blob: ff284e5afd9587c4e8a14bc9633b018098ce983c [file] [log] [blame]
Andrew Chew3285aae2010-09-08 22:02:17 -07001/*
2 * A sensor driver for the magnetometer AK8975.
3 *
4 * Magnetic compass sensor driver for monitoring magnetic flux information.
5 *
6 * Copyright (c) 2010, NVIDIA Corporation.
7 *
8 * This program is free software; you can redistribute it and/or modify
9 * it under the terms of the GNU General Public License as published by
10 * the Free Software Foundation; either version 2 of the License, or
11 * (at your option) any later version.
12 *
13 * This program is distributed in the hope that it will be useful, but WITHOUT
14 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
15 * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License for
16 * more details.
17 *
18 * You should have received a copy of the GNU General Public License along
19 * with this program; if not, write to the Free Software Foundation, Inc.,
20 * 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA.
21 */
22
23#include <linux/module.h>
24#include <linux/kernel.h>
25#include <linux/slab.h>
26#include <linux/i2c.h>
Jacek Anaszewski94a6d5c2013-05-07 11:41:00 +010027#include <linux/interrupt.h>
Andrew Chew3285aae2010-09-08 22:02:17 -070028#include <linux/err.h>
29#include <linux/mutex.h>
30#include <linux/delay.h>
Jacek Anaszewski94a6d5c2013-05-07 11:41:00 +010031#include <linux/bitops.h>
Andrew Chew3285aae2010-09-08 22:02:17 -070032#include <linux/gpio.h>
Jacek Anaszewskif4b7f752013-05-07 11:41:00 +010033#include <linux/of_gpio.h>
Andrew Chew3285aae2010-09-08 22:02:17 -070034
Jonathan Cameron06458e22012-04-25 15:54:58 +010035#include <linux/iio/iio.h>
36#include <linux/iio/sysfs.h>
Andrew Chew3285aae2010-09-08 22:02:17 -070037/*
38 * Register definitions, as well as various shifts and masks to get at the
39 * individual fields of the registers.
40 */
41#define AK8975_REG_WIA 0x00
42#define AK8975_DEVICE_ID 0x48
43
44#define AK8975_REG_INFO 0x01
45
46#define AK8975_REG_ST1 0x02
47#define AK8975_REG_ST1_DRDY_SHIFT 0
48#define AK8975_REG_ST1_DRDY_MASK (1 << AK8975_REG_ST1_DRDY_SHIFT)
49
50#define AK8975_REG_HXL 0x03
51#define AK8975_REG_HXH 0x04
52#define AK8975_REG_HYL 0x05
53#define AK8975_REG_HYH 0x06
54#define AK8975_REG_HZL 0x07
55#define AK8975_REG_HZH 0x08
56#define AK8975_REG_ST2 0x09
57#define AK8975_REG_ST2_DERR_SHIFT 2
58#define AK8975_REG_ST2_DERR_MASK (1 << AK8975_REG_ST2_DERR_SHIFT)
59
60#define AK8975_REG_ST2_HOFL_SHIFT 3
61#define AK8975_REG_ST2_HOFL_MASK (1 << AK8975_REG_ST2_HOFL_SHIFT)
62
63#define AK8975_REG_CNTL 0x0A
64#define AK8975_REG_CNTL_MODE_SHIFT 0
65#define AK8975_REG_CNTL_MODE_MASK (0xF << AK8975_REG_CNTL_MODE_SHIFT)
66#define AK8975_REG_CNTL_MODE_POWER_DOWN 0
67#define AK8975_REG_CNTL_MODE_ONCE 1
68#define AK8975_REG_CNTL_MODE_SELF_TEST 8
69#define AK8975_REG_CNTL_MODE_FUSE_ROM 0xF
70
71#define AK8975_REG_RSVC 0x0B
72#define AK8975_REG_ASTC 0x0C
73#define AK8975_REG_TS1 0x0D
74#define AK8975_REG_TS2 0x0E
75#define AK8975_REG_I2CDIS 0x0F
76#define AK8975_REG_ASAX 0x10
77#define AK8975_REG_ASAY 0x11
78#define AK8975_REG_ASAZ 0x12
79
80#define AK8975_MAX_REGS AK8975_REG_ASAZ
81
82/*
83 * Miscellaneous values.
