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_TEN)
503 w |= OMAP_I2C_CON_XA;
504 if (!(msg->flags & I2C_M_RD))
505 w |= OMAP_I2C_CON_TRX;
507 if (!dev->b_hw && stop)
508 w |= OMAP_I2C_CON_STP;
510 omap_i2c_write_reg(dev, OMAP_I2C_CON_REG, w);
513 * Don't write stt and stp together on some hardware.
515 if (dev->b_hw && stop) {
516 unsigned long delay = jiffies + OMAP_I2C_TIMEOUT;
517 u16 con = omap_i2c_read_reg(dev, OMAP_I2C_CON_REG);
518 while (con & OMAP_I2C_CON_STT) {
519 con = omap_i2c_read_reg(dev, OMAP_I2C_CON_REG);
521 /* Let the user know if i2c is in a bad state */
522 if (time_after(jiffies, delay)) {
523 dev_err(dev->dev, "controller timed out "
524 "waiting for start condition to finish\n");
530 w |= OMAP_I2C_CON_STP;
531 w &= ~OMAP_I2C_CON_STT;
532 omap_i2c_write_reg(dev, OMAP_I2C_CON_REG, w);
536 * REVISIT: We should abort the transfer on signals, but the bus goes
537 * into arbitration and we're currently unable to recover from it.
539 timeout = wait_for_completion_timeout(&dev->cmd_complete,
543 dev_err(dev->dev, "controller timed out\n");
548 if (likely(!dev->cmd_err))
551 /* We have an error */
552 if (dev->cmd_err & (OMAP_I2C_STAT_AL | OMAP_I2C_STAT_ROVR |
553 OMAP_I2C_STAT_XUDF)) {
558 if (dev->cmd_err & OMAP_I2C_STAT_NACK) {
559 if (msg->flags & I2C_M_IGNORE_NAK)
562 w = omap_i2c_read_reg(dev, OMAP_I2C_CON_REG);
563 w |= OMAP_I2C_CON_STP;
564 omap_i2c_write_reg(dev, OMAP_I2C_CON_REG, w);
573 * Prepare controller for a transaction and call omap_i2c_xfer_msg
574 * to do the work during IRQ processing.
577 omap_i2c_xfer(struct i2c_adapter *adap, struct i2c_msg msgs[], int num)
579 struct omap_i2c_dev *dev = i2c_get_adapdata(adap);
583 r = pm_runtime_get_sync(dev->dev);
587 r = omap_i2c_wait_for_bb(dev);
591 if (dev->set_mpu_wkup_lat != NULL)
592 dev->set_mpu_wkup_lat(dev->dev, dev->latency);
594 for (i = 0; i < num; i++) {
595 r = omap_i2c_xfer_msg(adap, &msgs[i], (i == (num - 1)));
600 if (dev->set_mpu_wkup_lat != NULL)
601 dev->set_mpu_wkup_lat(dev->dev, -1);
606 omap_i2c_wait_for_bb(dev);
608 pm_runtime_put(dev->dev);
613 omap_i2c_func(struct i2c_adapter *adap)
615 return I2C_FUNC_I2C | (I2C_FUNC_SMBUS_EMUL & ~I2C_FUNC_SMBUS_QUICK);
619 omap_i2c_complete_cmd(struct omap_i2c_dev *dev, u16 err)
622 complete(&dev->cmd_complete);
626 omap_i2c_ack_stat(struct omap_i2c_dev *dev, u16 stat)
628 omap_i2c_write_reg(dev, OMAP_I2C_STAT_REG, stat);
631 static inline void i2c_omap_errata_i207(struct omap_i2c_dev *dev, u16 stat)
634 * I2C Errata(Errata Nos. OMAP2: 1.67, OMAP3: 1.8)
635 * Not applicable for OMAP4.
636 * Under certain rare conditions, RDR could be set again
637 * when the bus is busy, then ignore the interrupt and
638 * clear the interrupt.
