blob: d4e0a0f6732ae60b6358a13b1282327c41ffe020 [file] [log] [blame]
Kamal Dasudd1aa252015-06-09 15:36:20 -04001/*
2 * Copyright (C) 2014 Broadcom Corporation
3 *
4 * This program is free software; you can redistribute it and/or
5 * modify it under the terms of the GNU General Public License as
6 * published by the Free Software Foundation version 2.
7 *
8 * This program is distributed "as is" WITHOUT ANY WARRANTY of any
9 * kind, whether express or implied; without even the implied warranty
10 * of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
11 * GNU General Public License for more details.
12 */
13
14#include <linux/clk.h>
15#include <linux/delay.h>
16#include <linux/device.h>
17#include <linux/i2c.h>
18#include <linux/interrupt.h>
19#include <linux/io.h>
20#include <linux/kernel.h>
21#include <linux/module.h>
22#include <linux/platform_device.h>
23#include <linux/sched.h>
24#include <linux/slab.h>
25#include <linux/version.h>
26
27#define N_DATA_REGS 8
Kamal Dasudd1aa252015-06-09 15:36:20 -040028
Kamal Dasue2e5a2c2015-12-16 15:49:09 -050029/*
30 * PER_I2C/BSC count register mask depends on 1 byte/4 byte data register
31 * size. Cable modem and DSL SoCs with Peripheral i2c cores use 1 byte per
32 * data register whereas STB SoCs use 4 byte per data register transfer,
33 * account for this difference in total count per transaction and mask to
34 * use.
35 */
36#define BSC_CNT_REG1_MASK(nb) (nb == 1 ? GENMASK(3, 0) : GENMASK(5, 0))
37#define BSC_CNT_REG1_SHIFT 0
Kamal Dasudd1aa252015-06-09 15:36:20 -040038
39/* BSC CTL register field definitions */
40#define BSC_CTL_REG_DTF_MASK 0x00000003
41#define BSC_CTL_REG_SCL_SEL_MASK 0x00000030
42#define BSC_CTL_REG_SCL_SEL_SHIFT 4
43#define BSC_CTL_REG_INT_EN_MASK 0x00000040
44#define BSC_CTL_REG_INT_EN_SHIFT 6
45#define BSC_CTL_REG_DIV_CLK_MASK 0x00000080
46
Kamal Dasue2e5a2c2015-12-16 15:49:09 -050047/* BSC_IIC_ENABLE r/w enable and interrupt field definitions */
Kamal Dasudd1aa252015-06-09 15:36:20 -040048#define BSC_IIC_EN_RESTART_MASK 0x00000040
49#define BSC_IIC_EN_NOSTART_MASK 0x00000020
50#define BSC_IIC_EN_NOSTOP_MASK 0x00000010
51#define BSC_IIC_EN_NOACK_MASK 0x00000004
52#define BSC_IIC_EN_INTRP_MASK 0x00000002
53#define BSC_IIC_EN_ENABLE_MASK 0x00000001
54
55/* BSC_CTLHI control register field definitions */
56#define BSC_CTLHI_REG_INPUT_SWITCHING_LEVEL_MASK 0x00000080
57#define BSC_CTLHI_REG_DATAREG_SIZE_MASK 0x00000040
58#define BSC_CTLHI_REG_IGNORE_ACK_MASK 0x00000002
59#define BSC_CTLHI_REG_WAIT_DIS_MASK 0x00000001
60
61#define I2C_TIMEOUT 100 /* msecs */
62
63/* Condition mask used for non combined transfer */
64#define COND_RESTART BSC_IIC_EN_RESTART_MASK
65#define COND_NOSTART BSC_IIC_EN_NOSTART_MASK
66#define COND_NOSTOP BSC_IIC_EN_NOSTOP_MASK
67#define COND_START_STOP (COND_RESTART | COND_NOSTART | COND_NOSTOP)
68
69/* BSC data transfer direction */
70#define DTF_WR_MASK 0x00000000
71#define DTF_RD_MASK 0x00000001
72/* BSC data transfer direction combined format */
73#define DTF_RD_WR_MASK 0x00000002
74#define DTF_WR_RD_MASK 0x00000003
75
76#define INT_ENABLE true
77#define INT_DISABLE false
78
