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i2c: omap: simplify omap_i2c_ack_stat()
[linux-2.6.git] / drivers / i2c / busses / i2c-omap.c
blobf24eae9f7f1eb998fb1af608364b3e1818f024d0
1 /*
2 * TI OMAP I2C master mode driver
3 *
4 * Copyright (C) 2003 MontaVista Software, Inc.
5 * Copyright (C) 2005 Nokia Corporation
6 * Copyright (C) 2004 - 2007 Texas Instruments.
7 *
8 * 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>
15 *
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>
39 #include <linux/io.h>
40 #include <linux/of.h>
41 #include <linux/of_i2c.h>
42 #include <linux/of_device.h>
43 #include <linux/slab.h>
44 #include <linux/i2c-omap.h>
45 #include <linux/pm_runtime.h>
46
47 /* I2C controller revisions */
48 #define OMAP_I2C_OMAP1_REV_2 0x20
49
50 /* I2C controller revisions present on specific hardware */
51 #define OMAP_I2C_REV_ON_2430 0x36
52 #define OMAP_I2C_REV_ON_3430_3530 0x3C
53 #define OMAP_I2C_REV_ON_3630_4430 0x40
54
55 /* timeout waiting for the controller to respond */
56 #define OMAP_I2C_TIMEOUT (msecs_to_jiffies(1000))
57
58 /* For OMAP3 I2C_IV has changed to I2C_WE (wakeup enable) */
59 enum {
60 OMAP_I2C_REV_REG = 0,
61 OMAP_I2C_IE_REG,
62 OMAP_I2C_STAT_REG,
63 OMAP_I2C_IV_REG,
64 OMAP_I2C_WE_REG,
65 OMAP_I2C_SYSS_REG,
66 OMAP_I2C_BUF_REG,
67 OMAP_I2C_CNT_REG,
68 OMAP_I2C_DATA_REG,
69 OMAP_I2C_SYSC_REG,
70 OMAP_I2C_CON_REG,
71 OMAP_I2C_OA_REG,
72 OMAP_I2C_SA_REG,
73 OMAP_I2C_PSC_REG,
74 OMAP_I2C_SCLL_REG,
75 OMAP_I2C_SCLH_REG,
76 OMAP_I2C_SYSTEST_REG,
77 OMAP_I2C_BUFSTAT_REG,
78 /* only on OMAP4430 */
79 OMAP_I2C_IP_V2_REVNB_LO,
80 OMAP_I2C_IP_V2_REVNB_HI,
81 OMAP_I2C_IP_V2_IRQSTATUS_RAW,
82 OMAP_I2C_IP_V2_IRQENABLE_SET,
83 OMAP_I2C_IP_V2_IRQENABLE_CLR,
84 };
85
86 /* I2C Interrupt Enable Register (OMAP_I2C_IE): */
87 #define OMAP_I2C_IE_XDR (1 << 14) /* TX Buffer drain int enable */
88 #define OMAP_I2C_IE_RDR (1 << 13) /* RX Buffer drain int enable */
89 #define OMAP_I2C_IE_XRDY (1 << 4) /* TX data ready int enable */
90 #define OMAP_I2C_IE_RRDY (1 << 3) /* RX data ready int enable */
91 #define OMAP_I2C_IE_ARDY (1 << 2) /* Access ready int enable */
92 #define OMAP_I2C_IE_NACK (1 << 1) /* No ack interrupt enable */
93 #define OMAP_I2C_IE_AL (1 << 0) /* Arbitration lost int ena */
94
95 /* I2C Status Register (OMAP_I2C_STAT): */
96 #define OMAP_I2C_STAT_XDR (1 << 14) /* TX Buffer draining */
97 #define OMAP_I2C_STAT_RDR (1 << 13) /* RX Buffer draining */
98 #define OMAP_I2C_STAT_BB (1 << 12) /* Bus busy */
99 #define OMAP_I2C_STAT_ROVR (1 << 11) /* Receive overrun */
100 #define OMAP_I2C_STAT_XUDF (1 << 10) /* Transmit underflow */
101 #define OMAP_I2C_STAT_AAS (1 << 9) /* Address as slave */
102 #define OMAP_I2C_STAT_AD0 (1 << 8) /* Address zero */
103 #define OMAP_I2C_STAT_XRDY (1 << 4) /* Transmit data ready */
104 #define OMAP_I2C_STAT_RRDY (1 << 3) /* Receive data ready */
105 #define OMAP_I2C_STAT_ARDY (1 << 2) /* Register access ready */
106 #define OMAP_I2C_STAT_NACK (1 << 1) /* No ack interrupt enable */
107 #define OMAP_I2C_STAT_AL (1 << 0) /* Arbitration lost int ena */
108
109 /* I2C WE wakeup enable register */
110 #define OMAP_I2C_WE_XDR_WE (1 << 14) /* TX drain wakup */
111 #define OMAP_I2C_WE_RDR_WE (1 << 13) /* RX drain wakeup */
112 #define OMAP_I2C_WE_AAS_WE (1 << 9) /* Address as slave wakeup*/
113 #define OMAP_I2C_WE_BF_WE (1 << 8) /* Bus free wakeup */
114 #define OMAP_I2C_WE_STC_WE (1 << 6) /* Start condition wakeup */
115 #define OMAP_I2C_WE_GC_WE (1 << 5) /* General call wakeup */
116 #define OMAP_I2C_WE_DRDY_WE (1 << 3) /* TX/RX data ready wakeup */
117 #define OMAP_I2C_WE_ARDY_WE (1 << 2) /* Reg access ready wakeup */
118 #define OMAP_I2C_WE_NACK_WE (1 << 1) /* No acknowledgment wakeup */
119 #define OMAP_I2C_WE_AL_WE (1 << 0) /* Arbitration lost wakeup */
120
121 #define OMAP_I2C_WE_ALL (OMAP_I2C_WE_XDR_WE | OMAP_I2C_WE_RDR_WE | \
122 OMAP_I2C_WE_AAS_WE | OMAP_I2C_WE_BF_WE | \
123 OMAP_I2C_WE_STC_WE | OMAP_I2C_WE_GC_WE | \
124 OMAP_I2C_WE_DRDY_WE | OMAP_I2C_WE_ARDY_WE | \