640 if (stat & OMAP_I2C_STAT_RDR) {
641 /* Step 1: If RDR is set, clear it */
642 omap_i2c_ack_stat(dev, OMAP_I2C_STAT_RDR);
645 if (!(omap_i2c_read_reg(dev, OMAP_I2C_STAT_REG)
646 & OMAP_I2C_STAT_BB)) {
649 if (omap_i2c_read_reg(dev, OMAP_I2C_STAT_REG)
650 & OMAP_I2C_STAT_RDR) {
651 omap_i2c_ack_stat(dev, OMAP_I2C_STAT_RDR);
652 dev_dbg(dev->dev, "RDR when bus is busy.\n");
659 /* rev1 devices are apparently only on some 15xx */
660 #ifdef CONFIG_ARCH_OMAP15XX
663 omap_i2c_omap1_isr(int this_irq, void *dev_id)
665 struct omap_i2c_dev *dev = dev_id;
668 if (pm_runtime_suspended(dev->dev))
671 iv = omap_i2c_read_reg(dev, OMAP_I2C_IV_REG);
673 case 0x00: /* None */
675 case 0x01: /* Arbitration lost */
676 dev_err(dev->dev, "Arbitration lost\n");
677 omap_i2c_complete_cmd(dev, OMAP_I2C_STAT_AL);
679 case 0x02: /* No acknowledgement */
680 omap_i2c_complete_cmd(dev, OMAP_I2C_STAT_NACK);
681 omap_i2c_write_reg(dev, OMAP_I2C_CON_REG, OMAP_I2C_CON_STP);
683 case 0x03: /* Register access ready */
684 omap_i2c_complete_cmd(dev, 0);
686 case 0x04: /* Receive data ready */
688 w = omap_i2c_read_reg(dev, OMAP_I2C_DATA_REG);
692 *dev->buf++ = w >> 8;
696 dev_err(dev->dev, "RRDY IRQ while no data requested\n");
698 case 0x05: /* Transmit data ready */
703 w |= *dev->buf++ << 8;
706 omap_i2c_write_reg(dev, OMAP_I2C_DATA_REG, w);
708 dev_err(dev->dev, "XRDY IRQ while no data to send\n");
717 #define omap_i2c_omap1_isr NULL
721 * OMAP3430 Errata i462: When an XRDY/XDR is hit, wait for XUDF before writing
722 * data to DATA_REG. Otherwise some data bytes can be lost while transferring
723 * them from the memory to the I2C interface.
725 static int errata_omap3_i462(struct omap_i2c_dev *dev, u16 *stat, int *err)
727 unsigned long timeout = 10000;
729 while (--timeout && !(*stat & OMAP_I2C_STAT_XUDF)) {
730 if (*stat & (OMAP_I2C_STAT_NACK | OMAP_I2C_STAT_AL)) {
731 omap_i2c_ack_stat(dev, *stat & (OMAP_I2C_STAT_XRDY |
737 *stat = omap_i2c_read_reg(dev, OMAP_I2C_STAT_REG);
741 dev_err(dev->dev, "timeout waiting on XUDF bit\n");
745 *err |= OMAP_I2C_STAT_XUDF;
750 omap_i2c_isr(int this_irq, void *dev_id)
752 struct omap_i2c_dev *dev = dev_id;
757 if (pm_runtime_suspended(dev->dev))
760 bits = omap_i2c_read_reg(dev, OMAP_I2C_IE_REG);
761 while ((stat = (omap_i2c_read_reg(dev, OMAP_I2C_STAT_REG))) & bits) {
762 dev_dbg(dev->dev, "IRQ (ISR = 0x%04x)\n", stat);
763 if (count++ == 100) {
764 dev_warn(dev->dev, "Too much work in one IRQ\n");
771 * Ack the stat in one go, but [R/X]DR and [R/X]RDY should be
772 * acked after the data operation is complete.
773 * Ref: TRM SWPU114Q Figure 18-31
775 omap_i2c_write_reg(dev, OMAP_I2C_STAT_REG, stat &
776 ~(OMAP_I2C_STAT_RRDY | OMAP_I2C_STAT_RDR |
777 OMAP_I2C_STAT_XRDY | OMAP_I2C_STAT_XDR));
779 if (stat & OMAP_I2C_STAT_NACK)
780 err |= OMAP_I2C_STAT_NACK;
782 if (stat & OMAP_I2C_STAT_AL) {
783 dev_err(dev->dev, "Arbitration lost\n");
784 err |= OMAP_I2C_STAT_AL;
787 * ProDB0017052: Clear ARDY bit twice
789 if (stat & (OMAP_I2C_STAT_ARDY | OMAP_I2C_STAT_NACK |
791 omap_i2c_ack_stat(dev, stat &
792 (OMAP_I2C_STAT_RRDY | OMAP_I2C_STAT_RDR |
793 OMAP_I2C_STAT_XRDY | OMAP_I2C_STAT_XDR |