84 */
85#define AK8975_MAX_CONVERSION_TIMEOUT 500
86#define AK8975_CONVERSION_DONE_POLL_TIME 10
Jacek Anaszewski94a6d5c2013-05-07 11:41:00 +010087#define AK8975_DATA_READY_TIMEOUT ((100*HZ)/1000)
Andrew Chew3285aae2010-09-08 22:02:17 -070088
89/*
90 * Per-instance context data for the device.
91 */
92struct ak8975_data {
93 struct i2c_client *client;
Andrew Chew3285aae2010-09-08 22:02:17 -070094 struct attribute_group attrs;
95 struct mutex lock;
96 u8 asa[3];
97 long raw_to_gauss[3];
Andrew Chew3285aae2010-09-08 22:02:17 -070098 u8 reg_cache[AK8975_MAX_REGS];
99 int eoc_gpio;
Jacek Anaszewski94a6d5c2013-05-07 11:41:00 +0100100 int eoc_irq;
101 wait_queue_head_t data_ready_queue;
102 unsigned long flags;
Andrew Chew3285aae2010-09-08 22:02:17 -0700103};
104
Jonathan Cameron694e1b52011-08-12 17:48:03 +0100105static const int ak8975_index_to_reg[] = {
106 AK8975_REG_HXL, AK8975_REG_HYL, AK8975_REG_HZL,
107};
108
Andrew Chew3285aae2010-09-08 22:02:17 -0700109/*
110 * Helper function to write to the I2C device's registers.
111 */
112static int ak8975_write_data(struct i2c_client *client,
113 u8 reg, u8 val, u8 mask, u8 shift)
114{
Preetham Chandru40f32d92012-04-09 18:05:01 +0530115 struct iio_dev *indio_dev = i2c_get_clientdata(client);
116 struct ak8975_data *data = iio_priv(indio_dev);
Jonathan Cameron694e1b52011-08-12 17:48:03 +0100117 u8 regval;
118 int ret;
Andrew Chew3285aae2010-09-08 22:02:17 -0700119
Jonathan Cameron694e1b52011-08-12 17:48:03 +0100120 regval = (data->reg_cache[reg] & ~mask) | (val << shift);
121 ret = i2c_smbus_write_byte_data(client, reg, regval);
Andrew Chew3285aae2010-09-08 22:02:17 -0700122 if (ret < 0) {
123 dev_err(&client->dev, "Write to device fails status %x\n", ret);
124 return ret;
125 }
126 data->reg_cache[reg] = regval;
127
128 return 0;
129}
130
131/*
Jacek Anaszewski94a6d5c2013-05-07 11:41:00 +0100132 * Handle data ready irq
133 */
134static irqreturn_t ak8975_irq_handler(int irq, void *data)
135{
136 struct ak8975_data *ak8975 = data;
137
138 set_bit(0, &ak8975->flags);
139 wake_up(&ak8975->data_ready_queue);
140
141 return IRQ_HANDLED;
142}
143
144/*
145 * Install data ready interrupt handler
146 */
147static int ak8975_setup_irq(struct ak8975_data *data)
148{
149 struct i2c_client *client = data->client;
150 int rc;
151 int irq;
152
153 if (client->irq)
154 irq = client->irq;
155 else
156 irq = gpio_to_irq(data->eoc_gpio);
157
158 rc = request_irq(irq, ak8975_irq_handler,
159 IRQF_TRIGGER_RISING | IRQF_ONESHOT,
160 dev_name(&client->dev), data);
161 if (rc < 0) {
162 dev_err(&client->dev,
163 "irq %d request failed, (gpio %d): %d\n",
164 irq, data->eoc_gpio, rc);
165 return rc;
166 }
167
168 init_waitqueue_head(&data->data_ready_queue);
169 clear_bit(0, &data->flags);
170 data->eoc_irq = irq;
171
172 return rc;
173}
174
175
176/*
Andrew Chew3285aae2010-09-08 22:02:17 -0700177 * Perform some start-of-day setup, including reading the asa calibration
178 * values and caching them.
