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>
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>
47 /* I2C controller revisions */
48 #define OMAP_I2C_OMAP1_REV_2 0x20
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
55 /* timeout waiting for the controller to respond */
56 #define OMAP_I2C_TIMEOUT (msecs_to_jiffies(1000))
58 /* For OMAP3 I2C_IV has changed to I2C_WE (wakeup enable) */
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
,
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 */
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 */
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 */
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)
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 */
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) */
145 /* I2C SCL time value when Master */
146 #define OMAP_I2C_SCLL_HSSCLL 8
147 #define OMAP_I2C_SCLH_HSSCLH 8
149 /* I2C System Test Register (OMAP_I2C_SYSTEST): */
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 */
161 /* OCP_SYSSTATUS bit definitions */
162 #define SYSS_RESETDONE_MASK (1 << 0)
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)
171 #define SYSC_IDLEMODE_SMART 0x2
172 #define SYSC_CLOCKACTIVITY_FCLK 0x2
174 /* Errata definitions */
175 #define I2C_OMAP_ERRATA_I207 (1 << 0)
176 #define I2C_OMAP_ERRATA_I462 (1 << 1)
178 struct omap_i2c_dev
{
180 void __iomem
*base
; /* virtual */
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
,
188 u32 speed
; /* Speed of bus in kHz */
189 u32 dtrev
; /* extra revision from DT */
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
201 unsigned b_hw
:1; /* bad h/w fixes */
202 u16 iestate
; /* Saved interrupt register */
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,
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,
259 static inline void omap_i2c_write_reg(struct omap_i2c_dev
*i2c_dev
,
262 __raw_writew(val
, i2c_dev
->base
+
263 (i2c_dev
->regs
[reg
] << i2c_dev
->reg_shift
));
266 static inline u16
omap_i2c_read_reg(struct omap_i2c_dev
*i2c_dev
, int reg
)
268 return __raw_readw(i2c_dev
->base
+
269 (i2c_dev
->regs
[reg
] << i2c_dev
->reg_shift
));
272 static int omap_i2c_init(struct omap_i2c_dev
*dev
)
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;
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
) &
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");
302 /* SYSC register is cleared by the reset; rewrite it */
303 if (dev
->rev
== OMAP_I2C_REV_ON_2430
) {
305 omap_i2c_write_reg(dev
, OMAP_I2C_SYSC_REG
,
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
));
316 omap_i2c_write_reg(dev
, OMAP_I2C_SYSC_REG
,
319 * Enabling all wakup sources to stop I2C freezing on
321 * REVISIT: Some wkup sources might not be needed.
323 dev
->westate
= OMAP_I2C_WE_ALL
;
324 omap_i2c_write_reg(dev
, OMAP_I2C_WE_REG
,
328 omap_i2c_write_reg(dev
, OMAP_I2C_CON_REG
, 0);
330 if (dev
->flags
& OMAP_I2C_FLAG_ALWAYS_ARMXOR_CLK
) {
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.
337 fclk
= clk_get(dev
->dev
, "fck");
338 fclk_rate
= clk_get_rate(fclk
);
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:
345 * XOR MHz Divider Prescaler
350 if (fclk_rate
> 12000000)
351 psc
= fclk_rate
/ 12000000;
354 if (!(dev
->flags
& OMAP_I2C_FLAG_SIMPLE_CLOCK
)) {
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.
