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Merge branch 'i2c/for-next' of git://git.kernel.org/pub/scm/linux/kernel/git/wsa...
[deliverable/linux.git] / drivers / i2c / busses / i2c-imx.c
1 /*
2 * Copyright (C) 2002 Motorola GSG-China
3 *
4 * This program is free software; you can redistribute it and/or
5 * modify it under the terms of the GNU General Public License
6 * as published by the Free Software Foundation; either version 2
7 * of the License, or (at your option) any later version.
8 *
9 * This program is distributed in the hope that it will be useful,
10 * but WITHOUT ANY WARRANTY; without even the implied warranty of
11 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
12 * GNU General Public License for more details.
13 *
14 * You should have received a copy of the GNU General Public License
15 * along with this program; if not, write to the Free Software
16 * Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307,
17 * USA.
18 *
19 * Author:
20 * Darius Augulis, Teltonika Inc.
21 *
22 * Desc.:
23 * Implementation of I2C Adapter/Algorithm Driver
24 * for I2C Bus integrated in Freescale i.MX/MXC processors
25 *
26 * Derived from Motorola GSG China I2C example driver
27 *
28 * Copyright (C) 2005 Torsten Koschorrek <koschorrek at synertronixx.de
29 * Copyright (C) 2005 Matthias Blaschke <blaschke at synertronixx.de
30 * Copyright (C) 2007 RightHand Technologies, Inc.
31 * Copyright (C) 2008 Darius Augulis <darius.augulis at teltonika.lt>
32 *
33 */
34
35 /** Includes *******************************************************************
36 *******************************************************************************/
37
38 #include <linux/init.h>
39 #include <linux/kernel.h>
40 #include <linux/module.h>
41 #include <linux/errno.h>
42 #include <linux/err.h>
43 #include <linux/interrupt.h>
44 #include <linux/delay.h>
45 #include <linux/i2c.h>
46 #include <linux/io.h>
47 #include <linux/sched.h>
48 #include <linux/platform_device.h>
49 #include <linux/clk.h>
50 #include <linux/slab.h>
51 #include <linux/of.h>
52 #include <linux/of_device.h>
53 #include <linux/of_i2c.h>
54 #include <linux/pinctrl/consumer.h>
55 #include <linux/platform_data/i2c-imx.h>
56
57 /** Defines ********************************************************************
58 *******************************************************************************/
59
60 /* This will be the driver name the kernel reports */
61 #define DRIVER_NAME "imx-i2c"
62
63 /* Default value */
64 #define IMX_I2C_BIT_RATE 100000 /* 100kHz */
65
66 /* IMX I2C registers */
67 #define IMX_I2C_IADR 0x00 /* i2c slave address */
68 #define IMX_I2C_IFDR 0x04 /* i2c frequency divider */
69 #define IMX_I2C_I2CR 0x08 /* i2c control */
70 #define IMX_I2C_I2SR 0x0C /* i2c status */
71 #define IMX_I2C_I2DR 0x10 /* i2c transfer data */
72
73 /* Bits of IMX I2C registers */
74 #define I2SR_RXAK 0x01
75 #define I2SR_IIF 0x02
76 #define I2SR_SRW 0x04
77 #define I2SR_IAL 0x10
78 #define I2SR_IBB 0x20
79 #define I2SR_IAAS 0x40
80 #define I2SR_ICF 0x80
81 #define I2CR_RSTA 0x04
82 #define I2CR_TXAK 0x08