79/* BSC block register map structure to cache fields to be written */
80struct bsc_regs {
81 u32 chip_address; /* slave address */
82 u32 data_in[N_DATA_REGS]; /* tx data buffer*/
83 u32 cnt_reg; /* rx/tx data length */
84 u32 ctl_reg; /* control register */
85 u32 iic_enable; /* xfer enable and status */
86 u32 data_out[N_DATA_REGS]; /* rx data buffer */
87 u32 ctlhi_reg; /* more control fields */
88 u32 scl_param; /* reserved */
89};
90
91struct bsc_clk_param {
92 u32 hz;
93 u32 scl_mask;
94 u32 div_mask;
95};
96
97enum bsc_xfer_cmd {
98 CMD_WR,
99 CMD_RD,
100 CMD_WR_NOACK,
101 CMD_RD_NOACK,
102};
103
104static char const *cmd_string[] = {
105 [CMD_WR] = "WR",
106 [CMD_RD] = "RD",
107 [CMD_WR_NOACK] = "WR NOACK",
108 [CMD_RD_NOACK] = "RD NOACK",
109};
110
111enum bus_speeds {
112 SPD_375K,
113 SPD_390K,
114 SPD_187K,
115 SPD_200K,
116 SPD_93K,
117 SPD_97K,
118 SPD_46K,
119 SPD_50K
120};
121
122static const struct bsc_clk_param bsc_clk[] = {
123 [SPD_375K] = {
124 .hz = 375000,
125 .scl_mask = SPD_375K << BSC_CTL_REG_SCL_SEL_SHIFT,
126 .div_mask = 0
127 },
128 [SPD_390K] = {
129 .hz = 390000,
130 .scl_mask = SPD_390K << BSC_CTL_REG_SCL_SEL_SHIFT,
131 .div_mask = 0
132 },
133 [SPD_187K] = {
134 .hz = 187500,
135 .scl_mask = SPD_187K << BSC_CTL_REG_SCL_SEL_SHIFT,
136 .div_mask = 0
137 },
138 [SPD_200K] = {
139 .hz = 200000,
140 .scl_mask = SPD_200K << BSC_CTL_REG_SCL_SEL_SHIFT,
141 .div_mask = 0
142 },
143 [SPD_93K] = {
144 .hz = 93750,
145 .scl_mask = SPD_375K << BSC_CTL_REG_SCL_SEL_SHIFT,
146 .div_mask = BSC_CTL_REG_DIV_CLK_MASK
147 },
148 [SPD_97K] = {
149 .hz = 97500,
150 .scl_mask = SPD_390K << BSC_CTL_REG_SCL_SEL_SHIFT,
151 .div_mask = BSC_CTL_REG_DIV_CLK_MASK
152 },
153 [SPD_46K] = {
154 .hz = 46875,
155 .scl_mask = SPD_187K << BSC_CTL_REG_SCL_SEL_SHIFT,
156 .div_mask = BSC_CTL_REG_DIV_CLK_MASK
157 },
158 [SPD_50K] = {
159 .hz = 50000,
160 .scl_mask = SPD_200K << BSC_CTL_REG_SCL_SEL_SHIFT,
161 .div_mask = BSC_CTL_REG_DIV_CLK_MASK
162 }
163};
164
165struct brcmstb_i2c_dev {
166 struct device *device;
167 void __iomem *base;
Kamal Dasudd1aa252015-06-09 15:36:20 -0400168 int irq;
169 struct bsc_regs *bsc_regmap;
170 struct i2c_adapter adapter;
171 struct completion done;
Kamal Dasudd1aa252015-06-09 15:36:20 -0400172 u32 clk_freq_hz;
Kamal Dasue2e5a2c2015-12-16 15:49:09 -0500173 int data_regsz;
Kamal Dasudd1aa252015-06-09 15:36:20 -0400174};
175
176/* register accessors for both be and le cpu arch */
177#ifdef CONFIG_CPU_BIG_ENDIAN
178#define __bsc_readl(_reg) ioread32be(_reg)
179#define __bsc_writel(_val, _reg) iowrite32be(_val, _reg)
180#else
181#define __bsc_readl(_reg) ioread32(_reg)
182#define __bsc_writel(_val, _reg) iowrite32(_val, _reg)
183#endif
184
185#define bsc_readl(_dev, _reg) \
186 __bsc_readl(_dev->base + offsetof(struct bsc_regs, _reg))
187
188#define bsc_writel(_dev, _val, _reg) \
189 __bsc_writel(_val, _dev->base + offsetof(struct bsc_regs, _reg))
190
Kamal Dasue2e5a2c2015-12-16 15:49:09 -0500191static inline int brcmstb_i2c_get_xfersz(struct brcmstb_i2c_dev *dev)
192{
193 return (N_DATA_REGS * dev->data_regsz);
194}
195
196static inline int brcmstb_i2c_get_data_regsz(struct brcmstb_i2c_dev *dev)