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)
369 fclk
= clk_get(dev
->dev
, "fck");
370 fclk_rate
= clk_get_rate(fclk
) / 1000;
373 /* Compute prescaler divisor */
374 psc
= fclk_rate
/ internal_clk
;
377 /* If configured for High Speed */
378 if (dev
->speed
> 400) {
381 /* For first phase of HS mode */
382 scl
= internal_clk
/ 400;
383 fsscll
= scl
- (scl
/ 3) - 7;
384 fssclh
= (scl
/ 3) - 5;
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) {
394 scl
= internal_clk
/ dev
->speed
;
395 fsscll
= scl
- (scl
/ 3) - 7;
396 fssclh
= (scl
/ 3) - 5;
399 fsscll
= internal_clk
/ (dev
->speed
* 2) - 7;
400 fssclh
= internal_clk
/ (dev
->speed
* 2) - 5;
402 scll
= (hsscll
<< OMAP_I2C_SCLL_HSSCLL
) | fsscll
;
403 sclh
= (hssclh
<< OMAP_I2C_SCLH_HSSCLH
) | fssclh
;
405 /* Program desired operating rate */
406 fclk_rate
/= (psc
+ 1) * 1000;
409 scll
= fclk_rate
/ (dev
->speed
* 2) - 7 + psc
;
410 sclh
= fclk_rate
/ (dev
->speed
* 2) - 7 + psc
;
413 /* Setup clock prescaler to obtain approx 12MHz I2C module clock: */
414 omap_i2c_write_reg(dev
, OMAP_I2C_PSC_REG
, psc
);
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
);
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
);
427 /* Take the I2C module out of reset: */
428 omap_i2c_write_reg(dev
, OMAP_I2C_CON_REG
, OMAP_I2C_CON_EN
);
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
) {
438 dev
->scllstate
= scll
;
439 dev
->sclhstate
= sclh
;
446 * Waiting on Bus Busy
448 static int omap_i2c_wait_for_bb(struct omap_i2c_dev
*dev
)
450 unsigned long timeout
;
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");
465 * Low level master read/write transaction.
467 static int omap_i2c_xfer_msg(struct i2c_adapter
*adap
,
468 struct i2c_msg
*msg
, int stop
)
470 struct omap_i2c_dev
*dev
= i2c_get_adapdata(adap
);
471 unsigned long timeout
;
474 dev_dbg(dev
->dev
, "addr: 0x%04x, len: %d, flags: 0x%x, stop: %d\n",
475 msg
->addr
, msg
->len
, msg
->flags
, stop
);
480 omap_i2c_write_reg(dev
, OMAP_I2C_SA_REG
, msg
->addr
);
482 /* REVISIT: Could the STB bit of I2C_CON be used with probing? */
484 dev
->buf_len
= msg
->len
;
486 omap_i2c_write_reg(dev
, OMAP_I2C_CNT_REG
, dev
->buf_len
);
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
);
493 INIT_COMPLETION(dev
->cmd_complete
);
496 w
= OMAP_I2C_CON_EN
| OMAP_I2C_CON_MST
| OMAP_I2C_CON_STT
;
498 /* High speed configuration */
499 if (dev
->speed
> 400)
500 w
|= OMAP_I2C_CON_OPMODE_HS
;
502 if (msg
->flags
& I2C_M_STOP
)
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
;
509 if (!dev
->b_hw
&& stop
)
510 w
|= OMAP_I2C_CON_STP
;
512 omap_i2c_write_reg(dev
, OMAP_I2C_CON_REG
, w
);
515 * Don't write stt and stp together on some hardware.
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
);
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");
532 w
|= OMAP_I2C_CON_STP
;
533 w
&= ~OMAP_I2C_CON_STT
;
534 omap_i2c_write_reg(dev
, OMAP_I2C_CON_REG
, w
);
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.
541 timeout
= wait_for_completion_timeout(&dev
->cmd_complete
,
545 dev_err(dev
->dev
, "controller timed out\n");
550 if (likely(!dev
->cmd_err
))
553 /* We have an error */
554 if (dev
->cmd_err
& (OMAP_I2C_STAT_AL
| OMAP_I2C_STAT_ROVR
|
555 OMAP_I2C_STAT_XUDF
)) {
560 if (dev
->cmd_err
& OMAP_I2C_STAT_NACK
) {
561 if (msg
->flags
& I2C_M_IGNORE_NAK
)
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
);
575 * Prepare controller for a transaction and call omap_i2c_xfer_msg
576 * to do the work during IRQ processing.
