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@nokia.com>
13 * Syed Khasim <x0khasim@ti.com>
15 * This program is free software; you can redistribute it and/or modify
16 * it under the terms of the GNU General Public License as published by
17 * the Free Software Foundation; either version 2 of the License, or
18 * (at your option) any later version.
20 * This program is distributed in the hope that it will be useful,
21 * but WITHOUT ANY WARRANTY; without even the implied warranty of
22 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
23 * GNU General Public License for more details.
25 * You should have received a copy of the GNU General Public License
26 * along with this program; if not, write to the Free Software
27 * Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
30 #include <linux/module.h>
31 #include <linux/delay.h>
32 #include <linux/i2c.h>
33 #include <linux/err.h>
34 #include <linux/interrupt.h>
35 #include <linux/completion.h>
36 #include <linux/platform_device.h>
37 #include <linux/clk.h>
41 /* Hack to enable zero length transfers and smbus quick until clean fix
45 /* timeout waiting for the controller to respond */
46 #define OMAP_I2C_TIMEOUT (msecs_to_jiffies(1000))
48 #define OMAP_I2C_REV_REG 0x00
49 #define OMAP_I2C_IE_REG 0x04
50 #define OMAP_I2C_STAT_REG 0x08
51 #define OMAP_I2C_IV_REG 0x0c
52 #define OMAP_I2C_SYSS_REG 0x10
53 #define OMAP_I2C_BUF_REG 0x14
54 #define OMAP_I2C_CNT_REG 0x18
55 #define OMAP_I2C_DATA_REG 0x1c
56 #define OMAP_I2C_SYSC_REG 0x20
57 #define OMAP_I2C_CON_REG 0x24
58 #define OMAP_I2C_OA_REG 0x28
59 #define OMAP_I2C_SA_REG 0x2c
60 #define OMAP_I2C_PSC_REG 0x30
61 #define OMAP_I2C_SCLL_REG 0x34
62 #define OMAP_I2C_SCLH_REG 0x38
63 #define OMAP_I2C_SYSTEST_REG 0x3c
64 #define OMAP_I2C_BUFSTAT_REG 0x40
66 /* I2C Interrupt Enable Register (OMAP_I2C_IE): */
67 #define OMAP_I2C_IE_XDR (1 << 14) /* TX Buffer draining int enable */
68 #define OMAP_I2C_IE_RDR (1 << 13) /* RX Buffer draining int enable */
69 #define OMAP_I2C_IE_XRDY (1 << 4) /* TX data ready int enable */
70 #define OMAP_I2C_IE_RRDY (1 << 3) /* RX data ready int enable */
71 #define OMAP_I2C_IE_ARDY (1 << 2) /* Access ready int enable */
72 #define OMAP_I2C_IE_NACK (1 << 1) /* No ack interrupt enable */
73 #define OMAP_I2C_IE_AL (1 << 0) /* Arbitration lost int ena */
75 /* I2C Status Register (OMAP_I2C_STAT): */
76 #define OMAP_I2C_STAT_XDR (1 << 14) /* TX Buffer draining */
77 #define OMAP_I2C_STAT_RDR (1 << 13) /* RX Buffer draining */
78 #define OMAP_I2C_STAT_BB (1 << 12) /* Bus busy */
79 #define OMAP_I2C_STAT_ROVR (1 << 11) /* Receive overrun */
80 #define OMAP_I2C_STAT_XUDF (1 << 10) /* Transmit underflow */
81 #define OMAP_I2C_STAT_AAS (1 << 9) /* Address as slave */
82 #define OMAP_I2C_STAT_AD0 (1 << 8) /* Address zero */
83 #define OMAP_I2C_STAT_XRDY (1 << 4) /* Transmit data ready */
84 #define OMAP_I2C_STAT_RRDY (1 << 3) /* Receive data ready */
85 #define OMAP_I2C_STAT_ARDY (1 << 2) /* Register access ready */
86 #define OMAP_I2C_STAT_NACK (1 << 1) /* No ack interrupt enable */
87 #define OMAP_I2C_STAT_AL (1 << 0) /* Arbitration lost int ena */
89 /* I2C Buffer Configuration Register (OMAP_I2C_BUF): */