197{
198 return dev->data_regsz;
199}
200
Kamal Dasudd1aa252015-06-09 15:36:20 -0400201static void brcmstb_i2c_enable_disable_irq(struct brcmstb_i2c_dev *dev,
202 bool int_en)
203{
204
205 if (int_en)
206 /* Enable BSC CTL interrupt line */
207 dev->bsc_regmap->ctl_reg |= BSC_CTL_REG_INT_EN_MASK;
208 else
209 /* Disable BSC CTL interrupt line */
210 dev->bsc_regmap->ctl_reg &= ~BSC_CTL_REG_INT_EN_MASK;
211
212 barrier();
213 bsc_writel(dev, dev->bsc_regmap->ctl_reg, ctl_reg);
214}
215
216static irqreturn_t brcmstb_i2c_isr(int irq, void *devid)
217{
218 struct brcmstb_i2c_dev *dev = devid;
219 u32 status_bsc_ctl = bsc_readl(dev, ctl_reg);
220 u32 status_iic_intrp = bsc_readl(dev, iic_enable);
221
222 dev_dbg(dev->device, "isr CTL_REG %x IIC_EN %x\n",
223 status_bsc_ctl, status_iic_intrp);
224
225 if (!(status_bsc_ctl & BSC_CTL_REG_INT_EN_MASK))
226 return IRQ_NONE;
227
228 brcmstb_i2c_enable_disable_irq(dev, INT_DISABLE);
Daniel Wagnerfea03a62016-08-03 14:03:10 +0200229 complete(&dev->done);
Kamal Dasudd1aa252015-06-09 15:36:20 -0400230
231 dev_dbg(dev->device, "isr handled");
232 return IRQ_HANDLED;
233}
234
235/* Wait for device to be ready */
236static int brcmstb_i2c_wait_if_busy(struct brcmstb_i2c_dev *dev)
237{
238 unsigned long timeout = jiffies + msecs_to_jiffies(I2C_TIMEOUT);
239
240 while ((bsc_readl(dev, iic_enable) & BSC_IIC_EN_INTRP_MASK)) {
241 if (time_after(jiffies, timeout))
242 return -ETIMEDOUT;
243 cpu_relax();
244 }
245 return 0;
246}
247
248/* i2c xfer completion function, handles both irq and polling mode */
249static int brcmstb_i2c_wait_for_completion(struct brcmstb_i2c_dev *dev)
250{
251 int ret = 0;
252 unsigned long timeout = msecs_to_jiffies(I2C_TIMEOUT);
253
254 if (dev->irq >= 0) {
255 if (!wait_for_completion_timeout(&dev->done, timeout))
256 ret = -ETIMEDOUT;
257 } else {
258 /* we are in polling mode */
259 u32 bsc_intrp;
260 unsigned long time_left = jiffies + timeout;
261
262 do {
263 bsc_intrp = bsc_readl(dev, iic_enable) &
264 BSC_IIC_EN_INTRP_MASK;
265 if (time_after(jiffies, time_left)) {
266 ret = -ETIMEDOUT;
267 break;
268 }
269 cpu_relax();
270 } while (!bsc_intrp);
271 }
272
273 if (dev->irq < 0 || ret == -ETIMEDOUT)
274 brcmstb_i2c_enable_disable_irq(dev, INT_DISABLE);
275
276 return ret;
277}
278
279/* Set xfer START/STOP conditions for subsequent transfer */
280static void brcmstb_set_i2c_start_stop(struct brcmstb_i2c_dev *dev,
281 u32 cond_flag)
282{
283 u32 regval = dev->bsc_regmap->iic_enable;
284
285 dev->bsc_regmap->iic_enable = (regval & ~COND_START_STOP) | cond_flag;
286}
287
288/* Send I2C request check completion */
289static int brcmstb_send_i2c_cmd(struct brcmstb_i2c_dev *dev,
290 enum bsc_xfer_cmd cmd)
291{
292 int rc = 0;
293 struct bsc_regs *pi2creg = dev->bsc_regmap;
294
295 /* Make sure the hardware is ready */
296 rc = brcmstb_i2c_wait_if_busy(dev);
297 if (rc < 0)
298 return rc;
299
300 /* only if we are in interrupt mode */
301 if (dev->irq >= 0)
302 reinit_completion(&dev->done);
303
304 /* enable BSC CTL interrupt line */
305 brcmstb_i2c_enable_disable_irq(dev, INT_ENABLE);
306
