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Avoid beyond bounds copy while caching ACL
[zen-stable.git] / drivers / i2c / busses / i2c-imx.c
blob58832e578fff24dbbff08b38eb82e093a2cf36df
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
55 #include <mach/irqs.h>
56 #include <mach/hardware.h>
57 #include <mach/i2c.h>
58
59 /** Defines ********************************************************************
60 *******************************************************************************/
61
62 /* This will be the driver name the kernel reports */
63 #define DRIVER_NAME "imx-i2c"
64
65 /* Default value */
66 #define IMX_I2C_BIT_RATE 100000 /* 100kHz */
67
68 /* IMX I2C registers */
69 #define IMX_I2C_IADR 0x00 /* i2c slave address */
70 #define IMX_I2C_IFDR 0x04 /* i2c frequency divider */
71 #define IMX_I2C_I2CR 0x08 /* i2c control */
72 #define IMX_I2C_I2SR 0x0C /* i2c status */
73 #define IMX_I2C_I2DR 0x10 /* i2c transfer data */
74
75 /* Bits of IMX I2C registers */
76 #define I2SR_RXAK 0x01
77 #define I2SR_IIF 0x02
78 #define I2SR_SRW 0x04
79 #define I2SR_IAL 0x10
80 #define I2SR_IBB 0x20
81 #define I2SR_IAAS 0x40
82 #define I2SR_ICF 0x80
83 #define I2CR_RSTA 0x04
84 #define I2CR_TXAK 0x08
85 #define I2CR_MTX 0x10
86 #define I2CR_MSTA 0x20
87 #define I2CR_IIEN 0x40
88 #define I2CR_IEN 0x80
89
90 /** Variables ******************************************************************
91 *******************************************************************************/
92
93 /*
94 * sorted list of clock divider, register value pairs
95 * taken from table 26-5, p.26-9, Freescale i.MX
96 * Integrated Portable System Processor Reference Manual
97 * Document Number: MC9328MXLRM, Rev. 5.1, 06/2007
98 *
99 * Duplicated divider values removed from list
100 */
101
102 static u16 __initdata i2c_clk_div[50][2] = {
103 { 22, 0x20 }, { 24, 0x21 }, { 26, 0x22 }, { 28, 0x23 },
104 { 30, 0x00 }, { 32, 0x24 }, { 36, 0x25 }, { 40, 0x26 },
105 { 42, 0x03 }, { 44, 0x27 }, { 48, 0x28 }, { 52, 0x05 },
106 { 56, 0x29 }, { 60, 0x06 }, { 64, 0x2A }, { 72, 0x2B },
107 { 80, 0x2C }, { 88, 0x09 }, { 96, 0x2D }, { 104, 0x0A },
108 { 112, 0x2E }, { 128, 0x2F }, { 144, 0x0C }, { 160, 0x30 },
109 { 192, 0x31 }, { 224, 0x32 }, { 240, 0x0F }, { 256, 0x33 },
110 { 288, 0x10 }, { 320, 0x34 }, { 384, 0x35 }, { 448, 0x36 },
111 { 480, 0x13 }, { 512, 0x37 }, { 576, 0x14 }, { 640, 0x38 },
112 { 768, 0x39 }, { 896, 0x3A }, { 960, 0x17 }, { 1024, 0x3B },
113 { 1152, 0x18 }, { 1280, 0x3C }, { 1536, 0x3D }, { 1792, 0x3E },
114 { 1920, 0x1B }, { 2048, 0x3F }, { 2304, 0x1C }, { 2560, 0x1D },
115 { 3072, 0x1E }, { 3840, 0x1F }
116 };
117
118 struct imx_i2c_struct {
119 struct i2c_adapter adapter;
120 struct resource *res;
121 struct clk *clk;
122 void __iomem *base;
123 int irq;
124 wait_queue_head_t queue;
125 unsigned long i2csr;
126 unsigned int disable_delay;
127 int stopped;
128 unsigned int ifdr; /* IMX_I2C_IFDR */
129 };
130
131 static const struct of_device_id i2c_imx_dt_ids[] = {
132 { .compatible = "fsl,imx1-i2c", },