794 OMAP_I2C_STAT_ARDY));
795 omap_i2c_complete_cmd(dev, err);
798 if (stat & (OMAP_I2C_STAT_RRDY | OMAP_I2C_STAT_RDR)) {
801 if (dev->errata & I2C_OMAP_ERRATA_I207)
802 i2c_omap_errata_i207(dev, stat);
804 if (dev->fifo_size) {
805 if (stat & OMAP_I2C_STAT_RRDY)
806 num_bytes = dev->fifo_size;
807 else /* read RXSTAT on RDR interrupt */
808 num_bytes = (omap_i2c_read_reg(dev,
809 OMAP_I2C_BUFSTAT_REG)
814 w = omap_i2c_read_reg(dev, OMAP_I2C_DATA_REG);
819 * Data reg in 2430, omap3 and
820 * omap4 is 8 bit wide
823 OMAP_I2C_FLAG_16BIT_DATA_REG) {
825 *dev->buf++ = w >> 8;
830 if (stat & OMAP_I2C_STAT_RRDY)
832 "RRDY IRQ while no data"
834 if (stat & OMAP_I2C_STAT_RDR)
836 "RDR IRQ while no data"
841 omap_i2c_ack_stat(dev,
842 stat & (OMAP_I2C_STAT_RRDY | OMAP_I2C_STAT_RDR));
845 if (stat & (OMAP_I2C_STAT_XRDY | OMAP_I2C_STAT_XDR)) {
847 if (dev->fifo_size) {
848 if (stat & OMAP_I2C_STAT_XRDY)
849 num_bytes = dev->fifo_size;
850 else /* read TXSTAT on XDR interrupt */
851 num_bytes = omap_i2c_read_reg(dev,
852 OMAP_I2C_BUFSTAT_REG)
862 * Data reg in 2430, omap3 and
863 * omap4 is 8 bit wide
866 OMAP_I2C_FLAG_16BIT_DATA_REG) {
868 w |= *dev->buf++ << 8;
873 if (stat & OMAP_I2C_STAT_XRDY)
877 if (stat & OMAP_I2C_STAT_XDR)
884 if ((dev->errata & I2C_OMAP_ERRATA_I462) &&
885 errata_omap3_i462(dev, &stat, &err))
888 omap_i2c_write_reg(dev, OMAP_I2C_DATA_REG, w);
890 omap_i2c_ack_stat(dev,
891 stat & (OMAP_I2C_STAT_XRDY | OMAP_I2C_STAT_XDR));
894 if (stat & OMAP_I2C_STAT_ROVR) {
895 dev_err(dev->dev, "Receive overrun\n");
896 dev->cmd_err |= OMAP_I2C_STAT_ROVR;
898 if (stat & OMAP_I2C_STAT_XUDF) {
899 dev_err(dev->dev, "Transmit underflow\n");
900 dev->cmd_err |= OMAP_I2C_STAT_XUDF;
904 return count ? IRQ_HANDLED : IRQ_NONE;
907 static const struct i2c_algorithm omap_i2c_algo = {
908 .master_xfer = omap_i2c_xfer,
909 .functionality = omap_i2c_func,
913 static struct omap_i2c_bus_platform_data omap3_pdata = {
914 .rev = OMAP_I2C_IP_VERSION_1,
915 .flags = OMAP_I2C_FLAG_APPLY_ERRATA_I207 |
916 OMAP_I2C_FLAG_RESET_REGS_POSTIDLE |
917 OMAP_I2C_FLAG_BUS_SHIFT_2,
920 static struct omap_i2c_bus_platform_data omap4_pdata = {
921 .rev = OMAP_I2C_IP_VERSION_2,
924 static const struct of_device_id omap_i2c_of_match[] = {
926 .compatible = "ti,omap4-i2c",
927 .data = &omap4_pdata,
930 .compatible = "ti,omap3-i2c",
931 .data = &omap3_pdata,
935 MODULE_DEVICE_TABLE(of, omap_i2c_of_match);
939 omap_i2c_probe(struct platform_device *pdev)
941 struct omap_i2c_dev *dev;
942 struct i2c_adapter *adap;
943 struct resource *mem, *irq, *ioarea;
944 struct omap_i2c_bus_platform_data *pdata = pdev->dev.platform_data;
945 struct device_node *node = pdev->dev.of_node;
946 const struct of_device_id *match;
950 /* NOTE: driver uses the static register mapping */
951 mem = platform_get_resource(pdev, IORESOURCE_MEM, 0);
953 dev_err(&pdev->dev, "no mem resource?\n");
956 irq = platform_get_resource(pdev, IORESOURCE_IRQ, 0);
958 dev_err(&pdev->dev, "no irq resource?\n");
962 ioarea = request_mem_region(mem->start, resource_size(mem),
965 dev_err(&pdev->dev, "I2C region already claimed\n");
969 dev = kzalloc(sizeof(struct omap_i2c_dev), GFP_KERNEL);