307 /* initiate transfer by setting iic_enable */
308 pi2creg->iic_enable |= BSC_IIC_EN_ENABLE_MASK;
309 bsc_writel(dev, pi2creg->iic_enable, iic_enable);
310
311 /* Wait for transaction to finish or timeout */
312 rc = brcmstb_i2c_wait_for_completion(dev);
313 if (rc) {
314 dev_dbg(dev->device, "intr timeout for cmd %s\n",
315 cmd_string[cmd]);
316 goto cmd_out;
317 }
318
319 if ((CMD_RD || CMD_WR) &&
320 bsc_readl(dev, iic_enable) & BSC_IIC_EN_NOACK_MASK) {
321 rc = -EREMOTEIO;
322 dev_dbg(dev->device, "controller received NOACK intr for %s\n",
323 cmd_string[cmd]);
324 }
325
326cmd_out:
327 bsc_writel(dev, 0, cnt_reg);
328 bsc_writel(dev, 0, iic_enable);
329
330 return rc;
331}
332
333/* Actual data transfer through the BSC master */
334static int brcmstb_i2c_xfer_bsc_data(struct brcmstb_i2c_dev *dev,
335 u8 *buf, unsigned int len,
336 struct i2c_msg *pmsg)
337{
Kamal Dasue2e5a2c2015-12-16 15:49:09 -0500338 int cnt, byte, i, rc;
Kamal Dasudd1aa252015-06-09 15:36:20 -0400339 enum bsc_xfer_cmd cmd;
340 u32 ctl_reg;
341 struct bsc_regs *pi2creg = dev->bsc_regmap;
342 int no_ack = pmsg->flags & I2C_M_IGNORE_NAK;
Kamal Dasue2e5a2c2015-12-16 15:49:09 -0500343 int data_regsz = brcmstb_i2c_get_data_regsz(dev);
Kamal Dasudd1aa252015-06-09 15:36:20 -0400344
345 /* see if the transaction needs to check NACK conditions */
Jaedon Shin94a0b0b2016-07-15 12:45:09 +0900346 if (no_ack) {
Kamal Dasudd1aa252015-06-09 15:36:20 -0400347 cmd = (pmsg->flags & I2C_M_RD) ? CMD_RD_NOACK
348 : CMD_WR_NOACK;
349 pi2creg->ctlhi_reg |= BSC_CTLHI_REG_IGNORE_ACK_MASK;
350 } else {
351 cmd = (pmsg->flags & I2C_M_RD) ? CMD_RD : CMD_WR;
352 pi2creg->ctlhi_reg &= ~BSC_CTLHI_REG_IGNORE_ACK_MASK;
353 }
354 bsc_writel(dev, pi2creg->ctlhi_reg, ctlhi_reg);
355
356 /* set data transfer direction */
357 ctl_reg = pi2creg->ctl_reg & ~BSC_CTL_REG_DTF_MASK;
358 if (cmd == CMD_WR || cmd == CMD_WR_NOACK)
359 pi2creg->ctl_reg = ctl_reg | DTF_WR_MASK;
360 else
361 pi2creg->ctl_reg = ctl_reg | DTF_RD_MASK;
362
363 /* set the read/write length */
Kamal Dasue2e5a2c2015-12-16 15:49:09 -0500364 bsc_writel(dev, BSC_CNT_REG1_MASK(data_regsz) &
365 (len << BSC_CNT_REG1_SHIFT), cnt_reg);
Kamal Dasudd1aa252015-06-09 15:36:20 -0400366
367 /* Write data into data_in register */
Kamal Dasue2e5a2c2015-12-16 15:49:09 -0500368
Kamal Dasudd1aa252015-06-09 15:36:20 -0400369 if (cmd == CMD_WR || cmd == CMD_WR_NOACK) {
Kamal Dasue2e5a2c2015-12-16 15:49:09 -0500370 for (cnt = 0, i = 0; cnt < len; cnt += data_regsz, i++) {
Kamal Dasudd1aa252015-06-09 15:36:20 -0400371 u32 word = 0;
372
Kamal Dasue2e5a2c2015-12-16 15:49:09 -0500373 for (byte = 0; byte < data_regsz; byte++) {
374 word >>= BITS_PER_BYTE;
Kamal Dasudd1aa252015-06-09 15:36:20 -0400375 if ((cnt + byte) < len)
Kamal Dasue2e5a2c2015-12-16 15:49:09 -0500376 word |= buf[cnt + byte] <<
377 (BITS_PER_BYTE * (data_regsz - 1));
Kamal Dasudd1aa252015-06-09 15:36:20 -0400378 }
Kamal Dasue2e5a2c2015-12-16 15:49:09 -0500379 bsc_writel(dev, word, data_in[i]);
Kamal Dasudd1aa252015-06-09 15:36:20 -0400380 }
381 }
382
383 /* Initiate xfer, the function will return on completion */
384 rc = brcmstb_send_i2c_cmd(dev, cmd);
