.
1364 *
1365 * Returns zero on success, a negative error code otherwise.
1366 */
1367int mtd_ooblayout_ecc(struct mtd_info *mtd, int section,
1368 struct mtd_oob_region *oobecc)
1369{
Miquel Raynal46b58892020-01-14 10:09:52 +01001370 struct mtd_info *master = mtd_get_master(mtd);
1371
Boris Brezillon75eb2ce2016-02-04 09:52:30 +01001372 memset(oobecc, 0, sizeof(*oobecc));
1373
Miquel Raynal46b58892020-01-14 10:09:52 +01001374 if (!master || section < 0)
Boris Brezillon75eb2ce2016-02-04 09:52:30 +01001375 return -EINVAL;
1376
Miquel Raynal46b58892020-01-14 10:09:52 +01001377 if (!master->ooblayout || !master->ooblayout->ecc)
Boris Brezillon75eb2ce2016-02-04 09:52:30 +01001378 return -ENOTSUPP;
1379
Miquel Raynal46b58892020-01-14 10:09:52 +01001380 return master->ooblayout->ecc(master, section, oobecc);
Boris Brezillon75eb2ce2016-02-04 09:52:30 +01001381}
1382EXPORT_SYMBOL_GPL(mtd_ooblayout_ecc);
1383
1384/**
1385 * mtd_ooblayout_free - Get the OOB region definition of a specific free
1386 * section
1387 * @mtd: MTD device structure
1388 * @section: Free section you are interested in. Depending on the layout
1389 * you may have all the free bytes stored in a single contiguous
1390 * section, or one section per ECC chunk plus an extra section
1391 * for the remaining bytes (or other funky layout).
1392 * @oobfree: OOB region struct filled with the appropriate free position
1393 * information
1394 *
Masahiro Yamada7da0fff2016-12-14 09:31:01 +09001395 * This function returns free bytes position in the OOB area. If you want
Boris Brezillon75eb2ce2016-02-04 09:52:30 +01001396 * to get all the free bytes information, then you should call
1397 * mtd_ooblayout_free(mtd, section++, oobfree) until it returns -ERANGE.
1398 *
1399 * Returns zero on success, a negative error code otherwise.
1400 */
1401int mtd_ooblayout_free(struct mtd_info *mtd, int section,
1402 struct mtd_oob_region *oobfree)
1403{
Miquel Raynal46b58892020-01-14 10:09:52 +01001404 struct mtd_info *master = mtd_get_master(mtd);
1405
Boris Brezillon75eb2ce2016-02-04 09:52:30 +01001406 memset(oobfree, 0, sizeof(*oobfree));
1407
Miquel Raynal46b58892020-01-14 10:09:52 +01001408 if (!master || section < 0)
Boris Brezillon75eb2ce2016-02-04 09:52:30 +01001409 return -EINVAL;
1410
Miquel Raynal46b58892020-01-14 10:09:52 +01001411 if (!master->ooblayout || !master->ooblayout->free)
Boris Brezillon75eb2ce2016-02-04 09:52:30 +01001412 return -ENOTSUPP;
1413
Miquel Raynal46b58892020-01-14 10:09:52 +01001414 return master->ooblayout->free(master, section, oobfree);
Boris Brezillon75eb2ce2016-02-04 09:52:30 +01001415}
1416EXPORT_SYMBOL_GPL(mtd_ooblayout_free);
1417
1418/**
1419 * mtd_ooblayout_find_region - Find the region attached to a specific byte
1420 * @mtd: mtd info structure
1421 * @byte: the byte we are searching for
1422 * @sectionp: pointer where the section id will be stored
1423 * @oobregion: used to retrieve the ECC position
1424 * @iter: iterator function. Should be either mtd_ooblayout_free or
1425 * mtd_ooblayout_ecc depending on the region type you're searching for
1426 *
Masahiro Yamada7da0fff2016-12-14 09:31:01 +09001427 * This function returns the section id and oobregion information of a
Boris Brezillon75eb2ce2016-02-04 09:52:30 +01001428 * specific byte. For example, say you want to know where the 4th ECC byte is
1429 * stored, you'll use:
1430 *
1431 * mtd_ooblayout_find_region(mtd, 3, &section, &oobregion, mtd_ooblayout_ecc);
1432 *
1433 * Returns zero on success, a negative error code otherwise.
1434 */
1435static int mtd_ooblayout_find_region(struct mtd_info *mtd, int byte,
1436 int *sectionp, struct mtd_oob_region *oobregion,
1437 int (*iter)(struct mtd_info *,
1438 int section,
1439 struct mtd_oob_region *oobregion))
1440{
1441 int pos = 0, ret, section = 0;
1442
1443 memset(oobregion, 0, sizeof(*oobregion));
1444
1445 while (1) {
1446 ret = iter(mtd, section, oobregion);
1447 if (ret)
1448 return ret;
1449
1450 if (pos + oobregion->length > byte)
1451 break;
1452
1453 pos += oobregion->length;
1454 section++;
1455 }
1456
1457 /*
1458 * Adjust region info to make it start at the beginning at the
1459 * 'start' ECC byte.
1460 */
1461 oobregion->offset += byte - pos;
1462 oobregion->length -= byte - pos;
1463 *sectionp = section;
1464
1465 return 0;
1466}
1467
1468/**
1469 * mtd_ooblayout_find_eccregion - Find the ECC region attached to a specific
1470 * ECC byte
1471 * @mtd: mtd info structure
1472 * @eccbyte: the byte we are searching for
1473 * @sectionp: pointer where the section id will be stored
1474 * @oobregion: OOB region information
1475 *
1476 * Works like mtd_ooblayout_find_region() except it searches for a specific ECC
1477 * byte.
