2 * TI OMAP I2C master mode driver
4 * Copyright (C) 2003 MontaVista Software, Inc.
5 * Copyright (C) 2005 Nokia Corporation
6 * Copyright (C) 2004 - 2007 Texas Instruments.
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>
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.
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.
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.
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>
40 #include <linux/slab.h>
41 #include <linux/i2c-omap.h>
42 #include <linux/pm_runtime.h>
44 /* I2C controller revisions */
45 #define OMAP_I2C_REV_2 0x20
47 /* I2C controller revisions present on specific hardware */
48 #define OMAP_I2C_REV_ON_2430 0x36
49 #define OMAP_I2C_REV_ON_3430 0x3C
50 #define OMAP_I2C_REV_ON_4430 0x40
52 /* timeout waiting for the controller to respond */
53 #define OMAP_I2C_TIMEOUT (msecs_to_jiffies(1000))
55 /* For OMAP3 I2C_IV has changed to I2C_WE (wakeup enable) */
77 OMAP_I2C_IRQSTATUS_RAW
,
78 OMAP_I2C_IRQENABLE_SET
,
79 OMAP_I2C_IRQENABLE_CLR
,
82 /* I2C Interrupt Enable Register (OMAP_I2C_IE): */
83 #define OMAP_I2C_IE_XDR (1 << 14) /* TX Buffer drain int enable */
84 #define OMAP_I2C_IE_RDR (1 << 13) /* RX Buffer drain int enable */
85 #define OMAP_I2C_IE_XRDY (1 << 4) /* TX data ready int enable */
86 #define OMAP_I2C_IE_RRDY (1 << 3) /* RX data ready int enable */
87 #define OMAP_I2C_IE_ARDY (1 << 2) /* Access ready int enable */
88 #define OMAP_I2C_IE_NACK (1 << 1) /* No ack interrupt enable */
89 #define OMAP_I2C_IE_AL (1 << 0) /* Arbitration lost int ena */
91 /* I2C Status Register (OMAP_I2C_STAT): */
92 #define OMAP_I2C_STAT_XDR (1 << 14) /* TX Buffer draining */
93 #define OMAP_I2C_STAT_RDR (1 << 13) /* RX Buffer draining */
94 #define OMAP_I2C_STAT_BB (1 << 12) /* Bus busy */
95 #define OMAP_I2C_STAT_ROVR (1 << 11) /* Receive overrun */
96 #define OMAP_I2C_STAT_XUDF (1 << 10) /* Transmit underflow */
97 #define OMAP_I2C_STAT_AAS (1 << 9) /* Address as slave */
98 #define OMAP_I2C_STAT_AD0 (1 << 8) /* Address zero */
99 #define OMAP_I2C_STAT_XRDY (1 << 4) /* Transmit data ready */
100 #define OMAP_I2C_STAT_RRDY (1 << 3) /* Receive data ready */
101 #define OMAP_I2C_STAT_ARDY (1 << 2) /* Register access ready */
102 #define OMAP_I2C_STAT_NACK (1 << 1) /* No ack interrupt enable */
103 #define OMAP_I2C_STAT_AL (1 << 0) /* Arbitration lost int ena */
105 /* I2C WE wakeup enable register */
106 #define OMAP_I2C_WE_XDR_WE (1 << 14) /* TX drain wakup */
107 #define OMAP_I2C_WE_RDR_WE (1 << 13) /* RX drain wakeup */
108 #define OMAP_I2C_WE_AAS_WE (1 << 9) /* Address as slave wakeup*/
109 #define OMAP_I2C_WE_BF_WE (1 << 8) /* Bus free wakeup */
110 #define OMAP_I2C_WE_STC_WE (1 << 6) /* Start condition wakeup */
111 #define OMAP_I2C_WE_GC_WE (1 << 5) /* General call wakeup */
112 #define OMAP_I2C_WE_DRDY_WE (1 << 3) /* TX/RX data ready wakeup */
113 #define OMAP_I2C_WE_ARDY_WE (1 << 2) /* Reg access ready wakeup */
114 #define OMAP_I2C_WE_NACK_WE (1 << 1) /* No acknowledgment wakeup */
115 #define OMAP_I2C_WE_AL_WE (1 << 0) /* Arbitration lost wakeup */
117 #define OMAP_I2C_WE_ALL (OMAP_I2C_WE_XDR_WE | OMAP_I2C_WE_RDR_WE | \
118 OMAP_I2C_WE_AAS_WE | OMAP_I2C_WE_BF_WE | \
119 OMAP_I2C_WE_STC_WE | OMAP_I2C_WE_GC_WE | \
120 OMAP_I2C_WE_DRDY_WE | OMAP_I2C_WE_ARDY_WE | \
121 OMAP_I2C_WE_NACK_WE | OMAP_I2C_WE_AL_WE)
123 /* I2C Buffer Configuration Register (OMAP_I2C_BUF): */
124 #define OMAP_I2C_BUF_RDMA_EN (1 << 15) /* RX DMA channel enable */