579 omap_i2c_xfer(struct i2c_adapter
*adap
, struct i2c_msg msgs
[], int num
)
581 struct omap_i2c_dev
*dev
= i2c_get_adapdata(adap
);
585 r
= pm_runtime_get_sync(dev
->dev
);
589 r
= omap_i2c_wait_for_bb(dev
);
593 if (dev
->set_mpu_wkup_lat
!= NULL
)
594 dev
->set_mpu_wkup_lat(dev
->dev
, dev
->latency
);
596 for (i
= 0; i
< num
; i
++) {
597 r
= omap_i2c_xfer_msg(adap
, &msgs
[i
], (i
== (num
- 1)));
602 if (dev
->set_mpu_wkup_lat
!= NULL
)
603 dev
->set_mpu_wkup_lat(dev
->dev
, -1);
608 omap_i2c_wait_for_bb(dev
);
610 pm_runtime_put(dev
->dev
);
615 omap_i2c_func(struct i2c_adapter
*adap
)
617 return I2C_FUNC_I2C
| (I2C_FUNC_SMBUS_EMUL
& ~I2C_FUNC_SMBUS_QUICK
) |
618 I2C_FUNC_PROTOCOL_MANGLING
;
622 omap_i2c_complete_cmd(struct omap_i2c_dev
*dev
, u16 err
)
625 complete(&dev
->cmd_complete
);
629 omap_i2c_ack_stat(struct omap_i2c_dev
*dev
, u16 stat
)
631 omap_i2c_write_reg(dev
, OMAP_I2C_STAT_REG
, stat
);
634 static inline void i2c_omap_errata_i207(struct omap_i2c_dev
*dev
, u16 stat
)
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.
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
);
648 if (!(omap_i2c_read_reg(dev
, OMAP_I2C_STAT_REG
)
649 & OMAP_I2C_STAT_BB
)) {
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");
662 /* rev1 devices are apparently only on some 15xx */
663 #ifdef CONFIG_ARCH_OMAP15XX
666 omap_i2c_omap1_isr(int this_irq
, void *dev_id
)
668 struct omap_i2c_dev
*dev
= dev_id
;
671 if (pm_runtime_suspended(dev
->dev
))
674 iv
= omap_i2c_read_reg(dev
, OMAP_I2C_IV_REG
);
676 case 0x00: /* None */
678 case 0x01: /* Arbitration lost */
679 dev_err(dev
->dev
, "Arbitration lost\n");
680 omap_i2c_complete_cmd(dev
, OMAP_I2C_STAT_AL
);
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
);
686 case 0x03: /* Register access ready */
687 omap_i2c_complete_cmd(dev
, 0);
689 case 0x04: /* Receive data ready */
691 w
= omap_i2c_read_reg(dev
, OMAP_I2C_DATA_REG
);
695 *dev
->buf
++ = w
>> 8;
699 dev_err(dev
->dev
, "RRDY IRQ while no data requested\n");
701 case 0x05: /* Transmit data ready */
706 w
|= *dev
->buf
++ << 8;
709 omap_i2c_write_reg(dev
, OMAP_I2C_DATA_REG
, w
);
711 dev_err(dev
->dev
, "XRDY IRQ while no data to send\n");
720 #define omap_i2c_omap1_isr NULL
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.
