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awilliam
GitHub Repository: awilliam/linux-vfio
Path: blob/master/drivers/i2c/busses/i2c-imx.c
15109 views
1
/*
2
* Copyright (C) 2002 Motorola GSG-China
3
*
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* This program is free software; you can redistribute it and/or
5
* modify it under the terms of the GNU General Public License
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* as published by the Free Software Foundation; either version 2
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* of the License, or (at your option) any later version.
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*
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* 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
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* GNU General Public License for more details.
13
*
14
* You should have received a copy of the GNU General Public License
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* along with this program; if not, write to the Free Software
16
* Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307,
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* USA.
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*
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>
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#include <linux/platform_device.h>
49
#include <linux/clk.h>
50
#include <linux/slab.h>
51
52
#include <mach/irqs.h>
53
#include <mach/hardware.h>
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#include <mach/i2c.h>
55
56
/** Defines ********************************************************************
57
*******************************************************************************/
58
59
/* This will be the driver name the kernel reports */
60
#define DRIVER_NAME "imx-i2c"
61
62
/* Default value */
63
#define IMX_I2C_BIT_RATE 100000 /* 100kHz */
64
65
/* IMX I2C registers */
66
#define IMX_I2C_IADR 0x00 /* i2c slave address */
67
#define IMX_I2C_IFDR 0x04 /* i2c frequency divider */
68
#define IMX_I2C_I2CR 0x08 /* i2c control */
69
#define IMX_I2C_I2SR 0x0C /* i2c status */
70
#define IMX_I2C_I2DR 0x10 /* i2c transfer data */
71
72
/* Bits of IMX I2C registers */
73
#define I2SR_RXAK 0x01
74
#define I2SR_IIF 0x02
75
#define I2SR_SRW 0x04
76
#define I2SR_IAL 0x10
77
#define I2SR_IBB 0x20
78
#define I2SR_IAAS 0x40
79
#define I2SR_ICF 0x80
80
#define I2CR_RSTA 0x04
81
#define I2CR_TXAK 0x08
82
#define I2CR_MTX 0x10
83
#define I2CR_MSTA 0x20
84
#define I2CR_IIEN 0x40
85
#define I2CR_IEN 0x80
86
87
/** Variables ******************************************************************
88
*******************************************************************************/
89
90
/*
91
* sorted list of clock divider, register value pairs
92
* taken from table 26-5, p.26-9, Freescale i.MX
93
* Integrated Portable System Processor Reference Manual
94
* Document Number: MC9328MXLRM, Rev. 5.1, 06/2007
95
*
96
* Duplicated divider values removed from list
97
*/
98
99
static u16 __initdata i2c_clk_div[50][2] = {
100
{ 22, 0x20 }, { 24, 0x21 }, { 26, 0x22 }, { 28, 0x23 },
101
{ 30, 0x00 }, { 32, 0x24 }, { 36, 0x25 }, { 40, 0x26 },
102
{ 42, 0x03 }, { 44, 0x27 }, { 48, 0x28 }, { 52, 0x05 },
103
{ 56, 0x29 }, { 60, 0x06 }, { 64, 0x2A }, { 72, 0x2B },
104
{ 80, 0x2C }, { 88, 0x09 }, { 96, 0x2D }, { 104, 0x0A },
105
{ 112, 0x2E }, { 128, 0x2F }, { 144, 0x0C }, { 160, 0x30 },
106
{ 192, 0x31 }, { 224, 0x32 }, { 240, 0x0F }, { 256, 0x33 },
107
{ 288, 0x10 }, { 320, 0x34 }, { 384, 0x35 }, { 448, 0x36 },