125 #define OMAP_I2C_BUF_RXFIF_CLR (1 << 14) /* RX FIFO Clear */
126 #define OMAP_I2C_BUF_XDMA_EN (1 << 7) /* TX DMA channel enable */
127 #define OMAP_I2C_BUF_TXFIF_CLR (1 << 6) /* TX FIFO Clear */
129 /* I2C Configuration Register (OMAP_I2C_CON): */
130 #define OMAP_I2C_CON_EN (1 << 15) /* I2C module enable */
131 #define OMAP_I2C_CON_BE (1 << 14) /* Big endian mode */
132 #define OMAP_I2C_CON_OPMODE_HS (1 << 12) /* High Speed support */
133 #define OMAP_I2C_CON_STB (1 << 11) /* Start byte mode (master) */
134 #define OMAP_I2C_CON_MST (1 << 10) /* Master/slave mode */
135 #define OMAP_I2C_CON_TRX (1 << 9) /* TX/RX mode (master only) */
136 #define OMAP_I2C_CON_XA (1 << 8) /* Expand address */
137 #define OMAP_I2C_CON_RM (1 << 2) /* Repeat mode (master only) */
138 #define OMAP_I2C_CON_STP (1 << 1) /* Stop cond (master only) */
139 #define OMAP_I2C_CON_STT (1 << 0) /* Start condition (master) */
141 /* I2C SCL time value when Master */
142 #define OMAP_I2C_SCLL_HSSCLL 8
143 #define OMAP_I2C_SCLH_HSSCLH 8
145 /* I2C System Test Register (OMAP_I2C_SYSTEST): */
147 #define OMAP_I2C_SYSTEST_ST_EN (1 << 15) /* System test enable */
148 #define OMAP_I2C_SYSTEST_FREE (1 << 14) /* Free running mode */
149 #define OMAP_I2C_SYSTEST_TMODE_MASK (3 << 12) /* Test mode select */
150 #define OMAP_I2C_SYSTEST_TMODE_SHIFT (12) /* Test mode select */
151 #define OMAP_I2C_SYSTEST_SCL_I (1 << 3) /* SCL line sense in */
152 #define OMAP_I2C_SYSTEST_SCL_O (1 << 2) /* SCL line drive out */
153 #define OMAP_I2C_SYSTEST_SDA_I (1 << 1) /* SDA line sense in */
154 #define OMAP_I2C_SYSTEST_SDA_O (1 << 0) /* SDA line drive out */
157 /* OCP_SYSSTATUS bit definitions */
158 #define SYSS_RESETDONE_MASK (1 << 0)
160 /* OCP_SYSCONFIG bit definitions */
161 #define SYSC_CLOCKACTIVITY_MASK (0x3 << 8)
162 #define SYSC_SIDLEMODE_MASK (0x3 << 3)
163 #define SYSC_ENAWAKEUP_MASK (1 << 2)
164 #define SYSC_SOFTRESET_MASK (1 << 1)
165 #define SYSC_AUTOIDLE_MASK (1 << 0)
167 #define SYSC_IDLEMODE_SMART 0x2
168 #define SYSC_CLOCKACTIVITY_FCLK 0x2
170 /* Errata definitions */
171 #define I2C_OMAP_ERRATA_I207 (1 << 0)
172 #define I2C_OMAP3_1P153 (1 << 1)
174 struct omap_i2c_dev
{
176 void __iomem
*base
; /* virtual */
178 int reg_shift
; /* bit shift for I2C register addresses */
179 struct completion cmd_complete
;
180 struct resource
*ioarea
;
181 u32 latency
; /* maximum mpu wkup latency */
182 void (*set_mpu_wkup_lat
)(struct device
*dev
,
184 u32 speed
; /* Speed of bus in Khz */
189 struct i2c_adapter adapter
;
190 u8 fifo_size
; /* use as flag and value
191 * fifo_size==0 implies no fifo
192 * if set, should be trsh+1
195 unsigned b_hw
:1; /* bad h/w fixes */
197 u16 iestate
; /* Saved interrupt register */
207 const 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,
228 const 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
] = 0x10,
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,
254 static inline void omap_i2c_write_reg(struct omap_i2c_dev
*i2c_dev
,
257 __raw_writew(val
, i2c_dev
->base
+
258 (i2c_dev
->regs
[reg
] << i2c_dev
->reg_shift
));
261 static inline u16
omap_i2c_read_reg(struct omap_i2c_dev
*i2c_dev
, int reg
)
263 return __raw_readw(i2c_dev
->base
+
264 (i2c_dev
->regs
[reg
] << i2c_dev
->reg_shift
));
267 static void omap_i2c_unidle(struct omap_i2c_dev
*dev
)
269 struct platform_device
*pdev
;
270 struct omap_i2c_bus_platform_data
*pdata
;
274 pdev
= to_platform_device(dev
->dev
);
275 pdata
= pdev