83 #define I2CR_MTX 0x10
84 #define I2CR_MSTA 0x20
85 #define I2CR_IIEN 0x40
86 #define I2CR_IEN 0x80
87
88 /** Variables ******************************************************************
89 *******************************************************************************/
90
91 /*
92 * sorted list of clock divider, register value pairs
93 * taken from table 26-5, p.26-9, Freescale i.MX
94 * Integrated Portable System Processor Reference Manual
95 * Document Number: MC9328MXLRM, Rev. 5.1, 06/2007
96 *
97 * Duplicated divider values removed from list
98 */
99
100 static u16 __initdata i2c_clk_div[50][2] = {
101 { 22, 0x20 }, { 24, 0x21 }, { 26, 0x22 }, { 28, 0x23 },
102 { 30, 0x00 }, { 32, 0x24 }, { 36, 0x25 }, { 40, 0x26 },
103 { 42, 0x03 }, { 44, 0x27 }, { 48, 0x28 }, { 52, 0x05 },
104 { 56, 0x29 }, { 60, 0x06 }, { 64, 0x2A }, { 72, 0x2B },
105 { 80, 0x2C }, { 88, 0x09 }, { 96, 0x2D }, { 104, 0x0A },
106 { 112, 0x2E }, { 128, 0x2F }, { 144, 0x0C }, { 160, 0x30 },
107 { 192, 0x31 }, { 224, 0x32 }, { 240, 0x0F }, { 256, 0x33 },
108 { 288, 0x10 }, { 320, 0x34 }, { 384, 0x35 }, { 448, 0x36 },
109 { 480, 0x13 }, { 512, 0x37 }, { 576, 0x14 }, { 640, 0x38 },
110 { 768, 0x39 }, { 896, 0x3A }, { 960, 0x17 }, { 1024, 0x3B },
111 { 1152, 0x18 }, { 1280, 0x3C }, { 1536, 0x3D }, { 1792, 0x3E },
112 { 1920, 0x1B }, { 2048, 0x3F }, { 2304, 0x1C }, { 2560, 0x1D },
113 { 3072, 0x1E }, { 3840, 0x1F }
114 };
115
116 enum imx_i2c_type {
117 IMX1_I2C,
118 IMX21_I2C,
119 };
120
121 struct imx_i2c_struct {
122 struct i2c_adapter adapter;
123 struct clk *clk;
124 void __iomem *base;
125 wait_queue_head_t queue;
126 unsigned long i2csr;
127 unsigned int disable_delay;
128 int stopped;
129 unsigned int ifdr; /* IMX_I2C_IFDR */
130 enum imx_i2c_type devtype;
131 };
132
133 static struct platform_device_id imx_i2c_devtype[] = {
134 {
135 .name = "imx1-i2c",
136 .driver_data = IMX1_I2C,
137 }, {
138 .name = "imx21-i2c",
139 .driver_data = IMX21_I2C,
140 }, {
141 /* sentinel */
142 }
143 };
144 MODULE_DEVICE_TABLE(platform, imx_i2c_devtype);
145
146 static const struct of_device_id i2c_imx_dt_ids[] = {
147 { .compatible = "fsl,imx1-i2c", .data = &imx_i2c_devtype[IMX1_I2C], },
148 { .compatible = "fsl,imx21-i2c", .data = &imx_i2c_devtype[IMX21_I2C], },
149 { /* sentinel */ }
150 };
151
152 static inline int is_imx1_i2c(struct imx_i2c_struct *i2c_imx)
153 {
154 return i2c_imx->devtype == IMX1_I2C;
155 }
156
157 /** Functions for IMX I2C adapter driver ***************************************
158 *******************************************************************************/
159
160 static int i2c_imx_bus_busy(struct imx_i2c_struct *i2c_imx, int for_busy)
161 {
162 unsigned long orig_jiffies = jiffies;
163 unsigned int temp;
164
165 dev_dbg(&i2c_imx->adapter.dev, "<%s>\n", __func__);
166
167 while (1) {
168 temp = readb(i2c_imx->base + IMX_I2C_I2SR);
169 if (for_busy && (temp & I2SR_IBB))
170 break;
171 if (!for_busy && !(temp & I2SR_IBB))
172 break;
173 if (time_after(jiffies, orig_jiffies + msecs_to_jiffies(500))) {
174 dev_dbg(&i2c_imx->adapter.dev,