1478 *
1479 * Returns zero on success, a negative error code otherwise.
1480 */
1481int mtd_ooblayout_find_eccregion(struct mtd_info *mtd, int eccbyte,
1482 int *section,
1483 struct mtd_oob_region *oobregion)
1484{
1485 return mtd_ooblayout_find_region(mtd, eccbyte, section, oobregion,
1486 mtd_ooblayout_ecc);
1487}
1488EXPORT_SYMBOL_GPL(mtd_ooblayout_find_eccregion);
1489
1490/**
1491 * mtd_ooblayout_get_bytes - Extract OOB bytes from the oob buffer
1492 * @mtd: mtd info structure
1493 * @buf: destination buffer to store OOB bytes
1494 * @oobbuf: OOB buffer
1495 * @start: first byte to retrieve
1496 * @nbytes: number of bytes to retrieve
1497 * @iter: section iterator
1498 *
1499 * Extract bytes attached to a specific category (ECC or free)
1500 * from the OOB buffer and copy them into buf.
1501 *
1502 * Returns zero on success, a negative error code otherwise.
1503 */
1504static int mtd_ooblayout_get_bytes(struct mtd_info *mtd, u8 *buf,
1505 const u8 *oobbuf, int start, int nbytes,
1506 int (*iter)(struct mtd_info *,
1507 int section,
1508 struct mtd_oob_region *oobregion))
1509{
Masahiro Yamada8e8fd4d2016-11-09 11:08:08 +09001510 struct mtd_oob_region oobregion;
1511 int section, ret;
Boris Brezillon75eb2ce2016-02-04 09:52:30 +01001512
1513 ret = mtd_ooblayout_find_region(mtd, start, &section,
1514 &oobregion, iter);
1515
1516 while (!ret) {
1517 int cnt;
1518
Masahiro Yamada7c295ef2016-11-09 11:08:09 +09001519 cnt = min_t(int, nbytes, oobregion.length);
Boris Brezillon75eb2ce2016-02-04 09:52:30 +01001520 memcpy(buf, oobbuf + oobregion.offset, cnt);
1521 buf += cnt;
1522 nbytes -= cnt;
1523
1524 if (!nbytes)
1525 break;
1526
1527 ret = iter(mtd, ++section, &oobregion);
1528 }
1529
1530 return ret;
1531}
1532
1533/**
1534 * mtd_ooblayout_set_bytes - put OOB bytes into the oob buffer
1535 * @mtd: mtd info structure
1536 * @buf: source buffer to get OOB bytes from
1537 * @oobbuf: OOB buffer
1538 * @start: first OOB byte to set
1539 * @nbytes: number of OOB bytes to set
1540 * @iter: section iterator
1541 *
1542 * Fill the OOB buffer with data provided in buf. The category (ECC or free)
1543 * is selected by passing the appropriate iterator.
1544 *
1545 * Returns zero on success, a negative error code otherwise.
1546 */
1547static int mtd_ooblayout_set_bytes(struct mtd_info *mtd, const u8 *buf,
1548 u8 *oobbuf, int start, int nbytes,
1549 int (*iter)(struct mtd_info *,
1550 int section,
1551 struct mtd_oob_region *oobregion))
1552{
Masahiro Yamada8e8fd4d2016-11-09 11:08:08 +09001553 struct mtd_oob_region oobregion;
1554 int section, ret;
Boris Brezillon75eb2ce2016-02-04 09:52:30 +01001555
1556 ret = mtd_ooblayout_find_region(mtd, start, &section,
1557 &oobregion, iter);
1558
1559 while (!ret) {
1560 int cnt;
1561
Masahiro Yamada7c295ef2016-11-09 11:08:09 +09001562 cnt = min_t(int, nbytes, oobregion.length);
Boris Brezillon75eb2ce2016-02-04 09:52:30 +01001563 memcpy(oobbuf + oobregion.offset, buf, cnt);
1564 buf += cnt;
1565 nbytes -= cnt;
1566
1567 if (!nbytes)
1568 break;
1569
1570 ret = iter(mtd, ++section, &oobregion);
1571 }
1572
1573 return ret;
1574}
1575
1576/**
1577 * mtd_ooblayout_count_bytes - count the number of bytes in a OOB category
1578 * @mtd: mtd info structure
1579 * @iter: category iterator
1580 *
1581 * Count the number of bytes in a given category.
1582 *
1583 * Returns a positive value on success, a negative error code otherwise.
1584 */
1585static int mtd_ooblayout_count_bytes(struct mtd_info *mtd,
1586 int (*iter)(struct mtd_info *,
1587 int section,
1588 struct mtd_oob_region *oobregion))
1589{
Masahiro Yamada4d6aecf2016-11-09 11:08:10 +09001590 struct mtd_oob_region oobregion;
Boris Brezillon75eb2ce2016-02-04 09:52:30 +01001591 int section = 0, ret, nbytes = 0;
1592
1593 while (1) {
1594 ret = iter(mtd, section++, &oobregion);
1595 if (ret) {
1596 if (ret == -ERANGE)
1597 ret = nbytes;
1598 break;
1599 }
1600
1601 nbytes += oobregion.length;
1602 }
1603
1604 return ret;
1605}
1606
1607/**
1608 * mtd_ooblayout_get_eccbytes - extract ECC bytes from the oob buffer
1609 * @mtd: mtd info structure
1610 * @eccbuf: destination buffer to store ECC bytes
1611 * @oobbuf: OOB buffer
1612 * @start: first ECC byte to retrieve
1613 * @nbytes: number of ECC bytes to retrieve
1614 *
1615 * Works like mtd_ooblayout_get_bytes(), except it acts on ECC bytes.
