![Jonathan Cameron](/assets/img/avatar_default.png)
The equivalent of both of these are now done via macro magic when the relevant register calls are made. The actual structure elements will shortly go away. Signed-off-by: Jonathan Cameron <Jonathan.Cameron@huawei.com> Reviewed-by: Lars-Peter Clausen <lars@metafoo.de>
564 lines
14 KiB
C
564 lines
14 KiB
C
/*
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* srf08.c - Support for Devantech SRFxx ultrasonic ranger
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* with i2c interface
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* actually supported are srf02, srf08, srf10
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*
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* Copyright (c) 2016, 2017 Andreas Klinger <ak@it-klinger.de>
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*
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* This file is subject to the terms and conditions of version 2 of
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* the GNU General Public License. See the file COPYING in the main
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* directory of this archive for more details.
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*
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* For details about the device see:
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* http://www.robot-electronics.co.uk/htm/srf08tech.html
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* http://www.robot-electronics.co.uk/htm/srf10tech.htm
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* http://www.robot-electronics.co.uk/htm/srf02tech.htm
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*/
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#include <linux/err.h>
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#include <linux/i2c.h>
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#include <linux/delay.h>
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#include <linux/module.h>
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#include <linux/bitops.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/buffer.h>
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#include <linux/iio/trigger_consumer.h>
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#include <linux/iio/triggered_buffer.h>
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/* registers of SRF08 device */
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#define SRF08_WRITE_COMMAND 0x00 /* Command Register */
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#define SRF08_WRITE_MAX_GAIN 0x01 /* Max Gain Register: 0 .. 31 */
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#define SRF08_WRITE_RANGE 0x02 /* Range Register: 0 .. 255 */
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#define SRF08_READ_SW_REVISION 0x00 /* Software Revision */
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#define SRF08_READ_LIGHT 0x01 /* Light Sensor during last echo */
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#define SRF08_READ_ECHO_1_HIGH 0x02 /* Range of first echo received */
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#define SRF08_READ_ECHO_1_LOW 0x03 /* Range of first echo received */
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#define SRF08_CMD_RANGING_CM 0x51 /* Ranging Mode - Result in cm */
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enum srf08_sensor_type {
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SRF02,
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SRF08,
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SRF10,
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SRF_MAX_TYPE
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};
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struct srf08_chip_info {
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const int *sensitivity_avail;
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int num_sensitivity_avail;
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int sensitivity_default;
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/* default value of Range in mm */
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int range_default;
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};
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struct srf08_data {
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struct i2c_client *client;
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/*
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* Gain in the datasheet is called sensitivity here to distinct it
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* from the gain used with amplifiers of adc's
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*/
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int sensitivity;
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/* max. Range in mm */
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int range_mm;
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struct mutex lock;
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/*
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* triggered buffer
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* 1x16-bit channel + 3x16 padding + 4x16 timestamp
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*/
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s16 buffer[8];
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/* Sensor-Type */
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enum srf08_sensor_type sensor_type;
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/* Chip-specific information */
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const struct srf08_chip_info *chip_info;
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};
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/*
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* in the documentation one can read about the "Gain" of the device
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* which is used here for amplifying the signal and filtering out unwanted
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* ones.
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* But with ADC's this term is already used differently and that's why it
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* is called "Sensitivity" here.
