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Komal Shah010d442c42006-08-13 23:44:09 +02001/*
2 * TI OMAP I2C master mode driver
3 *
4 * Copyright (C) 2003 MontaVista Software, Inc.
Komal Shah010d442c42006-08-13 23:44:09 +02005 * Copyright (C) 2005 Nokia Corporation
Tony Lindgrenc1a473b2008-11-21 13:39:47 -08006 * Copyright (C) 2004 - 2007 Texas Instruments.
Komal Shah010d442c42006-08-13 23:44:09 +02007 *
Tony Lindgrenc1a473b2008-11-21 13:39:47 -08008 * Originally written by MontaVista Software, Inc.
9 * Additional contributions by:
10 * Tony Lindgren <tony@atomide.com>
11 * Imre Deak <imre.deak@nokia.com>
12 * Juha Yrjölä <juha.yrjola@solidboot.com>
13 * Syed Khasim <x0khasim@ti.com>
14 * Nishant Menon <nm@ti.com>
Komal Shah010d442c42006-08-13 23:44:09 +020015 *
16 * This program is free software; you can redistribute it and/or modify
17 * it under the terms of the GNU General Public License as published by
18 * the Free Software Foundation; either version 2 of the License, or
19 * (at your option) any later version.
20 *
21 * This program is distributed in the hope that it will be useful,
22 * but WITHOUT ANY WARRANTY; without even the implied warranty of
23 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
24 * GNU General Public License for more details.
25 *
26 * You should have received a copy of the GNU General Public License
27 * along with this program; if not, write to the Free Software
28 * Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
29 */
30
31#include <linux/module.h>
32#include <linux/delay.h>
33#include <linux/i2c.h>
34#include <linux/err.h>
35#include <linux/interrupt.h>
36#include <linux/completion.h>
37#include <linux/platform_device.h>
38#include <linux/clk.h>
Tony Lindgrenc1a473b2008-11-21 13:39:47 -080039#include <linux/io.h>
Tejun Heo5a0e3ad2010-03-24 17:04:11 +090040#include <linux/slab.h>
Kalle Jokiniemi20c9d2c2010-05-11 11:35:08 -070041#include <linux/i2c-omap.h>
Komal Shah010d442c42006-08-13 23:44:09 +020042
Paul Walmsley9c76b872008-11-21 13:39:55 -080043/* I2C controller revisions */
44#define OMAP_I2C_REV_2 0x20
45
46/* I2C controller revisions present on specific hardware */
47#define OMAP_I2C_REV_ON_2430 0x36
48#define OMAP_I2C_REV_ON_3430 0x3C
Santosh Shilimkarf38e66e2010-05-11 11:35:04 -070049#define OMAP_I2C_REV_ON_4430 0x40
Paul Walmsley9c76b872008-11-21 13:39:55 -080050
Komal Shah010d442c42006-08-13 23:44:09 +020051/* timeout waiting for the controller to respond */
52#define OMAP_I2C_TIMEOUT (msecs_to_jiffies(1000))
53
Kalle Jokiniemi5043e9e72008-11-21 13:39:55 -080054/* For OMAP3 I2C_IV has changed to I2C_WE (wakeup enable) */
Santosh Shilimkarf38e66e2010-05-11 11:35:04 -070055enum {
56 OMAP_I2C_REV_REG = 0,
57 OMAP_I2C_IE_REG,
58 OMAP_I2C_STAT_REG,
59 OMAP_I2C_IV_REG,
60 OMAP_I2C_WE_REG,
61 OMAP_I2C_SYSS_REG,
62 OMAP_I2C_BUF_REG,
63 OMAP_I2C_CNT_REG,
64 OMAP_I2C_DATA_REG,
65 OMAP_I2C_SYSC_REG,
66 OMAP_I2C_CON_REG,
67 OMAP_I2C_OA_REG,
68 OMAP_I2C_SA_REG,
69 OMAP_I2C_PSC_REG,
70 OMAP_I2C_SCLL_REG,
71 OMAP_I2C_SCLH_REG,
72 OMAP_I2C_SYSTEST_REG,
73 OMAP_I2C_BUFSTAT_REG,
74 OMAP_I2C_REVNB_LO,
75 OMAP_I2C_REVNB_HI,
76 OMAP_I2C_IRQSTATUS_RAW,
77 OMAP_I2C_IRQENABLE_SET,
78 OMAP_I2C_IRQENABLE_CLR,
79};
Komal Shah010d442c42006-08-13 23:44:09 +020080
81/* I2C Interrupt Enable Register (OMAP_I2C_IE): */
Nishanth Menonb6ee52c2008-11-21 13:39:46 -080082#define OMAP_I2C_IE_XDR (1 << 14) /* TX Buffer drain int enable */
83#define OMAP_I2C_IE_RDR (1 << 13) /* RX Buffer drain int enable */
Komal Shah010d442c42006-08-13 23:44:09 +020084#define OMAP_I2C_IE_XRDY (1 << 4) /* TX data ready int enable */
85#define OMAP_I2C_IE_RRDY (1 << 3) /* RX data ready int enable */
86#define OMAP_I2C_IE_ARDY (1 << 2) /* Access ready int enable */
87#define OMAP_I2C_IE_NACK (1 << 1) /* No ack interrupt enable */
88#define OMAP_I2C_IE_AL (1 << 0) /* Arbitration lost int ena */
89
90/* I2C Status Register (OMAP_I2C_STAT): */
Nishanth Menonb6ee52c2008-11-21 13:39:46 -080091#define OMAP_I2C_STAT_XDR (1 << 14) /* TX Buffer draining */
92#define OMAP_I2C_STAT_RDR (1 << 13) /* RX Buffer draining */
Komal Shah010d442c42006-08-13 23:44:09 +020093#define OMAP_I2C_STAT_BB (1 << 12) /* Bus busy */
94#define OMAP_I2C_STAT_ROVR (1 << 11) /* Receive overrun */
95#define OMAP_I2C_STAT_XUDF (1 << 10) /* Transmit underflow */
96#define OMAP_I2C_STAT_AAS (1 << 9) /* Address as slave */
97#define OMAP_I2C_STAT_AD0 (1 << 8) /* Address zero */
98#define OMAP_I2C_STAT_XRDY (1 << 4) /* Transmit data ready */
99#define OMAP_I2C_STAT_RRDY (1 << 3) /* Receive data ready */
100#define OMAP_I2C_STAT_ARDY (1 << 2) /* Register access ready */
101#define OMAP_I2C_STAT_NACK (1 << 1) /* No ack interrupt enable */
102#define OMAP_I2C_STAT_AL (1 << 0) /* Arbitration lost int ena */
103
Kalle Jokiniemi5043e9e72008-11-21 13:39:55 -0800104/* I2C WE wakeup enable register */
105#define OMAP_I2C_WE_XDR_WE (1 << 14) /* TX drain wakup */
106#define OMAP_I2C_WE_RDR_WE (1 << 13) /* RX drain wakeup */
107#define OMAP_I2C_WE_AAS_WE (1 << 9) /* Address as slave wakeup*/
108#define OMAP_I2C_WE_BF_WE (1 << 8) /* Bus free wakeup */
109#define OMAP_I2C_WE_STC_WE (1 << 6) /* Start condition wakeup */
110#define OMAP_I2C_WE_GC_WE (1 << 5) /* General call wakeup */
111#define OMAP_I2C_WE_DRDY_WE (1 << 3) /* TX/RX data ready wakeup */
112#define OMAP_I2C_WE_ARDY_WE (1 << 2) /* Reg access ready wakeup */
113#define OMAP_I2C_WE_NACK_WE (1 << 1) /* No acknowledgment wakeup */
114#define OMAP_I2C_WE_AL_WE (1 << 0) /* Arbitration lost wakeup */
115
116#define OMAP_I2C_WE_ALL (OMAP_I2C_WE_XDR_WE | OMAP_I2C_WE_RDR_WE | \
117 OMAP_I2C_WE_AAS_WE | OMAP_I2C_WE_BF_WE | \
118 OMAP_I2C_WE_STC_WE | OMAP_I2C_WE_GC_WE | \
119 OMAP_I2C_WE_DRDY_WE | OMAP_I2C_WE_ARDY_WE | \
120 OMAP_I2C_WE_NACK_WE | OMAP_I2C_WE_AL_WE)
121
Komal Shah010d442c42006-08-13 23:44:09 +0200122/* I2C Buffer Configuration Register (OMAP_I2C_BUF): */
123#define OMAP_I2C_BUF_RDMA_EN (1 << 15) /* RX DMA channel enable */
Nishanth Menonb6ee52c2008-11-21 13:39:46 -0800124#define OMAP_I2C_BUF_RXFIF_CLR (1 << 14) /* RX FIFO Clear */
Komal Shah010d442c42006-08-13 23:44:09 +0200125#define OMAP_I2C_BUF_XDMA_EN (1 << 7) /* TX DMA channel enable */
Nishanth Menonb6ee52c2008-11-21 13:39:46 -0800126#define OMAP_I2C_BUF_TXFIF_CLR (1 << 6) /* TX FIFO Clear */
