556 lines
14 KiB
C
556 lines
14 KiB
C
// SPDX-License-Identifier: GPL-2.0-only
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/*
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* Sensortek STK8BA50 3-Axis Accelerometer
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*
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* Copyright (c) 2015, Intel Corporation.
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*
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* STK8BA50 7-bit I2C address: 0x18.
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*/
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#include <linux/acpi.h>
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#include <linux/i2c.h>
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#include <linux/interrupt.h>
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#include <linux/kernel.h>
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#include <linux/module.h>
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#include <linux/iio/buffer.h>
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#include <linux/iio/iio.h>
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#include <linux/iio/sysfs.h>
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#include <linux/iio/trigger.h>
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#include <linux/iio/triggered_buffer.h>
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#include <linux/iio/trigger_consumer.h>
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#define STK8BA50_REG_XOUT 0x02
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#define STK8BA50_REG_YOUT 0x04
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#define STK8BA50_REG_ZOUT 0x06
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#define STK8BA50_REG_RANGE 0x0F
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#define STK8BA50_REG_BWSEL 0x10
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#define STK8BA50_REG_POWMODE 0x11
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#define STK8BA50_REG_SWRST 0x14
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#define STK8BA50_REG_INTEN2 0x17
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#define STK8BA50_REG_INTMAP2 0x1A
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#define STK8BA50_MODE_NORMAL 0
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#define STK8BA50_MODE_SUSPEND 1
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#define STK8BA50_MODE_POWERBIT BIT(7)
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#define STK8BA50_DATA_SHIFT 6
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#define STK8BA50_RESET_CMD 0xB6
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#define STK8BA50_SR_1792HZ_IDX 7
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#define STK8BA50_DREADY_INT_MASK 0x10
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#define STK8BA50_DREADY_INT_MAP 0x81
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#define STK8BA50_ALL_CHANNEL_MASK 7
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#define STK8BA50_ALL_CHANNEL_SIZE 6
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#define STK8BA50_DRIVER_NAME "stk8ba50"
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#define STK8BA50_IRQ_NAME "stk8ba50_event"
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#define STK8BA50_SCALE_AVAIL "0.0384 0.0767 0.1534 0.3069"
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/*
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* The accelerometer has four measurement ranges:
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* +/-2g; +/-4g; +/-8g; +/-16g
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*
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* Acceleration values are 10-bit, 2's complement.
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* Scales are calculated as following:
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*
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* scale1 = (2 + 2) * 9.81 / (2^10 - 1) = 0.0384
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* scale2 = (4 + 4) * 9.81 / (2^10 - 1) = 0.0767
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* etc.
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*
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* Scales are stored in this format:
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* { <register value>, <scale value> }
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*
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* Locally, the range is stored as a table index.
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*/
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static const struct {
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u8 reg_val;
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u32 scale_val;
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} stk8ba50_scale_table[] = {
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{3, 38400}, {5, 76700}, {8, 153400}, {12, 306900}
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};
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/* Sample rates are stored as { <register value>, <Hz value> } */
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static const struct {
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u8 reg_val;
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u16 samp_freq;
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} stk8ba50_samp_freq_table[] = {
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{0x08, 14}, {0x09, 25}, {0x0A, 56}, {0x0B, 112},
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{0x0C, 224}, {0x0D, 448}, {0x0E, 896}, {0x0F, 1792}
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};
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/* Used to map scan mask bits to their corresponding channel register. */
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static const int stk8ba50_channel_table[] = {
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STK8BA50_REG_XOUT,
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STK8BA50_REG_YOUT,
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STK8BA50_REG_ZOUT
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};
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struct stk8ba50_data {
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struct i2c_client *client;
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struct mutex lock;
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int range;
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u8 sample_rate_idx;
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struct iio_trigger *dready_trig;
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bool dready_trigger_on;
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/* Ensure timestamp is naturally aligned */
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struct {
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s16 chans[3];