->dev
.platform_data
;
277 pm_runtime_get_sync(&pdev
->dev
);
279 if (cpu_is_omap34xx()) {
280 omap_i2c_write_reg(dev
, OMAP_I2C_CON_REG
, 0);
281 omap_i2c_write_reg(dev
, OMAP_I2C_PSC_REG
, dev
->pscstate
);
282 omap_i2c_write_reg(dev
, OMAP_I2C_SCLL_REG
, dev
->scllstate
);
283 omap_i2c_write_reg(dev
, OMAP_I2C_SCLH_REG
, dev
->sclhstate
);
284 omap_i2c_write_reg(dev
, OMAP_I2C_BUF_REG
, dev
->bufstate
);
285 omap_i2c_write_reg(dev
, OMAP_I2C_SYSC_REG
, dev
->syscstate
);
286 omap_i2c_write_reg(dev
, OMAP_I2C_WE_REG
, dev
->westate
);
287 omap_i2c_write_reg(dev
, OMAP_I2C_CON_REG
, OMAP_I2C_CON_EN
);
292 * Don't write to this register if the IE state is 0 as it can
296 omap_i2c_write_reg(dev
, OMAP_I2C_IE_REG
, dev
->iestate
);
299 static void omap_i2c_idle(struct omap_i2c_dev
*dev
)
301 struct platform_device
*pdev
;
302 struct omap_i2c_bus_platform_data
*pdata
;
307 pdev
= to_platform_device(dev
->dev
);
308 pdata
= pdev
->dev
.platform_data
;
310 dev
->iestate
= omap_i2c_read_reg(dev
, OMAP_I2C_IE_REG
);
311 if (dev
->rev
>= OMAP_I2C_REV_ON_4430
)
312 omap_i2c_write_reg(dev
, OMAP_I2C_IRQENABLE_CLR
, 1);
314 omap_i2c_write_reg(dev
, OMAP_I2C_IE_REG
, 0);
316 if (dev
->rev
< OMAP_I2C_REV_2
) {
317 iv
= omap_i2c_read_reg(dev
, OMAP_I2C_IV_REG
); /* Read clears */
319 omap_i2c_write_reg(dev
, OMAP_I2C_STAT_REG
, dev
->iestate
);
321 /* Flush posted write before the dev->idle store occurs */
322 omap_i2c_read_reg(dev
, OMAP_I2C_STAT_REG
);
326 pm_runtime_put_sync(&pdev
->dev
);
329 static int omap_i2c_init(struct omap_i2c_dev
*dev
)
331 u16 psc
= 0, scll
= 0, sclh
= 0, buf
= 0;
332 u16 fsscll
= 0, fssclh
= 0, hsscll
= 0, hssclh
= 0;
333 unsigned long fclk_rate
= 12000000;
334 unsigned long timeout
;
335 unsigned long internal_clk
= 0;
338 if (dev
->rev
>= OMAP_I2C_REV_2
) {
339 /* Disable I2C controller before soft reset */
340 omap_i2c_write_reg(dev
, OMAP_I2C_CON_REG
,
341 omap_i2c_read_reg(dev
, OMAP_I2C_CON_REG
) &
344 omap_i2c_write_reg(dev
, OMAP_I2C_SYSC_REG
, SYSC_SOFTRESET_MASK
);
345 /* For some reason we need to set the EN bit before the
346 * reset done bit gets set. */
347 timeout
= jiffies
+ OMAP_I2C_TIMEOUT
;
348 omap_i2c_write_reg(dev
, OMAP_I2C_CON_REG
, OMAP_I2C_CON_EN
);
349 while (!(omap_i2c_read_reg(dev
, OMAP_I2C_SYSS_REG
) &
350 SYSS_RESETDONE_MASK
)) {
351 if (time_after(jiffies
, timeout
)) {
352 dev_warn(dev
->dev
, "timeout waiting "
353 "for controller reset\n");
359 /* SYSC register is cleared by the reset; rewrite it */
360 if (dev
->rev
== OMAP_I2C_REV_ON_2430
) {
362 omap_i2c_write_reg(dev
, OMAP_I2C_SYSC_REG
,
365 } else if (dev
->rev
>= OMAP_I2C_REV_ON_3430
) {
366 dev
->syscstate
= SYSC_AUTOIDLE_MASK
;
367 dev
->syscstate
|= SYSC_ENAWAKEUP_MASK
;
368 dev
->syscstate
|= (SYSC_IDLEMODE_SMART
<<
369 __ffs(SYSC_SIDLEMODE_MASK
));
370 dev
->syscstate
|= (SYSC_CLOCKACTIVITY_FCLK
<<
371 __ffs(SYSC_CLOCKACTIVITY_MASK
));
373 omap_i2c_write_reg(dev
, OMAP_I2C_SYSC_REG
,
376 * Enabling all wakup sources to stop I2C freezing on
378 * REVISIT: Some wkup sources might not be needed.
380 dev
->westate
= OMAP_I2C_WE_ALL
;
381 omap_i2c_write_reg(dev
, OMAP_I2C_WE_REG
, dev
->westate
);
384 omap_i2c_write_reg(dev
, OMAP_I2C_CON_REG
, 0);
386 if (cpu_class_is_omap1()) {
388 * The I2C functional clock is the armxor_ck, so there's
389 * no need to get "armxor_ck" separately. Now, if OMAP2420
390 * always returns 12MHz for the functional clock, we can
391 * do this bit unconditionally.