Komal Shah010d442c42006-08-13 23:44:09 +0200127
128/* I2C Configuration Register (OMAP_I2C_CON): */
129#define OMAP_I2C_CON_EN (1 << 15) /* I2C module enable */
130#define OMAP_I2C_CON_BE (1 << 14) /* Big endian mode */
Nishanth Menonb6ee52c2008-11-21 13:39:46 -0800131#define OMAP_I2C_CON_OPMODE_HS (1 << 12) /* High Speed support */
Komal Shah010d442c42006-08-13 23:44:09 +0200132#define OMAP_I2C_CON_STB (1 << 11) /* Start byte mode (master) */
133#define OMAP_I2C_CON_MST (1 << 10) /* Master/slave mode */
134#define OMAP_I2C_CON_TRX (1 << 9) /* TX/RX mode (master only) */
135#define OMAP_I2C_CON_XA (1 << 8) /* Expand address */
136#define OMAP_I2C_CON_RM (1 << 2) /* Repeat mode (master only) */
137#define OMAP_I2C_CON_STP (1 << 1) /* Stop cond (master only) */
138#define OMAP_I2C_CON_STT (1 << 0) /* Start condition (master) */
139
Syed Mohammed Khasim4574eb62008-11-21 13:39:45 -0800140/* I2C SCL time value when Master */
141#define OMAP_I2C_SCLL_HSSCLL 8
142#define OMAP_I2C_SCLH_HSSCLH 8
143
Komal Shah010d442c42006-08-13 23:44:09 +0200144/* I2C System Test Register (OMAP_I2C_SYSTEST): */
145#ifdef DEBUG
146#define OMAP_I2C_SYSTEST_ST_EN (1 << 15) /* System test enable */
147#define OMAP_I2C_SYSTEST_FREE (1 << 14) /* Free running mode */
148#define OMAP_I2C_SYSTEST_TMODE_MASK (3 << 12) /* Test mode select */
149#define OMAP_I2C_SYSTEST_TMODE_SHIFT (12) /* Test mode select */
150#define OMAP_I2C_SYSTEST_SCL_I (1 << 3) /* SCL line sense in */
151#define OMAP_I2C_SYSTEST_SCL_O (1 << 2) /* SCL line drive out */
152#define OMAP_I2C_SYSTEST_SDA_I (1 << 1) /* SDA line sense in */
153#define OMAP_I2C_SYSTEST_SDA_O (1 << 0) /* SDA line drive out */
154#endif
155
Paul Walmsleyfdd07fe2008-11-21 13:39:55 -0800156/* OCP_SYSSTATUS bit definitions */
157#define SYSS_RESETDONE_MASK (1 << 0)
Komal Shah010d442c42006-08-13 23:44:09 +0200158
Paul Walmsleyfdd07fe2008-11-21 13:39:55 -0800159/* OCP_SYSCONFIG bit definitions */
160#define SYSC_CLOCKACTIVITY_MASK (0x3 << 8)
161#define SYSC_SIDLEMODE_MASK (0x3 << 3)
162#define SYSC_ENAWAKEUP_MASK (1 << 2)
163#define SYSC_SOFTRESET_MASK (1 << 1)
164#define SYSC_AUTOIDLE_MASK (1 << 0)
165
166#define SYSC_IDLEMODE_SMART 0x2
167#define SYSC_CLOCKACTIVITY_FCLK 0x2
168
manjugk manjugkf3083d92010-05-11 11:35:20 -0700169/* Errata definitions */
170#define I2C_OMAP_ERRATA_I207 (1 << 0)
Komal Shah010d442c42006-08-13 23:44:09 +0200171
Komal Shah010d442c42006-08-13 23:44:09 +0200172struct omap_i2c_dev {
173 struct device *dev;
174 void __iomem *base; /* virtual */
175 int irq;
Cory Maccarroned84d3ea2009-12-12 17:54:02 -0800176 int reg_shift; /* bit shift for I2C register addresses */
Komal Shah010d442c42006-08-13 23:44:09 +0200177 struct clk *iclk; /* Interface clock */
178 struct clk *fclk; /* Functional clock */
179 struct completion cmd_complete;
180 struct resource *ioarea;
Kalle Jokiniemi20c9d2c2010-05-11 11:35:08 -0700181 u32 latency; /* maximum mpu wkup latency */
182 void (*set_mpu_wkup_lat)(struct device *dev,
183 long latency);
Syed Mohammed Khasim4574eb62008-11-21 13:39:45 -0800184 u32 speed; /* Speed of bus in Khz */
Komal Shah010d442c42006-08-13 23:44:09 +0200185 u16 cmd_err;
186 u8 *buf;
Santosh Shilimkarf38e66e2010-05-11 11:35:04 -0700187 u8 *regs;
Komal Shah010d442c42006-08-13 23:44:09 +0200188 size_t buf_len;
189 struct i2c_adapter adapter;
Nishanth Menonb6ee52c2008-11-21 13:39:46 -0800190 u8 fifo_size; /* use as flag and value
191 * fifo_size==0 implies no fifo
192 * if set, should be trsh+1
193 */
Paul Walmsley9c76b872008-11-21 13:39:55 -0800194 u8 rev;
Nishanth Menonb6ee52c2008-11-21 13:39:46 -0800195 unsigned b_hw:1; /* bad h/w fixes */
Tony Lindgrenf08ac4e2008-03-23 20:28:20 +0100196 unsigned idle:1;
197 u16 iestate; /* Saved interrupt register */
Rajendra Nayakef871432009-11-23 08:59:18 -0800198 u16 pscstate;
199 u16 scllstate;
200 u16 sclhstate;
201 u16 bufstate;
202 u16 syscstate;
203 u16 westate;
manjugk manjugkf3083d92010-05-11 11:35:20 -0700204 u16 errata;
Komal Shah010d442c42006-08-13 23:44:09 +0200205};
206
Santosh Shilimkarf38e66e2010-05-11 11:35:04 -0700207const static u8 reg_map[] = {
208 [OMAP_I2C_REV_REG] = 0x00,
209 [OMAP_I2C_IE_REG] = 0x01,
210 [OMAP_I2C_STAT_REG] = 0x02,
211 [OMAP_I2C_IV_REG] = 0x03,
212 [OMAP_I2C_WE_REG] = 0x03,
213 [OMAP_I2C_SYSS_REG] = 0x04,
214 [OMAP_I2C_BUF_REG] = 0x05,
215 [OMAP_I2C_CNT_REG] = 0x06,
216 [OMAP_I2C_DATA_REG] = 0x07,
217 [OMAP_I2C_SYSC_REG] = 0x08,
218 [OMAP_I2C_CON_REG] = 0x09,
219 [OMAP_I2C_OA_REG] = 0x0a,
220 [OMAP_I2C_SA_REG] = 0x0b,
221 [OMAP_I2C_PSC_REG] = 0x0c,
222 [OMAP_I2C_SCLL_REG] = 0x0d,
223 [OMAP_I2C_SCLH_REG] = 0x0e,
224 [OMAP_I2C_SYSTEST_REG] = 0x0f,
225 [OMAP_I2C_BUFSTAT_REG] = 0x10,
226};
227
228const static u8 omap4_reg_map[] = {
229 [OMAP_I2C_REV_REG] = 0x04,
230 [OMAP_I2C_IE_REG] = 0x2c,
231 [OMAP_I2C_STAT_REG] = 0x28,
232 [OMAP_I2C_IV_REG] = 0x34,
233 [OMAP_I2C_WE_REG] = 0x34,
234 [OMAP_I2C_SYSS_REG] = 0x90,
235 [OMAP_I2C_BUF_REG] = 0x94,
236 [OMAP_I2C_CNT_REG] = 0x98,
237 [OMAP_I2C_DATA_REG] = 0x9c,
238 [OMAP_I2C_SYSC_REG] = 0x20,
239 [OMAP_I2C_CON_REG] = 0xa4,
240 [OMAP_I2C_OA_REG] = 0xa8,
241 [OMAP_I2C_SA_REG] = 0xac,
242 [OMAP_I2C_PSC_REG] = 0xb0,
243 [OMAP_I2C_SCLL_REG] = 0xb4,
244 [OMAP_I2C_SCLH_REG] = 0xb8,
245 [OMAP_I2C_SYSTEST_REG] = 0xbC,
246 [OMAP_I2C_BUFSTAT_REG] = 0xc0,
247 [OMAP_I2C_REVNB_LO] = 0x00,
248 [OMAP_I2C_REVNB_HI] = 0x04,
249 [OMAP_I2C_IRQSTATUS_RAW] = 0x24,
250 [OMAP_I2C_IRQENABLE_SET] = 0x2c,
251 [OMAP_I2C_IRQENABLE_CLR] = 0x30,
252};
253
Komal Shah010d442c42006-08-13 23:44:09 +0200254static inline void omap_i2c_write_reg(struct omap_i2c_dev *i2c_dev,
255 int reg, u16 val)
256{
Santosh Shilimkarf38e66e2010-05-11 11:35:04 -0700257 __raw_writew(val, i2c_dev->base +
258 (i2c_dev->regs[reg] << i2c_dev->reg_shift));
Komal Shah010d442c42006-08-13 23:44:09 +0200259}
260
261static inline u16 omap_i2c_read_reg(struct omap_i2c_dev *i2c_dev, int reg)
262{
Santosh Shilimkarf38e66e2010-05-11 11:35:04 -0700263 return __raw_readw(i2c_dev->base +
264 (i2c_dev->regs[reg] << i2c_dev->reg_shift));
Komal Shah010d442c42006-08-13 23:44:09 +0200265}
266
Paul Walmsley510be9c2008-11-21 13:39:46 -0800267static int __init omap_i2c_get_clocks(struct omap_i2c_dev *dev)
