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 #include <linux/pinctrl/consumer.h>
47
48 /* I2C controller revisions */
49 #define OMAP_I2C_OMAP1_REV_2 0x20
50
51 /* I2C controller revisions present on specific hardware */
52 #define OMAP_I2C_REV_ON_2430 0x00000036
53 #define OMAP_I2C_REV_ON_3430_3530 0x0000003C
54 #define OMAP_I2C_REV_ON_3630 0x00000040
55 #define OMAP_I2C_REV_ON_4430_PLUS 0x50400002
56
57 /* timeout waiting for the controller to respond */
58 #define OMAP_I2C_TIMEOUT (msecs_to_jiffies(1000))
59
60 /* timeout for pm runtime autosuspend */
61 #define OMAP_I2C_PM_TIMEOUT 1000 /* ms */
62
63 /* For OMAP3 I2C_IV has changed to I2C_WE (wakeup enable) */
64 enum {
65 OMAP_I2C_REV_REG = 0,
66 OMAP_I2C_IE_REG,
67 OMAP_I2C_STAT_REG,
68 OMAP_I2C_IV_REG,
69 OMAP_I2C_WE_REG,
70 OMAP_I2C_SYSS_REG,
71 OMAP_I2C_BUF_REG,
72 OMAP_I2C_CNT_REG,
73 OMAP_I2C_DATA_REG,
74 OMAP_I2C_SYSC_REG,
75 OMAP_I2C_CON_REG,
76 OMAP_I2C_OA_REG,
77 OMAP_I2C_SA_REG,
78 OMAP_I2C_PSC_REG,
79 OMAP_I2C_SCLL_REG,
80 OMAP_I2C_SCLH_REG,
81 OMAP_I2C_SYSTEST_REG,
82 OMAP_I2C_BUFSTAT_REG,
83 /* only on OMAP4430 */
84 OMAP_I2C_IP_V2_REVNB_LO,
85 OMAP_I2C_IP_V2_REVNB_HI,
86 OMAP_I2C_IP_V2_IRQSTATUS_RAW,
87 OMAP_I2C_IP_V2_IRQENABLE_SET,
88 OMAP_I2C_IP_V2_IRQENABLE_CLR,
89 };
90
91 /* I2C Interrupt Enable Register (OMAP_I2C_IE): */
92 #define OMAP_I2C_IE_XDR (1 << 14) /* TX Buffer drain int enable */
93 #define OMAP_I2C_IE_RDR (1 << 13) /* RX Buffer drain int enable */
94 #define OMAP_I2C_IE_XRDY (1 << 4) /* TX data ready int enable */
95 #define OMAP_I2C_IE_RRDY (1 << 3) /* RX data ready int enable */
96 #define OMAP_I2C_IE_ARDY (1 << 2) /* Access ready int enable */
97 #define OMAP_I2C_IE_NACK (1 << 1) /* No ack interrupt enable */
98 #define OMAP_I2C_IE_AL (1 << 0) /* Arbitration lost int ena */
99
100 /* I2C Status Register (OMAP_I2C_STAT): */
101 #define OMAP_I2C_STAT_XDR (1 << 14) /* TX Buffer draining */
102 #define OMAP_I2C_STAT_RDR (1 << 13) /* RX Buffer draining */
103 #define OMAP_I2C_STAT_BB (1 << 12) /* Bus busy */
104 #define OMAP_I2C_STAT_ROVR (1 << 11) /* Receive overrun */
105 #define OMAP_I2C_STAT_XUDF (1 << 10) /* Transmit underflow */
106 #define OMAP_I2C_STAT_AAS (1 << 9) /* Address as slave */
107 #define OMAP_I2C_STAT_AD0 (1 << 8) /* Address zero */
108 #define OMAP_I2C_STAT_XRDY (1 << 4) /* Transmit data ready */
109 #define OMAP_I2C_STAT_RRDY (1 << 3) /* Receive data ready */
110 #define OMAP_I2C_STAT_ARDY (1 << 2) /* Register access ready */
111 #define OMAP_I2C_STAT_NACK (1 << 1) /* No ack interrupt enable */
112 #define OMAP_I2C_STAT_AL (1 << 0) /* Arbitration lost int ena */
113
114 /* I2C WE wakeup enable register */
115 #define OMAP_I2C_WE_XDR_WE (1 << 14) /* TX drain wakup */
116 #define OMAP_I2C_WE_RDR_WE (1 << 13) /* RX drain wakeup */
117 #define OMAP_I2C_WE_AAS_WE (1 << 9) /* Address as slave wakeup*/
118 #define OMAP_I2C_WE_BF_WE (1 << 8) /* Bus free wakeup */
119 #define OMAP_I2C_WE_STC_WE (1 << 6) /* Start condition wakeup */
120 #define OMAP_I2C_WE_GC_WE (1 << 5) /* General call wakeup */
121 #define OMAP_I2C_WE_DRDY_WE (1 << 3) /* TX/RX data ready wakeup */
122 #define OMAP_I2C_WE_ARDY_WE (1 << 2) /* Reg access ready wakeup */
123 #define OMAP_I2C_WE_NACK_WE (1 << 1) /* No acknowledgment wakeup */
124 #define OMAP_I2C_WE_AL_WE (1 << 0) /* Arbitration lost wakeup */
125
126 #define OMAP_I2C_WE_ALL (OMAP_I2C_WE_XDR_WE | OMAP_I2C_WE_RDR_WE | \
127 OMAP_I2C_WE_AAS_WE | OMAP_I2C_WE_BF_WE | \
128 OMAP_I2C_WE_STC_WE | OMAP_I2C_WE_GC_WE | \
129 OMAP_I2C_WE_DRDY_WE | OMAP_I2C_WE_ARDY_WE | \
130 OMAP_I2C_WE_NACK_WE | OMAP_I2C_WE_AL_WE)
131
132 /* I2C Buffer Configuration Register (OMAP_I2C_BUF): */
133 #define OMAP_I2C_BUF_RDMA_EN (1 << 15) /* RX DMA channel enable */
134 #define OMAP_I2C_BUF_RXFIF_CLR (1 << 14) /* RX FIFO Clear */
135 #define OMAP_I2C_BUF_XDMA_EN (1 << 7) /* TX DMA channel enable */
136 #define OMAP_I2C_BUF_TXFIF_CLR (1 << 6) /* TX FIFO Clear */
137
138 /* I2C Configuration Register (OMAP_I2C_CON): */
139 #define OMAP_I2C_CON_EN (1 << 15) /* I2C module enable */
140 #define OMAP_I2C_CON_BE (1 << 14) /* Big endian mode */
141 #define OMAP_I2C_CON_OPMODE_HS (1 << 12) /* High Speed support */
142 #define OMAP_I2C_CON_STB (1 << 11) /* Start byte mode (master) */
143 #define OMAP_I2C_CON_MST (1 << 10) /* Master/slave mode */
144 #define OMAP_I2C_CON_TRX (1 << 9) /* TX/RX mode (master only) */
145 #define OMAP_I2C_CON_XA (1 << 8) /* Expand address */
146 #define OMAP_I2C_CON_RM (1 << 2) /* Repeat mode (master only) */
147 #define OMAP_I2C_CON_STP (1 << 1) /* Stop cond (master only) */
148 #define OMAP_I2C_CON_STT (1 << 0) /* Start condition (master) */
149
150 /* I2C SCL time value when Master */
151 #define OMAP_I2C_SCLL_HSSCLL 8
152 #define OMAP_I2C_SCLH_HSSCLH 8
153
154 /* I2C System Test Register (OMAP_I2C_SYSTEST): */