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s64 timetamp __aligned(8);
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} scan;
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};
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#define STK8BA50_ACCEL_CHANNEL(index, reg, axis) { \
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.type = IIO_ACCEL, \
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.address = reg, \
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.modified = 1, \
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.channel2 = IIO_MOD_##axis, \
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.info_mask_separate = BIT(IIO_CHAN_INFO_RAW), \
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.info_mask_shared_by_type = BIT(IIO_CHAN_INFO_SCALE), \
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BIT(IIO_CHAN_INFO_SAMP_FREQ), \
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.scan_index = index, \
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.scan_type = { \
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.sign = 's', \
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.realbits = 10, \
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.storagebits = 16, \
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.shift = STK8BA50_DATA_SHIFT, \
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.endianness = IIO_CPU, \
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}, \
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}
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static const struct iio_chan_spec stk8ba50_channels[] = {
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STK8BA50_ACCEL_CHANNEL(0, STK8BA50_REG_XOUT, X),
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STK8BA50_ACCEL_CHANNEL(1, STK8BA50_REG_YOUT, Y),
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STK8BA50_ACCEL_CHANNEL(2, STK8BA50_REG_ZOUT, Z),
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IIO_CHAN_SOFT_TIMESTAMP(3),
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};
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static IIO_CONST_ATTR(in_accel_scale_available, STK8BA50_SCALE_AVAIL);
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static IIO_CONST_ATTR_SAMP_FREQ_AVAIL("14 25 56 112 224 448 896 1792");
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static struct attribute *stk8ba50_attributes[] = {
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&iio_const_attr_in_accel_scale_available.dev_attr.attr,
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&iio_const_attr_sampling_frequency_available.dev_attr.attr,
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NULL,
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};
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static const struct attribute_group stk8ba50_attribute_group = {
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.attrs = stk8ba50_attributes
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};
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static int stk8ba50_read_accel(struct stk8ba50_data *data, u8 reg)
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{
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int ret;
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struct i2c_client *client = data->client;
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ret = i2c_smbus_read_word_data(client, reg);
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if (ret < 0) {
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dev_err(&client->dev, "register read failed\n");
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return ret;
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}
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return ret;
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}
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static int stk8ba50_data_rdy_trigger_set_state(struct iio_trigger *trig,
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bool state)
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{
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struct iio_dev *indio_dev = iio_trigger_get_drvdata(trig);
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struct stk8ba50_data *data = iio_priv(indio_dev);
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int ret;
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if (state)
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ret = i2c_smbus_write_byte_data(data->client,
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STK8BA50_REG_INTEN2, STK8BA50_DREADY_INT_MASK);
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else
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ret = i2c_smbus_write_byte_data(data->client,
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STK8BA50_REG_INTEN2, 0x00);
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if (ret < 0)
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dev_err(&data->client->dev, "failed to set trigger state\n");
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else
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data->dready_trigger_on = state;
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return ret;
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}
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static const struct iio_trigger_ops stk8ba50_trigger_ops = {
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.set_trigger_state = stk8ba50_data_rdy_trigger_set_state,
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};
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static int stk8ba50_set_power(struct stk8ba50_data *data, bool mode)
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{
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int ret;
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u8 masked_reg;
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struct i2c_client *client = data->client;
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ret = i2c_smbus_read_byte_data(client, STK8BA50_REG_POWMODE);
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if (ret < 0)
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goto exit_err;
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if (mode)
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masked_reg = ret | STK8BA50_MODE_POWERBIT;
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else
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masked_reg = ret & (~STK8BA50_MODE_POWERBIT);
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ret = i2c_smbus_write_byte_data(client, STK8BA50_REG_POWMODE,
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masked_reg);
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if (ret < 0)
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goto exit_err;
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return ret;
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exit_err:
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dev_err(&client->dev, "failed to change sensor mode\n");
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return ret;
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}
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static int stk8ba50_read_raw(struct iio_dev *indio_dev,
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struct iio_chan_spec const *chan,
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int *val, int *val2, long mask)
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{
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struct stk8ba50_data *data = iio_priv(indio_dev);
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int ret;
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switch (mask) {
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case IIO_CHAN_INFO_RAW:
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if (iio_buffer_enabled(indio_dev))
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return -EBUSY;
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mutex_lock(&data->lock);
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ret = stk8ba50_set_power(data, STK8BA50_MODE_NORMAL);
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if (ret < 0) {
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mutex_unlock(&data->lock);
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return -EINVAL;
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}
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ret = stk8ba50_read_accel(data, chan->address);
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if (ret < 0) {
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stk8ba50_set_power(data, STK8BA50_MODE_SUSPEND);
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mutex_unlock(&data->lock);
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return -EINVAL;
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}
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*val = sign_extend32(ret >> chan->scan_type.shift,
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chan->scan_type.realbits - 1);
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stk8ba50_set_power(data, STK8BA50_MODE_SUSPEND);
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mutex_unlock(&data->lock);
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return IIO_VAL_INT;
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case IIO_CHAN_INFO_SCALE:
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*val = 0;
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*val2 = stk8ba50_scale_table[data->range].scale_val;
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return IIO_VAL_INT_PLUS_MICRO;
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case IIO_CHAN_INFO_SAMP_FREQ:
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*val = stk8ba50_samp_freq_table
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[data->sample_rate_idx].samp_freq;
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*val2 = 0;
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return IIO_VAL_INT;
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}
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return -EINVAL;
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}
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static int stk8ba50_write_raw(struct iio_dev *indio_dev,
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struct iio_chan_spec const *chan,
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int val, int val2, long mask)
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{
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int ret;
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int i;
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int index = -1;
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struct stk8ba50_data *data = iio_priv(indio_dev);
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switch (mask) {
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case IIO_CHAN_INFO_SCALE:
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if (val != 0)
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return -EINVAL;
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for (i = 0; i < ARRAY_SIZE(stk8ba50_scale_table); i++)
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if (val2 == stk8ba50_scale_table[i].scale_val) {
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index = i;
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break;
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}
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if (index < 0)
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return -EINVAL;
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ret = i2c_smbus_write_byte_data(data->client,
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STK8BA50_REG_RANGE,
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stk8ba50_scale_table[index].reg_val);
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if (ret < 0)
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dev_err(&data->client->dev,
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"failed to set measurement range\n");
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else
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data->range = index;
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return ret;
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case IIO_CHAN_INFO_SAMP_FREQ:
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for (i = 0; i < ARRAY_SIZE(stk8ba50_samp_freq_table); i++)
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if (val == stk8ba50_samp_freq_table[i].samp_freq) {
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index = i;
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break;
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}
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if (index < 0)
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return -EINVAL;
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ret = i2c_smbus_write_byte_data(data->client,
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STK8BA50_REG_BWSEL,
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stk8ba50_samp_freq_table[index].reg_val);
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if (ret < 0)
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dev_err(&data->client->dev,
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"failed to set sampling rate\n");
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else
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data->sample_rate_idx = index;
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return ret;
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}
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return -EINVAL;
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}
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static const struct iio_info stk8ba50_info = {