Komal Shah010d442c42006-08-13 23:44:09 +0200268{
Russell King5fe23382009-01-23 22:57:12 +0000269 int ret;
270
271 dev->iclk = clk_get(dev->dev, "ick");
272 if (IS_ERR(dev->iclk)) {
273 ret = PTR_ERR(dev->iclk);
274 dev->iclk = NULL;
275 return ret;
Komal Shah010d442c42006-08-13 23:44:09 +0200276 }
277
Russell King1d14de02009-01-19 21:02:29 +0000278 dev->fclk = clk_get(dev->dev, "fck");
Komal Shah010d442c42006-08-13 23:44:09 +0200279 if (IS_ERR(dev->fclk)) {
Russell King5fe23382009-01-23 22:57:12 +0000280 ret = PTR_ERR(dev->fclk);
Komal Shah010d442c42006-08-13 23:44:09 +0200281 if (dev->iclk != NULL) {
282 clk_put(dev->iclk);
283 dev->iclk = NULL;
284 }
285 dev->fclk = NULL;
Russell King5fe23382009-01-23 22:57:12 +0000286 return ret;
Komal Shah010d442c42006-08-13 23:44:09 +0200287 }
288
289 return 0;
290}
291
292static void omap_i2c_put_clocks(struct omap_i2c_dev *dev)
293{
294 clk_put(dev->fclk);
295 dev->fclk = NULL;
Russell King5fe23382009-01-23 22:57:12 +0000296 clk_put(dev->iclk);
297 dev->iclk = NULL;
Komal Shah010d442c42006-08-13 23:44:09 +0200298}
299
Tony Lindgrenf08ac4e2008-03-23 20:28:20 +0100300static void omap_i2c_unidle(struct omap_i2c_dev *dev)
Komal Shah010d442c42006-08-13 23:44:09 +0200301{
Paul Walmsley3831f152008-11-21 13:39:47 -0800302 WARN_ON(!dev->idle);
303
Russell King5fe23382009-01-23 22:57:12 +0000304 clk_enable(dev->iclk);
Komal Shah010d442c42006-08-13 23:44:09 +0200305 clk_enable(dev->fclk);
Rajendra Nayakef871432009-11-23 08:59:18 -0800306 if (cpu_is_omap34xx()) {
307 omap_i2c_write_reg(dev, OMAP_I2C_CON_REG, 0);
308 omap_i2c_write_reg(dev, OMAP_I2C_PSC_REG, dev->pscstate);
309 omap_i2c_write_reg(dev, OMAP_I2C_SCLL_REG, dev->scllstate);
310 omap_i2c_write_reg(dev, OMAP_I2C_SCLH_REG, dev->sclhstate);
311 omap_i2c_write_reg(dev, OMAP_I2C_BUF_REG, dev->bufstate);
312 omap_i2c_write_reg(dev, OMAP_I2C_SYSC_REG, dev->syscstate);
313 omap_i2c_write_reg(dev, OMAP_I2C_WE_REG, dev->westate);
314 omap_i2c_write_reg(dev, OMAP_I2C_CON_REG, OMAP_I2C_CON_EN);
315 }
Paul Walmsley0cbbcff2008-11-21 13:39:45 -0800316 dev->idle = 0;
Cory Maccarrone07ac31f2009-12-22 18:06:13 -0700317
318 /*
319 * Don't write to this register if the IE state is 0 as it can
320 * cause deadlock.
321 */
322 if (dev->iestate)
323 omap_i2c_write_reg(dev, OMAP_I2C_IE_REG, dev->iestate);
Komal Shah010d442c42006-08-13 23:44:09 +0200324}
325
Tony Lindgrenf08ac4e2008-03-23 20:28:20 +0100326static void omap_i2c_idle(struct omap_i2c_dev *dev)
Komal Shah010d442c42006-08-13 23:44:09 +0200327{
Tony Lindgrenf08ac4e2008-03-23 20:28:20 +0100328 u16 iv;
329
Paul Walmsley3831f152008-11-21 13:39:47 -0800330 WARN_ON(dev->idle);
331
Tony Lindgrenf08ac4e2008-03-23 20:28:20 +0100332 dev->iestate = omap_i2c_read_reg(dev, OMAP_I2C_IE_REG);
Santosh Shilimkarf38e66e2010-05-11 11:35:04 -0700333 if (dev->rev >= OMAP_I2C_REV_ON_4430)
334 omap_i2c_write_reg(dev, OMAP_I2C_IRQENABLE_CLR, 1);
335 else
336 omap_i2c_write_reg(dev, OMAP_I2C_IE_REG, 0);
337
Paul Walmsley9c76b872008-11-21 13:39:55 -0800338 if (dev->rev < OMAP_I2C_REV_2) {
Tony Lindgrenc1a473b2008-11-21 13:39:47 -0800339 iv = omap_i2c_read_reg(dev, OMAP_I2C_IV_REG); /* Read clears */
Paul Walmsley0cbbcff2008-11-21 13:39:45 -0800340 } else {
Tony Lindgrenf08ac4e2008-03-23 20:28:20 +0100341 omap_i2c_write_reg(dev, OMAP_I2C_STAT_REG, dev->iestate);
Paul Walmsley0cbbcff2008-11-21 13:39:45 -0800342
343 /* Flush posted write before the dev->idle store occurs */
344 omap_i2c_read_reg(dev, OMAP_I2C_STAT_REG);
345 }
346 dev->idle = 1;
Tony Lindgrenf08ac4e2008-03-23 20:28:20 +0100347 clk_disable(dev->fclk);
Russell King5fe23382009-01-23 22:57:12 +0000348 clk_disable(dev->iclk);
Komal Shah010d442c42006-08-13 23:44:09 +0200349}
350
351static int omap_i2c_init(struct omap_i2c_dev *dev)
352{
Rajendra Nayakef871432009-11-23 08:59:18 -0800353 u16 psc = 0, scll = 0, sclh = 0, buf = 0;
Syed Mohammed Khasim4574eb62008-11-21 13:39:45 -0800354 u16 fsscll = 0, fssclh = 0, hsscll = 0, hssclh = 0;
Komal Shah010d442c42006-08-13 23:44:09 +0200355 unsigned long fclk_rate = 12000000;
356 unsigned long timeout;
Syed Mohammed Khasim4574eb62008-11-21 13:39:45 -0800357 unsigned long internal_clk = 0;
Komal Shah010d442c42006-08-13 23:44:09 +0200358
Paul Walmsley9c76b872008-11-21 13:39:55 -0800359 if (dev->rev >= OMAP_I2C_REV_2) {
Manjunatha GK57eb81b2009-12-11 11:09:08 +0530360 /* Disable I2C controller before soft reset */
361 omap_i2c_write_reg(dev, OMAP_I2C_CON_REG,
362 omap_i2c_read_reg(dev, OMAP_I2C_CON_REG) &
363 ~(OMAP_I2C_CON_EN));
364
Paul Walmsleyfdd07fe2008-11-21 13:39:55 -0800365 omap_i2c_write_reg(dev, OMAP_I2C_SYSC_REG, SYSC_SOFTRESET_MASK);
Komal Shah010d442c42006-08-13 23:44:09 +0200366 /* For some reason we need to set the EN bit before the
367 * reset done bit gets set. */
368 timeout = jiffies + OMAP_I2C_TIMEOUT;
369 omap_i2c_write_reg(dev, OMAP_I2C_CON_REG, OMAP_I2C_CON_EN);
370 while (!(omap_i2c_read_reg(dev, OMAP_I2C_SYSS_REG) &
Paul Walmsleyfdd07fe2008-11-21 13:39:55 -0800371 SYSS_RESETDONE_MASK)) {
Komal Shah010d442c42006-08-13 23:44:09 +0200372 if (time_after(jiffies, timeout)) {
Joe Perchesfce3ff02007-12-12 13:45:24 +0100373 dev_warn(dev->dev, "timeout waiting "
Komal Shah010d442c42006-08-13 23:44:09 +0200374 "for controller reset\n");
375 return -ETIMEDOUT;
376 }
377 msleep(1);
378 }
Paul Walmsleyfdd07fe2008-11-21 13:39:55 -0800379
380 /* SYSC register is cleared by the reset; rewrite it */
381 if (dev->rev == OMAP_I2C_REV_ON_2430) {
382
383 omap_i2c_write_reg(dev, OMAP_I2C_SYSC_REG,
384 SYSC_AUTOIDLE_MASK);
385
386 } else if (dev->rev >= OMAP_I2C_REV_ON_3430) {
Rajendra Nayakef871432009-11-23 08:59:18 -0800387 dev->syscstate = SYSC_AUTOIDLE_MASK;
388 dev->syscstate |= SYSC_ENAWAKEUP_MASK;
389 dev->syscstate |= (SYSC_IDLEMODE_SMART <<
Paul Walmsleyfdd07fe2008-11-21 13:39:55 -0800390 __ffs(SYSC_SIDLEMODE_MASK));
Rajendra Nayakef871432009-11-23 08:59:18 -0800391 dev->syscstate |= (SYSC_CLOCKACTIVITY_FCLK <<
Paul Walmsleyfdd07fe2008-11-21 13:39:55 -0800392 __ffs(SYSC_CLOCKACTIVITY_MASK));
393
Rajendra Nayakef871432009-11-23 08:59:18 -0800394 omap_i2c_write_reg(dev, OMAP_I2C_SYSC_REG,
395 dev->syscstate);
Kalle Jokiniemi5043e9e72008-11-21 13:39:55 -0800396 /*
397 * Enabling all wakup sources to stop I2C freezing on
398 * WFI instruction.