175 "<%s> I2C bus is busy\n", __func__);
176 return -ETIMEDOUT;
177 }
178 schedule();
179 }
180
181 return 0;
182 }
183
184 static int i2c_imx_trx_complete(struct imx_i2c_struct *i2c_imx)
185 {
186 wait_event_timeout(i2c_imx->queue, i2c_imx->i2csr & I2SR_IIF, HZ / 10);
187
188 if (unlikely(!(i2c_imx->i2csr & I2SR_IIF))) {
189 dev_dbg(&i2c_imx->adapter.dev, "<%s> Timeout\n", __func__);
190 return -ETIMEDOUT;
191 }
192 dev_dbg(&i2c_imx->adapter.dev, "<%s> TRX complete\n", __func__);
193 i2c_imx->i2csr = 0;
194 return 0;
195 }
196
197 static int i2c_imx_acked(struct imx_i2c_struct *i2c_imx)
198 {
199 if (readb(i2c_imx->base + IMX_I2C_I2SR) & I2SR_RXAK) {
200 dev_dbg(&i2c_imx->adapter.dev, "<%s> No ACK\n", __func__);
201 return -EIO; /* No ACK */
202 }
203
204 dev_dbg(&i2c_imx->adapter.dev, "<%s> ACK received\n", __func__);
205 return 0;
206 }
207
208 static int i2c_imx_start(struct imx_i2c_struct *i2c_imx)
209 {
210 unsigned int temp = 0;
211 int result;
212
213 dev_dbg(&i2c_imx->adapter.dev, "<%s>\n", __func__);
214
215 clk_prepare_enable(i2c_imx->clk);
216 writeb(i2c_imx->ifdr, i2c_imx->base + IMX_I2C_IFDR);
217 /* Enable I2C controller */
218 writeb(0, i2c_imx->base + IMX_I2C_I2SR);
219 writeb(I2CR_IEN, i2c_imx->base + IMX_I2C_I2CR);
220
221 /* Wait controller to be stable */
222 udelay(50);
223
224 /* Start I2C transaction */
225 temp = readb(i2c_imx->base + IMX_I2C_I2CR);
226 temp |= I2CR_MSTA;
227 writeb(temp, i2c_imx->base + IMX_I2C_I2CR);
228 result = i2c_imx_bus_busy(i2c_imx, 1);
229 if (result)
230 return result;
231 i2c_imx->stopped = 0;
232
233 temp |= I2CR_IIEN | I2CR_MTX | I2CR_TXAK;
234 writeb(temp, i2c_imx->base + IMX_I2C_I2CR);
235 return result;
236 }
237
238 static void i2c_imx_stop(struct imx_i2c_struct *i2c_imx)
239 {
240 unsigned int temp = 0;
241
242 if (!i2c_imx->stopped) {
243 /* Stop I2C transaction */
244 dev_dbg(&i2c_imx->adapter.dev, "<%s>\n", __func__);
245 temp = readb(i2c_imx->base + IMX_I2C_I2CR);
246 temp &= ~(I2CR_MSTA | I2CR_MTX);
247 writeb(temp, i2c_imx->base + IMX_I2C_I2CR);
248 }
249 if (is_imx1_i2c(i2c_imx)) {
250 /*
251 * This delay caused by an i.MXL hardware bug.
252 * If no (or too short) delay, no "STOP" bit will be generated.
253 */
254 udelay(i2c_imx->disable_delay);
255 }
256
257 if (!i2c_imx->stopped) {
258 i2c_imx_bus_busy(i2c_imx, 0);
259 i2c_imx->stopped = 1;
260 }
261
262 /* Disable I2C controller */
263 writeb(0, i2c_imx->base + IMX_I2C_I2CR);
264 clk_disable_unprepare(i2c_imx->clk);
265 }
266
267 static void __init i2c_imx_set_clk(struct imx_i2c_struct *i2c_imx,
268 unsigned int rate)
269 {
270 unsigned int i2c_clk_rate;
271 unsigned int div;
272 int i;
273
274 /* Divider value calculation */
275 i2c_clk_rate = clk_get_rate(i2c_imx->clk);
276 div = (i2c_clk_rate + rate - 1) / rate;
277 if (div < i2c_clk_div[0][0])
278 i = 0;
279 else if (div > i2c_clk_div[ARRAY_SIZE(i2c_clk_div) - 1][0])
280 i = ARRAY_SIZE(i2c_clk_div) - 1;
281 else
282 for (i = 0; i2c_clk_div[i][0] < div; i++);
283
284 /* Store divider value */
285 i2c_imx->ifdr = i2c_clk_div[i][1];
286
287 /*
288 * There dummy delay is calculated.