155 #ifdef DEBUG
156 #define OMAP_I2C_SYSTEST_ST_EN (1 << 15) /* System test enable */
157 #define OMAP_I2C_SYSTEST_FREE (1 << 14) /* Free running mode */
158 #define OMAP_I2C_SYSTEST_TMODE_MASK (3 << 12) /* Test mode select */
159 #define OMAP_I2C_SYSTEST_TMODE_SHIFT (12) /* Test mode select */
160 #define OMAP_I2C_SYSTEST_SCL_I (1 << 3) /* SCL line sense in */
161 #define OMAP_I2C_SYSTEST_SCL_O (1 << 2) /* SCL line drive out */
162 #define OMAP_I2C_SYSTEST_SDA_I (1 << 1) /* SDA line sense in */
163 #define OMAP_I2C_SYSTEST_SDA_O (1 << 0) /* SDA line drive out */
164 #endif
165
166 /* OCP_SYSSTATUS bit definitions */
167 #define SYSS_RESETDONE_MASK (1 << 0)
168
169 /* OCP_SYSCONFIG bit definitions */
170 #define SYSC_CLOCKACTIVITY_MASK (0x3 << 8)
171 #define SYSC_SIDLEMODE_MASK (0x3 << 3)
172 #define SYSC_ENAWAKEUP_MASK (1 << 2)
173 #define SYSC_SOFTRESET_MASK (1 << 1)
174 #define SYSC_AUTOIDLE_MASK (1 << 0)
175
176 #define SYSC_IDLEMODE_SMART 0x2
177 #define SYSC_CLOCKACTIVITY_FCLK 0x2
178
179 /* Errata definitions */
180 #define I2C_OMAP_ERRATA_I207 (1 << 0)
181 #define I2C_OMAP_ERRATA_I462 (1 << 1)
182
183 struct omap_i2c_dev {
184 spinlock_t lock; /* IRQ synchronization */
185 struct device *dev;
186 void __iomem *base; /* virtual */
187 int irq;
188 int reg_shift; /* bit shift for I2C register addresses */
189 struct completion cmd_complete;
190 struct resource *ioarea;
191 u32 latency; /* maximum mpu wkup latency */
192 void (*set_mpu_wkup_lat)(struct device *dev,
193 long latency);
194 u32 speed; /* Speed of bus in kHz */
195 u32 flags;
196 u16 cmd_err;
197 u8 *buf;
198 u8 *regs;
199 size_t buf_len;
200 struct i2c_adapter adapter;
201 u8 threshold;
202 u8 fifo_size; /* use as flag and value
203 * fifo_size==0 implies no fifo
204 * if set, should be trsh+1
205 */
206 u32 rev;
207 unsigned b_hw:1; /* bad h/w fixes */
208 unsigned receiver:1; /* true when we're in receiver mode */
209 u16 iestate; /* Saved interrupt register */
210 u16 pscstate;
211 u16 scllstate;
212 u16 sclhstate;
213 u16 syscstate;
214 u16 westate;
215 u16 errata;
216
217 struct pinctrl *pins;
218 };
219
220 static const u8 reg_map_ip_v1[] = {
221 [OMAP_I2C_REV_REG] = 0x00,
222 [OMAP_I2C_IE_REG] = 0x01,
223 [OMAP_I2C_STAT_REG] = 0x02,
224 [OMAP_I2C_IV_REG] = 0x03,
225 [OMAP_I2C_WE_REG] = 0x03,
226 [OMAP_I2C_SYSS_REG] = 0x04,
227 [OMAP_I2C_BUF_REG] = 0x05,
228 [OMAP_I2C_CNT_REG] = 0x06,
229 [OMAP_I2C_DATA_REG] = 0x07,
230 [OMAP_I2C_SYSC_REG] = 0x08,
231 [OMAP_I2C_CON_REG] = 0x09,
232 [OMAP_I2C_OA_REG] = 0x0a,
233 [OMAP_I2C_SA_REG] = 0x0b,
234 [OMAP_I2C_PSC_REG] = 0x0c,
235 [OMAP_I2C_SCLL_REG] = 0x0d,
236 [OMAP_I2C_SCLH_REG] = 0x0e,
237 [OMAP_I2C_SYSTEST_REG] = 0x0f,
238 [OMAP_I2C_BUFSTAT_REG] = 0x10,
239 };
240
241 static const u8 reg_map_ip_v2[] = {
242 [OMAP_I2C_REV_REG] = 0x04,
243 [OMAP_I2C_IE_REG] = 0x2c,
244 [OMAP_I2C_STAT_REG] = 0x28,
245 [OMAP_I2C_IV_REG] = 0x34,
246 [OMAP_I2C_WE_REG] = 0x34,
247 [OMAP_I2C_SYSS_REG] = 0x90,
248 [OMAP_I2C_BUF_REG] = 0x94,
249 [OMAP_I2C_CNT_REG] = 0x98,
250 [OMAP_I2C_DATA_REG] = 0x9c,
251 [OMAP_I2C_SYSC_REG] = 0x10,
252 [OMAP_I2C_CON_REG] = 0xa4,
253 [OMAP_I2C_OA_REG] = 0xa8,
254 [OMAP_I2C_SA_REG] = 0xac,
255 [OMAP_I2C_PSC_REG] = 0xb0,
256 [OMAP_I2C_SCLL_REG] = 0xb4,
257 [OMAP_I2C_SCLH_REG] = 0xb8,
258 [OMAP_I2C_SYSTEST_REG] = 0xbC,
259 [OMAP_I2C_BUFSTAT_REG] = 0xc0,
260 [OMAP_I2C_IP_V2_REVNB_LO] = 0x00,
261 [OMAP_I2C_IP_V2_REVNB_HI] = 0x04,
262 [OMAP_I2C_IP_V2_IRQSTATUS_RAW] = 0x24,
263 [OMAP_I2C_IP_V2_IRQENABLE_SET] = 0x2c,
264 [OMAP_I2C_IP_V2_IRQENABLE_CLR] = 0x30,
265 };
266
omap_i2c_write_reg(struct omap_i2c_dev * i2c_dev,int reg,u16 val)267 static inline void omap_i2c_write_reg(struct omap_i2c_dev *i2c_dev,
268 int reg, u16 val)
269 {
270 __raw_writew(val, i2c_dev->base +
271 (i2c_dev->regs[reg] << i2c_dev->reg_shift));
272 }
273
omap_i2c_read_reg(struct omap_i2c_dev * i2c_dev,int reg)274 static inline u16 omap_i2c_read_reg(struct omap_i2c_dev *i2c_dev, int reg)
275 {
276 return __raw_readw(i2c_dev->base +
277 (i2c_dev->regs[reg] << i2c_dev->reg_shift));
278 }
279
__omap_i2c_init(struct omap_i2c_dev * dev)280 static void __omap_i2c_init(struct omap_i2c_dev *dev)
281 {
282
283 omap_i2c_write_reg(dev, OMAP_I2C_CON_REG, 0);
284
285 /* Setup clock prescaler to obtain approx 12MHz I2C module clock: */
286 omap_i2c_write_reg(dev, OMAP_I2C_PSC_REG, dev->pscstate);
287
288 /* SCL low and high time values */
289 omap_i2c_write_reg(dev, OMAP_I2C_SCLL_REG, dev->scllstate);
290 omap_i2c_write_reg(dev, OMAP_I2C_SCLH_REG, dev->sclhstate);
291 if (dev->rev >= OMAP_I2C_REV_ON_3430_3530)
292 omap_i2c_write_reg(dev, OMAP_I2C_WE_REG, dev->westate);
293
294 /* Take the I2C module out of reset: */
295 omap_i2c_write_reg(dev, OMAP_I2C_CON_REG, OMAP_I2C_CON_EN);
296
297 /*
298 * Don't write to this register if the IE state is 0 as it can
299 * cause deadlock.