125 OMAP_I2C_WE_NACK_WE | OMAP_I2C_WE_AL_WE)
126
127 /* I2C Buffer Configuration Register (OMAP_I2C_BUF): */
128 #define OMAP_I2C_BUF_RDMA_EN (1 << 15) /* RX DMA channel enable */
129 #define OMAP_I2C_BUF_RXFIF_CLR (1 << 14) /* RX FIFO Clear */
130 #define OMAP_I2C_BUF_XDMA_EN (1 << 7) /* TX DMA channel enable */
131 #define OMAP_I2C_BUF_TXFIF_CLR (1 << 6) /* TX FIFO Clear */
132
133 /* I2C Configuration Register (OMAP_I2C_CON): */
134 #define OMAP_I2C_CON_EN (1 << 15) /* I2C module enable */
135 #define OMAP_I2C_CON_BE (1 << 14) /* Big endian mode */
136 #define OMAP_I2C_CON_OPMODE_HS (1 << 12) /* High Speed support */
137 #define OMAP_I2C_CON_STB (1 << 11) /* Start byte mode (master) */
138 #define OMAP_I2C_CON_MST (1 << 10) /* Master/slave mode */
139 #define OMAP_I2C_CON_TRX (1 << 9) /* TX/RX mode (master only) */
140 #define OMAP_I2C_CON_XA (1 << 8) /* Expand address */
141 #define OMAP_I2C_CON_RM (1 << 2) /* Repeat mode (master only) */
142 #define OMAP_I2C_CON_STP (1 << 1) /* Stop cond (master only) */
143 #define OMAP_I2C_CON_STT (1 << 0) /* Start condition (master) */
144
145 /* I2C SCL time value when Master */
146 #define OMAP_I2C_SCLL_HSSCLL 8
147 #define OMAP_I2C_SCLH_HSSCLH 8
148
149 /* I2C System Test Register (OMAP_I2C_SYSTEST): */
150 #ifdef DEBUG
151 #define OMAP_I2C_SYSTEST_ST_EN (1 << 15) /* System test enable */
152 #define OMAP_I2C_SYSTEST_FREE (1 << 14) /* Free running mode */
153 #define OMAP_I2C_SYSTEST_TMODE_MASK (3 << 12) /* Test mode select */
154 #define OMAP_I2C_SYSTEST_TMODE_SHIFT (12) /* Test mode select */
155 #define OMAP_I2C_SYSTEST_SCL_I (1 << 3) /* SCL line sense in */
156 #define OMAP_I2C_SYSTEST_SCL_O (1 << 2) /* SCL line drive out */
157 #define OMAP_I2C_SYSTEST_SDA_I (1 << 1) /* SDA line sense in */
158 #define OMAP_I2C_SYSTEST_SDA_O (1 << 0) /* SDA line drive out */
159 #endif
160
161 /* OCP_SYSSTATUS bit definitions */
162 #define SYSS_RESETDONE_MASK (1 << 0)
163
164 /* OCP_SYSCONFIG bit definitions */
165 #define SYSC_CLOCKACTIVITY_MASK (0x3 << 8)
166 #define SYSC_SIDLEMODE_MASK (0x3 << 3)
167 #define SYSC_ENAWAKEUP_MASK (1 << 2)
168 #define SYSC_SOFTRESET_MASK (1 << 1)
169 #define SYSC_AUTOIDLE_MASK (1 << 0)
170
171 #define SYSC_IDLEMODE_SMART 0x2
172 #define SYSC_CLOCKACTIVITY_FCLK 0x2
173
174 /* Errata definitions */
175 #define I2C_OMAP_ERRATA_I207 (1 << 0)
176 #define I2C_OMAP_ERRATA_I462 (1 << 1)
177
178 struct omap_i2c_dev {
179 struct device *dev;
180 void __iomem *base; /* virtual */
181 int irq;
182 int reg_shift; /* bit shift for I2C register addresses */
183 struct completion cmd_complete;
184 struct resource *ioarea;
185 u32 latency; /* maximum mpu wkup latency */
186 void (*set_mpu_wkup_lat)(struct device *dev,
187 long latency);
188 u32 speed; /* Speed of bus in kHz */
189 u32 dtrev; /* extra revision from DT */
190 u32 flags;
191 u16 cmd_err;
192 u8 *buf;
193 u8 *regs;
194 size_t buf_len;
195 struct i2c_adapter adapter;
196 u8 fifo_size; /* use as flag and value
197 * fifo_size==0 implies no fifo
198 * if set, should be trsh+1
199 */
200 u8 rev;
201 unsigned b_hw:1; /* bad h/w fixes */
202 u16 iestate; /* Saved interrupt register */
203 u16 pscstate;
204 u16 scllstate;
205 u16 sclhstate;
206 u16 bufstate;
207 u16 syscstate;
208 u16 westate;
209 u16 errata;
210 };
211
212 static const u8 reg_map_ip_v1[] = {
213 [OMAP_I2C_REV_REG] = 0x00,
214 [OMAP_I2C_IE_REG] = 0x01,
215 [OMAP_I2C_STAT_REG] = 0x02,
216 [OMAP_I2C_IV_REG] = 0x03,
217 [OMAP_I2C_WE_REG] = 0x03,
218 [OMAP_I2C_SYSS_REG] = 0x04,
219 [OMAP_I2C_BUF_REG] = 0x05,
220 [OMAP_I2C_CNT_REG] = 0x06,
221 [OMAP_I2C_DATA_REG] = 0x07,
222 [OMAP_I2C_SYSC_REG] = 0x08,
223 [OMAP_I2C_CON_REG] = 0x09,
224 [OMAP_I2C_OA_REG] = 0x0a,
225 [OMAP_I2C_SA_REG] = 0x0b,
226 [OMAP_I2C_PSC_REG] = 0x0c,
227 [OMAP_I2C_SCLL_REG] = 0x0d,
228 [OMAP_I2C_SCLH_REG] = 0x0e,
229 [OMAP_I2C_SYSTEST_REG] = 0x0f,
230 [OMAP_I2C_BUFSTAT_REG] = 0x10,
231 };
232
233 static const u8 reg_map_ip_v2[] = {
234 [OMAP_I2C_REV_REG] = 0x04,
235 [OMAP_I2C_IE_REG] = 0x2c,
236 [OMAP_I2C_STAT_REG] = 0x28,