399 * REVISIT: Some wkup sources might not be needed.
400 */
Rajendra Nayakef871432009-11-23 08:59:18 -0800401 dev->westate = OMAP_I2C_WE_ALL;
Santosh Shilimkarf38e66e2010-05-11 11:35:04 -0700402 if (dev->rev < OMAP_I2C_REV_ON_4430)
403 omap_i2c_write_reg(dev, OMAP_I2C_WE_REG,
404 dev->westate);
Paul Walmsleyfdd07fe2008-11-21 13:39:55 -0800405 }
Komal Shah010d442c42006-08-13 23:44:09 +0200406 }
407 omap_i2c_write_reg(dev, OMAP_I2C_CON_REG, 0);
408
409 if (cpu_class_is_omap1()) {
Russell King0e9ae102009-01-22 19:31:46 +0000410 /*
411 * The I2C functional clock is the armxor_ck, so there's
412 * no need to get "armxor_ck" separately. Now, if OMAP2420
413 * always returns 12MHz for the functional clock, we can
414 * do this bit unconditionally.
415 */
416 fclk_rate = clk_get_rate(dev->fclk);
Komal Shah010d442c42006-08-13 23:44:09 +0200417
Komal Shah010d442c42006-08-13 23:44:09 +0200418 /* TRM for 5912 says the I2C clock must be prescaled to be
419 * between 7 - 12 MHz. The XOR input clock is typically
420 * 12, 13 or 19.2 MHz. So we should have code that produces:
421 *
422 * XOR MHz Divider Prescaler
423 * 12 1 0
424 * 13 2 1
425 * 19.2 2 1
426 */
Jean Delvared7aef132006-12-10 21:21:34 +0100427 if (fclk_rate > 12000000)
428 psc = fclk_rate / 12000000;
Komal Shah010d442c42006-08-13 23:44:09 +0200429 }
430
Santosh Shilimkarf38e66e2010-05-11 11:35:04 -0700431 if (!(cpu_class_is_omap1() || cpu_is_omap2420())) {
Syed Mohammed Khasim4574eb62008-11-21 13:39:45 -0800432
Aaro Koskinen84bf2c82009-05-27 17:54:46 +0300433 /*
434 * HSI2C controller internal clk rate should be 19.2 Mhz for
435 * HS and for all modes on 2430. On 34xx we can use lower rate
436 * to get longer filter period for better noise suppression.
437 * The filter is iclk (fclk for HS) period.
438 */
Tony Lindgrenff0f2422009-06-17 03:20:21 -0700439 if (dev->speed > 400 || cpu_is_omap2430())
Aaro Koskinen84bf2c82009-05-27 17:54:46 +0300440 internal_clk = 19200;
441 else if (dev->speed > 100)
442 internal_clk = 9600;
443 else
444 internal_clk = 4000;
Syed Mohammed Khasim4574eb62008-11-21 13:39:45 -0800445 fclk_rate = clk_get_rate(dev->fclk) / 1000;
446
447 /* Compute prescaler divisor */
448 psc = fclk_rate / internal_clk;
449 psc = psc - 1;
450
451 /* If configured for High Speed */
452 if (dev->speed > 400) {
Aaro Koskinenbaf46b42009-05-27 17:54:45 +0300453 unsigned long scl;
454
Syed Mohammed Khasim4574eb62008-11-21 13:39:45 -0800455 /* For first phase of HS mode */
Aaro Koskinenbaf46b42009-05-27 17:54:45 +0300456 scl = internal_clk / 400;
457 fsscll = scl - (scl / 3) - 7;
458 fssclh = (scl / 3) - 5;
Syed Mohammed Khasim4574eb62008-11-21 13:39:45 -0800459
460 /* For second phase of HS mode */
Aaro Koskinenbaf46b42009-05-27 17:54:45 +0300461 scl = fclk_rate / dev->speed;
462 hsscll = scl - (scl / 3) - 7;
463 hssclh = (scl / 3) - 5;
464 } else if (dev->speed > 100) {
465 unsigned long scl;
466
467 /* Fast mode */
468 scl = internal_clk / dev->speed;
469 fsscll = scl - (scl / 3) - 7;
470 fssclh = (scl / 3) - 5;
Syed Mohammed Khasim4574eb62008-11-21 13:39:45 -0800471 } else {
Aaro Koskinenbaf46b42009-05-27 17:54:45 +0300472 /* Standard mode */
473 fsscll = internal_clk / (dev->speed * 2) - 7;
474 fssclh = internal_clk / (dev->speed * 2) - 5;
Syed Mohammed Khasim4574eb62008-11-21 13:39:45 -0800475 }
476 scll = (hsscll << OMAP_I2C_SCLL_HSSCLL) | fsscll;
477 sclh = (hssclh << OMAP_I2C_SCLH_HSSCLH) | fssclh;
478 } else {
479 /* Program desired operating rate */
480 fclk_rate /= (psc + 1) * 1000;
481 if (psc > 2)
482 psc = 2;
483 scll = fclk_rate / (dev->speed * 2) - 7 + psc;
484 sclh = fclk_rate / (dev->speed * 2) - 7 + psc;
485 }
486
Komal Shah010d442c42006-08-13 23:44:09 +0200487 /* Setup clock prescaler to obtain approx 12MHz I2C module clock: */
488 omap_i2c_write_reg(dev, OMAP_I2C_PSC_REG, psc);
489
Syed Mohammed Khasim4574eb62008-11-21 13:39:45 -0800490 /* SCL low and high time values */
491 omap_i2c_write_reg(dev, OMAP_I2C_SCLL_REG, scll);
492 omap_i2c_write_reg(dev, OMAP_I2C_SCLH_REG, sclh);
Komal Shah010d442c42006-08-13 23:44:09 +0200493
Rajendra Nayakef871432009-11-23 08:59:18 -0800494 if (dev->fifo_size) {
495 /* Note: setup required fifo size - 1. RTRSH and XTRSH */
496 buf = (dev->fifo_size - 1) << 8 | OMAP_I2C_BUF_RXFIF_CLR |
497 (dev->fifo_size - 1) | OMAP_I2C_BUF_TXFIF_CLR;
498 omap_i2c_write_reg(dev, OMAP_I2C_BUF_REG, buf);
499 }
Nishanth Menonb6ee52c2008-11-21 13:39:46 -0800500
Komal Shah010d442c42006-08-13 23:44:09 +0200501 /* Take the I2C module out of reset: */
502 omap_i2c_write_reg(dev, OMAP_I2C_CON_REG, OMAP_I2C_CON_EN);
503
manjugk manjugkf3083d92010-05-11 11:35:20 -0700504 dev->errata = 0;
505
506 if (cpu_is_omap2430() || cpu_is_omap34xx())
507 dev->errata |= I2C_OMAP_ERRATA_I207;
508
Komal Shah010d442c42006-08-13 23:44:09 +0200509 /* Enable interrupts */
Rajendra Nayakef871432009-11-23 08:59:18 -0800510 dev->iestate = (OMAP_I2C_IE_XRDY | OMAP_I2C_IE_RRDY |
Tony Lindgrenc1a473b2008-11-21 13:39:47 -0800511 OMAP_I2C_IE_ARDY | OMAP_I2C_IE_NACK |
512 OMAP_I2C_IE_AL) | ((dev->fifo_size) ?
Rajendra Nayakef871432009-11-23 08:59:18 -0800513 (OMAP_I2C_IE_RDR | OMAP_I2C_IE_XDR) : 0);
514 omap_i2c_write_reg(dev, OMAP_I2C_IE_REG, dev->iestate);
515 if (cpu_is_omap34xx()) {
516 dev->pscstate = psc;
517 dev->scllstate = scll;
518 dev->sclhstate = sclh;
519 dev->bufstate = buf;
520 }
Komal Shah010d442c42006-08-13 23:44:09 +0200521 return 0;
522}
523
524/*
525 * Waiting on Bus Busy
526 */
527static int omap_i2c_wait_for_bb(struct omap_i2c_dev *dev)
528{
529 unsigned long timeout;
530
531 timeout = jiffies + OMAP_I2C_TIMEOUT;
532 while (omap_i2c_read_reg(dev, OMAP_I2C_STAT_REG) & OMAP_I2C_STAT_BB) {
533 if (time_after(jiffies, timeout)) {
534 dev_warn(dev->dev, "timeout waiting for bus ready\n");
535 return -ETIMEDOUT;
536 }
537 msleep(1);
538 }
539
540 return 0;
541}
542
543/*
544 * Low level master read/write transaction.