1616 *
1617 * Returns zero on success, a negative error code otherwise.
1618 */
1619int mtd_ooblayout_get_eccbytes(struct mtd_info *mtd, u8 *eccbuf,
1620 const u8 *oobbuf, int start, int nbytes)
1621{
1622 return mtd_ooblayout_get_bytes(mtd, eccbuf, oobbuf, start, nbytes,
1623 mtd_ooblayout_ecc);
1624}
1625EXPORT_SYMBOL_GPL(mtd_ooblayout_get_eccbytes);
1626
1627/**
1628 * mtd_ooblayout_set_eccbytes - set ECC bytes into the oob buffer
1629 * @mtd: mtd info structure
1630 * @eccbuf: source buffer to get ECC bytes from
1631 * @oobbuf: OOB buffer
1632 * @start: first ECC byte to set
1633 * @nbytes: number of ECC bytes to set
1634 *
1635 * Works like mtd_ooblayout_set_bytes(), except it acts on ECC bytes.
1636 *
1637 * Returns zero on success, a negative error code otherwise.
1638 */
1639int mtd_ooblayout_set_eccbytes(struct mtd_info *mtd, const u8 *eccbuf,
1640 u8 *oobbuf, int start, int nbytes)
1641{
1642 return mtd_ooblayout_set_bytes(mtd, eccbuf, oobbuf, start, nbytes,
1643 mtd_ooblayout_ecc);
1644}
1645EXPORT_SYMBOL_GPL(mtd_ooblayout_set_eccbytes);
1646
1647/**
1648 * mtd_ooblayout_get_databytes - extract data bytes from the oob buffer
1649 * @mtd: mtd info structure
1650 * @databuf: destination buffer to store ECC bytes
1651 * @oobbuf: OOB buffer
1652 * @start: first ECC byte to retrieve
1653 * @nbytes: number of ECC bytes to retrieve
1654 *
1655 * Works like mtd_ooblayout_get_bytes(), except it acts on free bytes.
1656 *
1657 * Returns zero on success, a negative error code otherwise.
1658 */
1659int mtd_ooblayout_get_databytes(struct mtd_info *mtd, u8 *databuf,
1660 const u8 *oobbuf, int start, int nbytes)
1661{
1662 return mtd_ooblayout_get_bytes(mtd, databuf, oobbuf, start, nbytes,
1663 mtd_ooblayout_free);
1664}
1665EXPORT_SYMBOL_GPL(mtd_ooblayout_get_databytes);
1666
1667/**
Xiaolei Lic77a9312018-03-29 09:34:58 +08001668 * mtd_ooblayout_set_databytes - set data bytes into the oob buffer
Boris Brezillon75eb2ce2016-02-04 09:52:30 +01001669 * @mtd: mtd info structure
Xiaolei Lic77a9312018-03-29 09:34:58 +08001670 * @databuf: source buffer to get data bytes from
Boris Brezillon75eb2ce2016-02-04 09:52:30 +01001671 * @oobbuf: OOB buffer
1672 * @start: first ECC byte to set
1673 * @nbytes: number of ECC bytes to set
1674 *
1675 * Works like mtd_ooblayout_get_bytes(), except it acts on free bytes.
1676 *
1677 * Returns zero on success, a negative error code otherwise.
1678 */
1679int mtd_ooblayout_set_databytes(struct mtd_info *mtd, const u8 *databuf,
1680 u8 *oobbuf, int start, int nbytes)
1681{
1682 return mtd_ooblayout_set_bytes(mtd, databuf, oobbuf, start, nbytes,
1683 mtd_ooblayout_free);
1684}
1685EXPORT_SYMBOL_GPL(mtd_ooblayout_set_databytes);
1686
1687/**
1688 * mtd_ooblayout_count_freebytes - count the number of free bytes in OOB
1689 * @mtd: mtd info structure
1690 *
1691 * Works like mtd_ooblayout_count_bytes(), except it count free bytes.
1692 *
1693 * Returns zero on success, a negative error code otherwise.
1694 */
1695int mtd_ooblayout_count_freebytes(struct mtd_info *mtd)
1696{
1697 return mtd_ooblayout_count_bytes(mtd, mtd_ooblayout_free);
1698}
1699EXPORT_SYMBOL_GPL(mtd_ooblayout_count_freebytes);
1700
1701/**
Xiaolei Lic77a9312018-03-29 09:34:58 +08001702 * mtd_ooblayout_count_eccbytes - count the number of ECC bytes in OOB
Boris Brezillon75eb2ce2016-02-04 09:52:30 +01001703 * @mtd: mtd info structure
1704 *
1705 * Works like mtd_ooblayout_count_bytes(), except it count ECC bytes.
1706 *
1707 * Returns zero on success, a negative error code otherwise.