133 { /* sentinel */ }
134 };
135
136 /** Functions for IMX I2C adapter driver ***************************************
137 *******************************************************************************/
138
139 static int i2c_imx_bus_busy(struct imx_i2c_struct *i2c_imx, int for_busy)
140 {
141 unsigned long orig_jiffies = jiffies;
142 unsigned int temp;
143
144 dev_dbg(&i2c_imx->adapter.dev, "<%s>\n", __func__);
145
146 while (1) {
147 temp = readb(i2c_imx->base + IMX_I2C_I2SR);
148 if (for_busy && (temp & I2SR_IBB))
149 break;
150 if (!for_busy && !(temp & I2SR_IBB))
151 break;
152 if (signal_pending(current)) {
153 dev_dbg(&i2c_imx->adapter.dev,
154 "<%s> I2C Interrupted\n", __func__);
155 return -EINTR;
156 }
157 if (time_after(jiffies, orig_jiffies + msecs_to_jiffies(500))) {
158 dev_dbg(&i2c_imx->adapter.dev,
159 "<%s> I2C bus is busy\n", __func__);
160 return -ETIMEDOUT;
161 }
162 schedule();
163 }
164
165 return 0;
166 }
167
168 static int i2c_imx_trx_complete(struct imx_i2c_struct *i2c_imx)
169 {
170 wait_event_timeout(i2c_imx->queue, i2c_imx->i2csr & I2SR_IIF, HZ / 10);
171
172 if (unlikely(!(i2c_imx->i2csr & I2SR_IIF))) {
173 dev_dbg(&i2c_imx->adapter.dev, "<%s> Timeout\n", __func__);
174 return -ETIMEDOUT;
175 }
176 dev_dbg(&i2c_imx->adapter.dev, "<%s> TRX complete\n", __func__);
177 i2c_imx->i2csr = 0;
178 return 0;
179 }
180
181 static int i2c_imx_acked(struct imx_i2c_struct *i2c_imx)
182 {
183 if (readb(i2c_imx->base + IMX_I2C_I2SR) & I2SR_RXAK) {
184 dev_dbg(&i2c_imx->adapter.dev, "<%s> No ACK\n", __func__);
185 return -EIO; /* No ACK */
186 }
187
188 dev_dbg(&i2c_imx->adapter.dev, "<%s> ACK received\n", __func__);
189 return 0;
190 }
191
192 static int i2c_imx_start(struct imx_i2c_struct *i2c_imx)
193 {
194 unsigned int temp = 0;
195 int result;
196
197 dev_dbg(&i2c_imx->adapter.dev, "<%s>\n", __func__);
198
199 clk_enable(i2c_imx->clk);
200 writeb(i2c_imx->ifdr, i2c_imx->base + IMX_I2C_IFDR);
201 /* Enable I2C controller */
202 writeb(0, i2c_imx->base + IMX_I2C_I2SR);
203 writeb(I2CR_IEN, i2c_imx->base + IMX_I2C_I2CR);
204
205 /* Wait controller to be stable */
206 udelay(50);
207
208 /* Start I2C transaction */
209 temp = readb(i2c_imx->base + IMX_I2C_I2CR);
210 temp |= I2CR_MSTA;
211 writeb(temp, i2c_imx->base + IMX_I2C_I2CR);
212 result = i2c_imx_bus_busy(i2c_imx, 1);
213 if (result)
214 return result;
215 i2c_imx->stopped = 0;
216
217 temp |= I2CR_IIEN | I2CR_MTX | I2CR_TXAK;
218 writeb(temp, i2c_imx->base + IMX_I2C_I2CR);
219 return result;
220 }
221
222 static void i2c_imx_stop(struct imx_i2c_struct *i2c_imx)
223 {
224 unsigned int temp = 0;
225
226 if (!i2c_imx->stopped) {
227 /* Stop I2C transaction */
228 dev_dbg(&i2c_imx->adapter.dev, "<%s>\n", __func__);
229 temp = readb(i2c_imx->base + IMX_I2C_I2CR);
230 temp &= ~(I2CR_MSTA | I2CR_MTX);
231 writeb(temp, i2c_imx->base + IMX_I2C_I2CR);
232 }
233 if (cpu_is_mx1()) {
234 /*
235 * This delay caused by an i.MXL hardware bug.
236 * If no (or too short) delay, no "STOP" bit will be generated.