179 */
180static int ak8975_setup(struct i2c_client *client)
181{
Preetham Chandru40f32d92012-04-09 18:05:01 +0530182 struct iio_dev *indio_dev = i2c_get_clientdata(client);
183 struct ak8975_data *data = iio_priv(indio_dev);
Andrew Chew3285aae2010-09-08 22:02:17 -0700184 u8 device_id;
185 int ret;
186
187 /* Confirm that the device we're talking to is really an AK8975. */
Jonathan Cameronc411f602013-03-24 16:58:00 +0000188 ret = i2c_smbus_read_byte_data(client, AK8975_REG_WIA);
Andrew Chew3285aae2010-09-08 22:02:17 -0700189 if (ret < 0) {
190 dev_err(&client->dev, "Error reading WIA\n");
191 return ret;
192 }
Jonathan Cameronc411f602013-03-24 16:58:00 +0000193 device_id = ret;
Andrew Chew3285aae2010-09-08 22:02:17 -0700194 if (device_id != AK8975_DEVICE_ID) {
195 dev_err(&client->dev, "Device ak8975 not found\n");
196 return -ENODEV;
197 }
198
199 /* Write the fused rom access mode. */
200 ret = ak8975_write_data(client,
201 AK8975_REG_CNTL,
202 AK8975_REG_CNTL_MODE_FUSE_ROM,
203 AK8975_REG_CNTL_MODE_MASK,
204 AK8975_REG_CNTL_MODE_SHIFT);
205 if (ret < 0) {
206 dev_err(&client->dev, "Error in setting fuse access mode\n");
207 return ret;
208 }
209
210 /* Get asa data and store in the device data. */
Jonathan Cameronc411f602013-03-24 16:58:00 +0000211 ret = i2c_smbus_read_i2c_block_data(client, AK8975_REG_ASAX,
212 3, data->asa);
Andrew Chew3285aae2010-09-08 22:02:17 -0700213 if (ret < 0) {
214 dev_err(&client->dev, "Not able to read asa data\n");
215 return ret;
216 }
217
Leed Aguilar040f3e52012-06-06 16:14:56 -0400218 /* After reading fuse ROM data set power-down mode */
219 ret = ak8975_write_data(client,
220 AK8975_REG_CNTL,
221 AK8975_REG_CNTL_MODE_POWER_DOWN,
222 AK8975_REG_CNTL_MODE_MASK,
223 AK8975_REG_CNTL_MODE_SHIFT);
Jacek Anaszewski94a6d5c2013-05-07 11:41:00 +0100224
225 if (data->eoc_gpio > 0 || client->irq) {
226 ret = ak8975_setup_irq(data);
227 if (ret < 0) {
228 dev_err(&client->dev,
229 "Error setting data ready interrupt\n");
230 return ret;
231 }
232 }
233
Leed Aguilar040f3e52012-06-06 16:14:56 -0400234 if (ret < 0) {
235 dev_err(&client->dev, "Error in setting power-down mode\n");
236 return ret;
237 }
238
Andrew Chew3285aae2010-09-08 22:02:17 -0700239/*
Jonathan Cameron694e1b52011-08-12 17:48:03 +0100240 * Precalculate scale factor (in Gauss units) for each axis and
241 * store in the device data.
Andrew Chew3285aae2010-09-08 22:02:17 -0700242 *
243 * This scale factor is axis-dependent, and is derived from 3 calibration
244 * factors ASA(x), ASA(y), and ASA(z).