90 #define OMAP_I2C_BUF_RDMA_EN (1 << 15) /* RX DMA channel enable */
91 #define OMAP_I2C_BUF_RXFIF_CLR (1 << 14) /* RX FIFO Clear */
92 #define OMAP_I2C_BUF_XDMA_EN (1 << 7) /* TX DMA channel enable */
93 #define OMAP_I2C_BUF_TXFIF_CLR (1 << 6) /* TX FIFO Clear */
95 /* I2C Configuration Register (OMAP_I2C_CON): */
96 #define OMAP_I2C_CON_EN (1 << 15) /* I2C module enable */
97 #define OMAP_I2C_CON_BE (1 << 14) /* Big endian mode */
98 #define OMAP_I2C_CON_OPMODE_HS (1 << 12) /* High Speed support */
99 #define OMAP_I2C_CON_STB (1 << 11) /* Start byte mode (master) */
100 #define OMAP_I2C_CON_MST (1 << 10) /* Master/slave mode */
101 #define OMAP_I2C_CON_TRX (1 << 9) /* TX/RX mode (master only) */
102 #define OMAP_I2C_CON_XA (1 << 8) /* Expand address */
103 #define OMAP_I2C_CON_RM (1 << 2) /* Repeat mode (master only) */
104 #define OMAP_I2C_CON_STP (1 << 1) /* Stop cond (master only) */
105 #define OMAP_I2C_CON_STT (1 << 0) /* Start condition (master) */
107 /* I2C SCL time value when Master */
108 #define OMAP_I2C_SCLL_HSSCLL 8
109 #define OMAP_I2C_SCLH_HSSCLH 8
111 /* I2C System Test Register (OMAP_I2C_SYSTEST): */
113 #define OMAP_I2C_SYSTEST_ST_EN (1 << 15) /* System test enable */
114 #define OMAP_I2C_SYSTEST_FREE (1 << 14) /* Free running mode */
115 #define OMAP_I2C_SYSTEST_TMODE_MASK (3 << 12) /* Test mode select */
116 #define OMAP_I2C_SYSTEST_TMODE_SHIFT (12) /* Test mode select */
117 #define OMAP_I2C_SYSTEST_SCL_I (1 << 3) /* SCL line sense in */
118 #define OMAP_I2C_SYSTEST_SCL_O (1 << 2) /* SCL line drive out */
119 #define OMAP_I2C_SYSTEST_SDA_I (1 << 1) /* SDA line sense in */
120 #define OMAP_I2C_SYSTEST_SDA_O (1 << 0) /* SDA line drive out */
123 /* I2C System Status register (OMAP_I2C_SYSS): */
124 #define OMAP_I2C_SYSS_RDONE (1 << 0) /* Reset Done */
126 /* I2C System Configuration Register (OMAP_I2C_SYSC): */
127 #define OMAP_I2C_SYSC_SRST (1 << 1) /* Soft Reset */
129 struct omap_i2c_dev {
131 void __iomem *base; /* virtual */
133 struct clk *iclk; /* Interface clock */
134 struct clk *fclk; /* Functional clock */
135 struct completion cmd_complete;
136 struct resource *ioarea;
137 u32 speed; /* Speed of bus in Khz */
141 struct i2c_adapter adapter;
142 u8 fifo_size; /* use as flag and value
143 * fifo_size==0 implies no fifo
144 * if set, should be trsh+1
147 unsigned b_hw:1; /* bad h/w fixes */
150 static inline void omap_i2c_write_reg(struct omap_i2c_dev *i2c_dev,
153 __raw_writew(val, i2c_dev->base + reg);
156 static inline u16 omap_i2c_read_reg(struct omap_i2c_dev *i2c_dev, int reg)
158 return __raw_readw(i2c_dev->base + reg);
161 static int omap_i2c_get_clocks(struct omap_i2c_dev *dev)
163 if (cpu_is_omap16xx() || cpu_class_is_omap2()) {
164 dev->iclk = clk_get(dev->dev, "i2c_ick");
165 if (IS_ERR(dev->iclk)) {
170 /* For I2C operations on 2430 we need 96Mhz clock */
171 if (cpu_is_omap2430()) {
172 dev->fclk = clk_get(dev->dev, "i2chs_fck");
173 if (IS_ERR(dev->fclk)) {
174 if (dev->iclk != NULL) {
182 dev->fclk = clk_get(dev->dev, "i2c_fck");
183 if (IS_ERR(dev->fclk)) {
184 if (dev->iclk != NULL) {
195 static void omap_i2c_put_clocks(struct omap_i2c_dev *dev)
199 if (dev->iclk != NULL) {