108
{ 480, 0x13 }, { 512, 0x37 }, { 576, 0x14 }, { 640, 0x38 },
109
{ 768, 0x39 }, { 896, 0x3A }, { 960, 0x17 }, { 1024, 0x3B },
110
{ 1152, 0x18 }, { 1280, 0x3C }, { 1536, 0x3D }, { 1792, 0x3E },
111
{ 1920, 0x1B }, { 2048, 0x3F }, { 2304, 0x1C }, { 2560, 0x1D },
112
{ 3072, 0x1E }, { 3840, 0x1F }
113
};
114
115
struct imx_i2c_struct {
116
struct i2c_adapter adapter;
117
struct resource *res;
118
struct clk *clk;
119
void __iomem *base;
120
int irq;
121
wait_queue_head_t queue;
122
unsigned long i2csr;
123
unsigned int disable_delay;
124
int stopped;
125
unsigned int ifdr; /* IMX_I2C_IFDR */
126
};
127
128
/** Functions for IMX I2C adapter driver ***************************************
129
*******************************************************************************/
130
131
static int i2c_imx_bus_busy(struct imx_i2c_struct *i2c_imx, int for_busy)
132
{
133
unsigned long orig_jiffies = jiffies;
134
unsigned int temp;
135
136
dev_dbg(&i2c_imx->adapter.dev, "<%s>\n", __func__);
137
138
while (1) {
139
temp = readb(i2c_imx->base + IMX_I2C_I2SR);
140
if (for_busy && (temp & I2SR_IBB))
141
break;
142
if (!for_busy && !(temp & I2SR_IBB))
143
break;
144
if (signal_pending(current)) {
145
dev_dbg(&i2c_imx->adapter.dev,
146
"<%s> I2C Interrupted\n", __func__);
147
return -EINTR;
148
}
149
if (time_after(jiffies, orig_jiffies + msecs_to_jiffies(500))) {
150
dev_dbg(&i2c_imx->adapter.dev,
151
"<%s> I2C bus is busy\n", __func__);
152
return -ETIMEDOUT;
153
}
154
schedule();
155
}
156
157
return 0;
158
}
159
160
static int i2c_imx_trx_complete(struct imx_i2c_struct *i2c_imx)
161
{
162
wait_event_timeout(i2c_imx->queue, i2c_imx->i2csr & I2SR_IIF, HZ / 10);
163
164
if (unlikely(!(i2c_imx->i2csr & I2SR_IIF))) {
165
dev_dbg(&i2c_imx->adapter.dev, "<%s> Timeout\n", __func__);
166
return -ETIMEDOUT;
167
}
168
dev_dbg(&i2c_imx->adapter.dev, "<%s> TRX complete\n", __func__);
169
i2c_imx->i2csr = 0;
170
return 0;
171
}
172
173
static int i2c_imx_acked(struct imx_i2c_struct *i2c_imx)
174
{
175
if (readb(i2c_imx->base + IMX_I2C_I2SR) & I2SR_RXAK) {
176
dev_dbg(&i2c_imx->adapter.dev, "<%s> No ACK\n", __func__);
177
return -EIO; /* No ACK */
178
}
179
180
dev_dbg(&i2c_imx->adapter.dev, "<%s> ACK received\n", __func__);
181
return 0;
182
}
183
184
static int i2c_imx_start(struct imx_i2c_struct *i2c_imx)
185
{
186
unsigned int temp = 0;
187
int result;
188
189
dev_dbg(&i2c_imx->adapter.dev, "<%s>\n", __func__);
190
191
clk_enable(i2c_imx->clk);
192
writeb(i2c_imx->ifdr, i2c_imx->base + IMX_I2C_IFDR);
193
/* Enable I2C controller */
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writeb(0, i2c_imx->base + IMX_I2C_I2SR);
195
writeb(I2CR_IEN, i2c_imx->base + IMX_I2C_I2CR);
196
197
/* Wait controller to be stable */
198
udelay(50);
199
200
/* Start I2C transaction */
201
temp = readb(i2c_imx->base + IMX_I2C_I2CR);
202
temp |= I2CR_MSTA;
203
writeb(temp, i2c_imx->base + IMX_I2C_I2CR);
204
result = i2c_imx_bus_busy(i2c_imx, 1);
205
if (result)
206
return result;
207
i2c_imx->stopped = 0;
208
209
temp |= I2CR_IIEN | I2CR_MTX | I2CR_TXAK;
210
writeb(temp, i2c_imx->base + IMX_I2C_I2CR);
211
return result;
212
}
213
214
static void i2c_imx_stop(struct imx_i2c_struct *i2c_imx)
215
{
216
unsigned int temp = 0;
217
218
if (!i2c_imx->stopped) {
219
/* Stop I2C transaction */
220
dev_dbg(&i2c_imx->adapter.dev, "<%s>\n", __func__);
221
temp = readb(i2c_imx->base + IMX_I2C_I2CR);
222
temp &= ~(I2CR_MSTA | I2CR_MTX);
223
writeb(temp, i2c_imx->base + IMX_I2C_I2CR);
224
}
225
if (cpu_is_mx1()) {
226
/*
227
* This delay caused by an i.MXL hardware bug.