245 *
246 * These ASA values are read from the sensor device at start of day, and
247 * cached in the device context struct.
248 *
249 * Adjusting the flux value with the sensitivity adjustment value should be
250 * done via the following formula:
251 *
252 * Hadj = H * ( ( ( (ASA-128)*0.5 ) / 128 ) + 1 )
253 *
254 * where H is the raw value, ASA is the sensitivity adjustment, and Hadj
255 * is the resultant adjusted value.
256 *
257 * We reduce the formula to:
258 *
259 * Hadj = H * (ASA + 128) / 256
260 *
261 * H is in the range of -4096 to 4095. The magnetometer has a range of
262 * +-1229uT. To go from the raw value to uT is:
263 *
264 * HuT = H * 1229/4096, or roughly, 3/10.
265 *
Peter Meerwaldeb036102013-10-19 18:17:00 +0100266 * Since 1uT = 0.01 gauss, our final scale factor becomes:
Andrew Chew3285aae2010-09-08 22:02:17 -0700267 *
268 * Hadj = H * ((ASA + 128) / 256) * 3/10 * 100
269 * Hadj = H * ((ASA + 128) * 30 / 256
270 *
271 * Since ASA doesn't change, we cache the resultant scale factor into the
272 * device context in ak8975_setup().
273 */
Jonathan Cameron694e1b52011-08-12 17:48:03 +0100274 data->raw_to_gauss[0] = ((data->asa[0] + 128) * 30) >> 8;
275 data->raw_to_gauss[1] = ((data->asa[1] + 128) * 30) >> 8;
276 data->raw_to_gauss[2] = ((data->asa[2] + 128) * 30) >> 8;
277
278 return 0;
279}
280
Alan Cox01fbb472011-04-06 13:31:40 +0100281static int wait_conversion_complete_gpio(struct ak8975_data *data)
282{
283 struct i2c_client *client = data->client;
Alan Cox01fbb472011-04-06 13:31:40 +0100284 u32 timeout_ms = AK8975_MAX_CONVERSION_TIMEOUT;
285 int ret;
286
287 /* Wait for the conversion to complete. */
288 while (timeout_ms) {
289 msleep(AK8975_CONVERSION_DONE_POLL_TIME);
290 if (gpio_get_value(data->eoc_gpio))
291 break;
292 timeout_ms -= AK8975_CONVERSION_DONE_POLL_TIME;
293 }
294 if (!timeout_ms) {
295 dev_err(&client->dev, "Conversion timeout happened\n");
296 return -EINVAL;
297 }
298
Jonathan Cameronc411f602013-03-24 16:58:00 +0000299 ret = i2c_smbus_read_byte_data(client, AK8975_REG_ST1);
300 if (ret < 0)
Alan Cox01fbb472011-04-06 13:31:40 +0100301 dev_err(&client->dev, "Error in reading ST1\n");
Jonathan Cameronc411f602013-03-24 16:58:00 +0000302
303 return ret;
Alan Cox01fbb472011-04-06 13:31:40 +0100304}
305
306static int wait_conversion_complete_polled(struct ak8975_data *data)
307{
308 struct i2c_client *client = data->client;
309 u8 read_status;
310 u32 timeout_ms = AK8975_MAX_CONVERSION_TIMEOUT;
311 int ret;
312
313 /* Wait for the conversion to complete. */
314 while (timeout_ms) {
315 msleep(AK8975_CONVERSION_DONE_POLL_TIME);
Jonathan Cameronc411f602013-03-24 16:58:00 +0000316 ret = i2c_smbus_read_byte_data(client, AK8975_REG_ST1);
Alan Cox01fbb472011-04-06 13:31:40 +0100317 if (ret < 0) {