237 [OMAP_I2C_IV_REG] = 0x34,
238 [OMAP_I2C_WE_REG] = 0x34,
239 [OMAP_I2C_SYSS_REG] = 0x90,
240 [OMAP_I2C_BUF_REG] = 0x94,
241 [OMAP_I2C_CNT_REG] = 0x98,
242 [OMAP_I2C_DATA_REG] = 0x9c,
243 [OMAP_I2C_SYSC_REG] = 0x10,
244 [OMAP_I2C_CON_REG] = 0xa4,
245 [OMAP_I2C_OA_REG] = 0xa8,
246 [OMAP_I2C_SA_REG] = 0xac,
247 [OMAP_I2C_PSC_REG] = 0xb0,
248 [OMAP_I2C_SCLL_REG] = 0xb4,
249 [OMAP_I2C_SCLH_REG] = 0xb8,
250 [OMAP_I2C_SYSTEST_REG] = 0xbC,
251 [OMAP_I2C_BUFSTAT_REG] = 0xc0,
252 [OMAP_I2C_IP_V2_REVNB_LO] = 0x00,
253 [OMAP_I2C_IP_V2_REVNB_HI] = 0x04,
254 [OMAP_I2C_IP_V2_IRQSTATUS_RAW] = 0x24,
255 [OMAP_I2C_IP_V2_IRQENABLE_SET] = 0x2c,
256 [OMAP_I2C_IP_V2_IRQENABLE_CLR] = 0x30,
257 };
258
259 static inline void omap_i2c_write_reg(struct omap_i2c_dev *i2c_dev,
260 int reg, u16 val)
261 {
262 __raw_writew(val, i2c_dev->base +
263 (i2c_dev->regs[reg] << i2c_dev->reg_shift));
264 }
265
266 static inline u16 omap_i2c_read_reg(struct omap_i2c_dev *i2c_dev, int reg)
267 {
268 return __raw_readw(i2c_dev->base +
269 (i2c_dev->regs[reg] << i2c_dev->reg_shift));
270 }
271
272 static int omap_i2c_init(struct omap_i2c_dev *dev)
273 {
274 u16 psc = 0, scll = 0, sclh = 0, buf = 0;
275 u16 fsscll = 0, fssclh = 0, hsscll = 0, hssclh = 0;
276 unsigned long fclk_rate = 12000000;
277 unsigned long timeout;
278 unsigned long internal_clk = 0;
279 struct clk *fclk;
280
281 if (dev->rev >= OMAP_I2C_OMAP1_REV_2) {
282 /* Disable I2C controller before soft reset */
283 omap_i2c_write_reg(dev, OMAP_I2C_CON_REG,
284 omap_i2c_read_reg(dev, OMAP_I2C_CON_REG) &
285 ~(OMAP_I2C_CON_EN));
286
287 omap_i2c_write_reg(dev, OMAP_I2C_SYSC_REG, SYSC_SOFTRESET_MASK);
288 /* For some reason we need to set the EN bit before the
289 * reset done bit gets set. */
290 timeout = jiffies + OMAP_I2C_TIMEOUT;
291 omap_i2c_write_reg(dev, OMAP_I2C_CON_REG, OMAP_I2C_CON_EN);
292 while (!(omap_i2c_read_reg(dev, OMAP_I2C_SYSS_REG) &
293 SYSS_RESETDONE_MASK)) {
294 if (time_after(jiffies, timeout)) {
295 dev_warn(dev->dev, "timeout waiting "
296 "for controller reset\n");
297 return -ETIMEDOUT;
298 }
299 msleep(1);
300 }
301
302 /* SYSC register is cleared by the reset; rewrite it */
303 if (dev->rev == OMAP_I2C_REV_ON_2430) {
304
305 omap_i2c_write_reg(dev, OMAP_I2C_SYSC_REG,
306 SYSC_AUTOIDLE_MASK);
307
308 } else if (dev->rev >= OMAP_I2C_REV_ON_3430_3530) {
309 dev->syscstate = SYSC_AUTOIDLE_MASK;
310 dev->syscstate |= SYSC_ENAWAKEUP_MASK;
311 dev->syscstate |= (SYSC_IDLEMODE_SMART <<
312 __ffs(SYSC_SIDLEMODE_MASK));
313 dev->syscstate |= (SYSC_CLOCKACTIVITY_FCLK <<
314 __ffs(SYSC_CLOCKACTIVITY_MASK));
315
316 omap_i2c_write_reg(dev, OMAP_I2C_SYSC_REG,
317 dev->syscstate);
318 /*
319 * Enabling all wakup sources to stop I2C freezing on
320 * WFI instruction.
321 * REVISIT: Some wkup sources might not be needed.
322 */
323 dev->westate = OMAP_I2C_WE_ALL;
324 omap_i2c_write_reg(dev, OMAP_I2C_WE_REG,
325 dev->westate);
326 }
327 }
328 omap_i2c_write_reg(dev, OMAP_I2C_CON_REG, 0);
329
330 if (dev->flags & OMAP_I2C_FLAG_ALWAYS_ARMXOR_CLK) {
331 /*
332 * The I2C functional clock is the armxor_ck, so there's
333 * no need to get "armxor_ck" separately. Now, if OMAP2420
334 * always returns 12MHz for the functional clock, we can
335 * do this bit unconditionally.
336 */
337 fclk = clk_get(dev->dev, "fck");
338 fclk_rate = clk_get_rate(fclk);
339 clk_put(fclk);
340
341 /* TRM for 5912 says the I2C clock must be prescaled to be
342 * between 7 - 12 MHz. The XOR input clock is typically
343 * 12, 13 or 19.2 MHz. So we should have code that produces:
344 *
345 * XOR MHz Divider Prescaler
346 * 12 1 0
347 * 13 2 1
348 * 19.2 2 1
349 */
350 if (fclk_rate > 12000000)
351 psc = fclk_rate / 12000000;
352 }
353
354 if (!(dev->flags & OMAP_I2C_FLAG_SIMPLE_CLOCK)) {
355
356 /*
357 * HSI2C controller internal clk rate should be 19.2 Mhz for
358 * HS and for all modes on 2430. On 34xx we can use lower rate
359 * to get longer filter period for better noise suppression.
360 * The filter is iclk (fclk for HS) period.