300 */
301 if (dev->iestate)
302 omap_i2c_write_reg(dev, OMAP_I2C_IE_REG, dev->iestate);
303 }
304
omap_i2c_reset(struct omap_i2c_dev * dev)305 static int omap_i2c_reset(struct omap_i2c_dev *dev)
306 {
307 unsigned long timeout;
308 u16 sysc;
309
310 if (dev->rev >= OMAP_I2C_OMAP1_REV_2) {
311 sysc = omap_i2c_read_reg(dev, OMAP_I2C_SYSC_REG);
312
313 /* Disable I2C controller before soft reset */
314 omap_i2c_write_reg(dev, OMAP_I2C_CON_REG,
315 omap_i2c_read_reg(dev, OMAP_I2C_CON_REG) &
316 ~(OMAP_I2C_CON_EN));
317
318 omap_i2c_write_reg(dev, OMAP_I2C_SYSC_REG, SYSC_SOFTRESET_MASK);
319 /* For some reason we need to set the EN bit before the
320 * reset done bit gets set. */
321 timeout = jiffies + OMAP_I2C_TIMEOUT;
322 omap_i2c_write_reg(dev, OMAP_I2C_CON_REG, OMAP_I2C_CON_EN);
323 while (!(omap_i2c_read_reg(dev, OMAP_I2C_SYSS_REG) &
324 SYSS_RESETDONE_MASK)) {
325 if (time_after(jiffies, timeout)) {
326 dev_warn(dev->dev, "timeout waiting "
327 "for controller reset\n");
328 return -ETIMEDOUT;
329 }
330 msleep(1);
331 }
332
333 /* SYSC register is cleared by the reset; rewrite it */
334 omap_i2c_write_reg(dev, OMAP_I2C_SYSC_REG, sysc);
335
336 }
337 return 0;
338 }
339
omap_i2c_init(struct omap_i2c_dev * dev)340 static int omap_i2c_init(struct omap_i2c_dev *dev)
341 {
342 u16 psc = 0, scll = 0, sclh = 0;
343 u16 fsscll = 0, fssclh = 0, hsscll = 0, hssclh = 0;
344 unsigned long fclk_rate = 12000000;
345 unsigned long internal_clk = 0;
346 struct clk *fclk;
347
348 if (dev->rev >= OMAP_I2C_REV_ON_3430_3530) {
349 /*
350 * Enabling all wakup sources to stop I2C freezing on
351 * WFI instruction.
352 * REVISIT: Some wkup sources might not be needed.
353 */
354 dev->westate = OMAP_I2C_WE_ALL;
355 }
356
357 if (dev->flags & OMAP_I2C_FLAG_ALWAYS_ARMXOR_CLK) {
358 /*
359 * The I2C functional clock is the armxor_ck, so there's
360 * no need to get "armxor_ck" separately. Now, if OMAP2420
361 * always returns 12MHz for the functional clock, we can
362 * do this bit unconditionally.
363 */
364 fclk = clk_get(dev->dev, "fck");
365 fclk_rate = clk_get_rate(fclk);
366 clk_put(fclk);
367
368 /* TRM for 5912 says the I2C clock must be prescaled to be
369 * between 7 - 12 MHz. The XOR input clock is typically
370 * 12, 13 or 19.2 MHz. So we should have code that produces:
371 *
372 * XOR MHz Divider Prescaler
373 * 12 1 0
374 * 13 2 1
375 * 19.2 2 1
376 */
377 if (fclk_rate > 12000000)
378 psc = fclk_rate / 12000000;
379 }
380
381 if (!(dev->flags & OMAP_I2C_FLAG_SIMPLE_CLOCK)) {
382
383 /*
384 * HSI2C controller internal clk rate should be 19.2 Mhz for
385 * HS and for all modes on 2430. On 34xx we can use lower rate
386 * to get longer filter period for better noise suppression.
387 * The filter is iclk (fclk for HS) period.
388 */
389 if (dev->speed > 400 ||
390 dev->flags & OMAP_I2C_FLAG_FORCE_19200_INT_CLK)
391 internal_clk = 19200;
392 else if (dev->speed > 100)
393 internal_clk = 9600;
394 else
395 internal_clk = 4000;
396 fclk = clk_get(dev->dev, "fck");
397 fclk_rate = clk_get_rate(fclk) / 1000;
398 clk_put(fclk);
399
400 /* Compute prescaler divisor */
401 psc = fclk_rate / internal_clk;
402 psc = psc - 1;
403
404 /* If configured for High Speed */
405 if (dev->speed > 400) {
406 unsigned long scl;
407
408 /* For first phase of HS mode */
409 scl = internal_clk / 400;
410 fsscll = scl - (scl / 3) - 7;
411 fssclh = (scl / 3) - 5;
412
413 /* For second phase of HS mode */
414 scl = fclk_rate / dev->speed;
415 hsscll = scl - (scl / 3) - 7;
416 hssclh = (scl / 3) - 5;
417 } else if (dev->speed > 100) {
418 unsigned long scl;
419
420 /* Fast mode */
421 scl = internal_clk / dev->speed;
422 fsscll = scl - (scl / 3) - 7;
423 fssclh = (scl / 3) - 5;
424 } else {
425 /* Standard mode */
426 fsscll = internal_clk / (dev->speed * 2) - 7;
427 fssclh = internal_clk / (dev->speed * 2) - 5;
428 }
429 scll = (hsscll << OMAP_I2C_SCLL_HSSCLL) | fsscll;
430 sclh = (hssclh << OMAP_I2C_SCLH_HSSCLH) | fssclh;
431 } else {
432 /* Program desired operating rate */
433 fclk_rate /= (psc + 1) * 1000;
434 if (psc > 2)
435 psc = 2;
436 scll = fclk_rate / (dev->speed * 2) - 7 + psc;
437 sclh = fclk_rate / (dev->speed * 2) - 7 + psc;
