2 * Sensortek STK8BA50 3-Axis Accelerometer
4 * Copyright (c) 2015, Intel Corporation.
6 * This file is subject to the terms and conditions of version 2 of
7 * the GNU General Public License. See the file COPYING in the main
8 * directory of this archive for more details.
10 * STK8BA50 7-bit I2C address: 0x18.
13 #include <linux/acpi.h>
14 #include <linux/gpio/consumer.h>
15 #include <linux/i2c.h>
16 #include <linux/interrupt.h>
17 #include <linux/kernel.h>
18 #include <linux/module.h>
19 #include <linux/iio/buffer.h>
20 #include <linux/iio/iio.h>
21 #include <linux/iio/sysfs.h>
22 #include <linux/iio/trigger.h>
23 #include <linux/iio/triggered_buffer.h>
24 #include <linux/iio/trigger_consumer.h>
26 #define STK8BA50_REG_XOUT 0x02
27 #define STK8BA50_REG_YOUT 0x04
28 #define STK8BA50_REG_ZOUT 0x06
29 #define STK8BA50_REG_RANGE 0x0F
30 #define STK8BA50_REG_BWSEL 0x10
31 #define STK8BA50_REG_POWMODE 0x11
32 #define STK8BA50_REG_SWRST 0x14
33 #define STK8BA50_REG_INTEN2 0x17
34 #define STK8BA50_REG_INTMAP2 0x1A
36 #define STK8BA50_MODE_NORMAL 0
37 #define STK8BA50_MODE_SUSPEND 1
38 #define STK8BA50_MODE_POWERBIT BIT(7)
39 #define STK8BA50_DATA_SHIFT 6
40 #define STK8BA50_RESET_CMD 0xB6
41 #define STK8BA50_SR_1792HZ_IDX 7
42 #define STK8BA50_DREADY_INT_MASK 0x10
43 #define STK8BA50_DREADY_INT_MAP 0x81
44 #define STK8BA50_ALL_CHANNEL_MASK 7
45 #define STK8BA50_ALL_CHANNEL_SIZE 6
47 #define STK8BA50_DRIVER_NAME "stk8ba50"
48 #define STK8BA50_GPIO "stk8ba50_gpio"
49 #define STK8BA50_IRQ_NAME "stk8ba50_event"
51 #define STK8BA50_SCALE_AVAIL "0.0384 0.0767 0.1534 0.3069"
54 * The accelerometer has four measurement ranges:
55 * +/-2g; +/-4g; +/-8g; +/-16g
57 * Acceleration values are 10-bit, 2's complement.
58 * Scales are calculated as following:
60 * scale1 = (2 + 2) * 9.81 / (2^10 - 1) = 0.0384
61 * scale2 = (4 + 4) * 9.81 / (2^10 - 1) = 0.0767
64 * Scales are stored in this format:
65 * { <register value>, <scale value> }
67 * Locally, the range is stored as a table index.