545 */
546static int omap_i2c_xfer_msg(struct i2c_adapter *adap,
547 struct i2c_msg *msg, int stop)
548{
549 struct omap_i2c_dev *dev = i2c_get_adapdata(adap);
550 int r;
551 u16 w;
552
553 dev_dbg(dev->dev, "addr: 0x%04x, len: %d, flags: 0x%x, stop: %d\n",
554 msg->addr, msg->len, msg->flags, stop);
555
556 if (msg->len == 0)
557 return -EINVAL;
558
559 omap_i2c_write_reg(dev, OMAP_I2C_SA_REG, msg->addr);
560
561 /* REVISIT: Could the STB bit of I2C_CON be used with probing? */
562 dev->buf = msg->buf;
563 dev->buf_len = msg->len;
564
565 omap_i2c_write_reg(dev, OMAP_I2C_CNT_REG, dev->buf_len);
566
Nishanth Menonb6ee52c2008-11-21 13:39:46 -0800567 /* Clear the FIFO Buffers */
568 w = omap_i2c_read_reg(dev, OMAP_I2C_BUF_REG);
569 w |= OMAP_I2C_BUF_RXFIF_CLR | OMAP_I2C_BUF_TXFIF_CLR;
570 omap_i2c_write_reg(dev, OMAP_I2C_BUF_REG, w);
571
Komal Shah010d442c42006-08-13 23:44:09 +0200572 init_completion(&dev->cmd_complete);
573 dev->cmd_err = 0;
574
575 w = OMAP_I2C_CON_EN | OMAP_I2C_CON_MST | OMAP_I2C_CON_STT;
Syed Mohammed Khasim4574eb62008-11-21 13:39:45 -0800576
577 /* High speed configuration */
578 if (dev->speed > 400)
Nishanth Menonb6ee52c2008-11-21 13:39:46 -0800579 w |= OMAP_I2C_CON_OPMODE_HS;
Syed Mohammed Khasim4574eb62008-11-21 13:39:45 -0800580
Komal Shah010d442c42006-08-13 23:44:09 +0200581 if (msg->flags & I2C_M_TEN)
582 w |= OMAP_I2C_CON_XA;
583 if (!(msg->flags & I2C_M_RD))
584 w |= OMAP_I2C_CON_TRX;
Tony Lindgrenc1a473b2008-11-21 13:39:47 -0800585
Nishanth Menonb6ee52c2008-11-21 13:39:46 -0800586 if (!dev->b_hw && stop)
Komal Shah010d442c42006-08-13 23:44:09 +0200587 w |= OMAP_I2C_CON_STP;
Tony Lindgrenc1a473b2008-11-21 13:39:47 -0800588
Komal Shah010d442c42006-08-13 23:44:09 +0200589 omap_i2c_write_reg(dev, OMAP_I2C_CON_REG, w);
590
Jarkko Nikulab7af3492008-11-21 13:39:45 -0800591 /*
Nishanth Menonb6ee52c2008-11-21 13:39:46 -0800592 * Don't write stt and stp together on some hardware.
593 */
594 if (dev->b_hw && stop) {
595 unsigned long delay = jiffies + OMAP_I2C_TIMEOUT;
596 u16 con = omap_i2c_read_reg(dev, OMAP_I2C_CON_REG);
597 while (con & OMAP_I2C_CON_STT) {
598 con = omap_i2c_read_reg(dev, OMAP_I2C_CON_REG);
599
600 /* Let the user know if i2c is in a bad state */
601 if (time_after(jiffies, delay)) {
602 dev_err(dev->dev, "controller timed out "
603 "waiting for start condition to finish\n");
604 return -ETIMEDOUT;
605 }
606 cpu_relax();
607 }
608
609 w |= OMAP_I2C_CON_STP;
610 w &= ~OMAP_I2C_CON_STT;
611 omap_i2c_write_reg(dev, OMAP_I2C_CON_REG, w);
612 }
613
614 /*
Jarkko Nikulab7af3492008-11-21 13:39:45 -0800615 * REVISIT: We should abort the transfer on signals, but the bus goes
616 * into arbitration and we're currently unable to recover from it.
617 */
Kalle Jokiniemi20c9d2c2010-05-11 11:35:08 -0700618 if (dev->set_mpu_wkup_lat != NULL)
619 dev->set_mpu_wkup_lat(dev->dev, dev->latency);
Jarkko Nikulab7af3492008-11-21 13:39:45 -0800620 r = wait_for_completion_timeout(&dev->cmd_complete,
621 OMAP_I2C_TIMEOUT);
Kalle Jokiniemi20c9d2c2010-05-11 11:35:08 -0700622 if (dev->set_mpu_wkup_lat != NULL)
623 dev->set_mpu_wkup_lat(dev->dev, -1);
Komal Shah010d442c42006-08-13 23:44:09 +0200624 dev->buf_len = 0;
625 if (r < 0)
626 return r;
627 if (r == 0) {
628 dev_err(dev->dev, "controller timed out\n");
629 omap_i2c_init(dev);
630 return -ETIMEDOUT;
631 }
632
633 if (likely(!dev->cmd_err))
634 return 0;
635
636 /* We have an error */
637 if (dev->cmd_err & (OMAP_I2C_STAT_AL | OMAP_I2C_STAT_ROVR |
638 OMAP_I2C_STAT_XUDF)) {
639 omap_i2c_init(dev);
640 return -EIO;
641 }
642
643 if (dev->cmd_err & OMAP_I2C_STAT_NACK) {
644 if (msg->flags & I2C_M_IGNORE_NAK)
645 return 0;
646 if (stop) {
647 w = omap_i2c_read_reg(dev, OMAP_I2C_CON_REG);
648 w |= OMAP_I2C_CON_STP;
649 omap_i2c_write_reg(dev, OMAP_I2C_CON_REG, w);
650 }
651 return -EREMOTEIO;
652 }
653 return -EIO;
654}
655
656
657/*
658 * Prepare controller for a transaction and call omap_i2c_xfer_msg
659 * to do the work during IRQ processing.
660 */
661static int
662omap_i2c_xfer(struct i2c_adapter *adap, struct i2c_msg msgs[], int num)
663{
664 struct omap_i2c_dev *dev = i2c_get_adapdata(adap);
665 int i;
666 int r;
667
Tony Lindgrenf08ac4e2008-03-23 20:28:20 +0100668 omap_i2c_unidle(dev);
Komal Shah010d442c42006-08-13 23:44:09 +0200669
Tony Lindgrenc1a473b2008-11-21 13:39:47 -0800670 r = omap_i2c_wait_for_bb(dev);
671 if (r < 0)
Komal Shah010d442c42006-08-13 23:44:09 +0200672 goto out;
673
674 for (i = 0; i < num; i++) {
675 r = omap_i2c_xfer_msg(adap, &msgs[i], (i == (num - 1)));
676 if (r != 0)
677 break;
678 }
679
680 if (r == 0)
681 r = num;
682out:
Tony Lindgrenf08ac4e2008-03-23 20:28:20 +0100683 omap_i2c_idle(dev);
Komal Shah010d442c42006-08-13 23:44:09 +0200684 return r;
685}
686
687static u32
688omap_i2c_func(struct i2c_adapter *adap)
689{
690 return I2C_FUNC_I2C | (I2C_FUNC_SMBUS_EMUL & ~I2C_FUNC_SMBUS_QUICK);
691}
692
693static inline void
694omap_i2c_complete_cmd(struct omap_i2c_dev *dev, u16 err)
695{
696 dev->cmd_err |= err;
697 complete(&dev->cmd_complete);
698}
699
700static inline void
701omap_i2c_ack_stat(struct omap_i2c_dev *dev, u16 stat)
702{
703 omap_i2c_write_reg(dev, OMAP_I2C_STAT_REG, stat);
704}
705
manjugk manjugkf3083d92010-05-11 11:35:20 -0700706static inline void i2c_omap_errata_i207(struct omap_i2c_dev *dev, u16 stat)
707{
708 /*
709 * I2C Errata(Errata Nos. OMAP2: 1.67, OMAP3: 1.8)
710 * Not applicable for OMAP4.