393 fclk
= clk_get(dev
->dev
, "fck");
394 fclk_rate
= clk_get_rate(fclk
);
397 /* TRM for 5912 says the I2C clock must be prescaled to be
398 * between 7 - 12 MHz. The XOR input clock is typically
399 * 12, 13 or 19.2 MHz. So we should have code that produces:
401 * XOR MHz Divider Prescaler
406 if (fclk_rate
> 12000000)
407 psc
= fclk_rate
/ 12000000;
410 if (!(cpu_class_is_omap1() || cpu_is_omap2420())) {
413 * HSI2C controller internal clk rate should be 19.2 Mhz for
414 * HS and for all modes on 2430. On 34xx we can use lower rate
415 * to get longer filter period for better noise suppression.
416 * The filter is iclk (fclk for HS) period.
418 if (dev
->speed
> 400 || cpu_is_omap2430())
419 internal_clk
= 19200;
420 else if (dev
->speed
> 100)
424 fclk
= clk_get(dev
->dev
, "fck");
425 fclk_rate
= clk_get_rate(fclk
) / 1000;
428 /* Compute prescaler divisor */
429 psc
= fclk_rate
/ internal_clk
;
432 /* If configured for High Speed */
433 if (dev
->speed
> 400) {
436 /* For first phase of HS mode */
437 scl
= internal_clk
/ 400;
438 fsscll
= scl
- (scl
/ 3) - 7;
439 fssclh
= (scl
/ 3) - 5;
441 /* For second phase of HS mode */
442 scl
= fclk_rate
/ dev
->speed
;
443 hsscll
= scl
- (scl
/ 3) - 7;
444 hssclh
= (scl
/ 3) - 5;
445 } else if (dev
->speed
> 100) {
449 scl
= internal_clk
/ dev
->speed
;
450 fsscll
= scl
- (scl
/ 3) - 7;
451 fssclh
= (scl
/ 3) - 5;
454 fsscll
= internal_clk
/ (dev
->speed
* 2) - 7;
455 fssclh
= internal_clk
/ (dev
->speed
* 2) - 5;
457 scll
= (hsscll
<< OMAP_I2C_SCLL_HSSCLL
) | fsscll
;
458 sclh
= (hssclh
<< OMAP_I2C_SCLH_HSSCLH
) | fssclh
;
460 /* Program desired operating rate */
461 fclk_rate
/= (psc
+ 1) * 1000;
464 scll
= fclk_rate
/ (dev
->speed
* 2) - 7 + psc
;
465 sclh
= fclk_rate
/ (dev
->speed
* 2) - 7 + psc
;
468 /* Setup clock prescaler to obtain approx 12MHz I2C module clock: */
469 omap_i2c_write_reg(dev
, OMAP_I2C_PSC_REG
, psc
);
471 /* SCL low and high time values */
472 omap_i2c_write_reg(dev
, OMAP_I2C_SCLL_REG
, scll
);
473 omap_i2c_write_reg(dev
, OMAP_I2C_SCLH_REG
, sclh
);
475 if (dev
->fifo_size
) {
476 /* Note: setup required fifo size - 1. RTRSH and XTRSH */
477 buf
= (dev
->fifo_size
- 1) << 8 | OMAP_I2C_BUF_RXFIF_CLR
|
478 (dev
->fifo_size
- 1) | OMAP_I2C_BUF_TXFIF_CLR
;
479 omap_i2c_write_reg(dev
, OMAP_I2C_BUF_REG
, buf
);
482 /* Take the I2C module out of reset: */
483 omap_i2c_write_reg(dev
, OMAP_I2C_CON_REG
, OMAP_I2C_CON_EN
);
487 if (cpu_is_omap2430() || cpu_is_omap34xx())
488 dev
->errata
|= I2C_OMAP_ERRATA_I207
;
490 /* Enable interrupts */
491 dev
->iestate
= (OMAP_I2C_IE_XRDY
| OMAP_I2C_IE_RRDY
|
492 OMAP_I2C_IE_ARDY
| OMAP_I2C_IE_NACK
|
493 OMAP_I2C_IE_AL
) | ((dev
->fifo_size
) ?
494 (OMAP_I2C_IE_RDR
| OMAP_I2C_IE_XDR
) : 0);
495 omap_i2c_write_reg(dev
, OMAP_I2C_IE_REG
, dev
->iestate
);
496 if (cpu_is_omap34xx()) {
498 dev
->scllstate
= scll
;
499 dev
->sclhstate
= sclh
;
506 * Waiting on Bus Busy
508 static int omap_i2c_wait_for_bb(struct omap_i2c_dev
*dev
)
510 unsigned long timeout
;
512 timeout
= jiffies
+ OMAP_I2C_TIMEOUT
;
513 while (omap_i2c_read_reg(dev
, OMAP_I2C_STAT_REG
) & OMAP_I2C_STAT_BB
) {
514 if (time_after(jiffies
, timeout
)) {
515 dev_warn(dev
->dev
, "timeout waiting for bus ready\n");
525 * Low level master read/write transaction.