361 */
362 if (dev->speed > 400 ||
363 dev->flags & OMAP_I2C_FLAG_FORCE_19200_INT_CLK)
364 internal_clk = 19200;
365 else if (dev->speed > 100)
366 internal_clk = 9600;
367 else
368 internal_clk = 4000;
369 fclk = clk_get(dev->dev, "fck");
370 fclk_rate = clk_get_rate(fclk) / 1000;
371 clk_put(fclk);
372
373 /* Compute prescaler divisor */
374 psc = fclk_rate / internal_clk;
375 psc = psc - 1;
376
377 /* If configured for High Speed */
378 if (dev->speed > 400) {
379 unsigned long scl;
380
381 /* For first phase of HS mode */
382 scl = internal_clk / 400;
383 fsscll = scl - (scl / 3) - 7;
384 fssclh = (scl / 3) - 5;
385
386 /* For second phase of HS mode */
387 scl = fclk_rate / dev->speed;
388 hsscll = scl - (scl / 3) - 7;
389 hssclh = (scl / 3) - 5;
390 } else if (dev->speed > 100) {
391 unsigned long scl;
392
393 /* Fast mode */
394 scl = internal_clk / dev->speed;
395 fsscll = scl - (scl / 3) - 7;
396 fssclh = (scl / 3) - 5;
397 } else {
398 /* Standard mode */
399 fsscll = internal_clk / (dev->speed * 2) - 7;
400 fssclh = internal_clk / (dev->speed * 2) - 5;
401 }
402 scll = (hsscll << OMAP_I2C_SCLL_HSSCLL) | fsscll;
403 sclh = (hssclh << OMAP_I2C_SCLH_HSSCLH) | fssclh;
404 } else {
405 /* Program desired operating rate */
406 fclk_rate /= (psc + 1) * 1000;
407 if (psc > 2)
408 psc = 2;
409 scll = fclk_rate / (dev->speed * 2) - 7 + psc;
410 sclh = fclk_rate / (dev->speed * 2) - 7 + psc;
411 }
412
413 /* Setup clock prescaler to obtain approx 12MHz I2C module clock: */
414 omap_i2c_write_reg(dev, OMAP_I2C_PSC_REG, psc);
415
416 /* SCL low and high time values */
417 omap_i2c_write_reg(dev, OMAP_I2C_SCLL_REG, scll);
418 omap_i2c_write_reg(dev, OMAP_I2C_SCLH_REG, sclh);
419
420 if (dev->fifo_size) {
421 /* Note: setup required fifo size - 1. RTRSH and XTRSH */
422 buf = (dev->fifo_size - 1) << 8 | OMAP_I2C_BUF_RXFIF_CLR |
423 (dev->fifo_size - 1) | OMAP_I2C_BUF_TXFIF_CLR;
424 omap_i2c_write_reg(dev, OMAP_I2C_BUF_REG, buf);
425 }
426
427 /* Take the I2C module out of reset: */
428 omap_i2c_write_reg(dev, OMAP_I2C_CON_REG, OMAP_I2C_CON_EN);
429
430 /* Enable interrupts */
431 dev->iestate = (OMAP_I2C_IE_XRDY | OMAP_I2C_IE_RRDY |
432 OMAP_I2C_IE_ARDY | OMAP_I2C_IE_NACK |
433 OMAP_I2C_IE_AL) | ((dev->fifo_size) ?
434 (OMAP_I2C_IE_RDR | OMAP_I2C_IE_XDR) : 0);
435 omap_i2c_write_reg(dev, OMAP_I2C_IE_REG, dev->iestate);
436 if (dev->flags & OMAP_I2C_FLAG_RESET_REGS_POSTIDLE) {
437 dev->pscstate = psc;
438 dev->scllstate = scll;
439 dev->sclhstate = sclh;
440 dev->bufstate = buf;
441 }
442 return 0;
443 }
444
445 /*
446 * Waiting on Bus Busy
447 */
448 static int omap_i2c_wait_for_bb(struct omap_i2c_dev *dev)
449 {
450 unsigned long timeout;
451
452 timeout = jiffies + OMAP_I2C_TIMEOUT;
453 while (omap_i2c_read_reg(dev, OMAP_I2C_STAT_REG) & OMAP_I2C_STAT_BB) {
454 if (time_after(jiffies, timeout)) {
455 dev_warn(dev->dev, "timeout waiting for bus ready\n");
456 return -ETIMEDOUT;
457 }
458 msleep(1);
459 }
460
461 return 0;
462 }
463
464 /*
465 * Low level master read/write transaction.
466 */
467 static int omap_i2c_xfer_msg(struct i2c_adapter *adap,
468 struct i2c_msg *msg, int stop)
469 {
470 struct omap_i2c_dev *dev = i2c_get_adapdata(adap);
471 unsigned long timeout;
472 u16 w;
473
474 dev_dbg(dev->dev, "addr: 0x%04x, len: %d, flags: 0x%x, stop: %d\n",
475 msg->addr, msg->len, msg->flags, stop);
476
477 if (msg->len == 0)
478 return -EINVAL;
479
480 omap_i2c_write_reg(dev, OMAP_I2C_SA_REG, msg->addr);
481
482 /* REVISIT: Could the STB bit of I2C_CON be used with probing? */
483 dev->buf = msg->buf;
484 dev->buf_len = msg->len;
485
486 omap_i2c_write_reg(dev, OMAP_I2C_CNT_REG, dev->buf_len);
487
488 /* Clear the FIFO Buffers */
489 w = omap_i2c_read_reg(dev, OMAP_I2C_BUF_REG);
490 w |= OMAP_I2C_BUF_RXFIF_CLR | OMAP_I2C_BUF_TXFIF_CLR;
491 omap_i2c_write_reg(dev, OMAP_I2C_BUF_REG, w);
492
493 INIT_COMPLETION(dev->cmd_complete);
494 dev->cmd_err = 0;
495
496 w = OMAP_I2C_CON_EN | OMAP_I2C_CON_MST | OMAP_I2C_CON_STT;
497
498 /* High speed configuration */
499 if (dev->speed > 400)
500 w |= OMAP_I2C_CON_OPMODE_HS;
501
502 if (msg->flags & I2C_M_STOP)
503 stop = 1;
504 if (msg->flags & I2C_M_TEN)
505 w |= OMAP_I2C_CON_XA;
506 if (!(msg->flags & I2C_M_RD))
507 w |= OMAP_I2C_CON_TRX;
508
509 if (!dev->b_hw && stop)
510 w |= OMAP_I2C_CON_STP;
511
512 omap_i2c_write_reg(dev, OMAP_I2C_CON_REG, w);
513
514 /*
515 * Don't write stt and stp together on some hardware.
516 */
517 if (dev->b_hw && stop) {
518 unsigned long delay = jiffies + OMAP_I2C_TIMEOUT;
519 u16 con = omap_i2c_read_reg(dev, OMAP_I2C_CON_REG);
520 while (con & OMAP_I2C_CON_STT) {
521 con = omap_i2c_read_reg(dev, OMAP_I2C_CON_REG);
522
523 /* Let the user know if i2c is in a bad state */
524 if (time_after(jiffies, delay)) {
525 dev_err(dev->dev, "controller timed out "
526 "waiting for start condition to finish\n");
527 return -ETIMEDOUT;
528 }
529 cpu_relax();
530 }
531
532 w |= OMAP_I2C_CON_STP;
533 w &= ~OMAP_I2C_CON_STT;
534 omap_i2c_write_reg(dev, OMAP_I2C_CON_REG, w);
535 }
536
537 /*
538 * REVISIT: We should abort the transfer on signals, but the bus goes
539 * into arbitration and we're currently unable to recover from it.