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.read_raw = stk8ba50_read_raw,
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.write_raw = stk8ba50_write_raw,
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.attrs = &stk8ba50_attribute_group,
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};
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static irqreturn_t stk8ba50_trigger_handler(int irq, void *p)
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{
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struct iio_poll_func *pf = p;
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struct iio_dev *indio_dev = pf->indio_dev;
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struct stk8ba50_data *data = iio_priv(indio_dev);
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int bit, ret, i = 0;
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mutex_lock(&data->lock);
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/*
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* Do a bulk read if all channels are requested,
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* from 0x02 (XOUT1) to 0x07 (ZOUT2)
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*/
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if (*(indio_dev->active_scan_mask) == STK8BA50_ALL_CHANNEL_MASK) {
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ret = i2c_smbus_read_i2c_block_data(data->client,
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STK8BA50_REG_XOUT,
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STK8BA50_ALL_CHANNEL_SIZE,
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(u8 *)data->scan.chans);
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if (ret < STK8BA50_ALL_CHANNEL_SIZE) {
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dev_err(&data->client->dev, "register read failed\n");
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goto err;
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}
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} else {
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for_each_set_bit(bit, indio_dev->active_scan_mask,
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indio_dev->masklength) {
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ret = stk8ba50_read_accel(data,
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stk8ba50_channel_table[bit]);
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if (ret < 0)
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goto err;
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data->scan.chans[i++] = ret;
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}
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}
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iio_push_to_buffers_with_timestamp(indio_dev, &data->scan,
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pf->timestamp);
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err:
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mutex_unlock(&data->lock);
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iio_trigger_notify_done(indio_dev->trig);
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return IRQ_HANDLED;
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}
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static irqreturn_t stk8ba50_data_rdy_trig_poll(int irq, void *private)
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{
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struct iio_dev *indio_dev = private;
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struct stk8ba50_data *data = iio_priv(indio_dev);
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if (data->dready_trigger_on)
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iio_trigger_poll(data->dready_trig);
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return IRQ_HANDLED;
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}
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static int stk8ba50_buffer_preenable(struct iio_dev *indio_dev)
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{
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struct stk8ba50_data *data = iio_priv(indio_dev);
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return stk8ba50_set_power(data, STK8BA50_MODE_NORMAL);
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}
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static int stk8ba50_buffer_postdisable(struct iio_dev *indio_dev)
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{
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struct stk8ba50_data *data = iio_priv(indio_dev);
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return stk8ba50_set_power(data, STK8BA50_MODE_SUSPEND);
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}
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static const struct iio_buffer_setup_ops stk8ba50_buffer_setup_ops = {
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.preenable = stk8ba50_buffer_preenable,
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.postdisable = stk8ba50_buffer_postdisable,
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};
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static int stk8ba50_probe(struct i2c_client *client)
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{
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int ret;
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struct iio_dev *indio_dev;
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struct stk8ba50_data *data;
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indio_dev = devm_iio_device_alloc(&client->dev, sizeof(*data));
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if (!indio_dev) {
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dev_err(&client->dev, "iio allocation failed!\n");
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return -ENOMEM;
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}
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data = iio_priv(indio_dev);
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data->client = client;
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i2c_set_clientdata(client, indio_dev);
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mutex_init(&data->lock);
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indio_dev->info = &stk8ba50_info;
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indio_dev->name = STK8BA50_DRIVER_NAME;
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indio_dev->modes = INDIO_DIRECT_MODE;
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indio_dev->channels = stk8ba50_channels;
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indio_dev->num_channels = ARRAY_SIZE(stk8ba50_channels);
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/* Reset all registers on startup */
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ret = i2c_smbus_write_byte_data(client,