228
* If no (or too short) delay, no "STOP" bit will be generated.
229
*/
230
udelay(i2c_imx->disable_delay);
231
}
232
233
if (!i2c_imx->stopped) {
234
i2c_imx_bus_busy(i2c_imx, 0);
235
i2c_imx->stopped = 1;
236
}
237
238
/* Disable I2C controller */
239
writeb(0, i2c_imx->base + IMX_I2C_I2CR);
240
clk_disable(i2c_imx->clk);
241
}
242
243
static void __init i2c_imx_set_clk(struct imx_i2c_struct *i2c_imx,
244
unsigned int rate)
245
{
246
unsigned int i2c_clk_rate;
247
unsigned int div;
248
int i;
249
250
/* Divider value calculation */
251
i2c_clk_rate = clk_get_rate(i2c_imx->clk);
252
div = (i2c_clk_rate + rate - 1) / rate;
253
if (div < i2c_clk_div[0][0])
254
i = 0;
255
else if (div > i2c_clk_div[ARRAY_SIZE(i2c_clk_div) - 1][0])
256
i = ARRAY_SIZE(i2c_clk_div) - 1;
257
else
258
for (i = 0; i2c_clk_div[i][0] < div; i++);
259
260
/* Store divider value */
261
i2c_imx->ifdr = i2c_clk_div[i][1];
262
263
/*
264
* There dummy delay is calculated.
265
* It should be about one I2C clock period long.
266
* This delay is used in I2C bus disable function
267
* to fix chip hardware bug.
268
*/
269
i2c_imx->disable_delay = (500000U * i2c_clk_div[i][0]
270
+ (i2c_clk_rate / 2) - 1) / (i2c_clk_rate / 2);
271
272
/* dev_dbg() can't be used, because adapter is not yet registered */
273
#ifdef CONFIG_I2C_DEBUG_BUS
274
printk(KERN_DEBUG "I2C: <%s> I2C_CLK=%d, REQ DIV=%d\n",
275
__func__, i2c_clk_rate, div);
276
printk(KERN_DEBUG "I2C: <%s> IFDR[IC]=0x%x, REAL DIV=%d\n",
277
__func__, i2c_clk_div[i][1], i2c_clk_div[i][0]);
278
#endif
279
}
280
281
static irqreturn_t i2c_imx_isr(int irq, void *dev_id)
282
{
283
struct imx_i2c_struct *i2c_imx = dev_id;
284
unsigned int temp;
285
286
temp = readb(i2c_imx->base + IMX_I2C_I2SR);
287
if (temp & I2SR_IIF) {
288
/* save status register */
289
i2c_imx->i2csr = temp;
290
temp &= ~I2SR_IIF;
291
writeb(temp, i2c_imx->base + IMX_I2C_I2SR);
292
wake_up(&i2c_imx->queue);
293
return IRQ_HANDLED;
294
}
295
296
return IRQ_NONE;
297
}
298
299
static int i2c_imx_write(struct imx_i2c_struct *i2c_imx, struct i2c_msg *msgs)
300
{
301
int i, result;
302
303
dev_dbg(&i2c_imx->adapter.dev, "<%s> write slave address: addr=0x%x\n",
304
__func__, msgs->addr << 1);
305
306
/* write slave address */
307
writeb(msgs->addr << 1, i2c_imx->base + IMX_I2C_I2DR);
308
result = i2c_imx_trx_complete(i2c_imx);
309
if (result)
310
return result;
311
result = i2c_imx_acked(i2c_imx);
312
if (result)
313
return result;
314
dev_dbg(&i2c_imx->adapter.dev, "<%s> write data\n", __func__);
315
316
/* write data */
317
for (i = 0; i < msgs->len; i++) {
318
dev_dbg(&i2c_imx->adapter.dev,
319
"<%s> write byte: B%d=0x%X\n",
320
__func__, i, msgs->buf[i]);
321
writeb(msgs->buf[i], i2c_imx->base + IMX_I2C_I2DR);
322
result = i2c_imx_trx_complete(i2c_imx);
323
if (result)
324
return result;
325
result = i2c_imx_acked(i2c_imx);
326
if (result)
327
return result;
328
}
329
return 0;
330
}