72 } stk8ba50_scale_table
[] = {
73 {3, 38400}, {5, 76700}, {8, 153400}, {12, 306900}
76 /* Sample rates are stored as { <register value>, <Hz value> } */
80 } stk8ba50_samp_freq_table
[] = {
81 {0x08, 14}, {0x09, 25}, {0x0A, 56}, {0x0B, 112},
82 {0x0C, 224}, {0x0D, 448}, {0x0E, 896}, {0x0F, 1792}
85 /* Used to map scan mask bits to their corresponding channel register. */
86 static const int stk8ba50_channel_table
[] = {
92 struct stk8ba50_data
{
93 struct i2c_client
*client
;
97 struct iio_trigger
*dready_trig
;
98 bool dready_trigger_on
;
100 * 3 x 16-bit channels (10-bit data, 6-bit padding) +
102 * 4 x 16 64-bit timestamp
107 #define STK8BA50_ACCEL_CHANNEL(index, reg, axis) { \
111 .channel2 = IIO_MOD_##axis, \
112 .info_mask_separate = BIT(IIO_CHAN_INFO_RAW), \
113 .info_mask_shared_by_type = BIT(IIO_CHAN_INFO_SCALE), \
114 BIT(IIO_CHAN_INFO_SAMP_FREQ), \
115 .scan_index = index, \
120 .shift = STK8BA50_DATA_SHIFT, \
121 .endianness = IIO_CPU, \
125 static const struct iio_chan_spec stk8ba50_channels
[] = {
126 STK8BA50_ACCEL_CHANNEL(0, STK8BA50_REG_XOUT
, X
),
127 STK8BA50_ACCEL_CHANNEL(1, STK8BA50_REG_YOUT
, Y
),
128 STK8BA50_ACCEL_CHANNEL(2, STK8BA50_REG_ZOUT
, Z
),
129 IIO_CHAN_SOFT_TIMESTAMP(3),
132 static IIO_CONST_ATTR(in_accel_scale_available
, STK8BA50_SCALE_AVAIL
);
134 static IIO_CONST_ATTR_SAMP_FREQ_AVAIL("14 25 56 112 224 448 896 1792");
136 static struct attribute
*stk8ba50_attributes
[] = {
137 &iio_const_attr_in_accel_scale_available
.dev_attr
.attr
,
138 &iio_const_attr_sampling_frequency_available
.dev_attr
.attr
,
142 static const struct attribute_group stk8ba50_attribute_group
= {
143 .attrs
= stk8ba50_attributes
146 static int stk8ba50_read_accel(struct stk8ba50_data
*data
, u8 reg
)
149 struct i2c_client
*client
= data
->client
;
151 ret
= i2c_smbus_read_word_data(client
, reg
);
153 dev_err(&client
->dev
, "register read failed\n");
160 static int stk8ba50_data_rdy_trigger_set_state(struct iio_trigger
*trig
,
163 struct iio_dev
*indio_dev
= iio_trigger_get_drvdata(trig
);
164 struct stk8ba50_data
*data
= iio_priv(indio_dev
);
168 ret
= i2c_smbus_write_byte_data(data
->client
,
169 STK8BA50_REG_INTEN2
, STK8BA50_DREADY_INT_MASK
);
171 ret
= i2c_smbus_write_byte_data(data
->client
,
172 STK8BA50_REG_INTEN2
, 0x00);
175 dev_err(&data
->client
->dev
, "failed to set trigger state\n");
177 data
->dready_trigger_on
= state
;
182 static const struct iio_trigger_ops stk8ba50_trigger_ops
= {
183 .set_trigger_state
= stk8ba50_data_rdy_trigger_set_state
,
184 .owner
= THIS_MODULE
,
187 static int stk8ba50_set_power(struct stk8ba50_data
*data
, bool mode
)
191 struct i2c_client
*client
= data
->client
;
193 ret
= i2c_smbus_read_byte_data(client
, STK8BA50_REG_POWMODE
);
198 masked_reg
= ret
| STK8BA50_MODE_POWERBIT
;
200 masked_reg
= ret
& (~STK8BA50_MODE_POWERBIT
);
202 ret
= i2c_smbus_write_byte_data(client