527 static int omap_i2c_xfer_msg(struct i2c_adapter
*adap
,
528 struct i2c_msg
*msg
, int stop
)
530 struct omap_i2c_dev
*dev
= i2c_get_adapdata(adap
);
534 dev_dbg(dev
->dev
, "addr: 0x%04x, len: %d, flags: 0x%x, stop: %d\n",
535 msg
->addr
, msg
->len
, msg
->flags
, stop
);
540 omap_i2c_write_reg(dev
, OMAP_I2C_SA_REG
, msg
->addr
);
542 /* REVISIT: Could the STB bit of I2C_CON be used with probing? */
544 dev
->buf_len
= msg
->len
;
546 omap_i2c_write_reg(dev
, OMAP_I2C_CNT_REG
, dev
->buf_len
);
548 /* Clear the FIFO Buffers */
549 w
= omap_i2c_read_reg(dev
, OMAP_I2C_BUF_REG
);
550 w
|= OMAP_I2C_BUF_RXFIF_CLR
| OMAP_I2C_BUF_TXFIF_CLR
;
551 omap_i2c_write_reg(dev
, OMAP_I2C_BUF_REG
, w
);
553 init_completion(&dev
->cmd_complete
);
556 w
= OMAP_I2C_CON_EN
| OMAP_I2C_CON_MST
| OMAP_I2C_CON_STT
;
558 /* High speed configuration */
559 if (dev
->speed
> 400)
560 w
|= OMAP_I2C_CON_OPMODE_HS
;
562 if (msg
->flags
& I2C_M_TEN
)
563 w
|= OMAP_I2C_CON_XA
;
564 if (!(msg
->flags
& I2C_M_RD
))
565 w
|= OMAP_I2C_CON_TRX
;
567 if (!dev
->b_hw
&& stop
)
568 w
|= OMAP_I2C_CON_STP
;
570 omap_i2c_write_reg(dev
, OMAP_I2C_CON_REG
, w
);
573 * Don't write stt and stp together on some hardware.
575 if (dev
->b_hw
&& stop
) {
576 unsigned long delay
= jiffies
+ OMAP_I2C_TIMEOUT
;
577 u16 con
= omap_i2c_read_reg(dev
, OMAP_I2C_CON_REG
);
578 while (con
& OMAP_I2C_CON_STT
) {
579 con
= omap_i2c_read_reg(dev
, OMAP_I2C_CON_REG
);
581 /* Let the user know if i2c is in a bad state */
582 if (time_after(jiffies
, delay
)) {
583 dev_err(dev
->dev
, "controller timed out "
584 "waiting for start condition to finish\n");
590 w
|= OMAP_I2C_CON_STP
;
591 w
&= ~OMAP_I2C_CON_STT
;
592 omap_i2c_write_reg(dev
, OMAP_I2C_CON_REG
, w
);
596 * REVISIT: We should abort the transfer on signals, but the bus goes
597 * into arbitration and we're currently unable to recover from it.
599 r
= wait_for_completion_timeout(&dev
->cmd_complete
,
605 dev_err(dev
->dev
, "controller timed out\n");
610 if (likely(!dev
->cmd_err
))
613 /* We have an error */
614 if (dev
->cmd_err
& (OMAP_I2C_STAT_AL
| OMAP_I2C_STAT_ROVR
|
615 OMAP_I2C_STAT_XUDF
)) {
620 if (dev
->cmd_err
& OMAP_I2C_STAT_NACK
) {
621 if (msg
->flags
& I2C_M_IGNORE_NAK
)
624 w
= omap_i2c_read_reg(dev
, OMAP_I2C_CON_REG
);
625 w
|= OMAP_I2C_CON_STP
;
626 omap_i2c_write_reg(dev
, OMAP_I2C_CON_REG
, w
);
635 * Prepare controller for a transaction and call omap_i2c_xfer_msg
636 * to do the work during IRQ processing.
639 omap_i2c_xfer(struct i2c_adapter
*adap
, struct i2c_msg msgs
[], int num
)
641 struct omap_i2c_dev
*dev
= i2c_get_adapdata(adap
);
645 omap_i2c_unidle(dev
);
647 r
= omap_i2c_wait_for_bb(dev
);
651 if (dev
->set_mpu_wkup_lat
!= NULL
)
652 dev
->set_mpu_wkup_lat(dev
->dev
, dev
->latency
);
654 for (i
= 0; i
< num
; i
++) {
655 r
= omap_i2c_xfer_msg(adap
, &msgs
[i
], (i
== (num
- 1)));
660 if (dev
->set_mpu_wkup_lat
!= NULL
)
661 dev
->set_mpu_wkup_lat(dev
->dev
, -1);
666 omap_i2c_wait_for_bb(dev
);
673 omap_i2c_func(struct i2c_adapter
*adap
)
675 return I2C_FUNC_I2C
| (I2C_FUNC_SMBUS_EMUL
& ~I2C_FUNC_SMBUS_QUICK
);
679 omap_i2c_complete_cmd(struct omap_i2c_dev
*dev
, u16 err
)
682 complete(&dev
->cmd_complete
);
686 omap_i2c_ack_stat(struct omap_i2c_dev
*dev
, u16 stat
)
688 omap_i2c_write_reg(dev
, OMAP_I2C_STAT_REG
, stat
);
691 static inline void i2c_omap_errata_i207(struct omap_i2c_dev
*dev
, u16 stat
)
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.