711 * Under certain rare conditions, RDR could be set again
712 * when the bus is busy, then ignore the interrupt and
713 * clear the interrupt.
714 */
715 if (stat & OMAP_I2C_STAT_RDR) {
716 /* Step 1: If RDR is set, clear it */
717 omap_i2c_ack_stat(dev, OMAP_I2C_STAT_RDR);
718
719 /* Step 2: */
720 if (!(omap_i2c_read_reg(dev, OMAP_I2C_STAT_REG)
721 & OMAP_I2C_STAT_BB)) {
722
723 /* Step 3: */
724 if (omap_i2c_read_reg(dev, OMAP_I2C_STAT_REG)
725 & OMAP_I2C_STAT_RDR) {
726 omap_i2c_ack_stat(dev, OMAP_I2C_STAT_RDR);
727 dev_dbg(dev->dev, "RDR when bus is busy.\n");
728 }
729
730 }
731 }
732}
733
Paul Walmsley43469d8e2008-11-21 13:39:47 -0800734/* rev1 devices are apparently only on some 15xx */
735#ifdef CONFIG_ARCH_OMAP15XX
736
Komal Shah010d442c42006-08-13 23:44:09 +0200737static irqreturn_t
David Howells7d12e782006-10-05 14:55:46 +0100738omap_i2c_rev1_isr(int this_irq, void *dev_id)
Komal Shah010d442c42006-08-13 23:44:09 +0200739{
740 struct omap_i2c_dev *dev = dev_id;
741 u16 iv, w;
742
Tony Lindgrenf08ac4e2008-03-23 20:28:20 +0100743 if (dev->idle)
744 return IRQ_NONE;
745
Komal Shah010d442c42006-08-13 23:44:09 +0200746 iv = omap_i2c_read_reg(dev, OMAP_I2C_IV_REG);
747 switch (iv) {
748 case 0x00: /* None */
749 break;
750 case 0x01: /* Arbitration lost */
751 dev_err(dev->dev, "Arbitration lost\n");
752 omap_i2c_complete_cmd(dev, OMAP_I2C_STAT_AL);
753 break;
754 case 0x02: /* No acknowledgement */
755 omap_i2c_complete_cmd(dev, OMAP_I2C_STAT_NACK);
756 omap_i2c_write_reg(dev, OMAP_I2C_CON_REG, OMAP_I2C_CON_STP);
757 break;
758 case 0x03: /* Register access ready */
759 omap_i2c_complete_cmd(dev, 0);
760 break;
761 case 0x04: /* Receive data ready */
762 if (dev->buf_len) {
763 w = omap_i2c_read_reg(dev, OMAP_I2C_DATA_REG);
764 *dev->buf++ = w;
765 dev->buf_len--;
766 if (dev->buf_len) {
767 *dev->buf++ = w >> 8;
768 dev->buf_len--;
769 }
770 } else
771 dev_err(dev->dev, "RRDY IRQ while no data requested\n");
772 break;
773 case 0x05: /* Transmit data ready */
774 if (dev->buf_len) {
775 w = *dev->buf++;
776 dev->buf_len--;
777 if (dev->buf_len) {
778 w |= *dev->buf++ << 8;
779 dev->buf_len--;
780 }
781 omap_i2c_write_reg(dev, OMAP_I2C_DATA_REG, w);
782 } else
783 dev_err(dev->dev, "XRDY IRQ while no data to send\n");
784 break;
785 default:
786 return IRQ_NONE;
787 }
788
789 return IRQ_HANDLED;
790}
Paul Walmsley43469d8e2008-11-21 13:39:47 -0800791#else
Tony Lindgrenc1a473b2008-11-21 13:39:47 -0800792#define omap_i2c_rev1_isr NULL
Paul Walmsley43469d8e2008-11-21 13:39:47 -0800793#endif
Komal Shah010d442c42006-08-13 23:44:09 +0200794
Alexander Shishkin2dd151a2010-05-11 11:35:14 -0700795/*
796 * OMAP3430 Errata 1.153: When an XRDY/XDR is hit, wait for XUDF before writing
797 * data to DATA_REG. Otherwise some data bytes can be lost while transferring
798 * them from the memory to the I2C interface.
799 */
800static int errata_omap3_1p153(struct omap_i2c_dev *dev, u16 *stat, int *err)
801{
Alexander Shishkine9f59b92010-05-11 11:35:17 -0700802 unsigned long timeout = 10000;
803
804 while (--timeout && !(*stat & OMAP_I2C_STAT_XUDF)) {
Alexander Shishkin2dd151a2010-05-11 11:35:14 -0700805 if (*stat & (OMAP_I2C_STAT_NACK | OMAP_I2C_STAT_AL)) {
806 omap_i2c_ack_stat(dev, *stat & (OMAP_I2C_STAT_XRDY |
807 OMAP_I2C_STAT_XDR));
808 *err |= OMAP_I2C_STAT_XUDF;
809 return -ETIMEDOUT;
810 }
Alexander Shishkine9f59b92010-05-11 11:35:17 -0700811
Alexander Shishkin2dd151a2010-05-11 11:35:14 -0700812 cpu_relax();
813 *stat = omap_i2c_read_reg(dev, OMAP_I2C_STAT_REG);
814 }
815
Alexander Shishkine9f59b92010-05-11 11:35:17 -0700816 if (!timeout) {
817 dev_err(dev->dev, "timeout waiting on XUDF bit\n");
818 return 0;
819 }
820
Alexander Shishkin2dd151a2010-05-11 11:35:14 -0700821 return 0;
822}
823
Komal Shah010d442c42006-08-13 23:44:09 +0200824static irqreturn_t
David Howells7d12e782006-10-05 14:55:46 +0100825omap_i2c_isr(int this_irq, void *dev_id)
Komal Shah010d442c42006-08-13 23:44:09 +0200826{
827 struct omap_i2c_dev *dev = dev_id;
828 u16 bits;
829 u16 stat, w;
Nishanth Menonb6ee52c2008-11-21 13:39:46 -0800830 int err, count = 0;
Komal Shah010d442c42006-08-13 23:44:09 +0200831
Tony Lindgrenf08ac4e2008-03-23 20:28:20 +0100832 if (dev->idle)
833 return IRQ_NONE;
834
Komal Shah010d442c42006-08-13 23:44:09 +0200835 bits = omap_i2c_read_reg(dev, OMAP_I2C_IE_REG);
836 while ((stat = (omap_i2c_read_reg(dev, OMAP_I2C_STAT_REG))) & bits) {
837 dev_dbg(dev->dev, "IRQ (ISR = 0x%04x)\n", stat);
838 if (count++ == 100) {
839 dev_warn(dev->dev, "Too much work in one IRQ\n");
840 break;
841 }
842
Sonasath, Moizcd086d32009-07-21 10:15:12 -0500843 err = 0;
844complete:
Nishanth Menondcc4ec22009-08-20 11:21:14 -0500845 /*
846 * Ack the stat in one go, but [R/X]DR and [R/X]RDY should be
847 * acked after the data operation is complete.