438 }
439
440 dev->iestate = (OMAP_I2C_IE_XRDY | OMAP_I2C_IE_RRDY |
441 OMAP_I2C_IE_ARDY | OMAP_I2C_IE_NACK |
442 OMAP_I2C_IE_AL) | ((dev->fifo_size) ?
443 (OMAP_I2C_IE_RDR | OMAP_I2C_IE_XDR) : 0);
444
445 dev->pscstate = psc;
446 dev->scllstate = scll;
447 dev->sclhstate = sclh;
448
449 __omap_i2c_init(dev);
450
451 return 0;
452 }
453
454 /*
455 * Waiting on Bus Busy
456 */
omap_i2c_wait_for_bb(struct omap_i2c_dev * dev)457 static int omap_i2c_wait_for_bb(struct omap_i2c_dev *dev)
458 {
459 unsigned long timeout;
460
461 timeout = jiffies + OMAP_I2C_TIMEOUT;
462 while (omap_i2c_read_reg(dev, OMAP_I2C_STAT_REG) & OMAP_I2C_STAT_BB) {
463 if (time_after(jiffies, timeout)) {
464 dev_warn(dev->dev, "timeout waiting for bus ready\n");
465 return -ETIMEDOUT;
466 }
467 msleep(1);
468 }
469
470 return 0;
471 }
472
omap_i2c_resize_fifo(struct omap_i2c_dev * dev,u8 size,bool is_rx)473 static void omap_i2c_resize_fifo(struct omap_i2c_dev *dev, u8 size, bool is_rx)
474 {
475 u16 buf;
476
477 if (dev->flags & OMAP_I2C_FLAG_NO_FIFO)
478 return;
479
480 /*
481 * Set up notification threshold based on message size. We're doing
482 * this to try and avoid draining feature as much as possible. Whenever
483 * we have big messages to transfer (bigger than our total fifo size)
484 * then we might use draining feature to transfer the remaining bytes.
485 */
486
487 dev->threshold = clamp(size, (u8) 1, dev->fifo_size);
488
489 buf = omap_i2c_read_reg(dev, OMAP_I2C_BUF_REG);
490
491 if (is_rx) {
492 /* Clear RX Threshold */
493 buf &= ~(0x3f << 8);
494 buf |= ((dev->threshold - 1) << 8) | OMAP_I2C_BUF_RXFIF_CLR;
495 } else {
496 /* Clear TX Threshold */
497 buf &= ~0x3f;
498 buf |= (dev->threshold - 1) | OMAP_I2C_BUF_TXFIF_CLR;
499 }
500
501 omap_i2c_write_reg(dev, OMAP_I2C_BUF_REG, buf);
502
503 if (dev->rev < OMAP_I2C_REV_ON_3630)
504 dev->b_hw = 1; /* Enable hardware fixes */
505
506 /* calculate wakeup latency constraint for MPU */
507 if (dev->set_mpu_wkup_lat != NULL)
508 dev->latency = (1000000 * dev->threshold) /
509 (1000 * dev->speed / 8);
510 }
511
512 /*
513 * Low level master read/write transaction.
514 */
omap_i2c_xfer_msg(struct i2c_adapter * adap,struct i2c_msg * msg,int stop)515 static int omap_i2c_xfer_msg(struct i2c_adapter *adap,
516 struct i2c_msg *msg, int stop)
517 {
518 struct omap_i2c_dev *dev = i2c_get_adapdata(adap);
519 unsigned long timeout;
520 u16 w;
521
522 dev_dbg(dev->dev, "addr: 0x%04x, len: %d, flags: 0x%x, stop: %d\n",
523 msg->addr, msg->len, msg->flags, stop);
524
525 if (msg->len == 0)
526 return -EINVAL;
527
528 dev->receiver = !!(msg->flags & I2C_M_RD);
529 omap_i2c_resize_fifo(dev, msg->len, dev->receiver);
530
531 omap_i2c_write_reg(dev, OMAP_I2C_SA_REG, msg->addr);
532
533 /* REVISIT: Could the STB bit of I2C_CON be used with probing? */
534 dev->buf = msg->buf;
535 dev->buf_len = msg->len;
536
537 /* make sure writes to dev->buf_len are ordered */
538 barrier();
539
540 omap_i2c_write_reg(dev, OMAP_I2C_CNT_REG, dev->buf_len);
541
542 /* Clear the FIFO Buffers */
543 w = omap_i2c_read_reg(dev, OMAP_I2C_BUF_REG);
544 w |= OMAP_I2C_BUF_RXFIF_CLR | OMAP_I2C_BUF_TXFIF_CLR;
545 omap_i2c_write_reg(dev, OMAP_I2C_BUF_REG, w);
546
547 INIT_COMPLETION(dev->cmd_complete);
548 dev->cmd_err = 0;
549
550 w = OMAP_I2C_CON_EN | OMAP_I2C_CON_MST | OMAP_I2C_CON_STT;
551
552 /* High speed configuration */
553 if (dev->speed > 400)
554 w |= OMAP_I2C_CON_OPMODE_HS;
555
556 if (msg->flags & I2C_M_STOP)
557 stop = 1;
558 if (msg->flags & I2C_M_TEN)
559 w |= OMAP_I2C_CON_XA;
560 if (!(msg->flags & I2C_M_RD))
561 w |= OMAP_I2C_CON_TRX;
562
563 if (!dev->b_hw && stop)
564 w |= OMAP_I2C_CON_STP;
565
566 omap_i2c_write_reg(dev, OMAP_I2C_CON_REG, w);
567
568 /*
569 * Don't write stt and stp together on some hardware.
570 */
571 if (dev->b_hw && stop) {
572 unsigned long delay = jiffies + OMAP_I2C_TIMEOUT;
573 u16 con = omap_i2c_read_reg(dev, OMAP_I2C_CON_REG);
574 while (con & OMAP_I2C_CON_STT) {
575 con = omap_i2c_read_reg(dev, OMAP_I2C_CON_REG);
576
577 /* Let the user know if i2c is in a bad state */
578 if (time_after(jiffies, delay)) {
579 dev_err(dev->dev, "controller timed out "
580 "waiting for start condition to finish\n");
581 return -ETIMEDOUT;
582 }
583 cpu_relax();
584 }
585
586 w |= OMAP_I2C_CON_STP;
587 w &= ~OMAP_I2C_CON_STT;
588 omap_i2c_write_reg(dev, OMAP_I2C_CON_REG, w);
589 }
590
591 /*
592 * REVISIT: We should abort the transfer on signals, but the bus goes
593 * into arbitration and we're currently unable to recover from it.
594 */
595 timeout = wait_for_completion_timeout(&dev->cmd_complete,
596 OMAP_I2C_TIMEOUT);
597 if (timeout == 0) {
598 dev_err(dev->dev, "controller timed out\n");
599 omap_i2c_reset(dev);
600 __omap_i2c_init(dev);
601 return -ETIMEDOUT;
602 }
603
604 if (likely(!dev->cmd_err))
605 return 0;
606
607 /* We have an error */
608 if (dev->cmd_err & (OMAP_I2C_STAT_AL | OMAP_I2C_STAT_ROVR |
609 OMAP_I2C_STAT_XUDF)) {
610 omap_i2c_reset(dev);
611 __omap_i2c_init(dev);
612 return -EIO;
613 }
614
615 if (dev->cmd_err & OMAP_I2C_STAT_NACK) {
616 if (msg->flags & I2C_M_IGNORE_NAK)
617 return 0;
618 if (stop) {
619 w = omap_i2c_read_reg(dev, OMAP_I2C_CON_REG);
620 w |= OMAP_I2C_CON_STP;
621 omap_i2c_write_reg(dev, OMAP_I2C_CON_REG, w);
622 }
623 return -EREMOTEIO;
624 }
625 return -EIO;
626 }
627
628
629 /*
630 * Prepare controller for a transaction and call omap_i2c_xfer_msg
631 * to do the work during IRQ processing.