540 */
541 timeout = wait_for_completion_timeout(&dev->cmd_complete,
542 OMAP_I2C_TIMEOUT);
543 dev->buf_len = 0;
544 if (timeout == 0) {
545 dev_err(dev->dev, "controller timed out\n");
546 omap_i2c_init(dev);
547 return -ETIMEDOUT;
548 }
549
550 if (likely(!dev->cmd_err))
551 return 0;
552
553 /* We have an error */
554 if (dev->cmd_err & (OMAP_I2C_STAT_AL | OMAP_I2C_STAT_ROVR |
555 OMAP_I2C_STAT_XUDF)) {
556 omap_i2c_init(dev);
557 return -EIO;
558 }
559
560 if (dev->cmd_err & OMAP_I2C_STAT_NACK) {
561 if (msg->flags & I2C_M_IGNORE_NAK)
562 return 0;
563 if (stop) {
564 w = omap_i2c_read_reg(dev, OMAP_I2C_CON_REG);
565 w |= OMAP_I2C_CON_STP;
566 omap_i2c_write_reg(dev, OMAP_I2C_CON_REG, w);
567 }
568 return -EREMOTEIO;
569 }
570 return -EIO;
571 }
572
573
574 /*
575 * Prepare controller for a transaction and call omap_i2c_xfer_msg
576 * to do the work during IRQ processing.
577 */
578 static int
579 omap_i2c_xfer(struct i2c_adapter *adap, struct i2c_msg msgs[], int num)
580 {
581 struct omap_i2c_dev *dev = i2c_get_adapdata(adap);
582 int i;
583 int r;
584
585 r = pm_runtime_get_sync(dev->dev);
586 if (IS_ERR_VALUE(r))
587 goto out;
588
589 r = omap_i2c_wait_for_bb(dev);
590 if (r < 0)
591 goto out;
592
593 if (dev->set_mpu_wkup_lat != NULL)
594 dev->set_mpu_wkup_lat(dev->dev, dev->latency);
595
596 for (i = 0; i < num; i++) {
597 r = omap_i2c_xfer_msg(adap, &msgs[i], (i == (num - 1)));
598 if (r != 0)
599 break;
600 }
601
602 if (dev->set_mpu_wkup_lat != NULL)
603 dev->set_mpu_wkup_lat(dev->dev, -1);
604
605 if (r == 0)
606 r = num;
607
608 omap_i2c_wait_for_bb(dev);
609 out:
610 pm_runtime_put(dev->dev);
611 return r;
612 }
613
614 static u32
615 omap_i2c_func(struct i2c_adapter *adap)
616 {
617 return I2C_FUNC_I2C | (I2C_FUNC_SMBUS_EMUL & ~I2C_FUNC_SMBUS_QUICK) |
618 I2C_FUNC_PROTOCOL_MANGLING;
619 }
620
621 static inline void
622 omap_i2c_complete_cmd(struct omap_i2c_dev *dev, u16 err)
623 {
624 dev->cmd_err |= err;
625 complete(&dev->cmd_complete);
626 }
627
628 static inline void
629 omap_i2c_ack_stat(struct omap_i2c_dev *dev, u16 stat)
630 {
631 omap_i2c_write_reg(dev, OMAP_I2C_STAT_REG, stat);
632 }
633
634 static inline void i2c_omap_errata_i207(struct omap_i2c_dev *dev, u16 stat)
635 {
636 /*
637 * I2C Errata(Errata Nos. OMAP2: 1.67, OMAP3: 1.8)
638 * Not applicable for OMAP4.
639 * Under certain rare conditions, RDR could be set again
640 * when the bus is busy, then ignore the interrupt and
641 * clear the interrupt.
642 */
643 if (stat & OMAP_I2C_STAT_RDR) {
644 /* Step 1: If RDR is set, clear it */
645 omap_i2c_ack_stat(dev, OMAP_I2C_STAT_RDR);
646
647 /* Step 2: */
648 if (!(omap_i2c_read_reg(dev, OMAP_I2C_STAT_REG)
649 & OMAP_I2C_STAT_BB)) {
650
651 /* Step 3: */
652 if (omap_i2c_read_reg(dev, OMAP_I2C_STAT_REG)
653 & OMAP_I2C_STAT_RDR) {
654 omap_i2c_ack_stat(dev, OMAP_I2C_STAT_RDR);
655 dev_dbg(dev->dev, "RDR when bus is busy.\n");
656 }
657
658 }
659 }
660 }
661
662 /* rev1 devices are apparently only on some 15xx */
663 #ifdef CONFIG_ARCH_OMAP15XX
664
665 static irqreturn_t
666 omap_i2c_omap1_isr(int this_irq, void *dev_id)
667 {
668 struct omap_i2c_dev *dev = dev_id;
669 u16 iv, w;
670
671 if (pm_runtime_suspended(dev->dev))
672 return IRQ_NONE;
673
674 iv = omap_i2c_read_reg(dev, OMAP_I2C_IV_REG);
675 switch (iv) {
676 case 0x00: /* None */
677 break;
678 case 0x01: /* Arbitration lost */
679 dev_err(dev->dev, "Arbitration lost\n");
680 omap_i2c_complete_cmd(dev, OMAP_I2C_STAT_AL);
681 break;
682 case 0x02: /* No acknowledgement */
683 omap_i2c_complete_cmd(dev, OMAP_I2C_STAT_NACK);
684 omap_i2c_write_reg(dev, OMAP_I2C_CON_REG, OMAP_I2C_CON_STP);
685 break;
686 case 0x03: /* Register access ready */
687 omap_i2c_complete_cmd(dev, 0);
688 break;
689 case 0x04: /* Receive data ready */
690 if (dev->buf_len) {
691 w = omap_i2c_read_reg(dev, OMAP_I2C_DATA_REG);
692 *dev->buf++ = w;
693 dev->buf_len--;
694 if (dev->buf_len) {
695 *dev->buf++ = w >> 8;
696 dev->buf_len--;
697 }
698 } else
699 dev_err(dev->dev, "RRDY IRQ while no data requested\n");
700 break;
701 case 0x05: /* Transmit data ready */
702 if (dev->buf_len) {
703 w = *dev->buf++;
704 dev->buf_len--;
705 if (dev->buf_len) {
706 w |= *dev->buf++ << 8;
707 dev->buf_len--;
708 }
709 omap_i2c_write_reg(dev, OMAP_I2C_DATA_REG, w);
710 } else
711 dev_err(dev->dev, "XRDY IRQ while no data to send\n");
712 break;
713 default:
714 return IRQ_NONE;
715 }
716
717 return IRQ_HANDLED;
718 }
719 #else
720 #define omap_i2c_omap1_isr NULL
721 #endif
722
723 /*
724 * OMAP3430 Errata i462: When an XRDY/XDR is hit, wait for XUDF before writing
725 * data to DATA_REG. Otherwise some data bytes can be lost while transferring
726 * them from the memory to the I2C interface.
