2 * itg3200_core.c -- support InvenSense ITG3200
3 * Digital 3-Axis Gyroscope driver
5 * Copyright (c) 2011 Christian Strobel <christian.strobel@iis.fraunhofer.de>
6 * Copyright (c) 2011 Manuel Stahl <manuel.stahl@iis.fraunhofer.de>
7 * Copyright (c) 2012 Thorsten Nowak <thorsten.nowak@iis.fraunhofer.de>
9 * This program is free software; you can redistribute it and/or modify
10 * it under the terms of the GNU General Public License version 2 as
11 * published by the Free Software Foundation.
14 * - Support digital low pass filter
15 * - Support power management
18 #include <linux/interrupt.h>
19 #include <linux/irq.h>
20 #include <linux/i2c.h>
21 #include <linux/gpio.h>
22 #include <linux/slab.h>
23 #include <linux/stat.h>
24 #include <linux/module.h>
25 #include <linux/delay.h>
27 #include <linux/iio/iio.h>
28 #include <linux/iio/sysfs.h>
29 #include <linux/iio/events.h>
30 #include <linux/iio/buffer.h>
32 #include <linux/iio/gyro/itg3200.h>
35 int itg3200_write_reg_8(struct iio_dev
*indio_dev
,
36 u8 reg_address
, u8 val
)
38 struct itg3200
*st
= iio_priv(indio_dev
);
40 return i2c_smbus_write_byte_data(st
->i2c
, 0x80 | reg_address
, val
);
43 int itg3200_read_reg_8(struct iio_dev
*indio_dev
,
44 u8 reg_address
, u8
*val
)
46 struct itg3200
*st
= iio_priv(indio_dev
);
49 ret
= i2c_smbus_read_byte_data(st
->i2c
, reg_address
);
56 static int itg3200_read_reg_s16(struct iio_dev
*indio_dev
, u8 lower_reg_address
,
59 struct itg3200
*st
= iio_priv(indio_dev
);
60 struct i2c_client
*client
= st
->i2c
;
64 struct i2c_msg msg
[2] = {
67 .flags
= client
->flags
,
69 .buf
= (char *)&lower_reg_address
,
73 .flags
= client
->flags
| I2C_M_RD
,
79 lower_reg_address
|= 0x80;
80 ret
= i2c_transfer(client
->adapter
, msg
, 2);
84 return (ret
== 2) ? 0 : ret
;
87 static int itg3200_read_raw(struct iio_dev
*indio_dev
,
88 const struct iio_chan_spec
*chan
,
89 int *val
, int *val2
, long info
)
95 case IIO_CHAN_INFO_RAW
:
96 reg
= (u8
)chan
->address
;
97 ret
= itg3200_read_reg_s16(indio_dev
, reg
, val
);
99 case IIO_CHAN_INFO_SCALE
:
101 if (chan
->type
== IIO_TEMP
)
102 *val2
= 1000000000/280;
104 *val2
= 1214142; /* (1 / 14,375) * (PI / 180) */
105 return IIO_VAL_INT_PLUS_NANO
;
106 case IIO_CHAN_INFO_OFFSET
:
107 /* Only the temperature channel has an offset */
117 static ssize_t
itg3200_read_frequency(struct device
*dev
,
118 struct device_attribute
*attr
, char *buf
)
120 struct iio_dev
*indio_dev
= dev_to_iio_dev(dev
);
124 ret
= itg3200_read_reg_8(indio_dev
, ITG3200_REG_DLPF
, &val
);
128 sps
= (val
& ITG3200_DLPF_CFG_MASK
) ? 1000 : 8000;
130 ret
= itg3200_read_reg_8(indio_dev
, ITG3200_REG_SAMPLE_RATE_DIV
, &val
);
136 return sprintf(buf
, "%d\n", sps
);
139 static ssize_t
itg3200_write_frequency(struct device
*dev
,
140 struct device_attribute
*attr
,
144 struct iio_dev
*indio_dev
= dev_to_iio_dev(dev
);
149 ret
= kstrtouint(buf
, 10, &val
);
153 mutex_lock(&indio_dev
->mlock
);
155 ret
= itg3200_read_reg_8(indio_dev
, ITG3200_REG_DLPF
, &t
);
163 t
= ((t
& ITG3200_DLPF_CFG_MASK
) ? 1000u : 8000u) / val
- 1;
165 ret
= itg3200_write_reg_8(indio_dev
, ITG3200_REG_SAMPLE_RATE_DIV
, t
);
168 mutex_unlock(&indio_dev
->mlock
);
170 return ret
? ret
: len
;
174 * Reset device and internal registers to the power-up-default settings
175 * Use the gyro clock as reference, as suggested by the datasheet
177 static int itg3200_reset(struct iio_dev
*indio_dev
)
179 struct itg3200
*st
= iio_priv(indio_dev
);
182 dev_dbg(&st
->i2c
->dev
, "reset device");
184 ret
= itg3200_write_reg_8(indio_dev
,
185 ITG3200_REG_POWER_MANAGEMENT
,
188 dev_err(&st
->i2c
->dev
, "error resetting device");
192 /* Wait for PLL (1ms according to datasheet) */
195 ret
= itg3200_write_reg_8(indio_dev
,
196 ITG3200_REG_IRQ_CONFIG
,
197 ITG3200_IRQ_ACTIVE_HIGH
|
198 ITG3200_IRQ_PUSH_PULL
|
199 ITG3200_IRQ_LATCH_50US_PULSE
|
200 ITG3200_IRQ_LATCH_CLEAR_ANY
);
203 dev_err(&st
->i2c
->dev
, "error init device");
209 /* itg3200_enable_full_scale() - Disables the digital low pass filter */