237 */
238 udelay(i2c_imx->disable_delay);
239 }
240
241 if (!i2c_imx->stopped) {
242 i2c_imx_bus_busy(i2c_imx, 0);
243 i2c_imx->stopped = 1;
244 }
245
246 /* Disable I2C controller */
247 writeb(0, i2c_imx->base + IMX_I2C_I2CR);
248 clk_disable(i2c_imx->clk);
249 }
250
251 static void __init i2c_imx_set_clk(struct imx_i2c_struct *i2c_imx,
252 unsigned int rate)
253 {
254 unsigned int i2c_clk_rate;
255 unsigned int div;
256 int i;
257
258 /* Divider value calculation */
259 i2c_clk_rate = clk_get_rate(i2c_imx->clk);
260 div = (i2c_clk_rate + rate - 1) / rate;
261 if (div < i2c_clk_div[0][0])
262 i = 0;
263 else if (div > i2c_clk_div[ARRAY_SIZE(i2c_clk_div) - 1][0])
264 i = ARRAY_SIZE(i2c_clk_div) - 1;
265 else
266 for (i = 0; i2c_clk_div[i][0] < div; i++);
267
268 /* Store divider value */
269 i2c_imx->ifdr = i2c_clk_div[i][1];
270
271 /*
272 * There dummy delay is calculated.
273 * It should be about one I2C clock period long.
274 * This delay is used in I2C bus disable function
275 * to fix chip hardware bug.
276 */
277 i2c_imx->disable_delay = (500000U * i2c_clk_div[i][0]
278 + (i2c_clk_rate / 2) - 1) / (i2c_clk_rate / 2);
279
280 /* dev_dbg() can't be used, because adapter is not yet registered */
281 #ifdef CONFIG_I2C_DEBUG_BUS
282 printk(KERN_DEBUG "I2C: <%s> I2C_CLK=%d, REQ DIV=%d\n",
283 __func__, i2c_clk_rate, div);
284 printk(KERN_DEBUG "I2C: <%s> IFDR[IC]=0x%x, REAL DIV=%d\n",
285 __func__, i2c_clk_div[i][1], i2c_clk_div[i][0]);
286 #endif
287 }
288
289 static irqreturn_t i2c_imx_isr(int irq, void *dev_id)
290 {
291 struct imx_i2c_struct *i2c_imx = dev_id;
292 unsigned int temp;
293
294 temp = readb(i2c_imx->base + IMX_I2C_I2SR);
295 if (temp & I2SR_IIF) {
296 /* save status register */
297 i2c_imx->i2csr = temp;
298 temp &= ~I2SR_IIF;
299 writeb(temp, i2c_imx->base + IMX_I2C_I2SR);
300 wake_up(&i2c_imx->queue);
301 return IRQ_HANDLED;
302 }
303
304 return IRQ_NONE;
305 }
306
307 static int i2c_imx_write(struct imx_i2c_struct *i2c_imx, struct i2c_msg *msgs)
308 {
309 int i, result;
310
311 dev_dbg(&i2c_imx->adapter.dev, "<%s> write slave address: addr=0x%x\n",
312 __func__, msgs->addr << 1);
313
314 /* write slave address */
315 writeb(msgs->addr << 1, i2c_imx->base + IMX_I2C_I2DR);
316 result = i2c_imx_trx_complete(i2c_imx);
317 if (result)
318 return result;
319 result = i2c_imx_acked(i2c_imx);
320 if (result)
321 return result;
322 dev_dbg(&i2c_imx->adapter.dev, "<%s> write data\n", __func__);
323
324 /* write data */
325 for (i = 0; i < msgs->len; i++) {
326 dev_dbg(&i2c_imx->adapter.dev,
327 "<%s> write byte: B%d=0x%X\n",
328 __func__, i, msgs->buf[i]);
329 writeb(msgs->buf[i], i2c_imx->base + IMX_I2C_I2DR);
330 result = i2c_imx_trx_complete(i2c_imx);
331 if (result)
332 return result;
333 result = i2c_imx_acked(i2c_imx);
334 if (result)
335 return result;
336 }
337 return 0;
338 }
339
340 static int i2c_imx_read(struct imx_i2c_struct *i2c_imx, struct i2c_msg *msgs)
341 {
342 int i, result;
343 unsigned int temp;