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
);
705 if (!(omap_i2c_read_reg(dev
, OMAP_I2C_STAT_REG
)
706 & OMAP_I2C_STAT_BB
)) {
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");
719 /* rev1 devices are apparently only on some 15xx */
720 #ifdef CONFIG_ARCH_OMAP15XX
723 omap_i2c_rev1_isr(int this_irq
, void *dev_id
)
725 struct omap_i2c_dev
*dev
= dev_id
;
731 iv
= omap_i2c_read_reg(dev
, OMAP_I2C_IV_REG
);
733 case 0x00: /* None */
735 case 0x01: /* Arbitration lost */
736 dev_err(dev
->dev
, "Arbitration lost\n");
737 omap_i2c_complete_cmd(dev
, OMAP_I2C_STAT_AL
);
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
);
743 case 0x03: /* Register access ready */
744 omap_i2c_complete_cmd(dev
, 0);
746 case 0x04: /* Receive data ready */
748 w
= omap_i2c_read_reg(dev
, OMAP_I2C_DATA_REG
);
752 *dev
->buf
++ = w
>> 8;
756 dev_err(dev
->dev
, "RRDY IRQ while no data requested\n");
758 case 0x05: /* Transmit data ready */
763 w
|= *dev
->buf
++ << 8;
766 omap_i2c_write_reg(dev
, OMAP_I2C_DATA_REG
, w
);
768 dev_err(dev
->dev
, "XRDY IRQ while no data to send\n");
777 #define omap_i2c_rev1_isr NULL
781 * OMAP3430 Errata 1.153: 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.
785 static int errata_omap3_1p153(struct omap_i2c_dev
*dev
, u16
*stat
, int *err
)
787 unsigned long timeout
= 10000;
789 while (--timeout
&& !(*stat
& OMAP_I2C_STAT_XUDF
)) {
790 if (*stat
& (OMAP_I2C_STAT_NACK
| OMAP_I2C_STAT_AL
)) {
791 omap_i2c_ack_stat(dev
, *stat
& (OMAP_I2C_STAT_XRDY
|
793 *err
|= OMAP_I2C_STAT_XUDF
;
798 *stat
= omap_i2c_read_reg(dev
, OMAP_I2C_STAT_REG
);
802 dev_err(dev
->dev
, "timeout waiting on XUDF bit\n");
810 omap_i2c_isr(int this_irq
, void *dev_id
)
812 struct omap_i2c_dev
*dev
= dev_id
;
820 bits
= omap_i2c_read_reg(dev
, OMAP_I2C_IE_REG
);
821 while ((stat
= (omap_i2c_read_reg(dev
, OMAP_I2C_STAT_REG
))) & bits
) {
822 dev_dbg(dev
->dev
, "IRQ (ISR = 0x%04x)\n", stat
);
823 if (count
++ == 100) {
824 dev_warn(dev
->dev
, "Too much work in one IRQ\n");
831 * Ack the stat in one go, but [R/X]DR and [R/X]RDY should be
832 * acked after the data operation is complete.
833 * Ref: TRM SWPU114Q Figure 18-31
835 omap_i2c_write_reg(dev
, OMAP_I2C_STAT_REG
, stat
&
836 ~(OMAP_I2C_STAT_RRDY
| OMAP_I2C_STAT_RDR
|
837 OMAP_I2C_STAT_XRDY
| OMAP_I2C_STAT_XDR
));
839 if (stat
& OMAP_I2C_STAT_NACK
) {
840 err
|= OMAP_I2C_STAT_NACK
;
841 omap_i2c_write_reg(dev
, OMAP_I2C_CON_REG
,
844 if (stat
& OMAP_I2C_STAT_AL
) {
845 dev_err(dev
->dev
, "Arbitration lost\n");
846 err
|= OMAP_I2C_STAT_AL
;
849 * ProDB0017052: Clear ARDY bit twice
851 if (stat
& (OMAP_I2C_STAT_ARDY
| OMAP_I2C_STAT_NACK
|
853 omap_i2c_ack_stat(dev
, stat
&
854 (OMAP_I2C_STAT_RRDY
| OMAP_I2C_STAT_RDR
|
855 OMAP_I2C_STAT_XRDY
| OMAP_I2C_STAT_XDR
|
856 OMAP_I2C_STAT_ARDY
));
857 omap_i2c_complete_cmd(dev
, err
);
860 if (stat
& (OMAP_I2C_STAT_RRDY
| OMAP_I2C_STAT_RDR
)) {
863 if (dev
->errata
& I2C_OMAP_ERRATA_I207
)
864 i2c_omap_errata_i207(dev
, stat
);
866 if (dev
->fifo_size
) {
867 if (stat
& OMAP_I2C_STAT_RRDY
)
868 num_bytes
= dev
->fifo_size
;
869 else /* read RXSTAT on RDR interrupt */
870 num_bytes
= (omap_i2c_read_reg(dev
,
871 OMAP_I2C_BUFSTAT_REG
)
876 w
= omap_i2c_read_reg(dev
, OMAP_I2C_DATA_REG
);