632 */
633 static int
omap_i2c_xfer(struct i2c_adapter * adap,struct i2c_msg msgs[],int num)634 omap_i2c_xfer(struct i2c_adapter *adap, struct i2c_msg msgs[], int num)
635 {
636 struct omap_i2c_dev *dev = i2c_get_adapdata(adap);
637 int i;
638 int r;
639
640 r = pm_runtime_get_sync(dev->dev);
641 if (IS_ERR_VALUE(r))
642 goto out;
643
644 r = omap_i2c_wait_for_bb(dev);
645 if (r < 0)
646 goto out;
647
648 if (dev->set_mpu_wkup_lat != NULL)
649 dev->set_mpu_wkup_lat(dev->dev, dev->latency);
650
651 for (i = 0; i < num; i++) {
652 r = omap_i2c_xfer_msg(adap, &msgs[i], (i == (num - 1)));
653 if (r != 0)
654 break;
655 }
656
657 if (r == 0)
658 r = num;
659
660 omap_i2c_wait_for_bb(dev);
661
662 if (dev->set_mpu_wkup_lat != NULL)
663 dev->set_mpu_wkup_lat(dev->dev, -1);
664
665 out:
666 pm_runtime_mark_last_busy(dev->dev);
667 pm_runtime_put_autosuspend(dev->dev);
668 return r;
669 }
670
671 static u32
omap_i2c_func(struct i2c_adapter * adap)672 omap_i2c_func(struct i2c_adapter *adap)
673 {
674 return I2C_FUNC_I2C | (I2C_FUNC_SMBUS_EMUL & ~I2C_FUNC_SMBUS_QUICK) |
675 I2C_FUNC_PROTOCOL_MANGLING;
676 }
677
678 static inline void
omap_i2c_complete_cmd(struct omap_i2c_dev * dev,u16 err)679 omap_i2c_complete_cmd(struct omap_i2c_dev *dev, u16 err)
680 {
681 dev->cmd_err |= err;
682 complete(&dev->cmd_complete);
683 }
684
685 static inline void
omap_i2c_ack_stat(struct omap_i2c_dev * dev,u16 stat)686 omap_i2c_ack_stat(struct omap_i2c_dev *dev, u16 stat)
687 {
688 omap_i2c_write_reg(dev, OMAP_I2C_STAT_REG, stat);
689 }
690
i2c_omap_errata_i207(struct omap_i2c_dev * dev,u16 stat)691 static inline void i2c_omap_errata_i207(struct omap_i2c_dev *dev, u16 stat)
692 {
693 /*
694 * I2C Errata(Errata Nos. OMAP2: 1.67, OMAP3: 1.8)
695 * Not applicable for OMAP4.
696 * Under certain rare conditions, RDR could be set again
697 * when the bus is busy, then ignore the interrupt and
698 * clear the interrupt.
699 */
700 if (stat & OMAP_I2C_STAT_RDR) {
701 /* Step 1: If RDR is set, clear it */
702 omap_i2c_ack_stat(dev, OMAP_I2C_STAT_RDR);
703
704 /* Step 2: */
705 if (!(omap_i2c_read_reg(dev, OMAP_I2C_STAT_REG)
706 & OMAP_I2C_STAT_BB)) {
707
708 /* Step 3: */
709 if (omap_i2c_read_reg(dev, OMAP_I2C_STAT_REG)
710 & OMAP_I2C_STAT_RDR) {
711 omap_i2c_ack_stat(dev, OMAP_I2C_STAT_RDR);
712 dev_dbg(dev->dev, "RDR when bus is busy.\n");
713 }
714
715 }
716 }
717 }
718
719 /* rev1 devices are apparently only on some 15xx */
720 #ifdef CONFIG_ARCH_OMAP15XX
721
722 static irqreturn_t
omap_i2c_omap1_isr(int this_irq,void * dev_id)723 omap_i2c_omap1_isr(int this_irq, void *dev_id)
724 {
725 struct omap_i2c_dev *dev = dev_id;
726 u16 iv, w;
727
728 if (pm_runtime_suspended(dev->dev))
729 return IRQ_NONE;
730
731 iv = omap_i2c_read_reg(dev, OMAP_I2C_IV_REG);
732 switch (iv) {
733 case 0x00: /* None */
734 break;
735 case 0x01: /* Arbitration lost */
736 dev_err(dev->dev, "Arbitration lost\n");
737 omap_i2c_complete_cmd(dev, OMAP_I2C_STAT_AL);
738 break;
739 case 0x02: /* No acknowledgement */
740 omap_i2c_complete_cmd(dev, OMAP_I2C_STAT_NACK);
741 omap_i2c_write_reg(dev, OMAP_I2C_CON_REG, OMAP_I2C_CON_STP);
742 break;
743 case 0x03: /* Register access ready */
744 omap_i2c_complete_cmd(dev, 0);
745 break;
746 case 0x04: /* Receive data ready */
747 if (dev->buf_len) {
748 w = omap_i2c_read_reg(dev, OMAP_I2C_DATA_REG);
749 *dev->buf++ = w;
750 dev->buf_len--;
751 if (dev->buf_len) {
752 *dev->buf++ = w >> 8;
753 dev->buf_len--;
754 }
755 } else
756 dev_err(dev->dev, "RRDY IRQ while no data requested\n");
757 break;
758 case 0x05: /* Transmit data ready */
759 if (dev->buf_len) {
760 w = *dev->buf++;
761 dev->buf_len--;
762 if (dev->buf_len) {
763 w |= *dev->buf++ << 8;
764 dev->buf_len--;
765 }
766 omap_i2c_write_reg(dev, OMAP_I2C_DATA_REG, w);
767 } else
768 dev_err(dev->dev, "XRDY IRQ while no data to send\n");
769 break;
770 default:
771 return IRQ_NONE;
772 }
773
774 return IRQ_HANDLED;
775 }
776 #else
777 #define omap_i2c_omap1_isr NULL
778 #endif
779
780 /*
781 * OMAP3430 Errata i462: When an XRDY/XDR is hit, wait for XUDF before writing
782 * data to DATA_REG. Otherwise some data bytes can be lost while transferring
783 * them from the memory to the I2C interface.