728 static int errata_omap3_i462(struct omap_i2c_dev
*dev
, u16
*stat
, int *err
)
730 unsigned long timeout
= 10000;
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
, *stat
& (OMAP_I2C_STAT_XRDY
|
740 *stat
= omap_i2c_read_reg(dev
, OMAP_I2C_STAT_REG
);
744 dev_err(dev
->dev
, "timeout waiting on XUDF bit\n");
748 *err
|= OMAP_I2C_STAT_XUDF
;
753 omap_i2c_isr(int this_irq
, void *dev_id
)
755 struct omap_i2c_dev
*dev
= dev_id
;
760 if (pm_runtime_suspended(dev
->dev
))
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");
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
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
));
782 if (stat
& OMAP_I2C_STAT_NACK
)
783 err
|= OMAP_I2C_STAT_NACK
;
785 if (stat
& OMAP_I2C_STAT_AL
) {
786 dev_err(dev
->dev
, "Arbitration lost\n");
787 err
|= OMAP_I2C_STAT_AL
;
790 * ProDB0017052: Clear ARDY bit twice
792 if (stat
& (OMAP_I2C_STAT_ARDY
| OMAP_I2C_STAT_NACK
|
794 omap_i2c_ack_stat(dev
, stat
&
795 (OMAP_I2C_STAT_RRDY
| OMAP_I2C_STAT_RDR
|
796 OMAP_I2C_STAT_XRDY
| OMAP_I2C_STAT_XDR
|
797 OMAP_I2C_STAT_ARDY
));
798 omap_i2c_complete_cmd(dev
, err
);
801 if (stat
& (OMAP_I2C_STAT_RRDY
| OMAP_I2C_STAT_RDR
)) {
804 if (dev
->errata
& I2C_OMAP_ERRATA_I207
)
805 i2c_omap_errata_i207(dev
, stat
);
807 if (dev
->fifo_size
) {
808 if (stat
& OMAP_I2C_STAT_RRDY
)
809 num_bytes
= dev
->fifo_size
;
810 else /* read RXSTAT on RDR interrupt */
811 num_bytes
= (omap_i2c_read_reg(dev
,
812 OMAP_I2C_BUFSTAT_REG
)
817 w
= omap_i2c_read_reg(dev
, OMAP_I2C_DATA_REG
);
822 * Data reg in 2430, omap3 and
823 * omap4 is 8 bit wide
826 OMAP_I2C_FLAG_16BIT_DATA_REG
) {
828 *dev
->buf
++ = w
>> 8;
833 if (stat
& OMAP_I2C_STAT_RRDY
)
835 "RRDY IRQ while no data"
837 if (stat
& OMAP_I2C_STAT_RDR
)
839 "RDR IRQ while no data"
844 omap_i2c_ack_stat(dev
,
845 stat
& (OMAP_I2C_STAT_RRDY
| OMAP_I2C_STAT_RDR
));
848 if (stat
& (OMAP_I2C_STAT_XRDY
| OMAP_I2C_STAT_XDR
)) {
850 if (dev
->fifo_size
) {
851 if (stat
& OMAP_I2C_STAT_XRDY
)
852 num_bytes
= dev
->fifo_size
;
853 else /* read TXSTAT on XDR interrupt */
854 num_bytes
= omap_i2c_read_reg(dev
,
855 OMAP_I2C_BUFSTAT_REG
)
865 * Data reg in 2430, omap3 and
866 * omap4 is 8 bit wide
869 OMAP_I2C_FLAG_16BIT_DATA_REG
) {
871 w
|= *dev
->buf
++ << 8;
876 if (stat
& OMAP_I2C_STAT_XRDY
)
880 if (stat
& OMAP_I2C_STAT_XDR
)
887 if ((dev
->errata
& I2C_OMAP_ERRATA_I462
) &&
888 errata_omap3_i462(dev
, &stat
, &err
))
891 omap_i2c_write_reg(dev
, OMAP_I2C_DATA_REG
, w
);
893 omap_i2c_ack_stat(dev
,
894 stat
& (OMAP_I2C_STAT_XRDY
| OMAP_I2C_STAT_XDR
));
897 if (stat
& OMAP_I2C_STAT_ROVR
) {
898 dev_err(dev
->dev
, "Receive overrun\n");
899 dev
->cmd_err
|= OMAP_I2C_STAT_ROVR
;
901 if (stat
& OMAP_I2C_STAT_XUDF
) {
902 dev_err(dev
->dev
, "Transmit underflow\n");
903 dev
->cmd_err
|= OMAP_I2C_STAT_XUDF
;
907 return count
? IRQ_HANDLED
: IRQ_NONE
;
910 static const struct i2c_algorithm omap_i2c_algo
= {
911 .master_xfer
= omap_i2c_xfer
,
912 .functionality
= omap_i2c_func
,