318 dev_err(&client->dev, "Error in reading ST1\n");
319 return ret;
320 }
Jonathan Cameronc411f602013-03-24 16:58:00 +0000321 read_status = ret;
Alan Cox01fbb472011-04-06 13:31:40 +0100322 if (read_status)
323 break;
324 timeout_ms -= AK8975_CONVERSION_DONE_POLL_TIME;
325 }
326 if (!timeout_ms) {
327 dev_err(&client->dev, "Conversion timeout happened\n");
328 return -EINVAL;
329 }
Jacek Anaszewski94a6d5c2013-05-07 11:41:00 +0100330
Alan Cox01fbb472011-04-06 13:31:40 +0100331 return read_status;
332}
333
Jacek Anaszewski94a6d5c2013-05-07 11:41:00 +0100334/* Returns 0 if the end of conversion interrupt occured or -ETIME otherwise */
335static int wait_conversion_complete_interrupt(struct ak8975_data *data)
336{
337 int ret;
338
339 ret = wait_event_timeout(data->data_ready_queue,
340 test_bit(0, &data->flags),
341 AK8975_DATA_READY_TIMEOUT);
342 clear_bit(0, &data->flags);
343
344 return ret > 0 ? 0 : -ETIME;
345}
346
Andrew Chew3285aae2010-09-08 22:02:17 -0700347/*
348 * Emits the raw flux value for the x, y, or z axis.
349 */
Jonathan Cameron694e1b52011-08-12 17:48:03 +0100350static int ak8975_read_axis(struct iio_dev *indio_dev, int index, int *val)
Andrew Chew3285aae2010-09-08 22:02:17 -0700351{
Jonathan Cameron338473c2011-06-27 13:07:54 +0100352 struct ak8975_data *data = iio_priv(indio_dev);
Andrew Chew3285aae2010-09-08 22:02:17 -0700353 struct i2c_client *client = data->client;
Andrew Chew3285aae2010-09-08 22:02:17 -0700354 u16 meas_reg;
355 s16 raw;
Andrew Chew3285aae2010-09-08 22:02:17 -0700356 int ret;
357
358 mutex_lock(&data->lock);
359
Andrew Chew3285aae2010-09-08 22:02:17 -0700360 /* Set up the device for taking a sample. */
361 ret = ak8975_write_data(client,
362 AK8975_REG_CNTL,
363 AK8975_REG_CNTL_MODE_ONCE,
364 AK8975_REG_CNTL_MODE_MASK,
365 AK8975_REG_CNTL_MODE_SHIFT);
366 if (ret < 0) {
367 dev_err(&client->dev, "Error in setting operating mode\n");
368 goto exit;
369 }
370
371 /* Wait for the conversion to complete. */
Jacek Anaszewski94a6d5c2013-05-07 11:41:00 +0100372 if (data->eoc_irq)
373 ret = wait_conversion_complete_interrupt(data);
374 else if (gpio_is_valid(data->eoc_gpio))
Alan Cox01fbb472011-04-06 13:31:40 +0100375 ret = wait_conversion_complete_gpio(data);
376 else
377 ret = wait_conversion_complete_polled(data);
378 if (ret < 0)
Andrew Chew3285aae2010-09-08 22:02:17 -0700379 goto exit;
Andrew Chew3285aae2010-09-08 22:02:17 -0700380
Jacek Anaszewski94a6d5c2013-05-07 11:41:00 +0100381 /* This will be executed only for non-interrupt based waiting case */
Jonathan Cameronc411f602013-03-24 16:58:00 +0000382 if (ret & AK8975_REG_ST1_DRDY_MASK) {
383 ret = i2c_smbus_read_byte_data(client, AK8975_REG_ST2);
Andrew Chew3285aae2010-09-08 22:02:17 -0700384 if (ret < 0) {
385 dev_err(&client->dev, "Error in reading ST2\n");