, STK8BA50_REG_POWMODE
,
210 dev_err(&client
->dev
, "failed to change sensor mode\n");
214 static int stk8ba50_read_raw(struct iio_dev
*indio_dev
,
215 struct iio_chan_spec
const *chan
,
216 int *val
, int *val2
, long mask
)
218 struct stk8ba50_data
*data
= iio_priv(indio_dev
);
222 case IIO_CHAN_INFO_RAW
:
223 if (iio_buffer_enabled(indio_dev
))
225 mutex_lock(&data
->lock
);
226 ret
= stk8ba50_set_power(data
, STK8BA50_MODE_NORMAL
);
228 mutex_unlock(&data
->lock
);
231 ret
= stk8ba50_read_accel(data
, chan
->address
);
233 stk8ba50_set_power(data
, STK8BA50_MODE_SUSPEND
);
234 mutex_unlock(&data
->lock
);
237 *val
= sign_extend32(ret
>> STK8BA50_DATA_SHIFT
, 9);
238 stk8ba50_set_power(data
, STK8BA50_MODE_SUSPEND
);
239 mutex_unlock(&data
->lock
);
241 case IIO_CHAN_INFO_SCALE
:
243 *val2
= stk8ba50_scale_table
[data
->range
].scale_val
;
244 return IIO_VAL_INT_PLUS_MICRO
;
245 case IIO_CHAN_INFO_SAMP_FREQ
:
246 *val
= stk8ba50_samp_freq_table
247 [data
->sample_rate_idx
].samp_freq
;
255 static int stk8ba50_write_raw(struct iio_dev
*indio_dev
,
256 struct iio_chan_spec
const *chan
,
257 int val
, int val2
, long mask
)
262 struct stk8ba50_data
*data
= iio_priv(indio_dev
);
265 case IIO_CHAN_INFO_SCALE
:
269 for (i
= 0; i
< ARRAY_SIZE(stk8ba50_scale_table
); i
++)
270 if (val2
== stk8ba50_scale_table
[i
].scale_val
) {
277 ret
= i2c_smbus_write_byte_data(data
->client
,
279 stk8ba50_scale_table
[index
].reg_val
);
281 dev_err(&data
->client
->dev
,
282 "failed to set measurement range\n");
287 case IIO_CHAN_INFO_SAMP_FREQ
:
288 for (i
= 0; i
< ARRAY_SIZE(stk8ba50_samp_freq_table
); i
++)
289 if (val
== stk8ba50_samp_freq_table
[i
].samp_freq
) {
296 ret
= i2c_smbus_write_byte_data(data
->client
,
298 stk8ba50_samp_freq_table
[index
].reg_val
);
300 dev_err(&data
->client
->dev
,
301 "failed to set sampling rate\n");
303 data
->sample_rate_idx
= index
;
311 static const struct iio_info stk8ba50_info
= {
312 .driver_module
= THIS_MODULE
,
313 .read_raw
= stk8ba50_read_raw
,
314 .write_raw
= stk8ba50_write_raw
,
315 .attrs
= &stk8ba50_attribute_group
,
318 static irqreturn_t
stk8ba50_trigger_handler(int irq
, void *p
)
320 struct iio_poll_func
*pf
= p
;
321 struct iio_dev
*indio_dev
= pf
->indio_dev
;
322 struct stk8ba50_data
*data
= iio_priv(indio_dev
);
325 mutex_lock(&data
->lock
);
327 * Do a bulk read if all channels are requested,
328 * from 0x02 (XOUT1) to 0x07 (ZOUT2)
330 if (*(indio_dev
->active_scan_mask
) == STK8BA50_ALL_CHANNEL_MASK
) {
331 ret
= i2c_smbus_read_i2c_block_data(data
->client
,
333 STK8BA50_ALL_CHANNEL_SIZE
,
335 if (ret
< STK8BA50_ALL_CHANNEL_SIZE
) {
336 dev_err(&data
->client
->dev
, "register read failed\n");
340 for_each_set_bit(bit
, indio_dev
->active_scan_mask
,
341 indio_dev
->masklength
) {
342 ret
= stk8ba50_read_accel(data
,
343 stk8ba50_channel_table
[bit
]);
347 data