881 * Data reg in 2430, omap3 and
882 * omap4 is 8 bit wide
884 if (cpu_class_is_omap1() ||
887 *dev
->buf
++ = w
>> 8;
892 if (stat
& OMAP_I2C_STAT_RRDY
)
894 "RRDY IRQ while no data"
896 if (stat
& OMAP_I2C_STAT_RDR
)
898 "RDR IRQ while no data"
903 omap_i2c_ack_stat(dev
,
904 stat
& (OMAP_I2C_STAT_RRDY
| OMAP_I2C_STAT_RDR
));
907 if (stat
& (OMAP_I2C_STAT_XRDY
| OMAP_I2C_STAT_XDR
)) {
909 if (dev
->fifo_size
) {
910 if (stat
& OMAP_I2C_STAT_XRDY
)
911 num_bytes
= dev
->fifo_size
;
912 else /* read TXSTAT on XDR interrupt */
913 num_bytes
= omap_i2c_read_reg(dev
,
914 OMAP_I2C_BUFSTAT_REG
)
924 * Data reg in 2430, omap3 and
925 * omap4 is 8 bit wide
927 if (cpu_class_is_omap1() ||
930 w
|= *dev
->buf
++ << 8;
935 if (stat
& OMAP_I2C_STAT_XRDY
)
939 if (stat
& OMAP_I2C_STAT_XDR
)
946 if ((dev
->errata
& I2C_OMAP3_1P153
) &&
947 errata_omap3_1p153(dev
, &stat
, &err
))
950 omap_i2c_write_reg(dev
, OMAP_I2C_DATA_REG
, w
);
952 omap_i2c_ack_stat(dev
,
953 stat
& (OMAP_I2C_STAT_XRDY
| OMAP_I2C_STAT_XDR
));
956 if (stat
& OMAP_I2C_STAT_ROVR
) {
957 dev_err(dev
->dev
, "Receive overrun\n");
958 dev
->cmd_err
|= OMAP_I2C_STAT_ROVR
;
960 if (stat
& OMAP_I2C_STAT_XUDF
) {
961 dev_err(dev
->dev
, "Transmit underflow\n");
962 dev
->cmd_err
|= OMAP_I2C_STAT_XUDF
;
966 return count
? IRQ_HANDLED
: IRQ_NONE
;
969 static const struct i2c_algorithm omap_i2c_algo
= {
970 .master_xfer
= omap_i2c_xfer
,
971 .functionality
= omap_i2c_func
,
975 omap_i2c_probe(struct platform_device
*pdev
)
977 struct omap_i2c_dev
*dev
;
978 struct i2c_adapter
*adap
;
979 struct resource
*mem
, *irq
, *ioarea
;
980 struct omap_i2c_bus_platform_data
*pdata
= pdev
->dev
.platform_data
;
985 /* NOTE: driver uses the static register mapping */
986 mem
= platform_get_resource(pdev
, IORESOURCE_MEM
, 0);
988 dev_err(&pdev
->dev
, "no mem resource?\n");
991 irq
= platform_get_resource(pdev
, IORESOURCE_IRQ
, 0);
993 dev_err(&pdev
->dev
, "no irq resource?\n");
997 ioarea
= request_mem_region(mem
->start
, resource_size(mem
),
1000 dev_err(&pdev
->dev
, "I2C region already claimed\n");
1004 dev
= kzalloc(sizeof(struct omap_i2c_dev
), GFP_KERNEL
);
1007 goto err_release_region
;
1010 if (pdata
!= NULL
) {
1011 speed
= pdata
->clkrate
;
1012 dev
->set_mpu_wkup_lat
= pdata
->set_mpu_wkup_lat
;
1014 speed
= 100; /* Default speed */
1015 dev
->set_mpu_wkup_lat
= NULL
;
1020 dev
->dev
= &pdev
->dev
;
1021 dev
->irq
= irq
->start
;
1022 dev
->base
= ioremap(mem
->start
, resource_size(mem
));
1028 platform_set_drvdata(pdev
, dev
);
1030 if (cpu_is_omap7xx())
1032 else if (cpu_is_omap44xx())
1037 if (cpu_is_omap44xx())
1038 dev
->regs
= (u8
*) omap4_reg_map
;
1040 dev
->regs
= (u8
*) reg_map
;
1042 pm_runtime_enable(&pdev
->dev
);
1043 omap_i2c_unidle(dev
);
1045 dev
->rev
= omap_i2c_read_reg(dev
, OMAP_I2C_REV_REG
) & 0xff;
1047 if (dev
->rev
<= OMAP_I2C_REV_ON_3430
)
1048 dev
->errata
|= I2C_OMAP3_1P153
;
1050 if (!(cpu_class_is_omap1() || cpu_is_omap2420())) {
1053 /* Set up the fifo size - Get total size */
1054 s
= (omap_i2c_read_reg(dev
, OMAP_I2C_BUFSTAT_REG
) >> 14) & 0x3;
1055 dev
->fifo_size
= 0x8 << s
;
1058 * Set up notification threshold as half the total available
1059 * size. This is to ensure that we can handle the status on int
1060 * call back latencies.