916 static struct omap_i2c_bus_platform_data omap3_pdata
= {
917 .rev
= OMAP_I2C_IP_VERSION_1
,
918 .flags
= OMAP_I2C_FLAG_APPLY_ERRATA_I207
|
919 OMAP_I2C_FLAG_RESET_REGS_POSTIDLE
|
920 OMAP_I2C_FLAG_BUS_SHIFT_2
,
923 static struct omap_i2c_bus_platform_data omap4_pdata
= {
924 .rev
= OMAP_I2C_IP_VERSION_2
,
927 static const struct of_device_id omap_i2c_of_match
[] = {
929 .compatible
= "ti,omap4-i2c",
930 .data
= &omap4_pdata
,
933 .compatible
= "ti,omap3-i2c",
934 .data
= &omap3_pdata
,
938 MODULE_DEVICE_TABLE(of
, omap_i2c_of_match
);
942 omap_i2c_probe(struct platform_device
*pdev
)
944 struct omap_i2c_dev
*dev
;
945 struct i2c_adapter
*adap
;
946 struct resource
*mem
, *irq
, *ioarea
;
947 struct omap_i2c_bus_platform_data
*pdata
= pdev
->dev
.platform_data
;
948 struct device_node
*node
= pdev
->dev
.of_node
;
949 const struct of_device_id
*match
;
953 /* NOTE: driver uses the static register mapping */
954 mem
= platform_get_resource(pdev
, IORESOURCE_MEM
, 0);
956 dev_err(&pdev
->dev
, "no mem resource?\n");
959 irq
= platform_get_resource(pdev
, IORESOURCE_IRQ
, 0);
961 dev_err(&pdev
->dev
, "no irq resource?\n");
965 ioarea
= request_mem_region(mem
->start
, resource_size(mem
),
968 dev_err(&pdev
->dev
, "I2C region already claimed\n");
972 dev
= kzalloc(sizeof(struct omap_i2c_dev
), GFP_KERNEL
);
975 goto err_release_region
;
978 match
= of_match_device(of_match_ptr(omap_i2c_of_match
), &pdev
->dev
);
980 u32 freq
= 100000; /* default to 100000 Hz */
983 dev
->dtrev
= pdata
->rev
;
984 dev
->flags
= pdata
->flags
;
986 of_property_read_u32(node
, "clock-frequency", &freq
);
987 /* convert DT freq value in Hz into kHz for speed */
988 dev
->speed
= freq
/ 1000;
989 } else if (pdata
!= NULL
) {
990 dev
->speed
= pdata
->clkrate
;
991 dev
->flags
= pdata
->flags
;
992 dev
->set_mpu_wkup_lat
= pdata
->set_mpu_wkup_lat
;
993 dev
->dtrev
= pdata
->rev
;
996 dev
->dev
= &pdev
->dev
;
997 dev
->irq
= irq
->start
;
998 dev
->base
= ioremap(mem
->start
, resource_size(mem
));
1004 platform_set_drvdata(pdev
, dev
);
1005 init_completion(&dev
->cmd_complete
);
1007 dev
->reg_shift
= (dev
->flags
>> OMAP_I2C_FLAG_BUS_SHIFT__SHIFT
) & 3;
1009 if (dev
->dtrev
== OMAP_I2C_IP_VERSION_2
)
1010 dev
->regs
= (u8
*)reg_map_ip_v2
;
1012 dev
->regs
= (u8
*)reg_map_ip_v1
;
1014 pm_runtime_enable(dev
->dev
);
1015 r
= pm_runtime_get_sync(dev
->dev
);
1016 if (IS_ERR_VALUE(r
))
1019 dev
->rev
= omap_i2c_read_reg(dev
, OMAP_I2C_REV_REG
) & 0xff;
1023 if (dev
->flags
& OMAP_I2C_FLAG_APPLY_ERRATA_I207
)
1024 dev
->errata
|= I2C_OMAP_ERRATA_I207
;
1026 if (dev
->rev
<= OMAP_I2C_REV_ON_3430_3530
)
1027 dev
->errata
|= I2C_OMAP_ERRATA_I462
;
1029 if (!(dev
->flags
& OMAP_I2C_FLAG_NO_FIFO
)) {
1032 /* Set up the fifo size - Get total size */
1033 s
= (omap_i2c_read_reg(dev
, OMAP_I2C_BUFSTAT_REG
) >> 14) & 0x3;
1034 dev
->fifo_size
= 0x8 << s
;
1037 * Set up notification threshold as half the total available
1038 * size. This is to ensure that we can handle the status on int
1039 * call back latencies.