385
386 if (rc != 0) {
387 dev_dbg(dev->device, "%s failure", cmd_string[cmd]);
388 return rc;
389 }
390
Kamal Dasue2e5a2c2015-12-16 15:49:09 -0500391 /* Read data from data_out register */
Kamal Dasudd1aa252015-06-09 15:36:20 -0400392 if (cmd == CMD_RD || cmd == CMD_RD_NOACK) {
Kamal Dasue2e5a2c2015-12-16 15:49:09 -0500393 for (cnt = 0, i = 0; cnt < len; cnt += data_regsz, i++) {
394 u32 data = bsc_readl(dev, data_out[i]);
Kamal Dasudd1aa252015-06-09 15:36:20 -0400395
Kamal Dasue2e5a2c2015-12-16 15:49:09 -0500396 for (byte = 0; byte < data_regsz &&
Kamal Dasudd1aa252015-06-09 15:36:20 -0400397 (byte + cnt) < len; byte++) {
398 buf[cnt + byte] = data & 0xff;
Kamal Dasue2e5a2c2015-12-16 15:49:09 -0500399 data >>= BITS_PER_BYTE;
Kamal Dasudd1aa252015-06-09 15:36:20 -0400400 }
401 }
402 }
403
404 return 0;
405}
406
407/* Write a single byte of data to the i2c bus */
408static int brcmstb_i2c_write_data_byte(struct brcmstb_i2c_dev *dev,
409 u8 *buf, unsigned int nak_expected)
410{
411 enum bsc_xfer_cmd cmd = nak_expected ? CMD_WR : CMD_WR_NOACK;
412
413 bsc_writel(dev, 1, cnt_reg);
414 bsc_writel(dev, *buf, data_in);
415
416 return brcmstb_send_i2c_cmd(dev, cmd);
417}
418
419/* Send i2c address */
420static int brcmstb_i2c_do_addr(struct brcmstb_i2c_dev *dev,
421 struct i2c_msg *msg)
422{
423 unsigned char addr;
424
425 if (msg->flags & I2C_M_TEN) {
426 /* First byte is 11110XX0 where XX is upper 2 bits */
427 addr = 0xF0 | ((msg->addr & 0x300) >> 7);
428 bsc_writel(dev, addr, chip_address);
429
430 /* Second byte is the remaining 8 bits */
431 addr = msg->addr & 0xFF;
432 if (brcmstb_i2c_write_data_byte(dev, &addr, 0) < 0)
433 return -EREMOTEIO;
434
435 if (msg->flags & I2C_M_RD) {
436 /* For read, send restart without stop condition */
437 brcmstb_set_i2c_start_stop(dev, COND_RESTART
438 | COND_NOSTOP);
439 /* Then re-send the first byte with the read bit set */
440 addr = 0xF0 | ((msg->addr & 0x300) >> 7) | 0x01;
441 if (brcmstb_i2c_write_data_byte(dev, &addr, 0) < 0)
442 return -EREMOTEIO;
443
444 }
445 } else {
Wolfram Sangfa5ce472016-04-03 20:44:49 +0200446 addr = i2c_8bit_addr_from_msg(msg);
Kamal Dasudd1aa252015-06-09 15:36:20 -0400447
448 bsc_writel(dev, addr, chip_address);
449 }
450
451 return 0;
452}
453
454/* Master transfer function */
455static int brcmstb_i2c_xfer(struct i2c_adapter *adapter,
456 struct i2c_msg msgs[], int num)
457{
458 struct brcmstb_i2c_dev *dev = i2c_get_adapdata(adapter);
459 struct i2c_msg *pmsg;
460 int rc = 0;
461 int i;
462 int bytes_to_xfer;
463 u8 *tmp_buf;
464 int len = 0;
Kamal Dasue2e5a2c2015-12-16 15:49:09 -0500465 int xfersz = brcmstb_i2c_get_xfersz(dev);
Jaedon Shin2de3ec42017-03-03 10:55:03 +0900466 u32 cond, cond_per_msg;
Kamal Dasudd1aa252015-06-09 15:36:20 -0400467
Kamal Dasudd1aa252015-06-09 15:36:20 -0400468 /* Loop through all messages */
469 for (i = 0; i < num; i++) {
470 pmsg = &msgs[i];
471 len = pmsg->len;
472 tmp_buf = pmsg->buf;
473
474 dev_dbg(dev->device,
475 "msg# %d/%d flg %x buf %x len %d\n", i,
476 num - 1, pmsg->flags,
477 pmsg->buf ? pmsg->buf[0] : '0', pmsg->len);
478
479 if (i < (num - 1) && (msgs[i + 1].flags & I2C_M_NOSTART))