1708 */
1709int mtd_ooblayout_count_eccbytes(struct mtd_info *mtd)
1710{
1711 return mtd_ooblayout_count_bytes(mtd, mtd_ooblayout_ecc);
1712}
1713EXPORT_SYMBOL_GPL(mtd_ooblayout_count_eccbytes);
1714
Artem Bityutskiyde3cac92012-02-08 16:37:14 +02001715/*
1716 * Method to access the protection register area, present in some flash
1717 * devices. The user data is one time programmable but the factory data is read
1718 * only.
1719 */
Christian Riesch4b78fc42014-01-28 09:29:44 +01001720int mtd_get_fact_prot_info(struct mtd_info *mtd, size_t len, size_t *retlen,
1721 struct otp_info *buf)
Artem Bityutskiyde3cac92012-02-08 16:37:14 +02001722{
Miquel Raynal46b58892020-01-14 10:09:52 +01001723 struct mtd_info *master = mtd_get_master(mtd);
1724
1725 if (!master->_get_fact_prot_info)
Artem Bityutskiyde3cac92012-02-08 16:37:14 +02001726 return -EOPNOTSUPP;
1727 if (!len)
1728 return 0;
Miquel Raynal46b58892020-01-14 10:09:52 +01001729 return master->_get_fact_prot_info(master, len, retlen, buf);
Artem Bityutskiyde3cac92012-02-08 16:37:14 +02001730}
1731EXPORT_SYMBOL_GPL(mtd_get_fact_prot_info);
1732
1733int mtd_read_fact_prot_reg(struct mtd_info *mtd, loff_t from, size_t len,
1734 size_t *retlen, u_char *buf)
1735{
Miquel Raynal46b58892020-01-14 10:09:52 +01001736 struct mtd_info *master = mtd_get_master(mtd);
1737
Artem Bityutskiyde3cac92012-02-08 16:37:14 +02001738 *retlen = 0;
Miquel Raynal46b58892020-01-14 10:09:52 +01001739 if (!master->_read_fact_prot_reg)
Artem Bityutskiyde3cac92012-02-08 16:37:14 +02001740 return -EOPNOTSUPP;
1741 if (!len)
1742 return 0;
Miquel Raynal46b58892020-01-14 10:09:52 +01001743 return master->_read_fact_prot_reg(master, from, len, retlen, buf);
Artem Bityutskiyde3cac92012-02-08 16:37:14 +02001744}
1745EXPORT_SYMBOL_GPL(mtd_read_fact_prot_reg);
1746
Christian Riesch4b78fc42014-01-28 09:29:44 +01001747int mtd_get_user_prot_info(struct mtd_info *mtd, size_t len, size_t *retlen,
1748 struct otp_info *buf)
Artem Bityutskiyde3cac92012-02-08 16:37:14 +02001749{
Miquel Raynal46b58892020-01-14 10:09:52 +01001750 struct mtd_info *master = mtd_get_master(mtd);
1751
1752 if (!master->_get_user_prot_info)
Artem Bityutskiyde3cac92012-02-08 16:37:14 +02001753 return -EOPNOTSUPP;
1754 if (!len)
1755 return 0;
Miquel Raynal46b58892020-01-14 10:09:52 +01001756 return master->_get_user_prot_info(master, len, retlen, buf);
Artem Bityutskiyde3cac92012-02-08 16:37:14 +02001757}
1758EXPORT_SYMBOL_GPL(mtd_get_user_prot_info);
1759
1760int mtd_read_user_prot_reg(struct mtd_info *mtd, loff_t from, size_t len,
1761 size_t *retlen, u_char *buf)
1762{
Miquel Raynal46b58892020-01-14 10:09:52 +01001763 struct mtd_info *master = mtd_get_master(mtd);
1764
Artem Bityutskiyde3cac92012-02-08 16:37:14 +02001765 *retlen = 0;
Miquel Raynal46b58892020-01-14 10:09:52 +01001766 if (!master->_read_user_prot_reg)
Artem Bityutskiyde3cac92012-02-08 16:37:14 +02001767 return -EOPNOTSUPP;
1768 if (!len)
1769 return 0;
Miquel Raynal46b58892020-01-14 10:09:52 +01001770 return master->_read_user_prot_reg(master, from, len, retlen, buf);
Artem Bityutskiyde3cac92012-02-08 16:37:14 +02001771}
1772EXPORT_SYMBOL_GPL(mtd_read_user_prot_reg);
1773
1774int mtd_write_user_prot_reg(struct mtd_info *mtd, loff_t to, size_t len,
1775 size_t *retlen, u_char *buf)
1776{
Miquel Raynal46b58892020-01-14 10:09:52 +01001777 struct mtd_info *master = mtd_get_master(mtd);
Christian Riesch9a78bc82014-03-06 12:42:37 +01001778 int ret;
1779
Artem Bityutskiyde3cac92012-02-08 16:37:14 +02001780 *retlen = 0;
Miquel Raynal46b58892020-01-14 10:09:52 +01001781 if (!master->_write_user_prot_reg)
Artem Bityutskiyde3cac92012-02-08 16:37:14 +02001782 return -EOPNOTSUPP;
1783 if (!len)
1784 return 0;
Miquel Raynal46b58892020-01-14 10:09:52 +01001785 ret = master->_write_user_prot_reg(master, to, len, retlen, buf);
Christian Riesch9a78bc82014-03-06 12:42:37 +01001786 if (ret)
1787 return ret;
1788
1789 /*
1790 * If no data could be written at all, we are out of memory and
1791 * must return -ENOSPC.