205 static void omap_i2c_enable_clocks(struct omap_i2c_dev *dev)
207 if (dev->iclk != NULL)
208 clk_enable(dev->iclk);
209 clk_enable(dev->fclk);
212 static void omap_i2c_disable_clocks(struct omap_i2c_dev *dev)
214 if (dev->iclk != NULL)
215 clk_disable(dev->iclk);
216 clk_disable(dev->fclk);
219 static int omap_i2c_init(struct omap_i2c_dev *dev)
221 u16 psc = 0, scll = 0, sclh = 0;
222 u16 fsscll = 0, fssclh = 0, hsscll = 0, hssclh = 0;
223 unsigned long fclk_rate = 12000000;
224 unsigned long timeout;
225 unsigned long internal_clk = 0;
228 omap_i2c_write_reg(dev, OMAP_I2C_SYSC_REG, OMAP_I2C_SYSC_SRST);
229 /* For some reason we need to set the EN bit before the
230 * reset done bit gets set. */
231 timeout = jiffies + OMAP_I2C_TIMEOUT;
232 omap_i2c_write_reg(dev, OMAP_I2C_CON_REG, OMAP_I2C_CON_EN);
233 while (!(omap_i2c_read_reg(dev, OMAP_I2C_SYSS_REG) &
234 OMAP_I2C_SYSS_RDONE)) {
235 if (time_after(jiffies, timeout)) {
236 dev_warn(dev->dev, "timeout waiting "
237 "for controller reset\n");
243 omap_i2c_write_reg(dev, OMAP_I2C_CON_REG, 0);
245 if (cpu_class_is_omap1()) {
246 struct clk *armxor_ck;
248 armxor_ck = clk_get(NULL, "armxor_ck");
249 if (IS_ERR(armxor_ck))
250 dev_warn(dev->dev, "Could not get armxor_ck\n");
252 fclk_rate = clk_get_rate(armxor_ck);
255 /* TRM for 5912 says the I2C clock must be prescaled to be
256 * between 7 - 12 MHz. The XOR input clock is typically
257 * 12, 13 or 19.2 MHz. So we should have code that produces:
259 * XOR MHz Divider Prescaler
264 if (fclk_rate > 12000000)
265 psc = fclk_rate / 12000000;
268 if (cpu_is_omap2430() || cpu_is_omap34xx()) {
270 /* HSI2C controller internal clk rate should be 19.2 Mhz */
271 internal_clk = 19200;
272 fclk_rate = clk_get_rate(dev->fclk) / 1000;
274 /* Compute prescaler divisor */
275 psc = fclk_rate / internal_clk;
278 /* If configured for High Speed */
279 if (dev->speed > 400) {
280 /* For first phase of HS mode */
281 fsscll = internal_clk / (400 * 2) - 6;
282 fssclh = internal_clk / (400 * 2) - 6;
284 /* For second phase of HS mode */
285 hsscll = fclk_rate / (dev->speed * 2) - 6;
286 hssclh = fclk_rate / (dev->speed * 2) - 6;
288 /* To handle F/S modes */
289 fsscll = internal_clk / (dev->speed * 2) - 6;
290 fssclh = internal_clk / (dev->speed * 2) - 6;
292 scll = (hsscll << OMAP_I2C_SCLL_HSSCLL) | fsscll;
293 sclh = (hssclh << OMAP_I2C_SCLH_HSSCLH) | fssclh;
295 /* Program desired operating rate */
296 fclk_rate /= (psc + 1) * 1000;
299 scll = fclk_rate / (dev->speed * 2) - 7 + psc;
300 sclh = fclk_rate / (dev->speed * 2) - 7 + psc;
303 /* Setup clock prescaler to obtain approx 12MHz I2C module clock: */
304 omap_i2c_write_reg(dev, OMAP_I2C_PSC_REG, psc);
306 /* SCL low and high time values */
307 omap_i2c_write_reg(dev, OMAP_I2C_SCLL_REG, scll);
308 omap_i2c_write_reg(dev, OMAP_I2C_SCLH_REG, sclh);
311 /* Note: setup required fifo size - 1 */
312 omap_i2c_write_reg(dev, OMAP_I2C_BUF_REG,
313 (dev->fifo_size - 1) << 8 | /* RTRSH */
314 OMAP_I2C_BUF_RXFIF_CLR |
315 (dev->fifo_size - 1) | /* XTRSH */
316 OMAP_I2C_BUF_TXFIF_CLR);
318 /* Take the I2C module out of reset: */
319 omap_i2c_write_reg(dev, OMAP_I2C_CON_REG, OMAP_I2C_CON_EN);