Jaedon Shin2de3ec42017-03-03 10:55:03 +0900480 cond = ~COND_START_STOP;
Kamal Dasudd1aa252015-06-09 15:36:20 -0400481 else
Jaedon Shin2de3ec42017-03-03 10:55:03 +0900482 cond = COND_RESTART | COND_NOSTOP;
483
484 brcmstb_set_i2c_start_stop(dev, cond);
Kamal Dasudd1aa252015-06-09 15:36:20 -0400485
486 /* Send slave address */
487 if (!(pmsg->flags & I2C_M_NOSTART)) {
488 rc = brcmstb_i2c_do_addr(dev, pmsg);
489 if (rc < 0) {
490 dev_dbg(dev->device,
491 "NACK for addr %2.2x msg#%d rc = %d\n",
492 pmsg->addr, i, rc);
493 goto out;
494 }
495 }
496
Jaedon Shin2de3ec42017-03-03 10:55:03 +0900497 cond_per_msg = cond;
498
Kamal Dasudd1aa252015-06-09 15:36:20 -0400499 /* Perform data transfer */
500 while (len) {
Kamal Dasue2e5a2c2015-12-16 15:49:09 -0500501 bytes_to_xfer = min(len, xfersz);
Kamal Dasudd1aa252015-06-09 15:36:20 -0400502
Jaedon Shin2de3ec42017-03-03 10:55:03 +0900503 if (len <= xfersz) {
504 if (i == (num - 1))
505 cond_per_msg = cond_per_msg &
506 ~(COND_RESTART | COND_NOSTOP);
507 else
508 cond_per_msg = cond;
509 } else {
510 cond_per_msg = (cond_per_msg & ~COND_RESTART) |
511 COND_NOSTOP;
512 }
513
514 brcmstb_set_i2c_start_stop(dev, cond_per_msg);
Kamal Dasudd1aa252015-06-09 15:36:20 -0400515
516 rc = brcmstb_i2c_xfer_bsc_data(dev, tmp_buf,
517 bytes_to_xfer, pmsg);
518 if (rc < 0)
519 goto out;
520
521 len -= bytes_to_xfer;
522 tmp_buf += bytes_to_xfer;
Jaedon Shin2de3ec42017-03-03 10:55:03 +0900523
524 cond_per_msg = COND_NOSTART | COND_NOSTOP;
Kamal Dasudd1aa252015-06-09 15:36:20 -0400525 }
526 }
527
528 rc = num;
529out:
530 return rc;
531
532}
533
534static u32 brcmstb_i2c_functionality(struct i2c_adapter *adap)
535{
536 return I2C_FUNC_I2C | I2C_FUNC_SMBUS_EMUL | I2C_FUNC_10BIT_ADDR
537 | I2C_FUNC_NOSTART | I2C_FUNC_PROTOCOL_MANGLING;
538}
539
540static const struct i2c_algorithm brcmstb_i2c_algo = {
541 .master_xfer = brcmstb_i2c_xfer,
542 .functionality = brcmstb_i2c_functionality,
543};
544
545static void brcmstb_i2c_set_bus_speed(struct brcmstb_i2c_dev *dev)
546{
547 int i = 0, num_speeds = ARRAY_SIZE(bsc_clk);
548 u32 clk_freq_hz = dev->clk_freq_hz;
549
550 for (i = 0; i < num_speeds; i++) {
551 if (bsc_clk[i].hz == clk_freq_hz) {
552 dev->bsc_regmap->ctl_reg &= ~(BSC_CTL_REG_SCL_SEL_MASK
553 | BSC_CTL_REG_DIV_CLK_MASK);
554 dev->bsc_regmap->ctl_reg |= (bsc_clk[i].scl_mask |
555 bsc_clk[i].div_mask);
556 bsc_writel(dev, dev->bsc_regmap->ctl_reg, ctl_reg);
557 break;
558 }
559 }
560
561 /* in case we did not get find a valid speed */
562 if (i == num_speeds) {
563 i = (bsc_readl(dev, ctl_reg) & BSC_CTL_REG_SCL_SEL_MASK) >>
564 BSC_CTL_REG_SCL_SEL_SHIFT;
565 dev_warn(dev->device, "leaving current clock-frequency @ %dHz\n",
566 bsc_clk[i].hz);
567 }
568}
569
570static void brcmstb_i2c_set_bsc_reg_defaults(struct brcmstb_i2c_dev *dev)
571{
Kamal Dasue2e5a2c2015-12-16 15:49:09 -0500572 if (brcmstb_i2c_get_data_regsz(dev) == sizeof(u32))
573 /* set 4 byte data in/out xfers */
574 dev->bsc_regmap->ctlhi_reg = BSC_CTLHI_REG_DATAREG_SIZE_MASK;
575 else
576 dev->bsc_regmap->ctlhi_reg &= ~BSC_CTLHI_REG_DATAREG_SIZE_MASK;
577