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*/
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static const struct srf08_chip_info srf02_chip_info = {
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.sensitivity_avail = NULL,
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.num_sensitivity_avail = 0,
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.sensitivity_default = 0,
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.range_default = 0,
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};
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static const int srf08_sensitivity_avail[] = {
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94, 97, 100, 103, 107, 110, 114, 118,
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123, 128, 133, 139, 145, 152, 159, 168,
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177, 187, 199, 212, 227, 245, 265, 288,
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317, 352, 395, 450, 524, 626, 777, 1025
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};
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static const struct srf08_chip_info srf08_chip_info = {
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.sensitivity_avail = srf08_sensitivity_avail,
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.num_sensitivity_avail = ARRAY_SIZE(srf08_sensitivity_avail),
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.sensitivity_default = 1025,
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.range_default = 6020,
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};
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static const int srf10_sensitivity_avail[] = {
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40, 40, 50, 60, 70, 80, 100, 120,
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140, 200, 250, 300, 350, 400, 500, 600,
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700,
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};
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static const struct srf08_chip_info srf10_chip_info = {
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.sensitivity_avail = srf10_sensitivity_avail,
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.num_sensitivity_avail = ARRAY_SIZE(srf10_sensitivity_avail),
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.sensitivity_default = 700,
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.range_default = 6020,
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};
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static int srf08_read_ranging(struct srf08_data *data)
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{
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struct i2c_client *client = data->client;
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int ret, i;
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int waittime;
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mutex_lock(&data->lock);
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ret = i2c_smbus_write_byte_data(data->client,
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SRF08_WRITE_COMMAND, SRF08_CMD_RANGING_CM);
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if (ret < 0) {
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dev_err(&client->dev, "write command - err: %d\n", ret);
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mutex_unlock(&data->lock);
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return ret;
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}
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/*
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* we read here until a correct version number shows up as
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* suggested by the documentation
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*
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* with an ultrasonic speed of 343 m/s and a roundtrip of it
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* sleep the expected duration and try to read from the device
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* if nothing useful is read try it in a shorter grid
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*
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* polling for not more than 20 ms should be enough
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*/
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waittime = 1 + data->range_mm / 172;
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msleep(waittime);
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for (i = 0; i < 4; i++) {
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ret = i2c_smbus_read_byte_data(data->client,
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SRF08_READ_SW_REVISION);
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/* check if a valid version number is read */
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if (ret < 255 && ret > 0)
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break;
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msleep(5);
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}
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if (ret >= 255 || ret <= 0) {
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dev_err(&client->dev, "device not ready\n");
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mutex_unlock(&data->lock);
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return -EIO;
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}
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ret = i2c_smbus_read_word_swapped(data->client,
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SRF08_READ_ECHO_1_HIGH);
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if (ret < 0) {
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dev_err(&client->dev, "cannot read distance: ret=%d\n", ret);
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mutex_unlock(&data->lock);
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return ret;
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}
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mutex_unlock(&data->lock);
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return ret;
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}
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static irqreturn_t srf08_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 srf08_data *data = iio_priv(indio_dev);
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s16 sensor_data;
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sensor_data = srf08_read_ranging(data);
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if (sensor_data < 0)
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goto err;
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mutex_lock(&data->lock);
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data->buffer[0] = sensor_data;
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iio_push_to_buffers_with_timestamp(indio_dev,
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data->buffer, pf->timestamp);
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mutex_unlock(&data->lock);
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err:
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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 int srf08_read_raw(struct iio_dev *indio_dev,
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struct iio_chan_spec const *channel, int *val,
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int *val2, long mask)
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{
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struct srf08_data *data = iio_priv(indio_dev);
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int ret;
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if (channel->type != IIO_DISTANCE)
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return -EINVAL;
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switch (mask) {
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case IIO_CHAN_INFO_RAW:
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ret = srf08_read_ranging(data);
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if (ret < 0)
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return ret;
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*val = ret;
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return IIO_VAL_INT;
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case IIO_CHAN_INFO_SCALE:
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/* 1 LSB is 1 cm */
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*val = 0;
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*val2 = 10000;
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return IIO_VAL_INT_PLUS_MICRO;
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default:
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return -EINVAL;
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}
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}
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static ssize_t srf08_show_range_mm_available(struct device *dev,
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struct device_attribute *attr, char *buf)
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{
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return sprintf(buf, "[0.043 0.043 11.008]\n");
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}
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static IIO_DEVICE_ATTR(sensor_max_range_available, S_IRUGO,
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srf08_show_range_mm_available, NULL, 0);
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static ssize_t srf08_show_range_mm(struct device *dev,
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struct device_attribute *attr, char *buf)
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{
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struct iio_dev *indio_dev = dev_to_iio_dev(dev);
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struct srf08_data *data = iio_priv(indio_dev);
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return sprintf(buf, "%d.%03d\n", data->range_mm / 1000,
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data->range_mm % 1000);
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}
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/*
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* set the range of the sensor to an even multiple of 43 mm
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* which corresponds to 1 LSB in the register
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*
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* register value corresponding range
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* 0x00 43 mm
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* 0x01 86 mm
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* 0x02 129 mm
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* ...