386 goto exit;
387 }
Jonathan Cameronc411f602013-03-24 16:58:00 +0000388 if (ret & (AK8975_REG_ST2_DERR_MASK |
389 AK8975_REG_ST2_HOFL_MASK)) {
390 dev_err(&client->dev, "ST2 status error 0x%x\n", ret);
Andrew Chew3285aae2010-09-08 22:02:17 -0700391 ret = -EINVAL;
392 goto exit;
393 }
394 }
395
396 /* Read the flux value from the appropriate register
397 (the register is specified in the iio device attributes). */
Jonathan Cameronc411f602013-03-24 16:58:00 +0000398 ret = i2c_smbus_read_word_data(client, ak8975_index_to_reg[index]);
Andrew Chew3285aae2010-09-08 22:02:17 -0700399 if (ret < 0) {
400 dev_err(&client->dev, "Read axis data fails\n");
401 goto exit;
402 }
Jonathan Cameronc411f602013-03-24 16:58:00 +0000403 meas_reg = ret;
Andrew Chew3285aae2010-09-08 22:02:17 -0700404
405 mutex_unlock(&data->lock);
406
407 /* Endian conversion of the measured values. */
408 raw = (s16) (le16_to_cpu(meas_reg));
409
410 /* Clamp to valid range. */
411 raw = clamp_t(s16, raw, -4096, 4095);
Jonathan Cameron694e1b52011-08-12 17:48:03 +0100412 *val = raw;
413 return IIO_VAL_INT;
Andrew Chew3285aae2010-09-08 22:02:17 -0700414
415exit:
416 mutex_unlock(&data->lock);
417 return ret;
418}
419
Jonathan Cameron694e1b52011-08-12 17:48:03 +0100420static int ak8975_read_raw(struct iio_dev *indio_dev,
421 struct iio_chan_spec const *chan,
422 int *val, int *val2,
423 long mask)
424{
425 struct ak8975_data *data = iio_priv(indio_dev);
426
427 switch (mask) {
Jonathan Cameron4d9948b2012-04-15 17:41:23 +0100428 case IIO_CHAN_INFO_RAW:
Jonathan Cameron694e1b52011-08-12 17:48:03 +0100429 return ak8975_read_axis(indio_dev, chan->address, val);
Jonathan Cameronc8a9f802011-10-26 17:41:36 +0100430 case IIO_CHAN_INFO_SCALE:
Jonathan Cameron694e1b52011-08-12 17:48:03 +0100431 *val = data->raw_to_gauss[chan->address];
432 return IIO_VAL_INT;
433 }
434 return -EINVAL;
435}
436
437#define AK8975_CHANNEL(axis, index) \
438 { \
439 .type = IIO_MAGN, \
440 .modified = 1, \
441 .channel2 = IIO_MOD_##axis, \
Jonathan Cameron3a0b4422013-02-27 19:40:48 +0000442 .info_mask_separate = BIT(IIO_CHAN_INFO_RAW) | \
443 BIT(IIO_CHAN_INFO_SCALE), \
Jonathan Cameron694e1b52011-08-12 17:48:03 +0100444 .address = index, \
445 }
446
447static const struct iio_chan_spec ak8975_channels[] = {
448 AK8975_CHANNEL(X, 0), AK8975_CHANNEL(Y, 1), AK8975_CHANNEL(Z, 2),
449};
450
Jonathan Cameron6fe81352011-05-18 14:42:37 +0100451static const struct iio_info ak8975_info = {
Jonathan Cameron694e1b52011-08-12 17:48:03 +0100452 .read_raw = &ak8975_read_raw,
Jonathan Cameron6fe81352011-05-18 14:42:37 +0100453 .driver_module = THIS_MODULE,
454};
455
Bill Pemberton4ae1c612012-11-19 13:21:57 -0500456static int ak8975_probe(struct i2c_client *client,