Kamal Dasudd1aa252015-06-09 15:36:20 -0400578 bsc_writel(dev, dev->bsc_regmap->ctlhi_reg, ctlhi_reg);
579 /* set bus speed */
580 brcmstb_i2c_set_bus_speed(dev);
581}
582
Maxime Ripardd31f59e2020-02-24 10:06:05 +0100583#define AUTOI2C_CTRL0 0x26c
584#define AUTOI2C_CTRL0_RELEASE_BSC BIT(1)
585
586static int bcm2711_release_bsc(struct brcmstb_i2c_dev *dev)
587{
588 struct platform_device *pdev = to_platform_device(dev->device);
589 struct resource *iomem;
590 void __iomem *autoi2c;
591
592 /* Map hardware registers */
593 iomem = platform_get_resource_byname(pdev, IORESOURCE_MEM, "auto-i2c");
594 autoi2c = devm_ioremap_resource(&pdev->dev, iomem);
595 if (IS_ERR(autoi2c))
596 return PTR_ERR(autoi2c);
597
598 writel(AUTOI2C_CTRL0_RELEASE_BSC, autoi2c + AUTOI2C_CTRL0);
599 devm_iounmap(&pdev->dev, autoi2c);
600
601 /* We need to reset the controller after the release */
602 dev->bsc_regmap->iic_enable = 0;
603 bsc_writel(dev, dev->bsc_regmap->iic_enable, iic_enable);
604
605 return 0;
606}
607
Kamal Dasudd1aa252015-06-09 15:36:20 -0400608static int brcmstb_i2c_probe(struct platform_device *pdev)
609{
610 int rc = 0;
611 struct brcmstb_i2c_dev *dev;
612 struct i2c_adapter *adap;
613 struct resource *iomem;
614 const char *int_name;
615
616 /* Allocate memory for private data structure */
617 dev = devm_kzalloc(&pdev->dev, sizeof(*dev), GFP_KERNEL);
618 if (!dev)
619 return -ENOMEM;
620
Wolfram Sang7314d222016-02-21 15:16:48 +0100621 dev->bsc_regmap = devm_kzalloc(&pdev->dev, sizeof(*dev->bsc_regmap), GFP_KERNEL);
Kamal Dasudd1aa252015-06-09 15:36:20 -0400622 if (!dev->bsc_regmap)
623 return -ENOMEM;
624
625 platform_set_drvdata(pdev, dev);
626 dev->device = &pdev->dev;
627 init_completion(&dev->done);
628
629 /* Map hardware registers */
630 iomem = platform_get_resource(pdev, IORESOURCE_MEM, 0);
631 dev->base = devm_ioremap_resource(dev->device, iomem);
632 if (IS_ERR(dev->base)) {
633 rc = -ENOMEM;
634 goto probe_errorout;
635 }
636
Maxime Ripardd31f59e2020-02-24 10:06:05 +0100637 if (of_device_is_compatible(dev->device->of_node,
638 "brcm,bcm2711-hdmi-i2c")) {
639 rc = bcm2711_release_bsc(dev);
640 if (rc)
641 goto probe_errorout;
642 }
643
Kamal Dasudd1aa252015-06-09 15:36:20 -0400644 rc = of_property_read_string(dev->device->of_node, "interrupt-names",
645 &int_name);
646 if (rc < 0)
647 int_name = NULL;
648
649 /* Get the interrupt number */
Dave Stevensonaef6f2e2020-04-25 23:38:07 +0200650 dev->irq = platform_get_irq_optional(pdev, 0);
Kamal Dasudd1aa252015-06-09 15:36:20 -0400651
652 /* disable the bsc interrupt line */
653 brcmstb_i2c_enable_disable_irq(dev, INT_DISABLE);
654
655 /* register the ISR handler */
Dave Stevensonaef6f2e2020-04-25 23:38:07 +0200656 if (dev->irq >= 0) {
657 rc = devm_request_irq(&pdev->dev, dev->irq, brcmstb_i2c_isr,
658 IRQF_SHARED,
659 int_name ? int_name : pdev->name,
660 dev);
Kamal Dasudd1aa252015-06-09 15:36:20 -0400661
Dave Stevensonaef6f2e2020-04-25 23:38:07 +0200662 if (rc) {
663 dev_dbg(dev->device, "falling back to polling mode");
664 dev->irq = -1;
665 }
Kamal Dasudd1aa252015-06-09 15:36:20 -0400666 }
667
668 if (of_property_read_u32(dev->device->of_node,