289 * It should be about one I2C clock period long.
290 * This delay is used in I2C bus disable function
291 * to fix chip hardware bug.
292 */
293 i2c_imx->disable_delay = (500000U * i2c_clk_div[i][0]
294 + (i2c_clk_rate / 2) - 1) / (i2c_clk_rate / 2);
295
296 /* dev_dbg() can't be used, because adapter is not yet registered */
297 #ifdef CONFIG_I2C_DEBUG_BUS
298 dev_dbg(&i2c_imx->adapter.dev, "<%s> I2C_CLK=%d, REQ DIV=%d\n",
299 __func__, i2c_clk_rate, div);
300 dev_dbg(&i2c_imx->adapter.dev, "<%s> IFDR[IC]=0x%x, REAL DIV=%d\n",
301 __func__, i2c_clk_div[i][1], i2c_clk_div[i][0]);
302 #endif
303 }
304
305 static irqreturn_t i2c_imx_isr(int irq, void *dev_id)
306 {
307 struct imx_i2c_struct *i2c_imx = dev_id;
308 unsigned int temp;
309
310 temp = readb(i2c_imx->base + IMX_I2C_I2SR);
311 if (temp & I2SR_IIF) {
312 /* save status register */
313 i2c_imx->i2csr = temp;
314 temp &= ~I2SR_IIF;
315 writeb(temp, i2c_imx->base + IMX_I2C_I2SR);
316 wake_up(&i2c_imx->queue);
317 return IRQ_HANDLED;
318 }
319
320 return IRQ_NONE;
321 }
322
323 static int i2c_imx_write(struct imx_i2c_struct *i2c_imx, struct i2c_msg *msgs)
324 {
325 int i, result;
326
327 dev_dbg(&i2c_imx->adapter.dev, "<%s> write slave address: addr=0x%x\n",
328 __func__, msgs->addr << 1);
329
330 /* write slave address */
331 writeb(msgs->addr << 1, i2c_imx->base + IMX_I2C_I2DR);
332 result = i2c_imx_trx_complete(i2c_imx);
333 if (result)
334 return result;
335 result = i2c_imx_acked(i2c_imx);
336 if (result)
337 return result;
338 dev_dbg(&i2c_imx->adapter.dev, "<%s> write data\n", __func__);
339
340 /* write data */
341 for (i = 0; i < msgs->len; i++) {
342 dev_dbg(&i2c_imx->adapter.dev,
343 "<%s> write byte: B%d=0x%X\n",
344 __func__, i, msgs->buf[i]);
345 writeb(msgs->buf[i], i2c_imx->base + IMX_I2C_I2DR);
346 result = i2c_imx_trx_complete(i2c_imx);
347 if (result)
348 return result;
349 result = i2c_imx_acked(i2c_imx);
350 if (result)
351 return result;
352 }
353 return 0;
354 }
355
356 static int i2c_imx_read(struct imx_i2c_struct *i2c_imx, struct i2c_msg *msgs)
357 {
358 int i, result;
359 unsigned int temp;
360
361 dev_dbg(&i2c_imx->adapter.dev,
362 "<%s> write slave address: addr=0x%x\n",
363 __func__, (msgs->addr << 1) | 0x01);
364
365 /* write slave address */
366 writeb((msgs->addr << 1) | 0x01, i2c_imx->base + IMX_I2C_I2DR);
367 result = i2c_imx_trx_complete(i2c_imx);
368 if (result)
369 return result;
370 result = i2c_imx_acked(i2c_imx);
371 if (result)
372 return result;
373
374 dev_dbg(&i2c_imx->adapter.dev, "<%s> setup bus\n", __func__);
375
376 /* setup bus to read data */
377 temp = readb(i2c_imx->base + IMX_I2C_I2CR);
378 temp &= ~I2CR_MTX;
379 if (msgs->len - 1)
380 temp &= ~I2CR_TXAK;