727 */
728 static int errata_omap3_i462(struct omap_i2c_dev *dev, u16 *stat, int *err)
729 {
730 unsigned long timeout = 10000;
731
732 while (--timeout && !(*stat & OMAP_I2C_STAT_XUDF)) {
733 if (*stat & (OMAP_I2C_STAT_NACK | OMAP_I2C_STAT_AL)) {
734 omap_i2c_ack_stat(dev, (OMAP_I2C_STAT_XRDY |
735 OMAP_I2C_STAT_XDR));
736 return -ETIMEDOUT;
737 }
738
739 cpu_relax();
740 *stat = omap_i2c_read_reg(dev, OMAP_I2C_STAT_REG);
741 }
742
743 if (!timeout) {
744 dev_err(dev->dev, "timeout waiting on XUDF bit\n");
745 return 0;
746 }
747
748 *err |= OMAP_I2C_STAT_XUDF;
749 return 0;
750 }
751
752 static irqreturn_t
753 omap_i2c_isr(int this_irq, void *dev_id)
754 {
755 struct omap_i2c_dev *dev = dev_id;
756 u16 bits;
757 u16 stat, w;
758 int err, count = 0;
759
760 if (pm_runtime_suspended(dev->dev))
761 return IRQ_NONE;
762
763 bits = omap_i2c_read_reg(dev, OMAP_I2C_IE_REG);
764 while ((stat = (omap_i2c_read_reg(dev, OMAP_I2C_STAT_REG))) & bits) {
765 dev_dbg(dev->dev, "IRQ (ISR = 0x%04x)\n", stat);
766 if (count++ == 100) {
767 dev_warn(dev->dev, "Too much work in one IRQ\n");
768 break;
769 }
770
771 err = 0;
772 complete:
773 /*
774 * Ack the stat in one go, but [R/X]DR and [R/X]RDY should be
775 * acked after the data operation is complete.
776 * Ref: TRM SWPU114Q Figure 18-31
777 */
778 omap_i2c_write_reg(dev, OMAP_I2C_STAT_REG, stat &
779 ~(OMAP_I2C_STAT_RRDY | OMAP_I2C_STAT_RDR |
780 OMAP_I2C_STAT_XRDY | OMAP_I2C_STAT_XDR));
781
782 if (stat & OMAP_I2C_STAT_NACK)
783 err |= OMAP_I2C_STAT_NACK;
784
785 if (stat & OMAP_I2C_STAT_AL) {
786 dev_err(dev->dev, "Arbitration lost\n");
787 err |= OMAP_I2C_STAT_AL;
788 }
789
790 /*
791 * ProDB0017052: Clear ARDY bit twice
792 */
793 if (stat & (OMAP_I2C_STAT_ARDY | OMAP_I2C_STAT_NACK |
794 OMAP_I2C_STAT_AL)) {
795 omap_i2c_ack_stat(dev, (OMAP_I2C_STAT_RRDY |
796 OMAP_I2C_STAT_RDR |
797 OMAP_I2C_STAT_XRDY |
798 OMAP_I2C_STAT_XDR |
799 OMAP_I2C_STAT_ARDY));
800 omap_i2c_complete_cmd(dev, err);
801 return IRQ_HANDLED;
802 }
803
804 if (stat & (OMAP_I2C_STAT_RRDY | OMAP_I2C_STAT_RDR)) {
805 u8 num_bytes = 1;
806
807 if (dev->errata & I2C_OMAP_ERRATA_I207)
808 i2c_omap_errata_i207(dev, stat);
809
810 if (dev->fifo_size) {
811 if (stat & OMAP_I2C_STAT_RRDY)
812 num_bytes = dev->fifo_size;
813 else /* read RXSTAT on RDR interrupt */
814 num_bytes = (omap_i2c_read_reg(dev,
815 OMAP_I2C_BUFSTAT_REG)
816 >> 8) & 0x3F;
817 }
818 while (num_bytes--) {
819 if (!dev->buf_len) {
820 if (stat & OMAP_I2C_STAT_RRDY)
821 dev_err(dev->dev,
822 "RRDY IRQ while no data"
823 " requested\n");
824 if (stat & OMAP_I2C_STAT_RDR)
825 dev_err(dev->dev,
826 "RDR IRQ while no data"
827 " requested\n");
828 break;
829 }
830
831 w = omap_i2c_read_reg(dev, OMAP_I2C_DATA_REG);
832 *dev->buf++ = w;
833 dev->buf_len--;
834 /*
835 * Data reg in 2430, omap3 and
836 * omap4 is 8 bit wide
837 */
838 if (dev->flags &
839 OMAP_I2C_FLAG_16BIT_DATA_REG) {
840 if (dev->buf_len) {
841 *dev->buf++ = w >> 8;
842 dev->buf_len--;
843 }
844 }
845 }
846 omap_i2c_ack_stat(dev, (OMAP_I2C_STAT_RRDY |
847 OMAP_I2C_STAT_RDR));
848 continue;
849 }
850
851 if (stat & (OMAP_I2C_STAT_XRDY | OMAP_I2C_STAT_XDR)) {
852 u8 num_bytes = 1;
853 if (dev->fifo_size) {
854 if (stat & OMAP_I2C_STAT_XRDY)
855 num_bytes = dev->fifo_size;
856 else /* read TXSTAT on XDR interrupt */
857 num_bytes = omap_i2c_read_reg(dev,
858 OMAP_I2C_BUFSTAT_REG)
859 & 0x3F;
860 }
861 while (num_bytes--) {
862 if (!dev->buf_len) {
863 if (stat & OMAP_I2C_STAT_XRDY)
864 dev_err(dev->dev,
865 "XRDY IRQ while no "
866 "data to send\n");
867 if (stat & OMAP_I2C_STAT_XDR)
868 dev_err(dev->dev,
869 "XDR IRQ while no "
870 "data to send\n");
871 break;
872 }
873
874 w = *dev->buf++;
875 dev->buf_len--;
876 /*
877 * Data reg in 2430, omap3 and
878 * omap4 is 8 bit wide
879 */
880 if (dev->flags &
881 OMAP_I2C_FLAG_16BIT_DATA_REG) {
882 if (dev->buf_len) {
883 w |= *dev->buf++ << 8;
884 dev->buf_len--;
885 }
886 }
887
888 if ((dev->errata & I2C_OMAP_ERRATA_I462) &&
889 errata_omap3_i462(dev, &stat, &err))
890 goto complete;
891