669 "clock-frequency", &dev->clk_freq_hz)) {
670 dev_warn(dev->device, "setting clock-frequency@%dHz\n",
671 bsc_clk[0].hz);
672 dev->clk_freq_hz = bsc_clk[0].hz;
673 }
674
Kamal Dasue2e5a2c2015-12-16 15:49:09 -0500675 /* set the data in/out register size for compatible SoCs */
676 if (of_device_is_compatible(dev->device->of_node,
677 "brcmstb,brcmper-i2c"))
678 dev->data_regsz = sizeof(u8);
679 else
680 dev->data_regsz = sizeof(u32);
681
Kamal Dasudd1aa252015-06-09 15:36:20 -0400682 brcmstb_i2c_set_bsc_reg_defaults(dev);
683
684 /* Add the i2c adapter */
685 adap = &dev->adapter;
686 i2c_set_adapdata(adap, dev);
687 adap->owner = THIS_MODULE;
688 strlcpy(adap->name, "Broadcom STB : ", sizeof(adap->name));
689 if (int_name)
690 strlcat(adap->name, int_name, sizeof(adap->name));
691 adap->algo = &brcmstb_i2c_algo;
692 adap->dev.parent = &pdev->dev;
693 adap->dev.of_node = pdev->dev.of_node;
694 rc = i2c_add_adapter(adap);
Wolfram Sangea734402016-08-09 13:36:17 +0200695 if (rc)
Kamal Dasudd1aa252015-06-09 15:36:20 -0400696 goto probe_errorout;
Kamal Dasudd1aa252015-06-09 15:36:20 -0400697
698 dev_info(dev->device, "%s@%dhz registered in %s mode\n",
699 int_name ? int_name : " ", dev->clk_freq_hz,
700 (dev->irq >= 0) ? "interrupt" : "polling");
701
702 return 0;
703
704probe_errorout:
705 return rc;
706}
707
708static int brcmstb_i2c_remove(struct platform_device *pdev)
709{
710 struct brcmstb_i2c_dev *dev = platform_get_drvdata(pdev);
711
712 i2c_del_adapter(&dev->adapter);
713 return 0;
714}
715
716#ifdef CONFIG_PM_SLEEP
717static int brcmstb_i2c_suspend(struct device *dev)
718{
719 struct brcmstb_i2c_dev *i2c_dev = dev_get_drvdata(dev);
720
Wolfram Sangf2e0d282018-12-19 17:48:20 +0100721 i2c_mark_adapter_suspended(&i2c_dev->adapter);
Kamal Dasudd1aa252015-06-09 15:36:20 -0400722 return 0;
723}
724
725static int brcmstb_i2c_resume(struct device *dev)
726{
727 struct brcmstb_i2c_dev *i2c_dev = dev_get_drvdata(dev);
728
Kamal Dasudd1aa252015-06-09 15:36:20 -0400729 brcmstb_i2c_set_bsc_reg_defaults(i2c_dev);
Wolfram Sangf2e0d282018-12-19 17:48:20 +0100730 i2c_mark_adapter_resumed(&i2c_dev->adapter);
Kamal Dasudd1aa252015-06-09 15:36:20 -0400731
732 return 0;
733}
734#endif
735
736static SIMPLE_DEV_PM_OPS(brcmstb_i2c_pm, brcmstb_i2c_suspend,
737 brcmstb_i2c_resume);
738
739static const struct of_device_id brcmstb_i2c_of_match[] = {
740 {.compatible = "brcm,brcmstb-i2c"},
Kamal Dasue2e5a2c2015-12-16 15:49:09 -0500741 {.compatible = "brcm,brcmper-i2c"},
Maxime Ripardd31f59e2020-02-24 10:06:05 +0100742 {.compatible = "brcm,bcm2711-hdmi-i2c"},
Kamal Dasudd1aa252015-06-09 15:36:20 -0400743 {},
744};
745MODULE_DEVICE_TABLE(of, brcmstb_i2c_of_match);
746
747static struct platform_driver brcmstb_i2c_driver = {
748 .driver = {
749 .name = "brcmstb-i2c",
750 .of_match_table = brcmstb_i2c_of_match,
751 .pm = &brcmstb_i2c_pm,
752 },
753 .probe = brcmstb_i2c_probe,
754 .remove = brcmstb_i2c_remove,
755};
756module_platform_driver(brcmstb_i2c_driver);
757
758MODULE_AUTHOR("Kamal Dasu <kdasu@broadcom.com>");
759MODULE_DESCRIPTION("Broadcom Settop I2C Driver");
760MODULE_LICENSE("GPL v2");