1792 */
1793 return (*retlen) ? 0 : -ENOSPC;
Artem Bityutskiyde3cac92012-02-08 16:37:14 +02001794}
1795EXPORT_SYMBOL_GPL(mtd_write_user_prot_reg);
1796
1797int mtd_lock_user_prot_reg(struct mtd_info *mtd, loff_t from, size_t len)
1798{
Miquel Raynal46b58892020-01-14 10:09:52 +01001799 struct mtd_info *master = mtd_get_master(mtd);
1800
1801 if (!master->_lock_user_prot_reg)
Artem Bityutskiyde3cac92012-02-08 16:37:14 +02001802 return -EOPNOTSUPP;
1803 if (!len)
1804 return 0;
Miquel Raynal46b58892020-01-14 10:09:52 +01001805 return master->_lock_user_prot_reg(master, from, len);
Artem Bityutskiyde3cac92012-02-08 16:37:14 +02001806}
1807EXPORT_SYMBOL_GPL(mtd_lock_user_prot_reg);
1808
Artem Bityutskiy8273a0c2012-02-03 14:34:14 +02001809/* Chip-supported device locking */
1810int mtd_lock(struct mtd_info *mtd, loff_t ofs, uint64_t len)
1811{
Miquel Raynal46b58892020-01-14 10:09:52 +01001812 struct mtd_info *master = mtd_get_master(mtd);
1813
1814 if (!master->_lock)
Artem Bityutskiy8273a0c2012-02-03 14:34:14 +02001815 return -EOPNOTSUPP;
Brian Norris0c2b4e22014-07-21 19:06:27 -07001816 if (ofs < 0 || ofs >= mtd->size || len > mtd->size - ofs)
Artem Bityutskiy8273a0c2012-02-03 14:34:14 +02001817 return -EINVAL;
Artem Bityutskiybcb1d232012-02-06 13:27:43 +02001818 if (!len)
1819 return 0;
Miquel Raynal46b58892020-01-14 10:09:52 +01001820 return master->_lock(master, mtd_get_master_ofs(mtd, ofs), len);
Artem Bityutskiy8273a0c2012-02-03 14:34:14 +02001821}
1822EXPORT_SYMBOL_GPL(mtd_lock);
1823
1824int mtd_unlock(struct mtd_info *mtd, loff_t ofs, uint64_t len)
1825{
Miquel Raynal46b58892020-01-14 10:09:52 +01001826 struct mtd_info *master = mtd_get_master(mtd);
1827
1828 if (!master->_unlock)
Artem Bityutskiy8273a0c2012-02-03 14:34:14 +02001829 return -EOPNOTSUPP;
Brian Norris0c2b4e22014-07-21 19:06:27 -07001830 if (ofs < 0 || ofs >= mtd->size || len > mtd->size - ofs)
Artem Bityutskiy8273a0c2012-02-03 14:34:14 +02001831 return -EINVAL;
Artem Bityutskiybcb1d232012-02-06 13:27:43 +02001832 if (!len)
1833 return 0;
Miquel Raynal46b58892020-01-14 10:09:52 +01001834 return master->_unlock(master, mtd_get_master_ofs(mtd, ofs), len);
Artem Bityutskiy8273a0c2012-02-03 14:34:14 +02001835}
1836EXPORT_SYMBOL_GPL(mtd_unlock);
1837
1838int mtd_is_locked(struct mtd_info *mtd, loff_t ofs, uint64_t len)
1839{
Miquel Raynal46b58892020-01-14 10:09:52 +01001840 struct mtd_info *master = mtd_get_master(mtd);
1841
1842 if (!master->_is_locked)
Artem Bityutskiy8273a0c2012-02-03 14:34:14 +02001843 return -EOPNOTSUPP;
Brian Norris0c2b4e22014-07-21 19:06:27 -07001844 if (ofs < 0 || ofs >= mtd->size || len > mtd->size - ofs)
Artem Bityutskiy8273a0c2012-02-03 14:34:14 +02001845 return -EINVAL;
Artem Bityutskiybcb1d232012-02-06 13:27:43 +02001846 if (!len)
1847 return 0;
Miquel Raynal46b58892020-01-14 10:09:52 +01001848 return master->_is_locked(master, mtd_get_master_ofs(mtd, ofs), len);
Artem Bityutskiy8273a0c2012-02-03 14:34:14 +02001849}
1850EXPORT_SYMBOL_GPL(mtd_is_locked);
1851
Ezequiel Garcia8471bb72014-05-21 19:06:12 -03001852int mtd_block_isreserved(struct mtd_info *mtd, loff_t ofs)
Artem Bityutskiy8273a0c2012-02-03 14:34:14 +02001853{
Miquel Raynal46b58892020-01-14 10:09:52 +01001854 struct mtd_info *master = mtd_get_master(mtd);
1855
Brian Norris0c2b4e22014-07-21 19:06:27 -07001856 if (ofs < 0 || ofs >= mtd->size)
Artem Bityutskiy8273a0c2012-02-03 14:34:14 +02001857 return -EINVAL;
Miquel Raynal46b58892020-01-14 10:09:52 +01001858 if (!master->_block_isreserved)
Ezequiel Garcia8471bb72014-05-21 19:06:12 -03001859 return 0;