892 omap_i2c_write_reg(dev, OMAP_I2C_DATA_REG, w);
893 }
894 omap_i2c_ack_stat(dev, (OMAP_I2C_STAT_XRDY |
895 OMAP_I2C_STAT_XDR));
896 continue;
897 }
898
899 if (stat & OMAP_I2C_STAT_ROVR) {
900 dev_err(dev->dev, "Receive overrun\n");
901 dev->cmd_err |= OMAP_I2C_STAT_ROVR;
902 }
903
904 if (stat & OMAP_I2C_STAT_XUDF) {
905 dev_err(dev->dev, "Transmit underflow\n");
906 dev->cmd_err |= OMAP_I2C_STAT_XUDF;
907 }
908 }
909
910 return count ? IRQ_HANDLED : IRQ_NONE;
911 }
912
913 static const struct i2c_algorithm omap_i2c_algo = {
914 .master_xfer = omap_i2c_xfer,
915 .functionality = omap_i2c_func,
916 };
917
918 #ifdef CONFIG_OF
919 static struct omap_i2c_bus_platform_data omap3_pdata = {
920 .rev = OMAP_I2C_IP_VERSION_1,
921 .flags = OMAP_I2C_FLAG_APPLY_ERRATA_I207 |
922 OMAP_I2C_FLAG_RESET_REGS_POSTIDLE |
923 OMAP_I2C_FLAG_BUS_SHIFT_2,
924 };
925
926 static struct omap_i2c_bus_platform_data omap4_pdata = {
927 .rev = OMAP_I2C_IP_VERSION_2,
928 };
929
930 static const struct of_device_id omap_i2c_of_match[] = {
931 {
932 .compatible = "ti,omap4-i2c",
933 .data = &omap4_pdata,
934 },
935 {
936 .compatible = "ti,omap3-i2c",
937 .data = &omap3_pdata,
938 },
939 { },
940 };
941 MODULE_DEVICE_TABLE(of, omap_i2c_of_match);
942 #endif
943
944 static int __devinit
945 omap_i2c_probe(struct platform_device *pdev)
946 {
947 struct omap_i2c_dev *dev;
948 struct i2c_adapter *adap;
949 struct resource *mem, *irq;
950 struct omap_i2c_bus_platform_data *pdata = pdev->dev.platform_data;
951 struct device_node *node = pdev->dev.of_node;
952 const struct of_device_id *match;
953 irq_handler_t isr;
954 int r;
955
956 /* NOTE: driver uses the static register mapping */
957 mem = platform_get_resource(pdev, IORESOURCE_MEM, 0);
958 if (!mem) {
959 dev_err(&pdev->dev, "no mem resource?\n");
960 return -ENODEV;
961 }
962 irq = platform_get_resource(pdev, IORESOURCE_IRQ, 0);
963 if (!irq) {
964 dev_err(&pdev->dev, "no irq resource?\n");
965 return -ENODEV;
966 }
967
968 dev = devm_kzalloc(&pdev->dev, sizeof(struct omap_i2c_dev), GFP_KERNEL);
969 if (!dev) {
970 dev_err(&pdev->dev, "Menory allocation failed\n");
971 return -ENOMEM;
972 }
973
974 dev->base = devm_request_and_ioremap(&pdev->dev, mem);
975 if (!dev->base) {
976 dev_err(&pdev->dev, "I2C region already claimed\n");
977 return -ENOMEM;
978 }
979
980 match = of_match_device(of_match_ptr(omap_i2c_of_match), &pdev->dev);
981 if (match) {
982 u32 freq = 100000; /* default to 100000 Hz */
983
984 pdata = match->data;
985 dev->dtrev = pdata->rev;
986 dev->flags = pdata->flags;
987
988 of_property_read_u32(node, "clock-frequency", &freq);
989 /* convert DT freq value in Hz into kHz for speed */
990 dev->speed = freq / 1000;
991 } else if (pdata != NULL) {
992 dev->speed = pdata->clkrate;
993 dev->flags = pdata->flags;
994 dev->set_mpu_wkup_lat = pdata->set_mpu_wkup_lat;
995 dev->dtrev = pdata->rev;
996 }
997
998 dev->dev = &pdev->dev;
999 dev->irq = irq->start;
1000
1001 platform_set_drvdata(pdev, dev);
1002 init_completion(&dev->cmd_complete);
1003
1004 dev->reg_shift = (dev->flags >> OMAP_I2C_FLAG_BUS_SHIFT__SHIFT) & 3;
1005
1006 if (dev->dtrev == OMAP_I2C_IP_VERSION_2)
1007 dev->regs = (u8 *)reg_map_ip_v2;
1008 else
1009 dev->regs = (u8 *)reg_map_ip_v1;
1010
1011 pm_runtime_enable(dev->dev);
1012 r = pm_runtime_get_sync(dev->dev);
1013 if (IS_ERR_VALUE(r))
1014 goto err_free_mem;
1015
1016 dev->rev = omap_i2c_read_reg(dev, OMAP_I2C_REV_REG) & 0xff;
1017
1018 dev->errata = 0;
1019
1020 if (dev->flags & OMAP_I2C_FLAG_APPLY_ERRATA_I207)
1021 dev->errata |= I2C_OMAP_ERRATA_I207;
1022
1023 if (dev->rev <= OMAP_I2C_REV_ON_3430_3530)
1024 dev->errata |= I2C_OMAP_ERRATA_I462;
1025
1026 if (!(dev->flags & OMAP_I2C_FLAG_NO_FIFO)) {
1027 u16 s;
1028
1029 /* Set up the fifo size - Get total size */
1030 s = (omap_i2c_read_reg(dev, OMAP_I2C_BUFSTAT_REG) >> 14) & 0x3;
1031 dev->fifo_size = 0x8 << s;
1032
1033 /*
1034 * Set up notification threshold as half the total available
1035 * size. This is to ensure that we can handle the status on int
1036 * call back latencies.