1042 dev
->fifo_size
= (dev
->fifo_size
/ 2);
1044 if (dev
->rev
>= OMAP_I2C_REV_ON_3630_4430
)
1045 dev
->b_hw
= 0; /* Disable hardware fixes */
1047 dev
->b_hw
= 1; /* Enable hardware fixes */
1049 /* calculate wakeup latency constraint for MPU */
1050 if (dev
->set_mpu_wkup_lat
!= NULL
)
1051 dev
->latency
= (1000000 * dev
->fifo_size
) /
1052 (1000 * dev
->speed
/ 8);
1055 /* reset ASAP, clearing any IRQs */
1058 isr
= (dev
->rev
< OMAP_I2C_OMAP1_REV_2
) ? omap_i2c_omap1_isr
:
1060 r
= request_irq(dev
->irq
, isr
, IRQF_NO_SUSPEND
, pdev
->name
, dev
);
1063 dev_err(dev
->dev
, "failure requesting irq %i\n", dev
->irq
);
1064 goto err_unuse_clocks
;
1067 dev_info(dev
->dev
, "bus %d rev%d.%d.%d at %d kHz\n", pdev
->id
,
1068 dev
->dtrev
, dev
->rev
>> 4, dev
->rev
& 0xf, dev
->speed
);
1070 adap
= &dev
->adapter
;
1071 i2c_set_adapdata(adap
, dev
);
1072 adap
->owner
= THIS_MODULE
;
1073 adap
->class = I2C_CLASS_HWMON
;
1074 strlcpy(adap
->name
, "OMAP I2C adapter", sizeof(adap
->name
));
1075 adap
->algo
= &omap_i2c_algo
;
1076 adap
->dev
.parent
= &pdev
->dev
;
1077 adap
->dev
.of_node
= pdev
->dev
.of_node
;
1079 /* i2c device drivers may be active on return from add_adapter() */
1080 adap
->nr
= pdev
->id
;
1081 r
= i2c_add_numbered_adapter(adap
);
1083 dev_err(dev
->dev
, "failure adding adapter\n");
1087 of_i2c_register_devices(adap
);
1089 pm_runtime_put(dev
->dev
);
1094 free_irq(dev
->irq
, dev
);
1096 omap_i2c_write_reg(dev
, OMAP_I2C_CON_REG
, 0);
1097 pm_runtime_put(dev
->dev
);
1099 pm_runtime_disable(&pdev
->dev
);
1101 platform_set_drvdata(pdev
, NULL
);
1104 release_mem_region(mem
->start
, resource_size(mem
));
1109 static int __devexit
omap_i2c_remove(struct platform_device
*pdev
)
1111 struct omap_i2c_dev
*dev
= platform_get_drvdata(pdev
);
1112 struct resource
*mem
;
1115 platform_set_drvdata(pdev
, NULL
);
1117 free_irq(dev
->irq
, dev
);
1118 i2c_del_adapter(&dev
->adapter
);
1119 ret
= pm_runtime_get_sync(&pdev
->dev
);
1120 if (IS_ERR_VALUE(ret
))
1123 omap_i2c_write_reg(dev
, OMAP_I2C_CON_REG
, 0);
1124 pm_runtime_put(&pdev
->dev
);
1125 pm_runtime_disable(&pdev
->dev
);
1128 mem
= platform_get_resource(pdev
, IORESOURCE_MEM
, 0);
1129 release_mem_region(mem
->start
, resource_size(mem
));
1134 #ifdef CONFIG_PM_RUNTIME
1135 static int omap_i2c_runtime_suspend(struct device
*dev
)
1137 struct platform_device
*pdev
= to_platform_device(dev
);