Miquel Raynal46b58892020-01-14 10:09:52 +01001860 return master->_block_isreserved(master, mtd_get_master_ofs(mtd, ofs));
Ezequiel Garcia8471bb72014-05-21 19:06:12 -03001861}
1862EXPORT_SYMBOL_GPL(mtd_block_isreserved);
1863
1864int mtd_block_isbad(struct mtd_info *mtd, loff_t ofs)
1865{
Miquel Raynal46b58892020-01-14 10:09:52 +01001866 struct mtd_info *master = mtd_get_master(mtd);
1867
Brian Norris0c2b4e22014-07-21 19:06:27 -07001868 if (ofs < 0 || ofs >= mtd->size)
Ezequiel Garcia8471bb72014-05-21 19:06:12 -03001869 return -EINVAL;
Miquel Raynal46b58892020-01-14 10:09:52 +01001870 if (!master->_block_isbad)
Ezequiel Garcia8471bb72014-05-21 19:06:12 -03001871 return 0;
Miquel Raynal46b58892020-01-14 10:09:52 +01001872 return master->_block_isbad(master, mtd_get_master_ofs(mtd, ofs));
Artem Bityutskiy8273a0c2012-02-03 14:34:14 +02001873}
1874EXPORT_SYMBOL_GPL(mtd_block_isbad);
1875
1876int mtd_block_markbad(struct mtd_info *mtd, loff_t ofs)
1877{
Miquel Raynal46b58892020-01-14 10:09:52 +01001878 struct mtd_info *master = mtd_get_master(mtd);
1879 int ret;
1880
1881 if (!master->_block_markbad)
Artem Bityutskiy8273a0c2012-02-03 14:34:14 +02001882 return -EOPNOTSUPP;
Brian Norris0c2b4e22014-07-21 19:06:27 -07001883 if (ofs < 0 || ofs >= mtd->size)
Artem Bityutskiy8273a0c2012-02-03 14:34:14 +02001884 return -EINVAL;
Artem Bityutskiy664addc2012-02-03 18:13:23 +02001885 if (!(mtd->flags & MTD_WRITEABLE))
1886 return -EROFS;
Miquel Raynal46b58892020-01-14 10:09:52 +01001887
1888 ret = master->_block_markbad(master, mtd_get_master_ofs(mtd, ofs));
1889 if (ret)
1890 return ret;
1891
1892 while (mtd->parent) {
1893 mtd->ecc_stats.badblocks++;
1894 mtd = mtd->parent;
1895 }
1896
1897 return 0;
Artem Bityutskiy8273a0c2012-02-03 14:34:14 +02001898}
1899EXPORT_SYMBOL_GPL(mtd_block_markbad);
1900
1901/*
Artem Bityutskiy52b02032011-12-30 15:57:25 +02001902 * default_mtd_writev - the default writev method
1903 * @mtd: mtd device description object pointer
1904 * @vecs: the vectors to write
1905 * @count: count of vectors in @vecs
1906 * @to: the MTD device offset to write to
1907 * @retlen: on exit contains the count of bytes written to the MTD device.
1908 *
1909 * This function returns zero in case of success and a negative error code in
1910 * case of failure.
Linus Torvalds1da177e2005-04-16 15:20:36 -07001911 */
Artem Bityutskiy1dbebd32011-12-30 16:23:41 +02001912static int default_mtd_writev(struct mtd_info *mtd, const struct kvec *vecs,
1913 unsigned long count, loff_t to, size_t *retlen)
Linus Torvalds1da177e2005-04-16 15:20:36 -07001914{
1915 unsigned long i;
1916 size_t totlen = 0, thislen;
1917 int ret = 0;
1918
Artem Bityutskiy52b02032011-12-30 15:57:25 +02001919 for (i = 0; i < count; i++) {
1920 if (!vecs[i].iov_len)
1921 continue;
1922 ret = mtd_write(mtd, to, vecs[i].iov_len, &thislen,
1923 vecs[i].iov_base);
1924 totlen += thislen;
1925 if (ret || thislen != vecs[i].iov_len)
1926 break;
1927 to += vecs[i].iov_len;
Linus Torvalds1da177e2005-04-16 15:20:36 -07001928 }
Artem Bityutskiy52b02032011-12-30 15:57:25 +02001929 *retlen = totlen;
Linus Torvalds1da177e2005-04-16 15:20:36 -07001930 return ret;
1931}
Artem Bityutskiy1dbebd32011-12-30 16:23:41 +02001932
1933/*
1934 * mtd_writev - the vector-based MTD write method
1935 * @mtd: mtd device description object pointer
1936 * @vecs: the vectors to write
1937 * @count: count of vectors in @vecs
1938 * @to: the MTD device offset to write to
1939 * @retlen: on exit contains the count of bytes written to the MTD device.
1940 *
1941 * This function returns zero in case of success and a negative error code in
1942 * case of failure.