Andrew Chew3285aae2010-09-08 22:02:17 -0700457 const struct i2c_device_id *id)
458{
459 struct ak8975_data *data;
Jonathan Cameron338473c2011-06-27 13:07:54 +0100460 struct iio_dev *indio_dev;
461 int eoc_gpio;
Andrew Chew3285aae2010-09-08 22:02:17 -0700462 int err;
463
Andrew Chew3285aae2010-09-08 22:02:17 -0700464 /* Grab and set up the supplied GPIO. */
Jacek Anaszewskif4b7f752013-05-07 11:41:00 +0100465 if (client->dev.platform_data)
Jonathan Cameronf6d838d2011-09-21 11:15:59 +0100466 eoc_gpio = *(int *)(client->dev.platform_data);
Jacek Anaszewskif4b7f752013-05-07 11:41:00 +0100467 else if (client->dev.of_node)
468 eoc_gpio = of_get_gpio(client->dev.of_node, 0);
469 else
470 eoc_gpio = -1;
471
472 if (eoc_gpio == -EPROBE_DEFER)
473 return -EPROBE_DEFER;
Andrew Chew3285aae2010-09-08 22:02:17 -0700474
Alan Cox01fbb472011-04-06 13:31:40 +0100475 /* We may not have a GPIO based IRQ to scan, that is fine, we will
476 poll if so */
Stephen Warren7c6c9362011-09-21 11:16:00 +0100477 if (gpio_is_valid(eoc_gpio)) {
Leed Aguilar82f2acd2012-06-06 16:15:40 -0400478 err = gpio_request_one(eoc_gpio, GPIOF_IN, "ak_8975");
Alan Cox01fbb472011-04-06 13:31:40 +0100479 if (err < 0) {
480 dev_err(&client->dev,
481 "failed to request GPIO %d, error %d\n",
Jonathan Cameron338473c2011-06-27 13:07:54 +0100482 eoc_gpio, err);
483 goto exit;
Alan Cox01fbb472011-04-06 13:31:40 +0100484 }
Stephen Warren7c6c9362011-09-21 11:16:00 +0100485 }
Andrew Chew3285aae2010-09-08 22:02:17 -0700486
Jonathan Cameron338473c2011-06-27 13:07:54 +0100487 /* Register with IIO */
Lars-Peter Clausen7cbb7532012-04-26 13:35:01 +0200488 indio_dev = iio_device_alloc(sizeof(*data));
Jonathan Cameron338473c2011-06-27 13:07:54 +0100489 if (indio_dev == NULL) {
490 err = -ENOMEM;
491 goto exit_gpio;
492 }
493 data = iio_priv(indio_dev);
Preetham Chandru40f32d92012-04-09 18:05:01 +0530494 i2c_set_clientdata(client, indio_dev);
Jacek Anaszewski94a6d5c2013-05-07 11:41:00 +0100495
496 data->client = client;
497 data->eoc_gpio = eoc_gpio;
498 data->eoc_irq = 0;
499
Andrew Chew3285aae2010-09-08 22:02:17 -0700500 /* Perform some basic start-of-day setup of the device. */
501 err = ak8975_setup(client);
502 if (err < 0) {
503 dev_err(&client->dev, "AK8975 initialization fails\n");
Stephen Warrenad31d252011-09-21 11:16:01 +0100504 goto exit_free_iio;
Andrew Chew3285aae2010-09-08 22:02:17 -0700505 }
506
Jonathan Cameron338473c2011-06-27 13:07:54 +0100507 data->client = client;
508 mutex_init(&data->lock);
Jonathan Cameron338473c2011-06-27 13:07:54 +0100509 data->eoc_gpio = eoc_gpio;
510 indio_dev->dev.parent = &client->dev;
Jonathan Cameron694e1b52011-08-12 17:48:03 +0100511 indio_dev->channels = ak8975_channels;
512 indio_dev->num_channels = ARRAY_SIZE(ak8975_channels);
Jonathan Cameron338473c2011-06-27 13:07:54 +0100513 indio_dev->info = &ak8975_info;