848 * Ref: TRM SWPU114Q Figure 18-31
849 */
850 omap_i2c_write_reg(dev, OMAP_I2C_STAT_REG, stat &
851 ~(OMAP_I2C_STAT_RRDY | OMAP_I2C_STAT_RDR |
852 OMAP_I2C_STAT_XRDY | OMAP_I2C_STAT_XDR));
Komal Shah010d442c42006-08-13 23:44:09 +0200853
Nishanth Menonb6ee52c2008-11-21 13:39:46 -0800854 if (stat & OMAP_I2C_STAT_NACK) {
855 err |= OMAP_I2C_STAT_NACK;
856 omap_i2c_write_reg(dev, OMAP_I2C_CON_REG,
857 OMAP_I2C_CON_STP);
858 }
859 if (stat & OMAP_I2C_STAT_AL) {
860 dev_err(dev->dev, "Arbitration lost\n");
861 err |= OMAP_I2C_STAT_AL;
862 }
863 if (stat & (OMAP_I2C_STAT_ARDY | OMAP_I2C_STAT_NACK |
Sonasath, Moiz04c688d2009-07-21 10:14:40 -0500864 OMAP_I2C_STAT_AL)) {
Moiz Sonasathdd11976a2009-08-20 11:21:15 -0500865 omap_i2c_ack_stat(dev, stat &
866 (OMAP_I2C_STAT_RRDY | OMAP_I2C_STAT_RDR |
867 OMAP_I2C_STAT_XRDY | OMAP_I2C_STAT_XDR));
Nishanth Menonb6ee52c2008-11-21 13:39:46 -0800868 omap_i2c_complete_cmd(dev, err);
Sonasath, Moiz04c688d2009-07-21 10:14:40 -0500869 return IRQ_HANDLED;
870 }
Nishanth Menonb6ee52c2008-11-21 13:39:46 -0800871 if (stat & (OMAP_I2C_STAT_RRDY | OMAP_I2C_STAT_RDR)) {
872 u8 num_bytes = 1;
manjugk manjugkf3083d92010-05-11 11:35:20 -0700873
874 if (dev->errata & I2C_OMAP_ERRATA_I207)
875 i2c_omap_errata_i207(dev, stat);
876
Nishanth Menonb6ee52c2008-11-21 13:39:46 -0800877 if (dev->fifo_size) {
878 if (stat & OMAP_I2C_STAT_RRDY)
879 num_bytes = dev->fifo_size;
Sonasath, Moizbfb6b652009-07-21 10:14:06 -0500880 else /* read RXSTAT on RDR interrupt */
881 num_bytes = (omap_i2c_read_reg(dev,
882 OMAP_I2C_BUFSTAT_REG)
883 >> 8) & 0x3F;
Nishanth Menonb6ee52c2008-11-21 13:39:46 -0800884 }
885 while (num_bytes) {
886 num_bytes--;
887 w = omap_i2c_read_reg(dev, OMAP_I2C_DATA_REG);
888 if (dev->buf_len) {
889 *dev->buf++ = w;
890 dev->buf_len--;
Santosh Shilimkarf38e66e2010-05-11 11:35:04 -0700891 /*
892 * Data reg in 2430, omap3 and
893 * omap4 is 8 bit wide
894 */
895 if (cpu_class_is_omap1() ||
896 cpu_is_omap2420()) {
Nishanth Menonb6ee52c2008-11-21 13:39:46 -0800897 if (dev->buf_len) {
898 *dev->buf++ = w >> 8;
899 dev->buf_len--;
900 }
901 }
902 } else {
903 if (stat & OMAP_I2C_STAT_RRDY)
904 dev_err(dev->dev,
905 "RRDY IRQ while no data"
906 " requested\n");
907 if (stat & OMAP_I2C_STAT_RDR)
908 dev_err(dev->dev,
909 "RDR IRQ while no data"
910 " requested\n");
911 break;
912 }
913 }
914 omap_i2c_ack_stat(dev,
915 stat & (OMAP_I2C_STAT_RRDY | OMAP_I2C_STAT_RDR));
Komal Shah010d442c42006-08-13 23:44:09 +0200916 continue;
917 }
Nishanth Menonb6ee52c2008-11-21 13:39:46 -0800918 if (stat & (OMAP_I2C_STAT_XRDY | OMAP_I2C_STAT_XDR)) {
919 u8 num_bytes = 1;
920 if (dev->fifo_size) {
921 if (stat & OMAP_I2C_STAT_XRDY)
922 num_bytes = dev->fifo_size;
Sonasath, Moizbfb6b652009-07-21 10:14:06 -0500923 else /* read TXSTAT on XDR interrupt */
Nishanth Menonb6ee52c2008-11-21 13:39:46 -0800924 num_bytes = omap_i2c_read_reg(dev,
Sonasath, Moizbfb6b652009-07-21 10:14:06 -0500925 OMAP_I2C_BUFSTAT_REG)
926 & 0x3F;
Nishanth Menonb6ee52c2008-11-21 13:39:46 -0800927 }
928 while (num_bytes) {
929 num_bytes--;
930 w = 0;
Komal Shah010d442c42006-08-13 23:44:09 +0200931 if (dev->buf_len) {
Nishanth Menonb6ee52c2008-11-21 13:39:46 -0800932 w = *dev->buf++;
Komal Shah010d442c42006-08-13 23:44:09 +0200933 dev->buf_len--;
Santosh Shilimkarf38e66e2010-05-11 11:35:04 -0700934 /*
935 * Data reg in 2430, omap3 and
936 * omap4 is 8 bit wide
937 */
938 if (cpu_class_is_omap1() ||
939 cpu_is_omap2420()) {
Nishanth Menonb6ee52c2008-11-21 13:39:46 -0800940 if (dev->buf_len) {
941 w |= *dev->buf++ << 8;
942 dev->buf_len--;
943 }
944 }
945 } else {
946 if (stat & OMAP_I2C_STAT_XRDY)
947 dev_err(dev->dev,
948 "XRDY IRQ while no "
949 "data to send\n");
950 if (stat & OMAP_I2C_STAT_XDR)
951 dev_err(dev->dev,
952 "XDR IRQ while no "
953 "data to send\n");
954 break;
Komal Shah010d442c42006-08-13 23:44:09 +0200955 }
Sonasath, Moizcd086d32009-07-21 10:15:12 -0500956
Alexander Shishkin2dd151a2010-05-11 11:35:14 -0700957 if ((dev->rev <= OMAP_I2C_REV_ON_3430) &&
958 errata_omap3_1p153(dev, &stat, &err))
959 goto complete;
Sonasath, Moizcd086d32009-07-21 10:15:12 -0500960
Nishanth Menonb6ee52c2008-11-21 13:39:46 -0800961 omap_i2c_write_reg(dev, OMAP_I2C_DATA_REG, w);
962 }
963 omap_i2c_ack_stat(dev,
964 stat & (OMAP_I2C_STAT_XRDY | OMAP_I2C_STAT_XDR));
Komal Shah010d442c42006-08-13 23:44:09 +0200965 continue;
966 }
967 if (stat & OMAP_I2C_STAT_ROVR) {
968 dev_err(dev->dev, "Receive overrun\n");
969 dev->cmd_err |= OMAP_I2C_STAT_ROVR;
970 }
971 if (stat & OMAP_I2C_STAT_XUDF) {
Nishanth Menonb6ee52c2008-11-21 13:39:46 -0800972 dev_err(dev->dev, "Transmit underflow\n");
Komal Shah010d442c42006-08-13 23:44:09 +0200973 dev->cmd_err |= OMAP_I2C_STAT_XUDF;
974 }
Komal Shah010d442c42006-08-13 23:44:09 +0200975 }
976
977 return count ? IRQ_HANDLED : IRQ_NONE;
978}
979
Jean Delvare8f9082c2006-09-03 22:39:46 +0200980static const struct i2c_algorithm omap_i2c_algo = {
Komal Shah010d442c42006-08-13 23:44:09 +0200981 .master_xfer = omap_i2c_xfer,
982 .functionality = omap_i2c_func,
983};
984
Uwe Kleine-König1139aea2010-02-04 20:56:53 +0100985static int __devinit
Komal Shah010d442c42006-08-13 23:44:09 +0200986omap_i2c_probe(struct platform_device *pdev)
987{
988 struct omap_i2c_dev *dev;
989 struct i2c_adapter *adap;
990 struct resource *mem, *irq, *ioarea;
Kalle Jokiniemi20c9d2c2010-05-11 11:35:08 -0700991 struct omap_i2c_bus_platform_data *pdata = pdev->dev.platform_data;
Ben Dookse3552042008-12-16 22:08:08 +0000992 irq_handler_t isr;
Komal Shah010d442c42006-08-13 23:44:09 +0200993 int r;
Chandra shekhar3d522fb2008-11-21 13:39:46 -0800994 u32 speed = 0;
Komal Shah010d442c42006-08-13 23:44:09 +0200995
996 /* NOTE: driver uses the static register mapping */
997 mem = platform_get_resource(pdev, IORESOURCE_MEM, 0);
998 if (!mem) {
999 dev_err(&pdev->dev, "no mem resource?\n");
1000 return -ENODEV;
1001 }
1002 irq = platform_get_resource(pdev, IORESOURCE_IRQ, 0);
1003 if (!irq) {
1004 dev_err(&pdev->dev, "no irq resource?\n");
1005 return -ENODEV;
1006 }
1007
Julia Lawall59330822009-07-05 08:37:50 +02001008 ioarea = request_mem_region(mem->start, resource_size(mem),
Komal Shah010d442c42006-08-13 23:44:09 +02001009 pdev->name);
1010 if (!ioarea) {
1011 dev_err(&pdev->dev, "I2C region already claimed\n");
1012 return -EBUSY;
1013 }
1014
Komal Shah010d442c42006-08-13 23:44:09 +02001015 dev = kzalloc(sizeof(struct omap_i2c_dev), GFP_KERNEL);
1016 if (!dev) {
1017 r = -ENOMEM;
1018 goto err_release_region;
1019 }
1020
Kalle Jokiniemi20c9d2c2010-05-11 11:35:08 -07001021 if (pdata != NULL) {
1022 speed = pdata->clkrate;