344
345 dev_dbg(&i2c_imx->adapter.dev,
346 "<%s> write slave address: addr=0x%x\n",
347 __func__, (msgs->addr << 1) | 0x01);
348
349 /* write slave address */
350 writeb((msgs->addr << 1) | 0x01, i2c_imx->base + IMX_I2C_I2DR);
351 result = i2c_imx_trx_complete(i2c_imx);
352 if (result)
353 return result;
354 result = i2c_imx_acked(i2c_imx);
355 if (result)
356 return result;
357
358 dev_dbg(&i2c_imx->adapter.dev, "<%s> setup bus\n", __func__);
359
360 /* setup bus to read data */
361 temp = readb(i2c_imx->base + IMX_I2C_I2CR);
362 temp &= ~I2CR_MTX;
363 if (msgs->len - 1)
364 temp &= ~I2CR_TXAK;
365 writeb(temp, i2c_imx->base + IMX_I2C_I2CR);
366 readb(i2c_imx->base + IMX_I2C_I2DR); /* dummy read */
367
368 dev_dbg(&i2c_imx->adapter.dev, "<%s> read data\n", __func__);
369
370 /* read data */
371 for (i = 0; i < msgs->len; i++) {
372 result = i2c_imx_trx_complete(i2c_imx);
373 if (result)
374 return result;
375 if (i == (msgs->len - 1)) {
376 /* It must generate STOP before read I2DR to prevent
377 controller from generating another clock cycle */
378 dev_dbg(&i2c_imx->adapter.dev,
379 "<%s> clear MSTA\n", __func__);
380 temp = readb(i2c_imx->base + IMX_I2C_I2CR);
381 temp &= ~(I2CR_MSTA | I2CR_MTX);
382 writeb(temp, i2c_imx->base + IMX_I2C_I2CR);
383 i2c_imx_bus_busy(i2c_imx, 0);
384 i2c_imx->stopped = 1;
385 } else if (i == (msgs->len - 2)) {
386 dev_dbg(&i2c_imx->adapter.dev,
387 "<%s> set TXAK\n", __func__);
388 temp = readb(i2c_imx->base + IMX_I2C_I2CR);
389 temp |= I2CR_TXAK;
390 writeb(temp, i2c_imx->base + IMX_I2C_I2CR);
391 }
392 msgs->buf[i] = readb(i2c_imx->base + IMX_I2C_I2DR);
393 dev_dbg(&i2c_imx->adapter.dev,
394 "<%s> read byte: B%d=0x%X\n",
395 __func__, i, msgs->buf[i]);
396 }
397 return 0;
398 }
399
400 static int i2c_imx_xfer(struct i2c_adapter *adapter,
401 struct i2c_msg *msgs, int num)
402 {
403 unsigned int i, temp;
404 int result;
405 struct imx_i2c_struct *i2c_imx = i2c_get_adapdata(adapter);
406
407 dev_dbg(&i2c_imx->adapter.dev, "<%s>\n", __func__);
408
409 /* Start I2C transfer */
410 result = i2c_imx_start(i2c_imx);
411 if (result)
412 goto fail0;
413
414 /* read/write data */
415 for (i = 0; i < num; i++) {
416 if (i) {
417 dev_dbg(&i2c_imx->adapter.dev,
418 "<%s> repeated start\n", __func__);
419 temp = readb(i2c_imx->base + IMX_I2C_I2CR);
420 temp |= I2CR_RSTA;
421 writeb(temp, i2c_imx->base + IMX_I2C_I2CR);
422 result = i2c_imx_bus_busy(i2c_imx, 1);
423 if (result)
424 goto fail0;
425 }
426 dev_dbg(&i2c_imx->adapter.dev,
427 "<%s> transfer message: %d\n", __func__, i);
428 /* write/read data */
429 #ifdef CONFIG_I2C_DEBUG_BUS
430 temp = readb(i2c_imx->base + IMX_I2C_I2CR);
431 dev_dbg(&i2c_imx->adapter.dev, "<%s> CONTROL: IEN=%d, IIEN=%d, "
432 "MSTA=%d, MTX=%d, TXAK=%d, RSTA=%d\n", __func__,
433 (temp & I2CR_IEN ? 1 : 0), (temp & I2CR_IIEN ? 1 : 0),
434 (temp & I2CR_MSTA ? 1 : 0), (temp & I2CR_MTX ? 1 : 0),
435 (temp & I2CR_TXAK ? 1 : 0), (temp & I2CR_RSTA ? 1 : 0));