972 goto err_release_region;
975 match = of_match_device(of_match_ptr(omap_i2c_of_match), &pdev->dev);
977 u32 freq = 100000; /* default to 100000 Hz */
980 dev->dtrev = pdata->rev;
981 dev->flags = pdata->flags;
983 of_property_read_u32(node, "clock-frequency", &freq);
984 /* convert DT freq value in Hz into kHz for speed */
985 dev->speed = freq / 1000;
986 } else if (pdata != NULL) {
987 dev->speed = pdata->clkrate;
988 dev->flags = pdata->flags;
989 dev->set_mpu_wkup_lat = pdata->set_mpu_wkup_lat;
990 dev->dtrev = pdata->rev;
993 dev->dev = &pdev->dev;
994 dev->irq = irq->start;
995 dev->base = ioremap(mem->start, resource_size(mem));
1001 platform_set_drvdata(pdev, dev);
1002 init_completion(&dev->cmd_complete);
1004 dev->reg_shift = (dev->flags >> OMAP_I2C_FLAG_BUS_SHIFT__SHIFT) & 3;
1006 if (dev->dtrev == OMAP_I2C_IP_VERSION_2)
1007 dev->regs = (u8 *)reg_map_ip_v2;
1009 dev->regs = (u8 *)reg_map_ip_v1;
1011 pm_runtime_enable(dev->dev);
1012 r = pm_runtime_get_sync(dev->dev);
1013 if (IS_ERR_VALUE(r))
1016 dev->rev = omap_i2c_read_reg(dev, OMAP_I2C_REV_REG) & 0xff;
1020 if (dev->flags & OMAP_I2C_FLAG_APPLY_ERRATA_I207)
1021 dev->errata |= I2C_OMAP_ERRATA_I207;
1023 if (dev->rev <= OMAP_I2C_REV_ON_3430_3530)
1024 dev->errata |= I2C_OMAP_ERRATA_I462;
1026 if (!(dev->flags & OMAP_I2C_FLAG_NO_FIFO)) {
1029 /* Set up the fifo size - Get total size */
1030 s = (omap_i2c_read_reg(dev, OMAP_I2C_BUFSTAT_REG) >> 14) & 0x3;
1031 dev->fifo_size = 0x8 << s;
1034 * Set up notification threshold as half the total available
1035 * size. This is to ensure that we can handle the status on int
1036 * call back latencies.
1039 dev->fifo_size = (dev->fifo_size / 2);
1041 if (dev->rev >= OMAP_I2C_REV_ON_3630_4430)
1042 dev->b_hw = 0; /* Disable hardware fixes */
1044 dev->b_hw = 1; /* Enable hardware fixes */
1046 /* calculate wakeup latency constraint for MPU */
1047 if (dev->set_mpu_wkup_lat != NULL)
1048 dev->latency = (1000000 * dev->fifo_size) /
1049 (1000 * dev->speed / 8);
1052 /* reset ASAP, clearing any IRQs */
1055 isr = (dev->rev < OMAP_I2C_OMAP1_REV_2) ? omap_i2c_omap1_isr :
1057 r = request_irq(dev->irq, isr, IRQF_NO_SUSPEND, pdev->name, dev);
1060 dev_err(dev->dev, "failure requesting irq %i\n", dev->irq);
1061 goto err_unuse_clocks;
1064 dev_info(dev->dev, "bus %d rev%d.%d.%d at %d kHz\n", pdev->id,
1065 dev->dtrev, dev->rev >> 4, dev->rev & 0xf, dev->speed);
1067 adap = &dev->adapter;
1068 i2c_set_adapdata(adap, dev);
1069 adap->owner = THIS_MODULE;
1070 adap->class = I2C_CLASS_HWMON;
1071 strlcpy(adap->name, "OMAP I2C adapter", sizeof(adap->name));
1072 adap->algo = &omap_i2c_algo;
1073 adap->dev.parent = &pdev->dev;
1074 adap->dev.of_node = pdev->dev.of_node;
1076 /* i2c device drivers may be active on return from add_adapter() */
1077 adap->nr = pdev->id;
1078 r = i2c_add_numbered_adapter(adap);
1080 dev_err(dev->dev, "failure adding adapter\n");
1084 of_i2c_register_devices(adap);
1086 pm_runtime_put(dev->dev);
1091 free_irq(dev->irq, dev);
1093 omap_i2c_write_reg(dev, OMAP_I2C_CON_REG, 0);
1094 pm_runtime_put(dev->dev);
1096 pm_runtime_disable(&pdev->dev);