381 writeb(temp, i2c_imx->base + IMX_I2C_I2CR);
382 readb(i2c_imx->base + IMX_I2C_I2DR); /* dummy read */
383
384 dev_dbg(&i2c_imx->adapter.dev, "<%s> read data\n", __func__);
385
386 /* read data */
387 for (i = 0; i < msgs->len; i++) {
388 result = i2c_imx_trx_complete(i2c_imx);
389 if (result)
390 return result;
391 if (i == (msgs->len - 1)) {
392 /* It must generate STOP before read I2DR to prevent
393 controller from generating another clock cycle */
394 dev_dbg(&i2c_imx->adapter.dev,
395 "<%s> clear MSTA\n", __func__);
396 temp = readb(i2c_imx->base + IMX_I2C_I2CR);
397 temp &= ~(I2CR_MSTA | I2CR_MTX);
398 writeb(temp, i2c_imx->base + IMX_I2C_I2CR);
399 i2c_imx_bus_busy(i2c_imx, 0);
400 i2c_imx->stopped = 1;
401 } else if (i == (msgs->len - 2)) {
402 dev_dbg(&i2c_imx->adapter.dev,
403 "<%s> set TXAK\n", __func__);
404 temp = readb(i2c_imx->base + IMX_I2C_I2CR);
405 temp |= I2CR_TXAK;
406 writeb(temp, i2c_imx->base + IMX_I2C_I2CR);
407 }
408 msgs->buf[i] = readb(i2c_imx->base + IMX_I2C_I2DR);
409 dev_dbg(&i2c_imx->adapter.dev,
410 "<%s> read byte: B%d=0x%X\n",
411 __func__, i, msgs->buf[i]);
412 }
413 return 0;
414 }
415
416 static int i2c_imx_xfer(struct i2c_adapter *adapter,
417 struct i2c_msg *msgs, int num)
418 {
419 unsigned int i, temp;
420 int result;
421 struct imx_i2c_struct *i2c_imx = i2c_get_adapdata(adapter);
422
423 dev_dbg(&i2c_imx->adapter.dev, "<%s>\n", __func__);
424
425 /* Start I2C transfer */
426 result = i2c_imx_start(i2c_imx);
427 if (result)
428 goto fail0;
429
430 /* read/write data */
431 for (i = 0; i < num; i++) {
432 if (i) {
433 dev_dbg(&i2c_imx->adapter.dev,
434 "<%s> repeated start\n", __func__);
435 temp = readb(i2c_imx->base + IMX_I2C_I2CR);
436 temp |= I2CR_RSTA;
437 writeb(temp, i2c_imx->base + IMX_I2C_I2CR);
438 result = i2c_imx_bus_busy(i2c_imx, 1);
439 if (result)
440 goto fail0;
441 }
442 dev_dbg(&i2c_imx->adapter.dev,
443 "<%s> transfer message: %d\n", __func__, i);
444 /* write/read data */
445 #ifdef CONFIG_I2C_DEBUG_BUS
446 temp = readb(i2c_imx->base + IMX_I2C_I2CR);
447 dev_dbg(&i2c_imx->adapter.dev, "<%s> CONTROL: IEN=%d, IIEN=%d, "
448 "MSTA=%d, MTX=%d, TXAK=%d, RSTA=%d\n", __func__,
449 (temp & I2CR_IEN ? 1 : 0), (temp & I2CR_IIEN ? 1 : 0),
450 (temp & I2CR_MSTA ? 1 : 0), (temp & I2CR_MTX ? 1 : 0),
451 (temp & I2CR_TXAK ? 1 : 0), (temp & I2CR_RSTA ? 1 : 0));
452 temp = readb(i2c_imx->base + IMX_I2C_I2SR);
453 dev_dbg(&i2c_imx->adapter.dev,
454 "<%s> STATUS: ICF=%d, IAAS=%d, IBB=%d, "
455 "IAL=%d, SRW=%d, IIF=%d, RXAK=%d\n", __func__,
456 (temp & I2SR_ICF ? 1 : 0), (temp & I2SR_IAAS ? 1 : 0),
457 (temp & I2SR_IBB ? 1 : 0), (temp & I2SR_IAL ? 1 : 0),
458 (temp & I2SR_SRW ? 1 : 0), (temp & I2SR_IIF ? 1 : 0),
459 (temp & I2SR_RXAK ? 1 : 0));