514 indio_dev->modes = INDIO_DIRECT_MODE;
Andrew Chew3285aae2010-09-08 22:02:17 -0700515
Jonathan Cameron338473c2011-06-27 13:07:54 +0100516 err = iio_device_register(indio_dev);
Andrew Chew3285aae2010-09-08 22:02:17 -0700517 if (err < 0)
518 goto exit_free_iio;
519
520 return 0;
521
522exit_free_iio:
Lars-Peter Clausen7cbb7532012-04-26 13:35:01 +0200523 iio_device_free(indio_dev);
Jacek Anaszewski94a6d5c2013-05-07 11:41:00 +0100524 if (data->eoc_irq)
525 free_irq(data->eoc_irq, data);
Andrew Chew3285aae2010-09-08 22:02:17 -0700526exit_gpio:
Stephen Warren7c6c9362011-09-21 11:16:00 +0100527 if (gpio_is_valid(eoc_gpio))
Jonathan Cameron338473c2011-06-27 13:07:54 +0100528 gpio_free(eoc_gpio);
Andrew Chew3285aae2010-09-08 22:02:17 -0700529exit:
530 return err;
531}
532
Bill Pemberton447d4f22012-11-19 13:26:37 -0500533static int ak8975_remove(struct i2c_client *client)
Andrew Chew3285aae2010-09-08 22:02:17 -0700534{
Jonathan Cameron338473c2011-06-27 13:07:54 +0100535 struct iio_dev *indio_dev = i2c_get_clientdata(client);
536 struct ak8975_data *data = iio_priv(indio_dev);
Andrew Chew3285aae2010-09-08 22:02:17 -0700537
Jonathan Cameron338473c2011-06-27 13:07:54 +0100538 iio_device_unregister(indio_dev);
Andrew Chew3285aae2010-09-08 22:02:17 -0700539
Jacek Anaszewski94a6d5c2013-05-07 11:41:00 +0100540 if (data->eoc_irq)
541 free_irq(data->eoc_irq, data);
542
Jonathan Camerond2fffd62011-10-14 14:46:58 +0100543 if (gpio_is_valid(data->eoc_gpio))
544 gpio_free(data->eoc_gpio);
545
Lars-Peter Clausen7cbb7532012-04-26 13:35:01 +0200546 iio_device_free(indio_dev);
Andrew Chew3285aae2010-09-08 22:02:17 -0700547
548 return 0;
549}
550
551static const struct i2c_device_id ak8975_id[] = {
552 {"ak8975", 0},
553 {}
554};
555
556MODULE_DEVICE_TABLE(i2c, ak8975_id);
557
Olof Johansson54461c32011-12-22 18:46:42 -0800558static const struct of_device_id ak8975_of_match[] = {
559 { .compatible = "asahi-kasei,ak8975", },
560 { .compatible = "ak8975", },
561 { }
562};
563MODULE_DEVICE_TABLE(of, ak8975_of_match);
564
Andrew Chew3285aae2010-09-08 22:02:17 -0700565static struct i2c_driver ak8975_driver = {
566 .driver = {
567 .name = "ak8975",
Olof Johansson54461c32011-12-22 18:46:42 -0800568 .of_match_table = ak8975_of_match,
Andrew Chew3285aae2010-09-08 22:02:17 -0700569 },
570 .probe = ak8975_probe,
Bill Pembertone543acf2012-11-19 13:21:38 -0500571 .remove = ak8975_remove,
Andrew Chew3285aae2010-09-08 22:02:17 -0700572 .id_table = ak8975_id,
573};
Lars-Peter Clausen6e5af182011-11-16 10:13:38 +0100574module_i2c_driver(ak8975_driver);
Andrew Chew3285aae2010-09-08 22:02:17 -0700575
576MODULE_AUTHOR("Laxman Dewangan <ldewangan@nvidia.com>");
577MODULE_DESCRIPTION("AK8975 magnetometer driver");
578MODULE_LICENSE("GPL");