321 /* Enable interrupts */
322 omap_i2c_write_reg(dev, OMAP_I2C_IE_REG,
323 (OMAP_I2C_IE_XRDY | OMAP_I2C_IE_RRDY |
324 OMAP_I2C_IE_ARDY | OMAP_I2C_IE_NACK |
325 OMAP_I2C_IE_AL) | ((dev->fifo_size) ?
326 (OMAP_I2C_IE_RDR | OMAP_I2C_IE_XDR) : 0));
331 * Waiting on Bus Busy
333 static int omap_i2c_wait_for_bb(struct omap_i2c_dev *dev)
335 unsigned long timeout;
337 timeout = jiffies + OMAP_I2C_TIMEOUT;
338 while (omap_i2c_read_reg(dev, OMAP_I2C_STAT_REG) & OMAP_I2C_STAT_BB) {
339 if (time_after(jiffies, timeout)) {
340 dev_warn(dev->dev, "timeout waiting for bus ready\n");
350 * Low level master read/write transaction.
352 static int omap_i2c_xfer_msg(struct i2c_adapter *adap,
353 struct i2c_msg *msg, int stop)
355 struct omap_i2c_dev *dev = i2c_get_adapdata(adap);
362 dev_dbg(dev->dev, "addr: 0x%04x, len: %d, flags: 0x%x, stop: %d\n",
363 msg->addr, msg->len, msg->flags, stop);
369 omap_i2c_write_reg(dev, OMAP_I2C_SA_REG, msg->addr);
371 /* REVISIT: Could the STB bit of I2C_CON be used with probing? */
373 dev->buf_len = msg->len;
377 omap_i2c_write_reg(dev, OMAP_I2C_SA_REG, msg->addr);
378 /* REVISIT: Remove this hack when we can get I2C chips from board-*.c
380 * Sigh, seems we can't do zero length transactions. Thus, we
381 * can't probe for devices w/o actually sending/receiving at least
382 * a single byte. So we'll set count to 1 for the zero length
383 * transaction case and hope we don't cause grief for some
384 * arbitrary device due to random byte write/read during
388 dev->buf = &zero_byte;
392 dev->buf_len = msg->len;
396 omap_i2c_write_reg(dev, OMAP_I2C_CNT_REG, dev->buf_len);
398 /* Clear the FIFO Buffers */
399 w = omap_i2c_read_reg(dev, OMAP_I2C_BUF_REG);
400 w |= OMAP_I2C_BUF_RXFIF_CLR | OMAP_I2C_BUF_TXFIF_CLR;
401 omap_i2c_write_reg(dev, OMAP_I2C_BUF_REG, w);
403 init_completion(&dev->cmd_complete);
406 w = OMAP_I2C_CON_EN | OMAP_I2C_CON_MST | OMAP_I2C_CON_STT;
408 /* High speed configuration */
409 if (dev->speed > 400)
410 w |= OMAP_I2C_CON_OPMODE_HS;
412 if (msg->flags & I2C_M_TEN)
413 w |= OMAP_I2C_CON_XA;
414 if (!(msg->flags & I2C_M_RD))
415 w |= OMAP_I2C_CON_TRX;
417 if (!dev->b_hw && stop)
418 w |= OMAP_I2C_CON_STP;
420 omap_i2c_write_reg(dev, OMAP_I2C_CON_REG, w);
422 if (dev->b_hw && stop) {
423 /* H/w behavior: dont write stt and stp together.. */
424 while (omap_i2c_read_reg(dev, OMAP_I2C_CON_REG) & OMAP_I2C_CON_STT) {
425 /* Dont do anything - this will come in a couple of loops at max*/
427 w |= OMAP_I2C_CON_STP;
428 w &= ~OMAP_I2C_CON_STT;
429 omap_i2c_write_reg(dev, OMAP_I2C_CON_REG, w);
431 r = wait_for_completion_timeout(&dev->cmd_complete,
437 dev_err(dev->dev, "controller timed out\n");
442 if (likely(!dev->cmd_err))
445 /* We have an error */
446 if (dev->cmd_err & (OMAP_I2C_STAT_AL | OMAP_I2C_STAT_ROVR |
447 OMAP_I2C_STAT_XUDF)) {
452 if (dev->cmd_err & OMAP_I2C_STAT_NACK) {
453 if (msg->flags & I2C_M_IGNORE_NAK)
456 w = omap_i2c_read_reg(dev, OMAP_I2C_CON_REG);
457 w |= OMAP_I2C_CON_STP;
458 omap_i2c_write_reg(dev, OMAP_I2C_CON_REG, w);
467 * Prepare controller for a transaction and call omap_i2c_xfer_msg
468 * to do the work during IRQ processing.