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STK8BA50_REG_SWRST, STK8BA50_RESET_CMD);
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if (ret < 0) {
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dev_err(&client->dev, "failed to reset sensor\n");
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goto err_power_off;
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}
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/* The default range is +/-2g */
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data->range = 0;
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/* The default sampling rate is 1792 Hz (maximum) */
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data->sample_rate_idx = STK8BA50_SR_1792HZ_IDX;
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/* Set up interrupts */
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ret = i2c_smbus_write_byte_data(client,
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STK8BA50_REG_INTEN2, STK8BA50_DREADY_INT_MASK);
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if (ret < 0) {
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dev_err(&client->dev, "failed to set up interrupts\n");
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goto err_power_off;
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}
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ret = i2c_smbus_write_byte_data(client,
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STK8BA50_REG_INTMAP2, STK8BA50_DREADY_INT_MAP);
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if (ret < 0) {
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dev_err(&client->dev, "failed to set up interrupts\n");
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goto err_power_off;
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}
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if (client->irq > 0) {
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ret = devm_request_threaded_irq(&client->dev, client->irq,
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stk8ba50_data_rdy_trig_poll,
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NULL,
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IRQF_TRIGGER_RISING |
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IRQF_ONESHOT,
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STK8BA50_IRQ_NAME,
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indio_dev);
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if (ret < 0) {
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dev_err(&client->dev, "request irq %d failed\n",
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client->irq);
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goto err_power_off;
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}
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data->dready_trig = devm_iio_trigger_alloc(&client->dev,
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"%s-dev%d",
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indio_dev->name,
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iio_device_id(indio_dev));
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if (!data->dready_trig) {
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ret = -ENOMEM;
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goto err_power_off;
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}
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data->dready_trig->ops = &stk8ba50_trigger_ops;
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iio_trigger_set_drvdata(data->dready_trig, indio_dev);
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ret = iio_trigger_register(data->dready_trig);
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if (ret) {
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dev_err(&client->dev, "iio trigger register failed\n");
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goto err_power_off;
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}
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}
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ret = iio_triggered_buffer_setup(indio_dev,
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iio_pollfunc_store_time,
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stk8ba50_trigger_handler,
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&stk8ba50_buffer_setup_ops);
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if (ret < 0) {
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dev_err(&client->dev, "iio triggered buffer setup failed\n");
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goto err_trigger_unregister;
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}
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ret = iio_device_register(indio_dev);
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if (ret < 0) {
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dev_err(&client->dev, "device_register failed\n");
|
|
goto err_buffer_cleanup;
|
|
}
|
|
|
|
return ret;
|
|
|
|
err_buffer_cleanup:
|
|
iio_triggered_buffer_cleanup(indio_dev);
|
|
err_trigger_unregister:
|
|
if (data->dready_trig)
|
|
iio_trigger_unregister(data->dready_trig);
|
|
err_power_off:
|
|
stk8ba50_set_power(data, STK8BA50_MODE_SUSPEND);
|
|
return ret;
|
|
}
|
|
|
|
static void stk8ba50_remove(struct i2c_client *client)
|
|
{
|
|
struct iio_dev *indio_dev = i2c_get_clientdata(client);
|
|
struct stk8ba50_data *data = iio_priv(indio_dev);
|
|
|
|
iio_device_unregister(indio_dev);
|
|
iio_triggered_buffer_cleanup(indio_dev);
|
|
|
|
if (data->dready_trig)
|
|
iio_trigger_unregister(data->dready_trig);
|
|
|
|
stk8ba50_set_power(data, STK8BA50_MODE_SUSPEND);
|
|
}
|
|
|
|
static int stk8ba50_suspend(struct device *dev)
|
|
{
|
|
struct stk8ba50_data *data;
|
|
|
|
data = iio_priv(i2c_get_clientdata(to_i2c_client(dev)));
|
|
|
|
return stk8ba50_set_power(data, STK8BA50_MODE_SUSPEND);
|
|
}
|
|
|
|
static int stk8ba50_resume(struct device *dev)
|
|
{
|
|
struct stk8ba50_data *data;
|
|
|
|
data = iio_priv(i2c_get_clientdata(to_i2c_client(dev)));
|
|
|
|
return stk8ba50_set_power(data, STK8BA50_MODE_NORMAL);
|
|
}
|
|
|
|
static DEFINE_SIMPLE_DEV_PM_OPS(stk8ba50_pm_ops, stk8ba50_suspend,
|
|
stk8ba50_resume);
|
|
|
|
static const struct i2c_device_id stk8ba50_i2c_id[] = {
|
|
{"stk8ba50", 0},
|
|
{}
|
|
};
|
|
MODULE_DEVICE_TABLE(i2c, stk8ba50_i2c_id);
|
|
|
|
static const struct acpi_device_id stk8ba50_acpi_id[] = {
|
|
{"STK8BA50", 0},
|
|
{}
|
|
};
|
|
|
|
MODULE_DEVICE_TABLE(acpi, stk8ba50_acpi_id);
|
|
|
|
static struct i2c_driver stk8ba50_driver = {
|
|
.driver = {
|
|
.name = "stk8ba50",
|
|
.pm = pm_sleep_ptr(&stk8ba50_pm_ops),
|
|
.acpi_match_table = ACPI_PTR(stk8ba50_acpi_id),
|
|
},
|
|
.probe_new = stk8ba50_probe,
|
|
.remove = stk8ba50_remove,
|
|
.id_table = stk8ba50_i2c_id,
|
|
};
|
|
|
|
module_i2c_driver(stk8ba50_driver);
|
|
|
|
MODULE_AUTHOR("Tiberiu Breana <tiberiu.a.breana@intel.com>");
|
|
MODULE_DESCRIPTION("STK8BA50 3-Axis Accelerometer driver");
|
|
MODULE_LICENSE("GPL v2");
|