1098 platform_set_drvdata(pdev, NULL);
1101 release_mem_region(mem->start, resource_size(mem));
1106 static int __devexit omap_i2c_remove(struct platform_device *pdev)
1108 struct omap_i2c_dev *dev = platform_get_drvdata(pdev);
1109 struct resource *mem;
1112 platform_set_drvdata(pdev, NULL);
1114 free_irq(dev->irq, dev);
1115 i2c_del_adapter(&dev->adapter);
1116 ret = pm_runtime_get_sync(&pdev->dev);
1117 if (IS_ERR_VALUE(ret))
1120 omap_i2c_write_reg(dev, OMAP_I2C_CON_REG, 0);
1121 pm_runtime_put(&pdev->dev);
1122 pm_runtime_disable(&pdev->dev);
1125 mem = platform_get_resource(pdev, IORESOURCE_MEM, 0);
1126 release_mem_region(mem->start, resource_size(mem));
1131 #ifdef CONFIG_PM_RUNTIME
1132 static int omap_i2c_runtime_suspend(struct device *dev)
1134 struct platform_device *pdev = to_platform_device(dev);
1135 struct omap_i2c_dev *_dev = platform_get_drvdata(pdev);
1138 _dev->iestate = omap_i2c_read_reg(_dev, OMAP_I2C_IE_REG);
1140 omap_i2c_write_reg(_dev, OMAP_I2C_IE_REG, 0);
1142 if (_dev->rev < OMAP_I2C_OMAP1_REV_2) {
1143 iv = omap_i2c_read_reg(_dev, OMAP_I2C_IV_REG); /* Read clears */
1145 omap_i2c_write_reg(_dev, OMAP_I2C_STAT_REG, _dev->iestate);
1147 /* Flush posted write */
1148 omap_i2c_read_reg(_dev, OMAP_I2C_STAT_REG);
1154 static int omap_i2c_runtime_resume(struct device *dev)
1156 struct platform_device *pdev = to_platform_device(dev);
1157 struct omap_i2c_dev *_dev = platform_get_drvdata(pdev);
1159 if (_dev->flags & OMAP_I2C_FLAG_RESET_REGS_POSTIDLE) {
1160 omap_i2c_write_reg(_dev, OMAP_I2C_CON_REG, 0);
1161 omap_i2c_write_reg(_dev, OMAP_I2C_PSC_REG, _dev->pscstate);
1162 omap_i2c_write_reg(_dev, OMAP_I2C_SCLL_REG, _dev->scllstate);
1163 omap_i2c_write_reg(_dev, OMAP_I2C_SCLH_REG, _dev->sclhstate);
1164 omap_i2c_write_reg(_dev, OMAP_I2C_BUF_REG, _dev->bufstate);
1165 omap_i2c_write_reg(_dev, OMAP_I2C_SYSC_REG, _dev->syscstate);
1166 omap_i2c_write_reg(_dev, OMAP_I2C_WE_REG, _dev->westate);
1167 omap_i2c_write_reg(_dev, OMAP_I2C_CON_REG, OMAP_I2C_CON_EN);
1171 * Don't write to this register if the IE state is 0 as it can
1175 omap_i2c_write_reg(_dev, OMAP_I2C_IE_REG, _dev->iestate);
1179 #endif /* CONFIG_PM_RUNTIME */
1181 static struct dev_pm_ops omap_i2c_pm_ops = {
1182 SET_RUNTIME_PM_OPS(omap_i2c_runtime_suspend,
1183 omap_i2c_runtime_resume, NULL)
1185 #define OMAP_I2C_PM_OPS (&omap_i2c_pm_ops)
1187 #define OMAP_I2C_PM_OPS NULL
1188 #endif /* CONFIG_PM */
1190 static struct platform_driver omap_i2c_driver = {
1191 .probe = omap_i2c_probe,
1192 .remove = __devexit_p(omap_i2c_remove),
1195 .owner = THIS_MODULE,
1196 .pm = OMAP_I2C_PM_OPS,
1197 .of_match_table = of_match_ptr(omap_i2c_of_match),
1201 /* I2C may be needed to bring up other drivers */
1203 omap_i2c_init_driver(void)
1205 return platform_driver_register(&omap_i2c_driver);
1207 subsys_initcall(omap_i2c_init_driver);
1209 static void __exit omap_i2c_exit_driver(void)
1211 platform_driver_unregister(&omap_i2c_driver);
1213 module_exit(omap_i2c_exit_driver);
1215 MODULE_AUTHOR("MontaVista Software, Inc. (and others)");
1216 MODULE_DESCRIPTION("TI OMAP I2C bus adapter");
1217 MODULE_LICENSE("GPL");
1218 MODULE_ALIAS("platform:omap_i2c");