471 omap_i2c_xfer(struct i2c_adapter *adap, struct i2c_msg msgs[], int num)
473 struct omap_i2c_dev *dev = i2c_get_adapdata(adap);
477 omap_i2c_enable_clocks(dev);
479 /* REVISIT: initialize and use adap->retries. This is an optional
481 if ((r = omap_i2c_wait_for_bb(dev)) < 0)
484 for (i = 0; i < num; i++) {
485 r = omap_i2c_xfer_msg(adap, &msgs[i], (i == (num - 1)));
493 omap_i2c_disable_clocks(dev);
498 omap_i2c_func(struct i2c_adapter *adap)
501 return I2C_FUNC_I2C | (I2C_FUNC_SMBUS_EMUL & ~I2C_FUNC_SMBUS_QUICK);
503 return I2C_FUNC_I2C | I2C_FUNC_SMBUS_EMUL;
508 omap_i2c_complete_cmd(struct omap_i2c_dev *dev, u16 err)
511 complete(&dev->cmd_complete);
515 omap_i2c_ack_stat(struct omap_i2c_dev *dev, u16 stat)
517 omap_i2c_write_reg(dev, OMAP_I2C_STAT_REG, stat);
521 omap_i2c_rev1_isr(int this_irq, void *dev_id)
523 struct omap_i2c_dev *dev = dev_id;
526 iv = omap_i2c_read_reg(dev, OMAP_I2C_IV_REG);
528 case 0x00: /* None */
530 case 0x01: /* Arbitration lost */
531 dev_err(dev->dev, "Arbitration lost\n");
532 omap_i2c_complete_cmd(dev, OMAP_I2C_STAT_AL);
534 case 0x02: /* No acknowledgement */
535 omap_i2c_complete_cmd(dev, OMAP_I2C_STAT_NACK);
536 omap_i2c_write_reg(dev, OMAP_I2C_CON_REG, OMAP_I2C_CON_STP);
538 case 0x03: /* Register access ready */
539 omap_i2c_complete_cmd(dev, 0);
541 case 0x04: /* Receive data ready */
543 w = omap_i2c_read_reg(dev, OMAP_I2C_DATA_REG);
547 *dev->buf++ = w >> 8;
551 dev_err(dev->dev, "RRDY IRQ while no data requested\n");
553 case 0x05: /* Transmit data ready */
558 w |= *dev->buf++ << 8;
561 omap_i2c_write_reg(dev, OMAP_I2C_DATA_REG, w);
563 dev_err(dev->dev, "XRDY IRQ while no data to send\n");
573 omap_i2c_isr(int this_irq, void *dev_id)
575 struct omap_i2c_dev *dev = dev_id;
580 bits = omap_i2c_read_reg(dev, OMAP_I2C_IE_REG);
581 while ((stat = (omap_i2c_read_reg(dev, OMAP_I2C_STAT_REG))) & bits) {
582 dev_dbg(dev->dev, "IRQ (ISR = 0x%04x)\n", stat);
583 if (count++ == 100) {
584 dev_warn(dev->dev, "Too much work in one IRQ\n");
588 omap_i2c_write_reg(dev, OMAP_I2C_STAT_REG, stat);
590 if (stat & OMAP_I2C_STAT_ARDY) {
591 omap_i2c_complete_cmd(dev, 0);
594 if (stat & (OMAP_I2C_STAT_RRDY | OMAP_I2C_STAT_RDR)) {
596 if (dev->fifo_size) {
597 num_bytes = (stat & OMAP_I2C_STAT_RRDY) ? dev->fifo_size :
598 omap_i2c_read_reg(dev, OMAP_I2C_BUFSTAT_REG);
602 w = omap_i2c_read_reg(dev, OMAP_I2C_DATA_REG);
606 /* Data reg from 2430 is 8 bit wide */
607 if (!cpu_is_omap2430() &&
608 !cpu_is_omap34xx()) {
610 *dev->buf++ = w >> 8;
615 if (stat & OMAP_I2C_STAT_RRDY)