331
332
static int i2c_imx_read(struct imx_i2c_struct *i2c_imx, struct i2c_msg *msgs)
333
{
334
int i, result;
335
unsigned int temp;
336
337
dev_dbg(&i2c_imx->adapter.dev,
338
"<%s> write slave address: addr=0x%x\n",
339
__func__, (msgs->addr << 1) | 0x01);
340
341
/* write slave address */
342
writeb((msgs->addr << 1) | 0x01, i2c_imx->base + IMX_I2C_I2DR);
343
result = i2c_imx_trx_complete(i2c_imx);
344
if (result)
345
return result;
346
result = i2c_imx_acked(i2c_imx);
347
if (result)
348
return result;
349
350
dev_dbg(&i2c_imx->adapter.dev, "<%s> setup bus\n", __func__);
351
352
/* setup bus to read data */
353
temp = readb(i2c_imx->base + IMX_I2C_I2CR);
354
temp &= ~I2CR_MTX;
355
if (msgs->len - 1)
356
temp &= ~I2CR_TXAK;
357
writeb(temp, i2c_imx->base + IMX_I2C_I2CR);
358
readb(i2c_imx->base + IMX_I2C_I2DR); /* dummy read */
359
360
dev_dbg(&i2c_imx->adapter.dev, "<%s> read data\n", __func__);
361
362
/* read data */
363
for (i = 0; i < msgs->len; i++) {
364
result = i2c_imx_trx_complete(i2c_imx);
365
if (result)
366
return result;
367
if (i == (msgs->len - 1)) {
368
/* It must generate STOP before read I2DR to prevent
369
controller from generating another clock cycle */
370
dev_dbg(&i2c_imx->adapter.dev,
371
"<%s> clear MSTA\n", __func__);
372
temp = readb(i2c_imx->base + IMX_I2C_I2CR);
373
temp &= ~(I2CR_MSTA | I2CR_MTX);
374
writeb(temp, i2c_imx->base + IMX_I2C_I2CR);
375
i2c_imx_bus_busy(i2c_imx, 0);
376
i2c_imx->stopped = 1;
377
} else if (i == (msgs->len - 2)) {
378
dev_dbg(&i2c_imx->adapter.dev,
379
"<%s> set TXAK\n", __func__);
380
temp = readb(i2c_imx->base + IMX_I2C_I2CR);
381
temp |= I2CR_TXAK;
382
writeb(temp, i2c_imx->base + IMX_I2C_I2CR);
383
}
384
msgs->buf[i] = readb(i2c_imx->base + IMX_I2C_I2DR);
385
dev_dbg(&i2c_imx->adapter.dev,
386
"<%s> read byte: B%d=0x%X\n",
387
__func__, i, msgs->buf[i]);
388
}
389
return 0;
390
}
391
392
static int i2c_imx_xfer(struct i2c_adapter *adapter,
393
struct i2c_msg *msgs, int num)
394
{
395
unsigned int i, temp;
396
int result;
397
struct imx_i2c_struct *i2c_imx = i2c_get_adapdata(adapter);
398
399
dev_dbg(&i2c_imx->adapter.dev, "<%s>\n", __func__);
400
401
/* Start I2C transfer */
402
result = i2c_imx_start(i2c_imx);
403
if (result)
404
goto fail0;
405
406
/* read/write data */
407
for (i = 0; i < num; i++) {
408
if (i) {
409
dev_dbg(&i2c_imx->adapter.dev,
410
"<%s> repeated start\n", __func__);
411
temp = readb(i2c_imx->base + IMX_I2C_I2CR);
412
temp |= I2CR_RSTA;
413
writeb(temp, i2c_imx->base + IMX_I2C_I2CR);
414
result = i2c_imx_bus_busy(i2c_imx, 1);
415
if (result)
416
goto fail0;
417
}
418
dev_dbg(&i2c_imx->adapter.dev,
419
"<%s> transfer message: %d\n", __func__, i);
420
/* write/read data */
421
#ifdef CONFIG_I2C_DEBUG_BUS
422
temp = readb(i2c_imx->base + IMX_I2C_I2CR);
423
dev_dbg(&i2c_imx->adapter.dev, "<%s> CONTROL: IEN=%d, IIEN=%d, "
424
"MSTA=%d, MTX=%d, TXAK=%d, RSTA=%d\n", __func__,
425