1023 dev->set_mpu_wkup_lat = pdata->set_mpu_wkup_lat;
1024 } else {
1025 speed = 100; /* Default speed */
1026 dev->set_mpu_wkup_lat = NULL;
1027 }
Syed Mohammed Khasim4574eb62008-11-21 13:39:45 -08001028
Chandra shekhar3d522fb2008-11-21 13:39:46 -08001029 dev->speed = speed;
Paul Walmsley3831f152008-11-21 13:39:47 -08001030 dev->idle = 1;
Komal Shah010d442c42006-08-13 23:44:09 +02001031 dev->dev = &pdev->dev;
1032 dev->irq = irq->start;
Linus Walleijc6ffdde2009-06-14 00:20:36 +02001033 dev->base = ioremap(mem->start, resource_size(mem));
Russell King55c381e2008-09-04 14:07:22 +01001034 if (!dev->base) {
1035 r = -ENOMEM;
1036 goto err_free_mem;
1037 }
1038
Komal Shah010d442c42006-08-13 23:44:09 +02001039 platform_set_drvdata(pdev, dev);
1040
Mika Westerberg7c6bd202010-03-23 12:12:56 +02001041 if (cpu_is_omap7xx())
1042 dev->reg_shift = 1;
Santosh Shilimkarf38e66e2010-05-11 11:35:04 -07001043 else if (cpu_is_omap44xx())
1044 dev->reg_shift = 0;
Mika Westerberg7c6bd202010-03-23 12:12:56 +02001045 else
1046 dev->reg_shift = 2;
1047
Komal Shah010d442c42006-08-13 23:44:09 +02001048 if ((r = omap_i2c_get_clocks(dev)) != 0)
Russell King55c381e2008-09-04 14:07:22 +01001049 goto err_iounmap;
Komal Shah010d442c42006-08-13 23:44:09 +02001050
Santosh Shilimkarf38e66e2010-05-11 11:35:04 -07001051 if (cpu_is_omap44xx())
1052 dev->regs = (u8 *) omap4_reg_map;
1053 else
1054 dev->regs = (u8 *) reg_map;
1055
Tony Lindgrenf08ac4e2008-03-23 20:28:20 +01001056 omap_i2c_unidle(dev);
Komal Shah010d442c42006-08-13 23:44:09 +02001057
Paul Walmsley9c76b872008-11-21 13:39:55 -08001058 dev->rev = omap_i2c_read_reg(dev, OMAP_I2C_REV_REG) & 0xff;
Komal Shah010d442c42006-08-13 23:44:09 +02001059
Santosh Shilimkarf38e66e2010-05-11 11:35:04 -07001060 if (!(cpu_class_is_omap1() || cpu_is_omap2420())) {
Nishanth Menonb6ee52c2008-11-21 13:39:46 -08001061 u16 s;
1062
1063 /* Set up the fifo size - Get total size */
1064 s = (omap_i2c_read_reg(dev, OMAP_I2C_BUFSTAT_REG) >> 14) & 0x3;
1065 dev->fifo_size = 0x8 << s;
1066
1067 /*
1068 * Set up notification threshold as half the total available
1069 * size. This is to ensure that we can handle the status on int
1070 * call back latencies.
1071 */
Santosh Shilimkarf38e66e2010-05-11 11:35:04 -07001072 if (dev->rev >= OMAP_I2C_REV_ON_4430) {
1073 dev->fifo_size = 0;
1074 dev->b_hw = 0; /* Disable hardware fixes */
1075 } else {
1076 dev->fifo_size = (dev->fifo_size / 2);
1077 dev->b_hw = 1; /* Enable hardware fixes */
1078 }
Kalle Jokiniemi20c9d2c2010-05-11 11:35:08 -07001079 /* calculate wakeup latency constraint for MPU */
1080 if (dev->set_mpu_wkup_lat != NULL)
1081 dev->latency = (1000000 * dev->fifo_size) /
1082 (1000 * speed / 8);
Nishanth Menonb6ee52c2008-11-21 13:39:46 -08001083 }
1084
Komal Shah010d442c42006-08-13 23:44:09 +02001085 /* reset ASAP, clearing any IRQs */
1086 omap_i2c_init(dev);
1087
Paul Walmsley9c76b872008-11-21 13:39:55 -08001088 isr = (dev->rev < OMAP_I2C_REV_2) ? omap_i2c_rev1_isr : omap_i2c_isr;
1089 r = request_irq(dev->irq, isr, 0, pdev->name, dev);
Komal Shah010d442c42006-08-13 23:44:09 +02001090
1091 if (r) {
1092 dev_err(dev->dev, "failure requesting irq %i\n", dev->irq);
1093 goto err_unuse_clocks;
1094 }
Paul Walmsley9c76b872008-11-21 13:39:55 -08001095
Komal Shah010d442c42006-08-13 23:44:09 +02001096 dev_info(dev->dev, "bus %d rev%d.%d at %d kHz\n",
Paul Walmsley9c76b872008-11-21 13:39:55 -08001097 pdev->id, dev->rev >> 4, dev->rev & 0xf, dev->speed);
Komal Shah010d442c42006-08-13 23:44:09 +02001098
Paul Walmsley3831f152008-11-21 13:39:47 -08001099 omap_i2c_idle(dev);
1100
Komal Shah010d442c42006-08-13 23:44:09 +02001101 adap = &dev->adapter;
1102 i2c_set_adapdata(adap, dev);
1103 adap->owner = THIS_MODULE;
1104 adap->class = I2C_CLASS_HWMON;
Roel Kluin783fd6f2009-07-17 15:24:00 +02001105 strlcpy(adap->name, "OMAP I2C adapter", sizeof(adap->name));
Komal Shah010d442c42006-08-13 23:44:09 +02001106 adap->algo = &omap_i2c_algo;
1107 adap->dev.parent = &pdev->dev;
1108
1109 /* i2c device drivers may be active on return from add_adapter() */
David Brownell7c175492007-05-01 23:26:32 +02001110 adap->nr = pdev->id;
1111 r = i2c_add_numbered_adapter(adap);
Komal Shah010d442c42006-08-13 23:44:09 +02001112 if (r) {
1113 dev_err(dev->dev, "failure adding adapter\n");
1114 goto err_free_irq;
1115 }
1116
Komal Shah010d442c42006-08-13 23:44:09 +02001117 return 0;
1118
1119err_free_irq:
1120 free_irq(dev->irq, dev);
1121err_unuse_clocks:
Tony Lindgren3e397522008-01-14 21:53:30 +01001122 omap_i2c_write_reg(dev, OMAP_I2C_CON_REG, 0);
Tony Lindgrenf08ac4e2008-03-23 20:28:20 +01001123 omap_i2c_idle(dev);
Komal Shah010d442c42006-08-13 23:44:09 +02001124 omap_i2c_put_clocks(dev);
Russell King55c381e2008-09-04 14:07:22 +01001125err_iounmap:
1126 iounmap(dev->base);
Komal Shah010d442c42006-08-13 23:44:09 +02001127err_free_mem:
1128 platform_set_drvdata(pdev, NULL);
1129 kfree(dev);
1130err_release_region:
Julia Lawall59330822009-07-05 08:37:50 +02001131 release_mem_region(mem->start, resource_size(mem));
Komal Shah010d442c42006-08-13 23:44:09 +02001132
1133 return r;
1134}
1135
1136static int
1137omap_i2c_remove(struct platform_device *pdev)
1138{
1139 struct omap_i2c_dev *dev = platform_get_drvdata(pdev);
1140 struct resource *mem;
1141
1142 platform_set_drvdata(pdev, NULL);
1143
1144 free_irq(dev->irq, dev);
1145 i2c_del_adapter(&dev->adapter);
1146 omap_i2c_write_reg(dev, OMAP_I2C_CON_REG, 0);
1147 omap_i2c_put_clocks(dev);
Russell King55c381e2008-09-04 14:07:22 +01001148 iounmap(dev->base);
Komal Shah010d442c42006-08-13 23:44:09 +02001149 kfree(dev);
1150 mem = platform_get_resource(pdev, IORESOURCE_MEM, 0);
Julia Lawall59330822009-07-05 08:37:50 +02001151 release_mem_region(mem->start, resource_size(mem));
Komal Shah010d442c42006-08-13 23:44:09 +02001152 return 0;
1153}
1154
1155static struct platform_driver omap_i2c_driver = {
1156 .probe = omap_i2c_probe,
1157 .remove = omap_i2c_remove,
1158 .driver = {
1159 .name = "i2c_omap",
1160 .owner = THIS_MODULE,
1161 },
1162};
1163
1164/* I2C may be needed to bring up other drivers */
1165static int __init
1166omap_i2c_init_driver(void)
1167{
1168 return platform_driver_register(&omap_i2c_driver);
1169}
1170subsys_initcall(omap_i2c_init_driver);
1171
1172static void __exit omap_i2c_exit_driver(void)
1173{
1174 platform_driver_unregister(&omap_i2c_driver);
1175}
1176module_exit(omap_i2c_exit_driver);
1177
1178MODULE_AUTHOR("MontaVista Software, Inc. (and others)");
1179MODULE_DESCRIPTION("TI OMAP I2C bus adapter");
1180MODULE_LICENSE("GPL");
Kay Sieversadd8eda2008-04-22 22:16:49 +02001181MODULE_ALIAS("platform:i2c_omap");