1943 */
1944int mtd_writev(struct mtd_info *mtd, const struct kvec *vecs,
1945 unsigned long count, loff_t to, size_t *retlen)
1946{
Miquel Raynal46b58892020-01-14 10:09:52 +01001947 struct mtd_info *master = mtd_get_master(mtd);
1948
Artem Bityutskiy1dbebd32011-12-30 16:23:41 +02001949 *retlen = 0;
Artem Bityutskiy664addc2012-02-03 18:13:23 +02001950 if (!(mtd->flags & MTD_WRITEABLE))
1951 return -EROFS;
Miquel Raynal46b58892020-01-14 10:09:52 +01001952
1953 if (!master->_writev)
Artem Bityutskiy1dbebd32011-12-30 16:23:41 +02001954 return default_mtd_writev(mtd, vecs, count, to, retlen);
Miquel Raynal46b58892020-01-14 10:09:52 +01001955
1956 return master->_writev(master, vecs, count,
1957 mtd_get_master_ofs(mtd, to), retlen);
Artem Bityutskiy1dbebd32011-12-30 16:23:41 +02001958}
1959EXPORT_SYMBOL_GPL(mtd_writev);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001960
Grant Erickson33b53712011-04-08 08:51:32 -07001961/**
1962 * mtd_kmalloc_up_to - allocate a contiguous buffer up to the specified size
Artem Bityutskiy52b02032011-12-30 15:57:25 +02001963 * @mtd: mtd device description object pointer
1964 * @size: a pointer to the ideal or maximum size of the allocation, points
Grant Erickson33b53712011-04-08 08:51:32 -07001965 * to the actual allocation size on success.
1966 *
1967 * This routine attempts to allocate a contiguous kernel buffer up to
1968 * the specified size, backing off the size of the request exponentially
1969 * until the request succeeds or until the allocation size falls below
1970 * the system page size. This attempts to make sure it does not adversely
1971 * impact system performance, so when allocating more than one page, we
Linus Torvaldscaf49192012-12-10 10:51:16 -08001972 * ask the memory allocator to avoid re-trying, swapping, writing back
1973 * or performing I/O.
Grant Erickson33b53712011-04-08 08:51:32 -07001974 *
1975 * Note, this function also makes sure that the allocated buffer is aligned to
1976 * the MTD device's min. I/O unit, i.e. the "mtd->writesize" value.
1977 *
1978 * This is called, for example by mtd_{read,write} and jffs2_scan_medium,
1979 * to handle smaller (i.e. degraded) buffer allocations under low- or
1980 * fragmented-memory situations where such reduced allocations, from a
1981 * requested ideal, are allowed.
1982 *
1983 * Returns a pointer to the allocated buffer on success; otherwise, NULL.
1984 */
1985void *mtd_kmalloc_up_to(const struct mtd_info *mtd, size_t *size)
1986{
Mel Gormand0164ad2015-11-06 16:28:21 -08001987 gfp_t flags = __GFP_NOWARN | __GFP_DIRECT_RECLAIM | __GFP_NORETRY;
Grant Erickson33b53712011-04-08 08:51:32 -07001988 size_t min_alloc = max_t(size_t, mtd->writesize, PAGE_SIZE);
1989 void *kbuf;
1990
1991 *size = min_t(size_t, *size, KMALLOC_MAX_SIZE);
1992
1993 while (*size > min_alloc) {
1994 kbuf = kmalloc(*size, flags);
1995 if (kbuf)
1996 return kbuf;
1997
1998 *size >>= 1;
1999 *size = ALIGN(*size, mtd->writesize);
2000 }
2001
2002 /*
2003 * For the last resort allocation allow 'kmalloc()' to do all sorts of
2004 * things (write-back, dropping caches, etc) by using GFP_KERNEL.
2005 */
2006 return kmalloc(*size, GFP_KERNEL);
2007}
Grant Erickson33b53712011-04-08 08:51:32 -07002008EXPORT_SYMBOL_GPL(mtd_kmalloc_up_to);
Linus Torvalds1da177e2005-04-16 15:20:36 -07002009
Pavel Machek2d2dce02006-03-31 02:29:49 -08002010#ifdef CONFIG_PROC_FS
2011
Linus Torvalds1da177e2005-04-16 15:20:36 -07002012/*====================================================================*/
Linus Torvalds1da177e2005-04-16 15:20:36 -07002013/* Support for /proc/mtd */
2014
Alexey Dobriyan447d9bd2011-05-13 23:34:19 +03002015static int mtd_proc_show(struct seq_file *m, void *v)
Linus Torvalds1da177e2005-04-16 15:20:36 -07002016{
Ben Hutchingsf1332ba2010-01-29 20:57:11 +00002017 struct mtd_info *mtd;
Linus Torvalds1da177e2005-04-16 15:20:36 -07002018
Alexey Dobriyan447d9bd2011-05-13 23:34:19 +03002019 seq_puts(m, "dev: size erasesize name\n");
Ingo Molnar48b19262006-03-31 02:29:41 -08002020 mutex_lock(&mtd_table_mutex);
Ben Hutchingsf1332ba2010-01-29 20:57:11 +00002021 mtd_for_each_device(mtd) {
Alexey Dobriyan447d9bd2011-05-13 23:34:19 +03002022 seq_printf(m, "mtd%d: %8.8llx %8.8x \"%s\"\n",
2023 mtd->index, (unsigned long long)mtd->size,
2024 mtd->erasesize, mtd->name);
Wanlong Gaod5ca5122011-05-20 21:14:30 +08002025 }
Ingo Molnar48b19262006-03-31 02:29:41 -08002026 mutex_unlock(&mtd_table_mutex);
Wanlong Gaod5ca5122011-05-20 21:14:30 +08002027 return 0;
Linus Torvalds1da177e2005-04-16 15:20:36 -07002028}
Kevin Cernekee45b09072009-04-04 11:03:04 -07002029#endif /* CONFIG_PROC_FS */
2030
Linus Torvalds1da177e2005-04-16 15:20:36 -07002031/*====================================================================*/
2032/* Init code */
2033
Steve Longerbeam445caaa2016-08-04 19:31:15 +05302034static struct backing_dev_info * __init mtd_bdi_init(char *name)
Jens Axboe0661b1a2010-04-27 09:49:47 +02002035{
Steve Longerbeam445caaa2016-08-04 19:31:15 +05302036 struct backing_dev_info *bdi;
Jens Axboe0661b1a2010-04-27 09:49:47 +02002037 int ret;
2038
Jan Karafa060522017-04-12 12:24:37 +02002039 bdi = bdi_alloc(GFP_KERNEL);
Steve Longerbeam445caaa2016-08-04 19:31:15 +05302040 if (!bdi)
2041 return ERR_PTR(-ENOMEM);
Jens Axboe0661b1a2010-04-27 09:49:47 +02002042
Jan Karafa060522017-04-12 12:24:37 +02002043 bdi->name = name;
2044 /*
2045 * We put '-0' suffix to the name to get the same name format as we
2046 * used to get. Since this is called only once, we get a unique name.