1037 */
1038
1039 dev->fifo_size = (dev->fifo_size / 2);
1040
1041 if (dev->rev >= OMAP_I2C_REV_ON_3630_4430)
1042 dev->b_hw = 0; /* Disable hardware fixes */
1043 else
1044 dev->b_hw = 1; /* Enable hardware fixes */
1045
1046 /* calculate wakeup latency constraint for MPU */
1047 if (dev->set_mpu_wkup_lat != NULL)
1048 dev->latency = (1000000 * dev->fifo_size) /
1049 (1000 * dev->speed / 8);
1050 }
1051
1052 /* reset ASAP, clearing any IRQs */
1053 omap_i2c_init(dev);
1054
1055 isr = (dev->rev < OMAP_I2C_OMAP1_REV_2) ? omap_i2c_omap1_isr :
1056 omap_i2c_isr;
1057 r = devm_request_irq(&pdev->dev, dev->irq, isr, IRQF_NO_SUSPEND,
1058 pdev->name, dev);
1059
1060 if (r) {
1061 dev_err(dev->dev, "failure requesting irq %i\n", dev->irq);
1062 goto err_unuse_clocks;
1063 }
1064
1065 dev_info(dev->dev, "bus %d rev%d.%d.%d at %d kHz\n", pdev->id,
1066 dev->dtrev, dev->rev >> 4, dev->rev & 0xf, dev->speed);
1067
1068 adap = &dev->adapter;
1069 i2c_set_adapdata(adap, dev);
1070 adap->owner = THIS_MODULE;
1071 adap->class = I2C_CLASS_HWMON;
1072 strlcpy(adap->name, "OMAP I2C adapter", sizeof(adap->name));
1073 adap->algo = &omap_i2c_algo;
1074 adap->dev.parent = &pdev->dev;
1075 adap->dev.of_node = pdev->dev.of_node;
1076
1077 /* i2c device drivers may be active on return from add_adapter() */
1078 adap->nr = pdev->id;
1079 r = i2c_add_numbered_adapter(adap);
1080 if (r) {
1081 dev_err(dev->dev, "failure adding adapter\n");
1082 goto err_unuse_clocks;
1083 }
1084
1085 of_i2c_register_devices(adap);
1086
1087 pm_runtime_put(dev->dev);
1088
1089 return 0;
1090
1091 err_unuse_clocks:
1092 omap_i2c_write_reg(dev, OMAP_I2C_CON_REG, 0);
1093 pm_runtime_put(dev->dev);
1094 pm_runtime_disable(&pdev->dev);
1095 err_free_mem:
1096 platform_set_drvdata(pdev, NULL);
1097
1098 return r;
1099 }
1100
1101 static int __devexit omap_i2c_remove(struct platform_device *pdev)
1102 {
1103 struct omap_i2c_dev *dev = platform_get_drvdata(pdev);
1104 int ret;
1105
1106 platform_set_drvdata(pdev, NULL);
1107
1108 i2c_del_adapter(&dev->adapter);
1109 ret = pm_runtime_get_sync(&pdev->dev);
1110 if (IS_ERR_VALUE(ret))
1111 return ret;
1112
1113 omap_i2c_write_reg(dev, OMAP_I2C_CON_REG, 0);
1114 pm_runtime_put(&pdev->dev);
1115 pm_runtime_disable(&pdev->dev);
1116 return 0;
1117 }
1118
1119 #ifdef CONFIG_PM
1120 #ifdef CONFIG_PM_RUNTIME
1121 static int omap_i2c_runtime_suspend(struct device *dev)
1122 {
1123 struct platform_device *pdev = to_platform_device(dev);
1124 struct omap_i2c_dev *_dev = platform_get_drvdata(pdev);
1125 u16 iv;
1126
1127 _dev->iestate = omap_i2c_read_reg(_dev, OMAP_I2C_IE_REG);
1128
1129 omap_i2c_write_reg(_dev, OMAP_I2C_IE_REG, 0);
1130
1131 if (_dev->rev < OMAP_I2C_OMAP1_REV_2) {
1132 iv = omap_i2c_read_reg(_dev, OMAP_I2C_IV_REG); /* Read clears */
1133 } else {
1134 omap_i2c_write_reg(_dev, OMAP_I2C_STAT_REG, _dev->iestate);
1135
1136 /* Flush posted write */
1137 omap_i2c_read_reg(_dev, OMAP_I2C_STAT_REG);
1138 }
1139
1140 return 0;
1141 }
1142
1143 static int omap_i2c_runtime_resume(struct device *dev)
1144 {
1145 struct platform_device *pdev = to_platform_device(dev);
1146 struct omap_i2c_dev *_dev = platform_get_drvdata(pdev);
1147
1148 if (_dev->flags & OMAP_I2C_FLAG_RESET_REGS_POSTIDLE) {
1149 omap_i2c_write_reg(_dev, OMAP_I2C_CON_REG, 0);
1150 omap_i2c_write_reg(_dev, OMAP_I2C_PSC_REG, _dev->pscstate);
1151 omap_i2c_write_reg(_dev, OMAP_I2C_SCLL_REG, _dev->scllstate);
1152 omap_i2c_write_reg(_dev, OMAP_I2C_SCLH_REG, _dev->sclhstate);
1153 omap_i2c_write_reg(_dev, OMAP_I2C_BUF_REG, _dev->bufstate);
1154 omap_i2c_write_reg(_dev, OMAP_I2C_SYSC_REG, _dev->syscstate);
1155 omap_i2c_write_reg(_dev, OMAP_I2C_WE_REG, _dev->westate);
1156 omap_i2c_write_reg(_dev, OMAP_I2C_CON_REG, OMAP_I2C_CON_EN);
1157 }
1158
1159 /*
1160 * Don't write to this register if the IE state is 0 as it can
1161 * cause deadlock.
1162 */
1163 if (_dev->iestate)
1164 omap_i2c_write_reg(_dev, OMAP_I2C_IE_REG, _dev->iestate);
1165
1166 return 0;
1167 }
1168 #endif /* CONFIG_PM_RUNTIME */
1169
1170 static struct dev_pm_ops omap_i2c_pm_ops = {
1171 SET_RUNTIME_PM_OPS(omap_i2c_runtime_suspend,
1172 omap_i2c_runtime_resume, NULL)
1173 };
1174 #define OMAP_I2C_PM_OPS (&omap_i2c_pm_ops)
1175 #else
1176 #define OMAP_I2C_PM_OPS NULL
1177 #endif /* CONFIG_PM */
1178
1179 static struct platform_driver omap_i2c_driver = {
1180 .probe = omap_i2c_probe,
1181 .remove = __devexit_p(omap_i2c_remove),
1182 .driver = {
1183 .name = "omap_i2c",
1184 .owner = THIS_MODULE,
1185 .pm = OMAP_I2C_PM_OPS,
1186 .of_match_table = of_match_ptr(omap_i2c_of_match),
1187 },
1188 };
1189
1190 /* I2C may be needed to bring up other drivers */
1191 static int __init
1192 omap_i2c_init_driver(void)
1193 {
1194 return platform_driver_register(&omap_i2c_driver);
1195 }
1196 subsys_initcall(omap_i2c_init_driver);
1197
1198 static void __exit omap_i2c_exit_driver(void)
1199 {
1200 platform_driver_unregister(&omap_i2c_driver);
1201 }
1202 module_exit(omap_i2c_exit_driver);
1203
1204 MODULE_AUTHOR("MontaVista Software, Inc. (and others)");
1205 MODULE_DESCRIPTION("TI OMAP I2C bus adapter");
1206 MODULE_LICENSE("GPL");
1207 MODULE_ALIAS("platform:omap_i2c");
Linus' kernel tree