436 temp = readb(i2c_imx->base + IMX_I2C_I2SR);
437 dev_dbg(&i2c_imx->adapter.dev,
438 "<%s> STATUS: ICF=%d, IAAS=%d, IBB=%d, "
439 "IAL=%d, SRW=%d, IIF=%d, RXAK=%d\n", __func__,
440 (temp & I2SR_ICF ? 1 : 0), (temp & I2SR_IAAS ? 1 : 0),
441 (temp & I2SR_IBB ? 1 : 0), (temp & I2SR_IAL ? 1 : 0),
442 (temp & I2SR_SRW ? 1 : 0), (temp & I2SR_IIF ? 1 : 0),
443 (temp & I2SR_RXAK ? 1 : 0));
444 #endif
445 if (msgs[i].flags & I2C_M_RD)
446 result = i2c_imx_read(i2c_imx, &msgs[i]);
447 else
448 result = i2c_imx_write(i2c_imx, &msgs[i]);
449 if (result)
450 goto fail0;
451 }
452
453 fail0:
454 /* Stop I2C transfer */
455 i2c_imx_stop(i2c_imx);
456
457 dev_dbg(&i2c_imx->adapter.dev, "<%s> exit with: %s: %d\n", __func__,
458 (result < 0) ? "error" : "success msg",
459 (result < 0) ? result : num);
460 return (result < 0) ? result : num;
461 }
462
463 static u32 i2c_imx_func(struct i2c_adapter *adapter)
464 {
465 return I2C_FUNC_I2C | I2C_FUNC_SMBUS_EMUL;
466 }
467
468 static struct i2c_algorithm i2c_imx_algo = {
469 .master_xfer = i2c_imx_xfer,
470 .functionality = i2c_imx_func,
471 };
472
473 static int __init i2c_imx_probe(struct platform_device *pdev)
474 {
475 struct imx_i2c_struct *i2c_imx;
476 struct resource *res;
477 struct imxi2c_platform_data *pdata = pdev->dev.platform_data;
478 void __iomem *base;
479 resource_size_t res_size;
480 int irq, bitrate;
481 int ret;
482
483 dev_dbg(&pdev->dev, "<%s>\n", __func__);
484
485 res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
486 if (!res) {
487 dev_err(&pdev->dev, "can't get device resources\n");
488 return -ENOENT;
489 }
490 irq = platform_get_irq(pdev, 0);
491 if (irq < 0) {
492 dev_err(&pdev->dev, "can't get irq number\n");
493 return -ENOENT;
494 }
495
496 res_size = resource_size(res);
497
498 if (!request_mem_region(res->start, res_size, DRIVER_NAME)) {
499 dev_err(&pdev->dev, "request_mem_region failed\n");
500 return -EBUSY;
501 }
502
503 base = ioremap(res->start, res_size);
504 if (!base) {
505 dev_err(&pdev->dev, "ioremap failed\n");
506 ret = -EIO;
507 goto fail1;
508 }
509
510 i2c_imx = kzalloc(sizeof(struct imx_i2c_struct), GFP_KERNEL);
511 if (!i2c_imx) {
512 dev_err(&pdev->dev, "can't allocate interface\n");
513 ret = -ENOMEM;
514 goto fail2;
515 }
516
517 /* Setup i2c_imx driver structure */
518 strcpy(i2c_imx->adapter.name, pdev->name);
519 i2c_imx->adapter.owner = THIS_MODULE;
520 i2c_imx->adapter.algo = &i2c_imx_algo;
521 i2c_imx->adapter.dev.parent = &pdev->dev;
522 i2c_imx->adapter.nr = pdev->id;
523 i2c_imx->adapter.dev.of_node = pdev->dev.of_node;
524 i2c_imx->irq = irq;
525 i2c_imx->base = base;
526 i2c_imx->res = res;
527
528 /* Get I2C clock */
529 i2c_imx->clk = clk_get(&pdev->dev, "i2c_clk");
530 if (IS_ERR(i2c_imx->clk)) {
531 ret = PTR_ERR(i2c_imx->clk);
532 dev_err(&pdev->dev, "can't get I2C clock\n");
533 goto fail3;
534 }
535
536 /* Request IRQ */
537 ret = request_irq(i2c_imx->irq, i2c_imx_isr, 0, pdev->name, i2c_imx);
538 if (ret) {