784 */
errata_omap3_i462(struct omap_i2c_dev * dev)785 static int errata_omap3_i462(struct omap_i2c_dev *dev)
786 {
787 unsigned long timeout = 10000;
788 u16 stat;
789
790 do {
791 stat = omap_i2c_read_reg(dev, OMAP_I2C_STAT_REG);
792 if (stat & OMAP_I2C_STAT_XUDF)
793 break;
794
795 if (stat & (OMAP_I2C_STAT_NACK | OMAP_I2C_STAT_AL)) {
796 omap_i2c_ack_stat(dev, (OMAP_I2C_STAT_XRDY |
797 OMAP_I2C_STAT_XDR));
798 if (stat & OMAP_I2C_STAT_NACK) {
799 dev->cmd_err |= OMAP_I2C_STAT_NACK;
800 omap_i2c_ack_stat(dev, OMAP_I2C_STAT_NACK);
801 }
802
803 if (stat & OMAP_I2C_STAT_AL) {
804 dev_err(dev->dev, "Arbitration lost\n");
805 dev->cmd_err |= OMAP_I2C_STAT_AL;
806 omap_i2c_ack_stat(dev, OMAP_I2C_STAT_AL);
807 }
808
809 return -EIO;
810 }
811
812 cpu_relax();
813 } while (--timeout);
814
815 if (!timeout) {
816 dev_err(dev->dev, "timeout waiting on XUDF bit\n");
817 return 0;
818 }
819
820 return 0;
821 }
822
omap_i2c_receive_data(struct omap_i2c_dev * dev,u8 num_bytes,bool is_rdr)823 static void omap_i2c_receive_data(struct omap_i2c_dev *dev, u8 num_bytes,
824 bool is_rdr)
825 {
826 u16 w;
827
828 while (num_bytes--) {
829 w = omap_i2c_read_reg(dev, OMAP_I2C_DATA_REG);
830 *dev->buf++ = w;
831 dev->buf_len--;
832
833 /*
834 * Data reg in 2430, omap3 and
835 * omap4 is 8 bit wide
836 */
837 if (dev->flags & OMAP_I2C_FLAG_16BIT_DATA_REG) {
838 *dev->buf++ = w >> 8;
839 dev->buf_len--;
840 }
841 }
842 }
843
omap_i2c_transmit_data(struct omap_i2c_dev * dev,u8 num_bytes,bool is_xdr)844 static int omap_i2c_transmit_data(struct omap_i2c_dev *dev, u8 num_bytes,
845 bool is_xdr)
846 {
847 u16 w;
848
849 while (num_bytes--) {
850 w = *dev->buf++;
851 dev->buf_len--;
852
853 /*
854 * Data reg in 2430, omap3 and
855 * omap4 is 8 bit wide
856 */
857 if (dev->flags & OMAP_I2C_FLAG_16BIT_DATA_REG) {
858 w |= *dev->buf++ << 8;
859 dev->buf_len--;
860 }
861
862 if (dev->errata & I2C_OMAP_ERRATA_I462) {
863 int ret;
864
865 ret = errata_omap3_i462(dev);
866 if (ret < 0)
867 return ret;
868 }
869
870 omap_i2c_write_reg(dev, OMAP_I2C_DATA_REG, w);
871 }
872
873 return 0;
874 }
875
876 static irqreturn_t
omap_i2c_isr(int irq,void * dev_id)877 omap_i2c_isr(int irq, void *dev_id)
878 {
879 struct omap_i2c_dev *dev = dev_id;
880 irqreturn_t ret = IRQ_HANDLED;
881 u16 mask;
882 u16 stat;
883
884 spin_lock(&dev->lock);
885 mask = omap_i2c_read_reg(dev, OMAP_I2C_IE_REG);
886 stat = omap_i2c_read_reg(dev, OMAP_I2C_STAT_REG);
887
888 if (stat & mask)
889 ret = IRQ_WAKE_THREAD;
890
891 spin_unlock(&dev->lock);
892
893 return ret;
894 }
895
896 static irqreturn_t
omap_i2c_isr_thread(int this_irq,void * dev_id)897 omap_i2c_isr_thread(int this_irq, void *dev_id)
898 {
899 struct omap_i2c_dev *dev = dev_id;
900 unsigned long flags;
901 u16 bits;
902 u16 stat;
903 int err = 0, count = 0;
904
905 spin_lock_irqsave(&dev->lock, flags);
906 do {
907 bits = omap_i2c_read_reg(dev, OMAP_I2C_IE_REG);
908 stat = omap_i2c_read_reg(dev, OMAP_I2C_STAT_REG);
909 stat &= bits;
910
911 /* If we're in receiver mode, ignore XDR/XRDY */
912 if (dev->receiver)
913 stat &= ~(OMAP_I2C_STAT_XDR | OMAP_I2C_STAT_XRDY);
914 else
915 stat &= ~(OMAP_I2C_STAT_RDR | OMAP_I2C_STAT_RRDY);
916
917 if (!stat) {
918 /* my work here is done */
919 goto out;
920 }
921
922 dev_dbg(dev->dev, "IRQ (ISR = 0x%04x)\n", stat);
923 if (count++ == 100) {
924 dev_warn(dev->dev, "Too much work in one IRQ\n");
925 break;
926 }
927
928 if (stat & OMAP_I2C_STAT_NACK) {
929 err |= OMAP_I2C_STAT_NACK;
930 omap_i2c_ack_stat(dev, OMAP_I2C_STAT_NACK);
931 break;
932 }
933
934 if (stat & OMAP_I2C_STAT_AL) {
935 dev_err(dev->dev, "Arbitration lost\n");
936 err |= OMAP_I2C_STAT_AL;
937 omap_i2c_ack_stat(dev, OMAP_I2C_STAT_AL);
938 break;
939 }
940
941 /*
942 * ProDB0017052: Clear ARDY bit twice
943 */
944 if (stat & (OMAP_I2C_STAT_ARDY | OMAP_I2C_STAT_NACK |
945 OMAP_I2C_STAT_AL)) {
946 omap_i2c_ack_stat(dev, (OMAP_I2C_STAT_RRDY |
947 OMAP_I2C_STAT_RDR |
948 OMAP_I2C_STAT_XRDY |
949 OMAP_I2C_STAT_XDR |
950 OMAP_I2C_STAT_ARDY));
951 break;
952 }
953
954 if (stat & OMAP_I2C_STAT_RDR) {
955 u8 num_bytes = 1;
956
957 if (dev->fifo_size)
958 num_bytes = dev->buf_len;
959
960 omap_i2c_receive_data(dev, num_bytes, true);
961
962 if (dev->errata & I2C_OMAP_ERRATA_I207)
963 i2c_omap_errata_i207(dev, stat);
964
965 omap_i2c_ack_stat(dev, OMAP_I2C_STAT_RDR);
966 continue;
967 }
968
969 if (stat & OMAP_I2C_STAT_RRDY) {
970 u8 num_bytes = 1;
971
972 if (dev->threshold)
973 num_bytes = dev->threshold;
974
975 omap_i2c_receive_data(dev, num_bytes, false);
976 omap_i2c_ack_stat(dev, OMAP_I2C_STAT_RRDY);
977 continue;
978 }
979
980 if (stat & OMAP_I2C_STAT_XDR) {
981 u8 num_bytes = 1;
982 int ret;
983
984 if (dev->fifo_size)
985 num_bytes = dev->buf_len;
986
987 ret = omap_i2c_transmit_data(dev, num_bytes, true);
988 if (ret < 0)
989 break;
990
991 omap_i2c_ack_stat(dev, OMAP_I2C_STAT_XDR);
992 continue;
993 }
994
995 if (stat & OMAP_I2C_STAT_XRDY) {
996 u8 num_bytes = 1;
997 int ret;
998
999 if (dev->threshold)
1000 num_bytes = dev->threshold;
1001
1002 ret = omap_i2c_transmit_data(dev, num_bytes, false);
1003 if (ret < 0)
1004 break;
1005
1006 omap_i2c_ack_stat(dev, OMAP_I2C_STAT_XRDY);
1007 continue;
1008 }
1009
1010 if (stat & OMAP_I2C_STAT_ROVR) {
1011 dev_err(dev->dev, "Receive overrun\n");
1012 err |= OMAP_I2C_STAT_ROVR;
1013 omap_i2c_ack_stat(dev, OMAP_I2C_STAT_ROVR);
1014 break;
1015 }
1016
1017 if (stat & OMAP_I2C_STAT_XUDF) {