2047 */
Jan Kara7c4cc302017-04-12 12:24:49 +02002048 ret = bdi_register(bdi, "%.28s-0", name);
Jens Axboe0661b1a2010-04-27 09:49:47 +02002049 if (ret)
Jan Karafa060522017-04-12 12:24:37 +02002050 bdi_put(bdi);
Jens Axboe0661b1a2010-04-27 09:49:47 +02002051
Steve Longerbeam445caaa2016-08-04 19:31:15 +05302052 return ret ? ERR_PTR(ret) : bdi;
Jens Axboe0661b1a2010-04-27 09:49:47 +02002053}
2054
Artem Bityutskiy93e56212013-03-15 12:56:05 +02002055static struct proc_dir_entry *proc_mtd;
2056
Linus Torvalds1da177e2005-04-16 15:20:36 -07002057static int __init init_mtd(void)
2058{
David Woodhouse15bce402009-04-05 07:40:58 -07002059 int ret;
Kevin Cernekee694bb7f2009-04-03 13:00:45 -07002060
Jens Axboe0661b1a2010-04-27 09:49:47 +02002061 ret = class_register(&mtd_class);
2062 if (ret)
2063 goto err_reg;
2064
Steve Longerbeam445caaa2016-08-04 19:31:15 +05302065 mtd_bdi = mtd_bdi_init("mtd");
2066 if (IS_ERR(mtd_bdi)) {
2067 ret = PTR_ERR(mtd_bdi);
Christoph Hellwigb4caecd2015-01-14 10:42:32 +01002068 goto err_bdi;
Steve Longerbeam445caaa2016-08-04 19:31:15 +05302069 }
Jens Axboe0661b1a2010-04-27 09:49:47 +02002070
Christoph Hellwig3f3942a2018-05-15 15:57:23 +02002071 proc_mtd = proc_create_single("mtd", 0, NULL, mtd_proc_show);
Artem Bityutskiy93e56212013-03-15 12:56:05 +02002072
Artem Bityutskiy660685d2013-03-14 13:27:40 +02002073 ret = init_mtdchar();
2074 if (ret)
2075 goto out_procfs;
2076
Mario Rugieroe8e3edb2017-05-29 08:38:41 -03002077 dfs_dir_mtd = debugfs_create_dir("mtd", NULL);
2078
Linus Torvalds1da177e2005-04-16 15:20:36 -07002079 return 0;
Jens Axboe0661b1a2010-04-27 09:49:47 +02002080
Artem Bityutskiy660685d2013-03-14 13:27:40 +02002081out_procfs:
2082 if (proc_mtd)
2083 remove_proc_entry("mtd", NULL);
Jan Karafa060522017-04-12 12:24:37 +02002084 bdi_put(mtd_bdi);
Christoph Hellwigb4caecd2015-01-14 10:42:32 +01002085err_bdi:
Jens Axboe0661b1a2010-04-27 09:49:47 +02002086 class_unregister(&mtd_class);
2087err_reg:
2088 pr_err("Error registering mtd class or bdi: %d\n", ret);
2089 return ret;
Linus Torvalds1da177e2005-04-16 15:20:36 -07002090}
2091
2092static void __exit cleanup_mtd(void)
2093{
Mario Rugieroe8e3edb2017-05-29 08:38:41 -03002094 debugfs_remove_recursive(dfs_dir_mtd);
Artem Bityutskiy660685d2013-03-14 13:27:40 +02002095 cleanup_mtdchar();
Wanlong Gaod5ca5122011-05-20 21:14:30 +08002096 if (proc_mtd)
Artem Bityutskiy93e56212013-03-15 12:56:05 +02002097 remove_proc_entry("mtd", NULL);
David Woodhouse15bce402009-04-05 07:40:58 -07002098 class_unregister(&mtd_class);
Jan Karafa060522017-04-12 12:24:37 +02002099 bdi_put(mtd_bdi);
Johannes Thumshirn35667b92015-07-08 17:15:34 +02002100 idr_destroy(&mtd_idr);
Linus Torvalds1da177e2005-04-16 15:20:36 -07002101}
2102
2103module_init(init_mtd);
2104module_exit(cleanup_mtd);
2105
Linus Torvalds1da177e2005-04-16 15:20:36 -07002106MODULE_LICENSE("GPL");
2107MODULE_AUTHOR("David Woodhouse <dwmw2@infradead.org>");
2108MODULE_DESCRIPTION("Core MTD registration and access routines");