616 dev_err(dev->dev, "RRDY IRQ while no data "
618 if (stat & OMAP_I2C_STAT_RDR)
619 dev_err(dev->dev, "RDR IRQ while no data "
624 omap_i2c_ack_stat(dev, stat & (OMAP_I2C_STAT_RRDY | OMAP_I2C_STAT_RDR));
627 if (stat & (OMAP_I2C_STAT_XRDY | OMAP_I2C_STAT_XDR)) {
629 if (dev->fifo_size) {
630 num_bytes = (stat & OMAP_I2C_STAT_XRDY) ? dev->fifo_size :
631 omap_i2c_read_reg(dev, OMAP_I2C_BUFSTAT_REG);
639 /* Data reg from 2430 is 8 bit wide */
640 if (!cpu_is_omap2430() &&
641 !cpu_is_omap34xx()) {
643 w |= *dev->buf++ << 8;
648 if (stat & OMAP_I2C_STAT_XRDY)
649 dev_err(dev->dev, "XRDY IRQ while no "
651 if (stat & OMAP_I2C_STAT_XDR)
652 dev_err(dev->dev, "XDR IRQ while no "
656 omap_i2c_write_reg(dev, OMAP_I2C_DATA_REG, w);
658 omap_i2c_ack_stat(dev, stat & (OMAP_I2C_STAT_XRDY | OMAP_I2C_STAT_XDR));
661 if (stat & OMAP_I2C_STAT_ROVR) {
662 dev_err(dev->dev, "Receive overrun\n");
663 dev->cmd_err |= OMAP_I2C_STAT_ROVR;
665 if (stat & OMAP_I2C_STAT_XUDF) {
666 dev_err(dev->dev, "Transmit overflow\n");
667 dev->cmd_err |= OMAP_I2C_STAT_XUDF;
669 if (stat & OMAP_I2C_STAT_NACK) {
670 omap_i2c_complete_cmd(dev, OMAP_I2C_STAT_NACK);
671 omap_i2c_write_reg(dev, OMAP_I2C_CON_REG,
674 if (stat & OMAP_I2C_STAT_AL) {
675 dev_err(dev->dev, "Arbitration lost\n");
676 omap_i2c_complete_cmd(dev, OMAP_I2C_STAT_AL);
680 return count ? IRQ_HANDLED : IRQ_NONE;
683 static const struct i2c_algorithm omap_i2c_algo = {
684 .master_xfer = omap_i2c_xfer,
685 .functionality = omap_i2c_func,
689 omap_i2c_probe(struct platform_device *pdev)
691 struct omap_i2c_dev *dev;
692 struct i2c_adapter *adap;
693 struct resource *mem, *irq, *ioarea;
697 /* NOTE: driver uses the static register mapping */
698 mem = platform_get_resource(pdev, IORESOURCE_MEM, 0);
700 dev_err(&pdev->dev, "no mem resource?\n");
703 irq = platform_get_resource(pdev, IORESOURCE_IRQ, 0);
705 dev_err(&pdev->dev, "no irq resource?\n");
709 ioarea = request_mem_region(mem->start, (mem->end - mem->start) + 1,
712 dev_err(&pdev->dev, "I2C region already claimed\n");
716 dev = kzalloc(sizeof(struct omap_i2c_dev), GFP_KERNEL);
719 goto err_release_region;
722 if (pdev->dev.platform_data != NULL)
723 speed = (u32 *) pdev->dev.platform_data;
725 *speed = 100; /* Defualt speed */
728 dev->dev = &pdev->dev;
729 dev->irq = irq->start;
730 dev->base = (void __iomem *) IO_ADDRESS(mem->start);
731 platform_set_drvdata(pdev, dev);
733 if ((r = omap_i2c_get_clocks(dev)) != 0)
736 omap_i2c_enable_clocks(dev);
738 if (cpu_is_omap15xx())
739 dev->rev1 = omap_i2c_read_reg(dev, OMAP_I2C_REV_REG) < 0x20;