210 static int itg3200_enable_full_scale(struct iio_dev
*indio_dev
)
215 ret
= itg3200_read_reg_8(indio_dev
, ITG3200_REG_DLPF
, &val
);
219 val
|= ITG3200_DLPF_FS_SEL_2000
;
220 return itg3200_write_reg_8(indio_dev
, ITG3200_REG_DLPF
, val
);
226 static int itg3200_initial_setup(struct iio_dev
*indio_dev
)
228 struct itg3200
*st
= iio_priv(indio_dev
);
232 ret
= itg3200_read_reg_8(indio_dev
, ITG3200_REG_ADDRESS
, &val
);
236 if (((val
>> 1) & 0x3f) != 0x34) {
237 dev_err(&st
->i2c
->dev
, "invalid reg value 0x%02x", val
);
242 ret
= itg3200_reset(indio_dev
);
246 ret
= itg3200_enable_full_scale(indio_dev
);
252 { .sign = 's', .realbits = 16, .storagebits = 16, .endianness = IIO_BE }
254 #define ITG3200_GYRO_CHAN(_mod) { \
255 .type = IIO_ANGL_VEL, \
257 .channel2 = IIO_MOD_ ## _mod, \
258 .info_mask_separate = BIT(IIO_CHAN_INFO_RAW), \
259 .info_mask_shared_by_type = BIT(IIO_CHAN_INFO_SCALE), \
260 .address = ITG3200_REG_GYRO_ ## _mod ## OUT_H, \
261 .scan_index = ITG3200_SCAN_GYRO_ ## _mod, \
262 .scan_type = ITG3200_ST, \
265 static const struct iio_chan_spec itg3200_channels
[] = {
268 .channel2
= IIO_NO_MOD
,
269 .info_mask_separate
= BIT(IIO_CHAN_INFO_RAW
),
270 .info_mask_shared_by_type
= BIT(IIO_CHAN_INFO_OFFSET
) |
271 BIT(IIO_CHAN_INFO_SCALE
),
272 .address
= ITG3200_REG_TEMP_OUT_H
,
273 .scan_index
= ITG3200_SCAN_TEMP
,
274 .scan_type
= ITG3200_ST
,
276 ITG3200_GYRO_CHAN(X
),
277 ITG3200_GYRO_CHAN(Y
),
278 ITG3200_GYRO_CHAN(Z
),
279 IIO_CHAN_SOFT_TIMESTAMP(ITG3200_SCAN_ELEMENTS
),
282 /* IIO device attributes */
283 static IIO_DEV_ATTR_SAMP_FREQ(S_IWUSR
| S_IRUGO
, itg3200_read_frequency
,
284 itg3200_write_frequency
);
286 static struct attribute
*itg3200_attributes
[] = {
287 &iio_dev_attr_sampling_frequency
.dev_attr
.attr
,
291 static const struct attribute_group itg3200_attribute_group
= {
292 .attrs
= itg3200_attributes
,
295 static const struct iio_info itg3200_info
= {
296 .attrs
= &itg3200_attribute_group
,
297 .read_raw
= &itg3200_read_raw
,
298 .driver_module
= THIS_MODULE
,
301 static const unsigned long itg3200_available_scan_masks
[] = { 0xffffffff, 0x0 };
303 static int itg3200_probe(struct i2c_client
*client
,
304 const struct i2c_device_id
*id
)
308 struct iio_dev
*indio_dev
;
310 dev_dbg(&client
->dev
, "probe I2C dev with IRQ %i", client
->irq
);
312 indio_dev
= iio_device_alloc(sizeof(*st
));
313 if (indio_dev
== NULL
) {
318 st
= iio_priv(indio_dev
);
320 i2c_set_clientdata(client
, indio_dev
);
323 indio_dev
->dev
.parent
= &client
->dev
;
324 indio_dev
->name
= client
->dev
.driver
->name
;
325 indio_dev
->channels
= itg3200_channels
;
326 indio_dev
->num_channels
= ARRAY_SIZE(itg3200_channels
);
327 indio_dev
->available_scan_masks
= itg3200_available_scan_masks
;
328 indio_dev
->info
= &itg3200_info
;
329 indio_dev
->modes
= INDIO_DIRECT_MODE
;
331 ret
= itg3200_buffer_configure(indio_dev
);
336 ret
= itg3200_probe_trigger(indio_dev
);
338 goto error_unconfigure_buffer
;
341 ret
= itg3200_initial_setup(indio_dev
);
343 goto error_remove_trigger
;
345 ret
= iio_device_register(indio_dev
);
347 goto error_remove_trigger
;
351 error_remove_trigger
:
353 itg3200_remove_trigger(indio_dev
);
354 error_unconfigure_buffer
:
355 itg3200_buffer_unconfigure(indio_dev
);
357 iio_device_free(indio_dev
);
362 static int itg3200_remove(struct i2c_client
*client
)
364 struct iio_dev
*indio_dev
= i2c_get_clientdata(client
);
366 iio_device_unregister(indio_dev
);
369 itg3200_remove_trigger(indio_dev
);
371 itg3200_buffer_unconfigure(indio_dev
);
373 iio_device_free(indio_dev
);
378 static const struct i2c_device_id itg3200_id
[] = {
382 MODULE_DEVICE_TABLE(i2c
, itg3200_id
);
384 static struct i2c_driver itg3200_driver
= {
386 .owner
= THIS_MODULE
,
389 .id_table
= itg3200_id
,
390 .probe
= itg3200_probe
,
391 .remove
= itg3200_remove
,
394 module_i2c_driver(itg3200_driver
);
396 MODULE_AUTHOR("Christian Strobel <christian.strobel@iis.fraunhofer.de>");
397 MODULE_DESCRIPTION("ITG3200 Gyroscope I2C driver");
398 MODULE_LICENSE("GPL v2");