460 #endif
461 if (msgs[i].flags & I2C_M_RD)
462 result = i2c_imx_read(i2c_imx, &msgs[i]);
463 else
464 result = i2c_imx_write(i2c_imx, &msgs[i]);
465 if (result)
466 goto fail0;
467 }
468
469 fail0:
470 /* Stop I2C transfer */
471 i2c_imx_stop(i2c_imx);
472
473 dev_dbg(&i2c_imx->adapter.dev, "<%s> exit with: %s: %d\n", __func__,
474 (result < 0) ? "error" : "success msg",
475 (result < 0) ? result : num);
476 return (result < 0) ? result : num;
477 }
478
479 static u32 i2c_imx_func(struct i2c_adapter *adapter)
480 {
481 return I2C_FUNC_I2C | I2C_FUNC_SMBUS_EMUL;
482 }
483
484 static struct i2c_algorithm i2c_imx_algo = {
485 .master_xfer = i2c_imx_xfer,
486 .functionality = i2c_imx_func,
487 };
488
489 static int __init i2c_imx_probe(struct platform_device *pdev)
490 {
491 const struct of_device_id *of_id = of_match_device(i2c_imx_dt_ids,
492 &pdev->dev);
493 struct imx_i2c_struct *i2c_imx;
494 struct resource *res;
495 struct imxi2c_platform_data *pdata = pdev->dev.platform_data;
496 struct pinctrl *pinctrl;
497 void __iomem *base;
498 int irq, ret;
499 u32 bitrate;
500
501 dev_dbg(&pdev->dev, "<%s>\n", __func__);
502
503 res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
504 if (!res) {
505 dev_err(&pdev->dev, "can't get device resources\n");
506 return -ENOENT;
507 }
508 irq = platform_get_irq(pdev, 0);
509 if (irq < 0) {
510 dev_err(&pdev->dev, "can't get irq number\n");
511 return -ENOENT;
512 }
513
514 base = devm_ioremap_resource(&pdev->dev, res);
515 if (IS_ERR(base))
516 return PTR_ERR(base);
517
518 i2c_imx = devm_kzalloc(&pdev->dev, sizeof(struct imx_i2c_struct),
519 GFP_KERNEL);
520 if (!i2c_imx) {
521 dev_err(&pdev->dev, "can't allocate interface\n");
522 return -ENOMEM;
523 }
524
525 if (of_id)
526 pdev->id_entry = of_id->data;
527 i2c_imx->devtype = pdev->id_entry->driver_data;
528
529 /* Setup i2c_imx driver structure */
530 strlcpy(i2c_imx->adapter.name, pdev->name, sizeof(i2c_imx->adapter.name));
531 i2c_imx->adapter.owner = THIS_MODULE;
532 i2c_imx->adapter.algo = &i2c_imx_algo;
533 i2c_imx->adapter.dev.parent = &pdev->dev;
534 i2c_imx->adapter.nr = pdev->id;
535 i2c_imx->adapter.dev.of_node = pdev->dev.of_node;
536 i2c_imx->base = base;
537
538 pinctrl = devm_pinctrl_get_select_default(&pdev->dev);
539 if (IS_ERR(pinctrl)) {
540 dev_err(&pdev->dev, "can't get/select pinctrl\n");
541 return PTR_ERR(pinctrl);
542 }
543
544 /* Get I2C clock */
545 i2c_imx->clk = devm_clk_get(&pdev->dev, NULL);
546 if (IS_ERR(i2c_imx->clk)) {
547 dev_err(&pdev->dev, "can't get I2C clock\n");
548 return PTR_ERR(i2c_imx->clk);
549 }
550
551 /* Request IRQ */
552 ret = devm_request_irq(&pdev->dev, irq, i2c_imx_isr, 0,
553 pdev->name, i2c_imx);
554 if (ret) {