741 if (cpu_is_omap2430() || cpu_is_omap34xx()) {
742 /* Set up the fifo size - Get total size */
743 dev->fifo_size = 0x8 <<
744 ((omap_i2c_read_reg(dev, OMAP_I2C_BUFSTAT_REG) >> 14) & 0x3);
746 * Set up notification threshold as half the total available size
747 * This is to ensure that we can handle the status on int call back
750 dev->fifo_size = (dev->fifo_size / 2);
751 dev->b_hw = 1; /* Enable hardware fixes */
754 /* reset ASAP, clearing any IRQs */
757 r = request_irq(dev->irq, dev->rev1 ? omap_i2c_rev1_isr : omap_i2c_isr,
761 dev_err(dev->dev, "failure requesting irq %i\n", dev->irq);
762 goto err_unuse_clocks;
764 r = omap_i2c_read_reg(dev, OMAP_I2C_REV_REG) & 0xff;
765 dev_info(dev->dev, "bus %d rev%d.%d at %d kHz\n",
766 pdev->id, r >> 4, r & 0xf, dev->speed);
768 adap = &dev->adapter;
769 i2c_set_adapdata(adap, dev);
770 adap->owner = THIS_MODULE;
771 adap->class = I2C_CLASS_HWMON;
772 strncpy(adap->name, "OMAP I2C adapter", sizeof(adap->name));
773 adap->algo = &omap_i2c_algo;
774 adap->dev.parent = &pdev->dev;
776 /* i2c device drivers may be active on return from add_adapter() */
778 r = i2c_add_numbered_adapter(adap);
780 dev_err(dev->dev, "failure adding adapter\n");
784 omap_i2c_disable_clocks(dev);
789 free_irq(dev->irq, dev);
791 omap_i2c_disable_clocks(dev);
792 omap_i2c_put_clocks(dev);
794 platform_set_drvdata(pdev, NULL);
797 omap_i2c_write_reg(dev, OMAP_I2C_CON_REG, 0);
798 release_mem_region(mem->start, (mem->end - mem->start) + 1);
804 omap_i2c_remove(struct platform_device *pdev)
806 struct omap_i2c_dev *dev = platform_get_drvdata(pdev);
807 struct resource *mem;
809 platform_set_drvdata(pdev, NULL);
811 free_irq(dev->irq, dev);
812 i2c_del_adapter(&dev->adapter);
813 omap_i2c_write_reg(dev, OMAP_I2C_CON_REG, 0);
814 omap_i2c_put_clocks(dev);
816 mem = platform_get_resource(pdev, IORESOURCE_MEM, 0);
817 release_mem_region(mem->start, (mem->end - mem->start) + 1);
821 static struct platform_driver omap_i2c_driver = {
822 .probe = omap_i2c_probe,
823 .remove = omap_i2c_remove,
826 .owner = THIS_MODULE,
830 /* I2C may be needed to bring up other drivers */
832 omap_i2c_init_driver(void)
834 return platform_driver_register(&omap_i2c_driver);
836 subsys_initcall(omap_i2c_init_driver);
838 static void __exit omap_i2c_exit_driver(void)
840 platform_driver_unregister(&omap_i2c_driver);
842 module_exit(omap_i2c_exit_driver);
844 MODULE_AUTHOR("MontaVista Software, Inc. (and others)");
845 MODULE_DESCRIPTION("TI OMAP I2C bus adapter");
846 MODULE_LICENSE("GPL");