->buffer
[i
++] = ret
;
350 iio_push_to_buffers_with_timestamp(indio_dev
, data
->buffer
,
353 mutex_unlock(&data
->lock
);
354 iio_trigger_notify_done(indio_dev
->trig
);
359 static irqreturn_t
stk8ba50_data_rdy_trig_poll(int irq
, void *private)
361 struct iio_dev
*indio_dev
= private;
362 struct stk8ba50_data
*data
= iio_priv(indio_dev
);
364 if (data
->dready_trigger_on
)
365 iio_trigger_poll(data
->dready_trig
);
370 static int stk8ba50_buffer_preenable(struct iio_dev
*indio_dev
)
372 struct stk8ba50_data
*data
= iio_priv(indio_dev
);
374 return stk8ba50_set_power(data
, STK8BA50_MODE_NORMAL
);
377 static int stk8ba50_buffer_postdisable(struct iio_dev
*indio_dev
)
379 struct stk8ba50_data
*data
= iio_priv(indio_dev
);
381 return stk8ba50_set_power(data
, STK8BA50_MODE_SUSPEND
);
384 static const struct iio_buffer_setup_ops stk8ba50_buffer_setup_ops
= {
385 .preenable
= stk8ba50_buffer_preenable
,
386 .postenable
= iio_triggered_buffer_postenable
,
387 .predisable
= iio_triggered_buffer_predisable
,
388 .postdisable
= stk8ba50_buffer_postdisable
,
391 static int stk8ba50_gpio_probe(struct i2c_client
*client
)
394 struct gpio_desc
*gpio
;
402 /* data ready gpio interrupt pin */
403 gpio
= devm_gpiod_get_index(dev
, STK8BA50_GPIO
, 0, GPIOD_IN
);
405 dev_err(dev
, "acpi gpio get index failed\n");
406 return PTR_ERR(gpio
);
409 ret
= gpiod_to_irq(gpio
);
410 dev_dbg(dev
, "GPIO resource, no:%d irq:%d\n", desc_to_gpio(gpio
), ret
);
415 static int stk8ba50_probe(struct i2c_client
*client
,
416 const struct i2c_device_id
*id
)
419 struct iio_dev
*indio_dev
;
420 struct stk8ba50_data
*data
;
422 indio_dev
= devm_iio_device_alloc(&client
->dev
, sizeof(*data
));
424 dev_err(&client
->dev
, "iio allocation failed!\n");
428 data
= iio_priv(indio_dev
);
429 data
->client
= client
;
430 i2c_set_clientdata(client
, indio_dev
);
431 mutex_init(&data
->lock
);
433 indio_dev
->dev
.parent
= &client
->dev
;
434 indio_dev
->info
= &stk8ba50_info
;
435 indio_dev
->name
= STK8BA50_DRIVER_NAME
;
436 indio_dev
->modes
= INDIO_DIRECT_MODE
;
437 indio_dev
->channels
= stk8ba50_channels
;
438 indio_dev
->num_channels
= ARRAY_SIZE(stk8ba50_channels
);
440 /* Reset all registers on startup */
441 ret
= i2c_smbus_write_byte_data(client
,
442 STK8BA50_REG_SWRST
, STK8BA50_RESET_CMD
);
444 dev_err(&client
->dev
, "failed to reset sensor\n");
448 /* The default range is +/-2g */
451 /* The default sampling rate is 1792 Hz (maximum) */
452 data
->sample_rate_idx
= STK8BA50_SR_1792HZ_IDX
;
454 /* Set up interrupts */
455 ret
= i2c_smbus_write_byte_data(client
,
456 STK8BA50_REG_INTEN2
, STK8BA50_DREADY_INT_MASK
);
458 dev_err(&client
->dev
, "failed to set up interrupts\n");
461 ret
= i2c_smbus_write_byte_data(client
,
462 STK8BA50_REG_INTMAP2
, STK8BA50_DREADY_INT_MAP
);
464 dev_err(&client
->dev
, "failed to set up interrupts\n");
469 client
->irq