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* 0xFF 11008 mm
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*/
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static ssize_t srf08_write_range_mm(struct srf08_data *data, unsigned int val)
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{
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int ret;
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struct i2c_client *client = data->client;
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unsigned int mod;
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u8 regval;
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ret = val / 43 - 1;
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mod = val % 43;
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if (mod || (ret < 0) || (ret > 255))
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return -EINVAL;
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regval = ret;
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mutex_lock(&data->lock);
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ret = i2c_smbus_write_byte_data(client, SRF08_WRITE_RANGE, regval);
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if (ret < 0) {
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dev_err(&client->dev, "write_range - err: %d\n", ret);
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mutex_unlock(&data->lock);
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return ret;
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}
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data->range_mm = val;
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mutex_unlock(&data->lock);
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return 0;
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}
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static ssize_t srf08_store_range_mm(struct device *dev,
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struct device_attribute *attr,
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const char *buf, size_t len)
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{
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struct iio_dev *indio_dev = dev_to_iio_dev(dev);
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struct srf08_data *data = iio_priv(indio_dev);
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int ret;
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int integer, fract;
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ret = iio_str_to_fixpoint(buf, 100, &integer, &fract);
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if (ret)
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return ret;
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ret = srf08_write_range_mm(data, integer * 1000 + fract);
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if (ret < 0)
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return ret;
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return len;
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}
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static IIO_DEVICE_ATTR(sensor_max_range, S_IRUGO | S_IWUSR,
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srf08_show_range_mm, srf08_store_range_mm, 0);
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static ssize_t srf08_show_sensitivity_available(struct device *dev,
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struct device_attribute *attr, char *buf)
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{
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int i, len = 0;
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struct iio_dev *indio_dev = dev_to_iio_dev(dev);
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struct srf08_data *data = iio_priv(indio_dev);
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for (i = 0; i < data->chip_info->num_sensitivity_avail; i++)
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if (data->chip_info->sensitivity_avail[i])
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len += sprintf(buf + len, "%d ",
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data->chip_info->sensitivity_avail[i]);
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len += sprintf(buf + len, "\n");
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return len;
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}
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static IIO_DEVICE_ATTR(sensor_sensitivity_available, S_IRUGO,
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srf08_show_sensitivity_available, NULL, 0);
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static ssize_t srf08_show_sensitivity(struct device *dev,
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struct device_attribute *attr, char *buf)
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{
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struct iio_dev *indio_dev = dev_to_iio_dev(dev);
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struct srf08_data *data = iio_priv(indio_dev);
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int len;
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len = sprintf(buf, "%d\n", data->sensitivity);
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return len;
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}
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static ssize_t srf08_write_sensitivity(struct srf08_data *data,
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unsigned int val)
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{
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struct i2c_client *client = data->client;
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int ret, i;
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u8 regval;
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if (!val)
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return -EINVAL;
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for (i = 0; i < data->chip_info->num_sensitivity_avail; i++)
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if (val && (val == data->chip_info->sensitivity_avail[i])) {
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regval = i;
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break;
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}
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if (i >= data->chip_info->num_sensitivity_avail)
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return -EINVAL;
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mutex_lock(&data->lock);
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ret = i2c_smbus_write_byte_data(client, SRF08_WRITE_MAX_GAIN, regval);
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if (ret < 0) {
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dev_err(&client->dev, "write_sensitivity - err: %d\n", ret);
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mutex_unlock(&data->lock);
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return ret;
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}
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data->sensitivity = val;
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mutex_unlock(&data->lock);
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return 0;
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}
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static ssize_t srf08_store_sensitivity(struct device *dev,
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struct device_attribute *attr,
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const char *buf, size_t len)
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{
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struct iio_dev *indio_dev = dev_to_iio_dev(dev);
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struct srf08_data *data = iio_priv(indio_dev);
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int ret;
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unsigned int val;
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ret = kstrtouint(buf, 10, &val);
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if (ret)
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return ret;
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ret = srf08_write_sensitivity(data, val);
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if (ret < 0)
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return ret;
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return len;
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}