(temp & I2CR_IEN ? 1 : 0), (temp & I2CR_IIEN ? 1 : 0),
426
(temp & I2CR_MSTA ? 1 : 0), (temp & I2CR_MTX ? 1 : 0),
427
(temp & I2CR_TXAK ? 1 : 0), (temp & I2CR_RSTA ? 1 : 0));
428
temp = readb(i2c_imx->base + IMX_I2C_I2SR);
429
dev_dbg(&i2c_imx->adapter.dev,
430
"<%s> STATUS: ICF=%d, IAAS=%d, IBB=%d, "
431
"IAL=%d, SRW=%d, IIF=%d, RXAK=%d\n", __func__,
432
(temp & I2SR_ICF ? 1 : 0), (temp & I2SR_IAAS ? 1 : 0),
433
(temp & I2SR_IBB ? 1 : 0), (temp & I2SR_IAL ? 1 : 0),
434
(temp & I2SR_SRW ? 1 : 0), (temp & I2SR_IIF ? 1 : 0),
435
(temp & I2SR_RXAK ? 1 : 0));
436
#endif
437
if (msgs[i].flags & I2C_M_RD)
438
result = i2c_imx_read(i2c_imx, &msgs[i]);
439
else
440
result = i2c_imx_write(i2c_imx, &msgs[i]);
441
if (result)
442
goto fail0;
443
}
444
445
fail0:
446
/* Stop I2C transfer */
447
i2c_imx_stop(i2c_imx);
448
449
dev_dbg(&i2c_imx->adapter.dev, "<%s> exit with: %s: %d\n", __func__,
450
(result < 0) ? "error" : "success msg",
451
(result < 0) ? result : num);
452
return (result < 0) ? result : num;
453
}
454
455
static u32 i2c_imx_func(struct i2c_adapter *adapter)
456
{
457
return I2C_FUNC_I2C | I2C_FUNC_SMBUS_EMUL;
458
}
459
460
static struct i2c_algorithm i2c_imx_algo = {
461
.master_xfer = i2c_imx_xfer,
462
.functionality = i2c_imx_func,
463
};
464
465
static int __init i2c_imx_probe(struct platform_device *pdev)
466
{
467
struct imx_i2c_struct *i2c_imx;
468
struct resource *res;
469
struct imxi2c_platform_data *pdata;
470
void __iomem *base;
471
resource_size_t res_size;
472
int irq;
473
int ret;
474
475
dev_dbg(&pdev->dev, "<%s>\n", __func__);
476
477
res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
478
if (!res) {
479
dev_err(&pdev->dev, "can't get device resources\n");
480
return -ENOENT;
481
}
482
irq = platform_get_irq(pdev, 0);
483
if (irq < 0) {
484
dev_err(&pdev->dev, "can't get irq number\n");
485
return -ENOENT;
486
}
487
488
pdata = pdev->dev.platform_data;
489
490
if (pdata && pdata->init) {
491
ret = pdata->init(&pdev->dev);
492
if (ret)
493
return ret;
494
}
495
496
res_size = resource_size(res);
497
498
if (!request_mem_region(res->start, res_size, DRIVER_NAME)) {
499
ret = -EBUSY;
500
goto fail0;
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->irq = irq;
524
i2c_imx->base = base;
525
i2c_imx->res = res;
526
527
/* Get I2C clock */
528
i2c_imx->clk = clk_get(&pdev->dev, "i2c_clk");
529
if (IS_ERR(i2c_imx->clk)) {
530
ret = PTR_ERR(i2c_imx->clk);
531
dev_err(&pdev->dev, "can't get I2C clock\n");
532
goto fail3;
533
}
534
535
/* Request IRQ */
536
ret = request_irq(i2c_imx->irq, i2c_imx_isr, 0, pdev->name, i2c_imx);
537
if (ret) {
538
dev_err(&pdev->dev, "can't claim irq %d\n", i2c_imx->irq);
539
goto fail4;
540
}
541
542
/* Init queue */
543
init_waitqueue_head(&i2c_imx->queue);
544
545
/* Set up adapter data */
546
i2c_set_adapdata(&i2c_imx->adapter, i2c_imx);
547
548
/* Set up clock divider */
549
if (pdata && pdata->bitrate)
550