= stk8ba50_gpio_probe(client
);
471 if (client
->irq
>= 0) {
472 ret
= devm_request_threaded_irq(&client
->dev
, client
->irq
,
473 stk8ba50_data_rdy_trig_poll
,
475 IRQF_TRIGGER_RISING
|
480 dev_err(&client
->dev
, "request irq %d failed\n",
485 data
->dready_trig
= devm_iio_trigger_alloc(&client
->dev
,
489 if (!data
->dready_trig
) {
494 data
->dready_trig
->dev
.parent
= &client
->dev
;
495 data
->dready_trig
->ops
= &stk8ba50_trigger_ops
;
496 iio_trigger_set_drvdata(data
->dready_trig
, indio_dev
);
497 ret
= iio_trigger_register(data
->dready_trig
);
499 dev_err(&client
->dev
, "iio trigger register failed\n");
504 ret
= iio_triggered_buffer_setup(indio_dev
,
505 iio_pollfunc_store_time
,
506 stk8ba50_trigger_handler
,
507 &stk8ba50_buffer_setup_ops
);
509 dev_err(&client
->dev
, "iio triggered buffer setup failed\n");
510 goto err_trigger_unregister
;
513 ret
= iio_device_register(indio_dev
);
515 dev_err(&client
->dev
, "device_register failed\n");
516 goto err_buffer_cleanup
;
522 iio_triggered_buffer_cleanup(indio_dev
);
523 err_trigger_unregister
:
524 if (data
->dready_trig
)
525 iio_trigger_unregister(data
->dready_trig
);
527 stk8ba50_set_power(data
, STK8BA50_MODE_SUSPEND
);
531 static int stk8ba50_remove(struct i2c_client
*client
)
533 struct iio_dev
*indio_dev
= i2c_get_clientdata(client
);
534 struct stk8ba50_data
*data
= iio_priv(indio_dev
);
536 iio_device_unregister(indio_dev
);
537 iio_triggered_buffer_cleanup(indio_dev
);
539 if (data
->dready_trig
)
540 iio_trigger_unregister(data
->dready_trig
);
542 return stk8ba50_set_power(data
, STK8BA50_MODE_SUSPEND
);
545 #ifdef CONFIG_PM_SLEEP
546 static int stk8ba50_suspend(struct device
*dev
)
548 struct stk8ba50_data
*data
;
550 data
= iio_priv(i2c_get_clientdata(to_i2c_client(dev
)));
552 return stk8ba50_set_power(data
, STK8BA50_MODE_SUSPEND
);
555 static int stk8ba50_resume(struct device
*dev
)
557 struct stk8ba50_data
*data
;
559 data
= iio_priv(i2c_get_clientdata(to_i2c_client(dev
)));
561 return stk8ba50_set_power(data
, STK8BA50_MODE_NORMAL
);
564 static SIMPLE_DEV_PM_OPS(stk8ba50_pm_ops
, stk8ba50_suspend
, stk8ba50_resume
);
566 #define STK8BA50_PM_OPS (&stk8ba50_pm_ops)
568 #define STK8BA50_PM_OPS NULL
571 static const struct i2c_device_id stk8ba50_i2c_id
[] = {
575 MODULE_DEVICE_TABLE(i2c
, stk8ba50_i2c_id
);
577 static const struct acpi_device_id stk8ba50_acpi_id
[] = {
582 MODULE_DEVICE_TABLE(acpi
, stk8ba50_acpi_id
);
584 static struct i2c_driver stk8ba50_driver
= {
587 .pm
= STK8BA50_PM_OPS
,
588 .acpi_match_table
= ACPI_PTR(stk8ba50_acpi_id
),
590 .probe
= stk8ba50_probe
,
591 .remove
= stk8ba50_remove
,
592 .id_table
= stk8ba50_i2c_id
,
595 module_i2c_driver(stk8ba50_driver
);
597 MODULE_AUTHOR("Tiberiu Breana <tiberiu.a.breana@intel.com>");
598 MODULE_DESCRIPTION("STK8BA50 3-Axis Accelerometer driver");
599 MODULE_LICENSE("GPL v2");