1018 dev_err(dev->dev, "Transmit underflow\n");
1019 err |= OMAP_I2C_STAT_XUDF;
1020 omap_i2c_ack_stat(dev, OMAP_I2C_STAT_XUDF);
1021 break;
1022 }
1023 } while (stat);
1024
1025 omap_i2c_complete_cmd(dev, err);
1026
1027 out:
1028 spin_unlock_irqrestore(&dev->lock, flags);
1029
1030 return IRQ_HANDLED;
1031 }
1032
1033 static const struct i2c_algorithm omap_i2c_algo = {
1034 .master_xfer = omap_i2c_xfer,
1035 .functionality = omap_i2c_func,
1036 };
1037
1038 #ifdef CONFIG_OF
1039 static struct omap_i2c_bus_platform_data omap3_pdata = {
1040 .rev = OMAP_I2C_IP_VERSION_1,
1041 .flags = OMAP_I2C_FLAG_BUS_SHIFT_2,
1042 };
1043
1044 static struct omap_i2c_bus_platform_data omap4_pdata = {
1045 .rev = OMAP_I2C_IP_VERSION_2,
1046 };
1047
1048 static const struct of_device_id omap_i2c_of_match[] = {
1049 {
1050 .compatible = "ti,omap4-i2c",
1051 .data = &omap4_pdata,
1052 },
1053 {
1054 .compatible = "ti,omap3-i2c",
1055 .data = &omap3_pdata,
1056 },
1057 { },
1058 };
1059 MODULE_DEVICE_TABLE(of, omap_i2c_of_match);
1060 #endif
1061
1062 #define OMAP_I2C_SCHEME(rev) ((rev & 0xc000) >> 14)
1063
1064 #define OMAP_I2C_REV_SCHEME_0_MAJOR(rev) (rev >> 4)
1065 #define OMAP_I2C_REV_SCHEME_0_MINOR(rev) (rev & 0xf)
1066
1067 #define OMAP_I2C_REV_SCHEME_1_MAJOR(rev) ((rev & 0x0700) >> 7)
1068 #define OMAP_I2C_REV_SCHEME_1_MINOR(rev) (rev & 0x1f)
1069 #define OMAP_I2C_SCHEME_0 0
1070 #define OMAP_I2C_SCHEME_1 1
1071
1072 static int
omap_i2c_probe(struct platform_device * pdev)1073 omap_i2c_probe(struct platform_device *pdev)
1074 {
1075 struct omap_i2c_dev *dev;
1076 struct i2c_adapter *adap;
1077 struct resource *mem;
1078 const struct omap_i2c_bus_platform_data *pdata =
1079 pdev->dev.platform_data;
1080 struct device_node *node = pdev->dev.of_node;
1081 const struct of_device_id *match;
1082 int irq;
1083 int r;
1084 u32 rev;
1085 u16 minor, major, scheme;
1086
1087 /* NOTE: driver uses the static register mapping */
1088 mem = platform_get_resource(pdev, IORESOURCE_MEM, 0);
1089 if (!mem) {
1090 dev_err(&pdev->dev, "no mem resource?\n");
1091 return -ENODEV;
1092 }
1093
1094 irq = platform_get_irq(pdev, 0);
1095 if (irq < 0) {
1096 dev_err(&pdev->dev, "no irq resource?\n");
1097 return irq;
1098 }
1099
1100 dev = devm_kzalloc(&pdev->dev, sizeof(struct omap_i2c_dev), GFP_KERNEL);
1101 if (!dev) {
1102 dev_err(&pdev->dev, "Menory allocation failed\n");
1103 return -ENOMEM;
1104 }
1105
1106 dev->base = devm_ioremap_resource(&pdev->dev, mem);
1107 if (IS_ERR(dev->base))
1108 return PTR_ERR(dev->base);
1109
1110 match = of_match_device(of_match_ptr(omap_i2c_of_match), &pdev->dev);
1111 if (match) {
1112 u32 freq = 100000; /* default to 100000 Hz */
1113
1114 pdata = match->data;
1115 dev->flags = pdata->flags;
1116
1117 of_property_read_u32(node, "clock-frequency", &freq);
1118 /* convert DT freq value in Hz into kHz for speed */
1119 dev->speed = freq / 1000;
1120 } else if (pdata != NULL) {
1121 dev->speed = pdata->clkrate;
1122 dev->flags = pdata->flags;
1123 dev->set_mpu_wkup_lat = pdata->set_mpu_wkup_lat;
1124 }
1125
1126 dev->pins = devm_pinctrl_get_select_default(&pdev->dev);
1127 if (IS_ERR(dev->pins)) {
1128 if (PTR_ERR(dev->pins) == -EPROBE_DEFER)
1129 return -EPROBE_DEFER;
1130
1131 dev_warn(&pdev->dev, "did not get pins for i2c error: %li\n",
1132 PTR_ERR(dev->pins));
1133 dev->pins = NULL;
1134 }
1135
1136 dev->dev = &pdev->dev;
1137 dev->irq = irq;
1138
1139 spin_lock_init(&dev->lock);
1140
1141 platform_set_drvdata(pdev, dev);
1142 init_completion(&dev->cmd_complete);
1143
1144 dev->reg_shift = (dev->flags >> OMAP_I2C_FLAG_BUS_SHIFT__SHIFT) & 3;
1145
1146 pm_runtime_enable(dev->dev);
1147 pm_runtime_set_autosuspend_delay(dev->dev, OMAP_I2C_PM_TIMEOUT);
1148 pm_runtime_use_autosuspend(dev->dev);
1149
1150 r = pm_runtime_get_sync(dev->dev);
1151 if (IS_ERR_VALUE(r))
1152 goto err_free_mem;
1153
1154 /*
1155 * Read the Rev hi bit-[15:14] ie scheme this is 1 indicates ver2.
1156 * On omap1/3/2 Offset 4 is IE Reg the bit [15:14] is 0 at reset.
1157 * Also since the omap_i2c_read_reg uses reg_map_ip_* a
1158 * raw_readw is done.
1159 */
1160 rev = __raw_readw(dev->base + 0x04);
1161
1162 scheme = OMAP_I2C_SCHEME(rev);
1163 switch (scheme) {
1164 case OMAP_I2C_SCHEME_0:
1165 dev->regs = (u8 *)reg_map_ip_v1;
1166 dev->rev = omap_i2c_read_reg(dev, OMAP_I2C_REV_REG);
1167 minor = OMAP_I2C_REV_SCHEME_0_MAJOR(dev->rev);
1168 major = OMAP_I2C_REV_SCHEME_0_MAJOR(dev->rev);
1169 break;
1170 case OMAP_I2C_SCHEME_1:
1171 /* FALLTHROUGH */
1172 default:
1173 dev->regs = (u8 *)reg_map_ip_v2;
1174 rev = (rev << 16) |
1175 omap_i2c_read_reg(dev, OMAP_I2C_IP_V2_REVNB_LO);
1176 minor = OMAP_I2C_REV_SCHEME_1_MINOR(rev);
1177 major = OMAP_I2C_REV_SCHEME_1_MAJOR(rev);
1178 dev->rev = rev;
1179 }
1180
1181 dev->errata = 0;
1182
1183 if (dev->rev >= OMAP_I2C_REV_ON_2430 &&
1184 dev->rev < OMAP_I2C_REV_ON_4430_PLUS)
1185 dev->errata |= I2C_OMAP_ERRATA_I207;
1186
1187 if (dev->rev <= OMAP_I2C_REV_ON_3430_3530)
1188 dev->errata |= I2C_OMAP_ERRATA_I462;
1189
1190 if (!(dev->flags & OMAP_I2C_FLAG_NO_FIFO)) {
1191 u16 s;
1192
1193 /* Set up the fifo size - Get total size */
1194 s = (omap_i2c_read_reg(dev, OMAP_I2C_BUFSTAT_REG) >> 14) & 0x3;
1195 dev->fifo_size = 0x8 << s;
1196
1197 /*
1198 * Set up notification threshold as half the total available
1199 * size. This is to ensure that we can handle the status on int
1200 * call back latencies.