1062 if (dev
->rev
>= OMAP_I2C_REV_ON_4430
) {
1064 dev
->b_hw
= 0; /* Disable hardware fixes */
1066 dev
->fifo_size
= (dev
->fifo_size
/ 2);
1067 dev
->b_hw
= 1; /* Enable hardware fixes */
1069 /* calculate wakeup latency constraint for MPU */
1070 if (dev
->set_mpu_wkup_lat
!= NULL
)
1071 dev
->latency
= (1000000 * dev
->fifo_size
) /
1075 /* reset ASAP, clearing any IRQs */
1078 isr
= (dev
->rev
< OMAP_I2C_REV_2
) ? omap_i2c_rev1_isr
: omap_i2c_isr
;
1079 r
= request_irq(dev
->irq
, isr
, 0, pdev
->name
, dev
);
1082 dev_err(dev
->dev
, "failure requesting irq %i\n", dev
->irq
);
1083 goto err_unuse_clocks
;
1086 dev_info(dev
->dev
, "bus %d rev%d.%d at %d kHz\n",
1087 pdev
->id
, dev
->rev
>> 4, dev
->rev
& 0xf, dev
->speed
);
1091 adap
= &dev
->adapter
;
1092 i2c_set_adapdata(adap
, dev
);
1093 adap
->owner
= THIS_MODULE
;
1094 adap
->class = I2C_CLASS_HWMON
;
1095 strlcpy(adap
->name
, "OMAP I2C adapter", sizeof(adap
->name
));
1096 adap
->algo
= &omap_i2c_algo
;
1097 adap
->dev
.parent
= &pdev
->dev
;
1099 /* i2c device drivers may be active on return from add_adapter() */
1100 adap
->nr
= pdev
->id
;
1101 r
= i2c_add_numbered_adapter(adap
);
1103 dev_err(dev
->dev
, "failure adding adapter\n");
1110 free_irq(dev
->irq
, dev
);
1112 omap_i2c_write_reg(dev
, OMAP_I2C_CON_REG
, 0);
1116 platform_set_drvdata(pdev
, NULL
);
1119 release_mem_region(mem
->start
, resource_size(mem
));
1125 omap_i2c_remove(struct platform_device
*pdev
)
1127 struct omap_i2c_dev
*dev
= platform_get_drvdata(pdev
);
1128 struct resource
*mem
;
1130 platform_set_drvdata(pdev
, NULL
);
1132 free_irq(dev
->irq
, dev
);
1133 i2c_del_adapter(&dev
->adapter
);
1134 omap_i2c_write_reg(dev
, OMAP_I2C_CON_REG
, 0);
1137 mem
= platform_get_resource(pdev
, IORESOURCE_MEM
, 0);
1138 release_mem_region(mem
->start
, resource_size(mem
));
1142 #ifdef CONFIG_SUSPEND
1143 static int omap_i2c_suspend(struct device
*dev
)
1145 if (!pm_runtime_suspended(dev
))
1146 if (dev
->bus
&& dev
->bus
->pm
&& dev
->bus
->pm
->runtime_suspend
)
1147 dev
->bus
->pm
->runtime_suspend(dev
);
1152 static int omap_i2c_resume(struct device
*dev
)
1154 if (!pm_runtime_suspended(dev
))
1155 if (dev
->bus
&& dev
->bus
->pm
&& dev
->bus
->pm
->runtime_resume
)
1156 dev
->bus
->pm
->runtime_resume(dev
);
1161 static struct dev_pm_ops omap_i2c_pm_ops
= {
1162 .suspend
= omap_i2c_suspend
,
1163 .resume
= omap_i2c_resume
,
1165 #define OMAP_I2C_PM_OPS (&omap_i2c_pm_ops)
1167 #define OMAP_I2C_PM_OPS NULL
1170 static struct platform_driver omap_i2c_driver
= {
1171 .probe
= omap_i2c_probe
,
1172 .remove
= omap_i2c_remove
,
1175 .owner
= THIS_MODULE
,
1176 .pm
= OMAP_I2C_PM_OPS
,
1180 /* I2C may be needed to bring up other drivers */
1182 omap_i2c_init_driver(void)
1184 return platform_driver_register(&omap_i2c_driver
);
1186 subsys_initcall(omap_i2c_init_driver
);
1188 static void __exit
omap_i2c_exit_driver(void)
1190 platform_driver_unregister(&omap_i2c_driver
);
1192 module_exit(omap_i2c_exit_driver
);
1194 MODULE_AUTHOR("MontaVista Software, Inc. (and others)");
1195 MODULE_DESCRIPTION("TI OMAP I2C bus adapter");
1196 MODULE_LICENSE("GPL");
1197 MODULE_ALIAS("platform:omap_i2c");