1138 struct omap_i2c_dev
*_dev
= platform_get_drvdata(pdev
);
1141 _dev
->iestate
= omap_i2c_read_reg(_dev
, OMAP_I2C_IE_REG
);
1143 omap_i2c_write_reg(_dev
, OMAP_I2C_IE_REG
, 0);
1145 if (_dev
->rev
< OMAP_I2C_OMAP1_REV_2
) {
1146 iv
= omap_i2c_read_reg(_dev
, OMAP_I2C_IV_REG
); /* Read clears */
1148 omap_i2c_write_reg(_dev
, OMAP_I2C_STAT_REG
, _dev
->iestate
);
1150 /* Flush posted write */
1151 omap_i2c_read_reg(_dev
, OMAP_I2C_STAT_REG
);
1157 static int omap_i2c_runtime_resume(struct device
*dev
)
1159 struct platform_device
*pdev
= to_platform_device(dev
);
1160 struct omap_i2c_dev
*_dev
= platform_get_drvdata(pdev
);
1162 if (_dev
->flags
& OMAP_I2C_FLAG_RESET_REGS_POSTIDLE
) {
1163 omap_i2c_write_reg(_dev
, OMAP_I2C_CON_REG
, 0);
1164 omap_i2c_write_reg(_dev
, OMAP_I2C_PSC_REG
, _dev
->pscstate
);
1165 omap_i2c_write_reg(_dev
, OMAP_I2C_SCLL_REG
, _dev
->scllstate
);
1166 omap_i2c_write_reg(_dev
, OMAP_I2C_SCLH_REG
, _dev
->sclhstate
);
1167 omap_i2c_write_reg(_dev
, OMAP_I2C_BUF_REG
, _dev
->bufstate
);
1168 omap_i2c_write_reg(_dev
, OMAP_I2C_SYSC_REG
, _dev
->syscstate
);
1169 omap_i2c_write_reg(_dev
, OMAP_I2C_WE_REG
, _dev
->westate
);
1170 omap_i2c_write_reg(_dev
, OMAP_I2C_CON_REG
, OMAP_I2C_CON_EN
);
1174 * Don't write to this register if the IE state is 0 as it can
1178 omap_i2c_write_reg(_dev
, OMAP_I2C_IE_REG
, _dev
->iestate
);
1182 #endif /* CONFIG_PM_RUNTIME */
1184 static struct dev_pm_ops omap_i2c_pm_ops
= {
1185 SET_RUNTIME_PM_OPS(omap_i2c_runtime_suspend
,
1186 omap_i2c_runtime_resume
, NULL
)
1188 #define OMAP_I2C_PM_OPS (&omap_i2c_pm_ops)
1190 #define OMAP_I2C_PM_OPS NULL
1191 #endif /* CONFIG_PM */
1193 static struct platform_driver omap_i2c_driver
= {
1194 .probe
= omap_i2c_probe
,
1195 .remove
= __devexit_p(omap_i2c_remove
),
1198 .owner
= THIS_MODULE
,
1199 .pm
= OMAP_I2C_PM_OPS
,
1200 .of_match_table
= of_match_ptr(omap_i2c_of_match
),
1204 /* I2C may be needed to bring up other drivers */
1206 omap_i2c_init_driver(void)
1208 return platform_driver_register(&omap_i2c_driver
);
1210 subsys_initcall(omap_i2c_init_driver
);
1212 static void __exit
omap_i2c_exit_driver(void)
1214 platform_driver_unregister(&omap_i2c_driver
);
1216 module_exit(omap_i2c_exit_driver
);
1218 MODULE_AUTHOR("MontaVista Software, Inc. (and others)");
1219 MODULE_DESCRIPTION("TI OMAP I2C bus adapter");
1220 MODULE_LICENSE("GPL");
1221 MODULE_ALIAS("platform:omap_i2c");