1201 */
1202
1203 dev->fifo_size = (dev->fifo_size / 2);
1204
1205 if (dev->rev < OMAP_I2C_REV_ON_3630)
1206 dev->b_hw = 1; /* Enable hardware fixes */
1207
1208 /* calculate wakeup latency constraint for MPU */
1209 if (dev->set_mpu_wkup_lat != NULL)
1210 dev->latency = (1000000 * dev->fifo_size) /
1211 (1000 * dev->speed / 8);
1212 }
1213
1214 /* reset ASAP, clearing any IRQs */
1215 omap_i2c_init(dev);
1216
1217 if (dev->rev < OMAP_I2C_OMAP1_REV_2)
1218 r = devm_request_irq(&pdev->dev, dev->irq, omap_i2c_omap1_isr,
1219 IRQF_NO_SUSPEND, pdev->name, dev);
1220 else
1221 r = devm_request_threaded_irq(&pdev->dev, dev->irq,
1222 omap_i2c_isr, omap_i2c_isr_thread,
1223 IRQF_NO_SUSPEND | IRQF_ONESHOT,
1224 pdev->name, dev);
1225
1226 if (r) {
1227 dev_err(dev->dev, "failure requesting irq %i\n", dev->irq);
1228 goto err_unuse_clocks;
1229 }
1230
1231 adap = &dev->adapter;
1232 i2c_set_adapdata(adap, dev);
1233 adap->owner = THIS_MODULE;
1234 adap->class = I2C_CLASS_HWMON;
1235 strlcpy(adap->name, "OMAP I2C adapter", sizeof(adap->name));
1236 adap->algo = &omap_i2c_algo;
1237 adap->dev.parent = &pdev->dev;
1238 adap->dev.of_node = pdev->dev.of_node;
1239
1240 /* i2c device drivers may be active on return from add_adapter() */
1241 adap->nr = pdev->id;
1242 r = i2c_add_numbered_adapter(adap);
1243 if (r) {
1244 dev_err(dev->dev, "failure adding adapter\n");
1245 goto err_unuse_clocks;
1246 }
1247
1248 dev_info(dev->dev, "bus %d rev%d.%d at %d kHz\n", adap->nr,
1249 major, minor, dev->speed);
1250
1251 of_i2c_register_devices(adap);
1252
1253 pm_runtime_mark_last_busy(dev->dev);
1254 pm_runtime_put_autosuspend(dev->dev);
1255
1256 return 0;
1257
1258 err_unuse_clocks:
1259 omap_i2c_write_reg(dev, OMAP_I2C_CON_REG, 0);
1260 pm_runtime_put(dev->dev);
1261 pm_runtime_disable(&pdev->dev);
1262 err_free_mem:
1263
1264 return r;
1265 }
1266
omap_i2c_remove(struct platform_device * pdev)1267 static int omap_i2c_remove(struct platform_device *pdev)
1268 {
1269 struct omap_i2c_dev *dev = platform_get_drvdata(pdev);
1270 int ret;
1271
1272 i2c_del_adapter(&dev->adapter);
1273 ret = pm_runtime_get_sync(&pdev->dev);
1274 if (IS_ERR_VALUE(ret))
1275 return ret;
1276
1277 omap_i2c_write_reg(dev, OMAP_I2C_CON_REG, 0);
1278 pm_runtime_put(&pdev->dev);
1279 pm_runtime_disable(&pdev->dev);
1280 return 0;
1281 }
1282
1283 #ifdef CONFIG_PM
1284 #ifdef CONFIG_PM_RUNTIME
omap_i2c_runtime_suspend(struct device * dev)1285 static int omap_i2c_runtime_suspend(struct device *dev)
1286 {
1287 struct platform_device *pdev = to_platform_device(dev);
1288 struct omap_i2c_dev *_dev = platform_get_drvdata(pdev);
1289
1290 _dev->iestate = omap_i2c_read_reg(_dev, OMAP_I2C_IE_REG);
1291
1292 omap_i2c_write_reg(_dev, OMAP_I2C_IE_REG, 0);
1293
1294 if (_dev->rev < OMAP_I2C_OMAP1_REV_2) {
1295 omap_i2c_read_reg(_dev, OMAP_I2C_IV_REG); /* Read clears */
1296 } else {
1297 omap_i2c_write_reg(_dev, OMAP_I2C_STAT_REG, _dev->iestate);
1298
1299 /* Flush posted write */
1300 omap_i2c_read_reg(_dev, OMAP_I2C_STAT_REG);
1301 }
1302
1303 return 0;
1304 }
1305
omap_i2c_runtime_resume(struct device * dev)1306 static int omap_i2c_runtime_resume(struct device *dev)
1307 {
1308 struct platform_device *pdev = to_platform_device(dev);
1309 struct omap_i2c_dev *_dev = platform_get_drvdata(pdev);
1310
1311 if (!_dev->regs)
1312 return 0;
1313
1314 __omap_i2c_init(_dev);
1315
1316 return 0;
1317 }
1318 #endif /* CONFIG_PM_RUNTIME */
1319
1320 static struct dev_pm_ops omap_i2c_pm_ops = {
1321 SET_RUNTIME_PM_OPS(omap_i2c_runtime_suspend,
1322 omap_i2c_runtime_resume, NULL)
1323 };
1324 #define OMAP_I2C_PM_OPS (&omap_i2c_pm_ops)
1325 #else
1326 #define OMAP_I2C_PM_OPS NULL
1327 #endif /* CONFIG_PM */
1328
1329 static struct platform_driver omap_i2c_driver = {
1330 .probe = omap_i2c_probe,
1331 .remove = omap_i2c_remove,
1332 .driver = {
1333 .name = "omap_i2c",
1334 .owner = THIS_MODULE,
1335 .pm = OMAP_I2C_PM_OPS,
1336 .of_match_table = of_match_ptr(omap_i2c_of_match),
1337 },
1338 };
1339
1340 /* I2C may be needed to bring up other drivers */
1341 static int __init
omap_i2c_init_driver(void)1342 omap_i2c_init_driver(void)
1343 {
1344 return platform_driver_register(&omap_i2c_driver);
1345 }
1346 subsys_initcall(omap_i2c_init_driver);
1347
omap_i2c_exit_driver(void)1348 static void __exit omap_i2c_exit_driver(void)
1349 {
1350 platform_driver_unregister(&omap_i2c_driver);
1351 }
1352 module_exit(omap_i2c_exit_driver);
1353
1354 MODULE_AUTHOR("MontaVista Software, Inc. (and others)");
1355 MODULE_DESCRIPTION("TI OMAP I2C bus adapter");
1356 MODULE_LICENSE("GPL");
1357 MODULE_ALIAS("platform:omap_i2c");
1358