i2c_imx_set_clk(i2c_imx, pdata->bitrate);
551
else
552
i2c_imx_set_clk(i2c_imx, IMX_I2C_BIT_RATE);
553
554
/* Set up chip registers to defaults */
555
writeb(0, i2c_imx->base + IMX_I2C_I2CR);
556
writeb(0, i2c_imx->base + IMX_I2C_I2SR);
557
558
/* Add I2C adapter */
559
ret = i2c_add_numbered_adapter(&i2c_imx->adapter);
560
if (ret < 0) {
561
dev_err(&pdev->dev, "registration failed\n");
562
goto fail5;
563
}
564
565
/* Set up platform driver data */
566
platform_set_drvdata(pdev, i2c_imx);
567
568
dev_dbg(&i2c_imx->adapter.dev, "claimed irq %d\n", i2c_imx->irq);
569
dev_dbg(&i2c_imx->adapter.dev, "device resources from 0x%x to 0x%x\n",
570
i2c_imx->res->start, i2c_imx->res->end);
571
dev_dbg(&i2c_imx->adapter.dev, "allocated %d bytes at 0x%x \n",
572
res_size, i2c_imx->res->start);
573
dev_dbg(&i2c_imx->adapter.dev, "adapter name: \"%s\"\n",
574
i2c_imx->adapter.name);
575
dev_dbg(&i2c_imx->adapter.dev, "IMX I2C adapter registered\n");
576
577
return 0; /* Return OK */
578
579
fail5:
580
free_irq(i2c_imx->irq, i2c_imx);
581
fail4:
582
clk_put(i2c_imx->clk);
583
fail3:
584
kfree(i2c_imx);
585
fail2:
586
iounmap(base);
587
fail1:
588
release_mem_region(res->start, resource_size(res));
589
fail0:
590
if (pdata && pdata->exit)
591
pdata->exit(&pdev->dev);
592
return ret; /* Return error number */
593
}
594
595
static int __exit i2c_imx_remove(struct platform_device *pdev)
596
{
597
struct imx_i2c_struct *i2c_imx = platform_get_drvdata(pdev);
598
struct imxi2c_platform_data *pdata = pdev->dev.platform_data;
599
600
/* remove adapter */
601
dev_dbg(&i2c_imx->adapter.dev, "adapter removed\n");
602
i2c_del_adapter(&i2c_imx->adapter);
603
platform_set_drvdata(pdev, NULL);
604
605
/* free interrupt */
606
free_irq(i2c_imx->irq, i2c_imx);
607
608
/* setup chip registers to defaults */
609
writeb(0, i2c_imx->base + IMX_I2C_IADR);
610
writeb(0, i2c_imx->base + IMX_I2C_IFDR);
611
writeb(0, i2c_imx->base + IMX_I2C_I2CR);
612
writeb(0, i2c_imx->base + IMX_I2C_I2SR);
613
614
/* Shut down hardware */
615
if (pdata && pdata->exit)
616
pdata->exit(&pdev->dev);
617
618
clk_put(i2c_imx->clk);
619
620
iounmap(i2c_imx->base);
621
release_mem_region(i2c_imx->res->start, resource_size(i2c_imx->res));
622
kfree(i2c_imx);
623
return 0;
624
}
625
626
static struct platform_driver i2c_imx_driver = {
627
.remove = __exit_p(i2c_imx_remove),
628
.driver = {
629
.name = DRIVER_NAME,
630
.owner = THIS_MODULE,
631
}
632
};
633
634
static int __init i2c_adap_imx_init(void)
635
{
636
return platform_driver_probe(&i2c_imx_driver, i2c_imx_probe);
637
}
638
subsys_initcall(i2c_adap_imx_init);
639
640
static void __exit i2c_adap_imx_exit(void)
641
{
642
platform_driver_unregister(&i2c_imx_driver);
643
}
644
module_exit(i2c_adap_imx_exit);
645
646
MODULE_LICENSE("GPL");
647
MODULE_AUTHOR("Darius Augulis");
648
MODULE_DESCRIPTION("I2C adapter driver for IMX I2C bus");
649
MODULE_ALIAS("platform:" DRIVER_NAME);
650
651