555 dev_err(&pdev->dev, "can't claim irq %d\n", irq);
556 return ret;
557 }
558
559 /* Init queue */
560 init_waitqueue_head(&i2c_imx->queue);
561
562 /* Set up adapter data */
563 i2c_set_adapdata(&i2c_imx->adapter, i2c_imx);
564
565 /* Set up clock divider */
566 bitrate = IMX_I2C_BIT_RATE;
567 ret = of_property_read_u32(pdev->dev.of_node,
568 "clock-frequency", &bitrate);
569 if (ret < 0 && pdata && pdata->bitrate)
570 bitrate = pdata->bitrate;
571 i2c_imx_set_clk(i2c_imx, bitrate);
572
573 /* Set up chip registers to defaults */
574 writeb(0, i2c_imx->base + IMX_I2C_I2CR);
575 writeb(0, i2c_imx->base + IMX_I2C_I2SR);
576
577 /* Add I2C adapter */
578 ret = i2c_add_numbered_adapter(&i2c_imx->adapter);
579 if (ret < 0) {
580 dev_err(&pdev->dev, "registration failed\n");
581 return ret;
582 }
583
584 of_i2c_register_devices(&i2c_imx->adapter);
585
586 /* Set up platform driver data */
587 platform_set_drvdata(pdev, i2c_imx);
588
589 dev_dbg(&i2c_imx->adapter.dev, "claimed irq %d\n", irq);
590 dev_dbg(&i2c_imx->adapter.dev, "device resources from 0x%x to 0x%x\n",
591 res->start, res->end);
592 dev_dbg(&i2c_imx->adapter.dev, "allocated %d bytes at 0x%x\n",
593 resource_size(res), res->start);
594 dev_dbg(&i2c_imx->adapter.dev, "adapter name: \"%s\"\n",
595 i2c_imx->adapter.name);
596 dev_info(&i2c_imx->adapter.dev, "IMX I2C adapter registered\n");
597
598 return 0; /* Return OK */
599 }
600
601 static int __exit i2c_imx_remove(struct platform_device *pdev)
602 {
603 struct imx_i2c_struct *i2c_imx = platform_get_drvdata(pdev);
604
605 /* remove adapter */
606 dev_dbg(&i2c_imx->adapter.dev, "adapter removed\n");
607 i2c_del_adapter(&i2c_imx->adapter);
608
609 /* setup chip registers to defaults */
610 writeb(0, i2c_imx->base + IMX_I2C_IADR);
611 writeb(0, i2c_imx->base + IMX_I2C_IFDR);
612 writeb(0, i2c_imx->base + IMX_I2C_I2CR);
613 writeb(0, i2c_imx->base + IMX_I2C_I2SR);
614
615 return 0;
616 }
617
618 static struct platform_driver i2c_imx_driver = {
619 .remove = __exit_p(i2c_imx_remove),
620 .driver = {
621 .name = DRIVER_NAME,
622 .owner = THIS_MODULE,
623 .of_match_table = i2c_imx_dt_ids,
624 },
625 .id_table = imx_i2c_devtype,
626 };
627
628 static int __init i2c_adap_imx_init(void)
629 {
630 return platform_driver_probe(&i2c_imx_driver, i2c_imx_probe);
631 }
632 subsys_initcall(i2c_adap_imx_init);
633
634 static void __exit i2c_adap_imx_exit(void)
635 {
636 platform_driver_unregister(&i2c_imx_driver);
637 }
638 module_exit(i2c_adap_imx_exit);
639
640 MODULE_LICENSE("GPL");
641 MODULE_AUTHOR("Darius Augulis");
642 MODULE_DESCRIPTION("I2C adapter driver for IMX I2C bus");
643 MODULE_ALIAS("platform:" DRIVER_NAME);
Linux kernel - Deliverables
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