539 dev_err(&pdev->dev, "can't claim irq %d\n", i2c_imx->irq);
540 goto fail4;
541 }
542
543 /* Init queue */
544 init_waitqueue_head(&i2c_imx->queue);
545
546 /* Set up adapter data */
547 i2c_set_adapdata(&i2c_imx->adapter, i2c_imx);
548
549 /* Set up clock divider */
550 bitrate = IMX_I2C_BIT_RATE;
551 ret = of_property_read_u32(pdev->dev.of_node,
552 "clock-frequency", &bitrate);
553 if (ret < 0 && pdata && pdata->bitrate)
554 bitrate = pdata->bitrate;
555 i2c_imx_set_clk(i2c_imx, bitrate);
556
557 /* Set up chip registers to defaults */
558 writeb(0, i2c_imx->base + IMX_I2C_I2CR);
559 writeb(0, i2c_imx->base + IMX_I2C_I2SR);
560
561 /* Add I2C adapter */
562 ret = i2c_add_numbered_adapter(&i2c_imx->adapter);
563 if (ret < 0) {
564 dev_err(&pdev->dev, "registration failed\n");
565 goto fail5;
566 }
567
568 of_i2c_register_devices(&i2c_imx->adapter);
569
570 /* Set up platform driver data */
571 platform_set_drvdata(pdev, i2c_imx);
572
573 dev_dbg(&i2c_imx->adapter.dev, "claimed irq %d\n", i2c_imx->irq);
574 dev_dbg(&i2c_imx->adapter.dev, "device resources from 0x%x to 0x%x\n",
575 i2c_imx->res->start, i2c_imx->res->end);
576 dev_dbg(&i2c_imx->adapter.dev, "allocated %d bytes at 0x%x \n",
577 res_size, i2c_imx->res->start);
578 dev_dbg(&i2c_imx->adapter.dev, "adapter name: \"%s\"\n",
579 i2c_imx->adapter.name);
580 dev_dbg(&i2c_imx->adapter.dev, "IMX I2C adapter registered\n");
581
582 return 0; /* Return OK */
583
584 fail5:
585 free_irq(i2c_imx->irq, i2c_imx);
586 fail4:
587 clk_put(i2c_imx->clk);
588 fail3:
589 kfree(i2c_imx);
590 fail2:
591 iounmap(base);
592 fail1:
593 release_mem_region(res->start, resource_size(res));
594 return ret; /* Return error number */
595 }
596
597 static int __exit i2c_imx_remove(struct platform_device *pdev)
598 {
599 struct imx_i2c_struct *i2c_imx = platform_get_drvdata(pdev);
600
601 /* remove adapter */
602 dev_dbg(&i2c_imx->adapter.dev, "adapter removed\n");
603 i2c_del_adapter(&i2c_imx->adapter);
604 platform_set_drvdata(pdev, NULL);
605
606 /* free interrupt */
607 free_irq(i2c_imx->irq, i2c_imx);
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 clk_put(i2c_imx->clk);
616
617 iounmap(i2c_imx->base);
618 release_mem_region(i2c_imx->res->start, resource_size(i2c_imx->res));
619 kfree(i2c_imx);
620 return 0;
621 }
622
623 static struct platform_driver i2c_imx_driver = {
624 .remove = __exit_p(i2c_imx_remove),
625 .driver = {
626 .name = DRIVER_NAME,
627 .owner = THIS_MODULE,
628 .of_match_table = i2c_imx_dt_ids,
629 }
630 };
631
632 static int __init i2c_adap_imx_init(void)
633 {
634 return platform_driver_probe(&i2c_imx_driver, i2c_imx_probe);
635 }
636 subsys_initcall(i2c_adap_imx_init);
637
638 static void __exit i2c_adap_imx_exit(void)
639 {
640 platform_driver_unregister(&i2c_imx_driver);
641 }
642 module_exit(i2c_adap_imx_exit);
643
644 MODULE_LICENSE("GPL");
645 MODULE_AUTHOR("Darius Augulis");
646 MODULE_DESCRIPTION("I2C adapter driver for IMX I2C bus");
647 MODULE_ALIAS("platform:" DRIVER_NAME);