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static IIO_DEVICE_ATTR(sensor_sensitivity, S_IRUGO | S_IWUSR,
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srf08_show_sensitivity, srf08_store_sensitivity, 0);
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static struct attribute *srf08_attributes[] = {
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&iio_dev_attr_sensor_max_range.dev_attr.attr,
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&iio_dev_attr_sensor_max_range_available.dev_attr.attr,
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&iio_dev_attr_sensor_sensitivity.dev_attr.attr,
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&iio_dev_attr_sensor_sensitivity_available.dev_attr.attr,
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NULL,
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};
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static const struct attribute_group srf08_attribute_group = {
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.attrs = srf08_attributes,
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};
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static const struct iio_chan_spec srf08_channels[] = {
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{
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.type = IIO_DISTANCE,
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.info_mask_separate =
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BIT(IIO_CHAN_INFO_RAW) |
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BIT(IIO_CHAN_INFO_SCALE),
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.scan_index = 0,
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.scan_type = {
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.sign = 's',
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.realbits = 16,
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.storagebits = 16,
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.endianness = IIO_CPU,
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},
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},
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IIO_CHAN_SOFT_TIMESTAMP(1),
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};
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static const struct iio_info srf08_info = {
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.read_raw = srf08_read_raw,
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.attrs = &srf08_attribute_group,
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};
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/*
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* srf02 don't have an adjustable range or sensitivity,
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* so we don't need attributes at all
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*/
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static const struct iio_info srf02_info = {
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.read_raw = srf08_read_raw,
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};
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static int srf08_probe(struct i2c_client *client,
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const struct i2c_device_id *id)
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{
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struct iio_dev *indio_dev;
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struct srf08_data *data;
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int ret;
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if (!i2c_check_functionality(client->adapter,
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I2C_FUNC_SMBUS_READ_BYTE_DATA |
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I2C_FUNC_SMBUS_WRITE_BYTE_DATA |
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I2C_FUNC_SMBUS_READ_WORD_DATA))
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return -ENODEV;
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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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return -ENOMEM;
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data = iio_priv(indio_dev);
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i2c_set_clientdata(client, indio_dev);
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data->client = client;
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data->sensor_type = (enum srf08_sensor_type)id->driver_data;
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switch (data->sensor_type) {
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case SRF02:
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data->chip_info = &srf02_chip_info;
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indio_dev->info = &srf02_info;
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break;
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case SRF08:
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data->chip_info = &srf08_chip_info;
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indio_dev->info = &srf08_info;
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break;
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case SRF10:
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data->chip_info = &srf10_chip_info;
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indio_dev->info = &srf08_info;
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break;
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default:
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return -EINVAL;
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}
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indio_dev->name = id->name;
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indio_dev->dev.parent = &client->dev;
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indio_dev->modes = INDIO_DIRECT_MODE;
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indio_dev->channels = srf08_channels;
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indio_dev->num_channels = ARRAY_SIZE(srf08_channels);
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mutex_init(&data->lock);
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ret = devm_iio_triggered_buffer_setup(&client->dev, indio_dev,
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iio_pollfunc_store_time, srf08_trigger_handler, NULL);
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if (ret < 0) {
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dev_err(&client->dev, "setup of iio triggered buffer failed\n");
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return ret;
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}
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if (data->chip_info->range_default) {
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/*
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* set default range of device in mm here
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* these register values cannot be read from the hardware
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* therefore set driver specific default values
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*
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* srf02 don't have a default value so it'll be omitted
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*/
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ret = srf08_write_range_mm(data,
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data->chip_info->range_default);
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if (ret < 0)
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return ret;
|
|
}
|
|
|
|
if (data->chip_info->sensitivity_default) {
|
|
/*
|
|
* set default sensitivity of device here
|
|
* these register values cannot be read from the hardware
|
|
* therefore set driver specific default values
|
|
*
|
|
* srf02 don't have a default value so it'll be omitted
|
|
*/
|
|
ret = srf08_write_sensitivity(data,
|
|
data->chip_info->sensitivity_default);
|
|
if (ret < 0)
|
|
return ret;
|
|
}
|
|
|
|
return devm_iio_device_register(&client->dev, indio_dev);
|
|
}
|
|
|
|
static const struct of_device_id of_srf08_match[] = {
|
|
{ .compatible = "devantech,srf02", (void *)SRF02},
|
|
{ .compatible = "devantech,srf08", (void *)SRF08},
|
|
{ .compatible = "devantech,srf10", (void *)SRF10},
|
|
{},
|
|
};
|
|
|
|
MODULE_DEVICE_TABLE(of, of_srf08_match);
|
|
|
|
static const struct i2c_device_id srf08_id[] = {
|
|
{ "srf02", SRF02 },
|
|
{ "srf08", SRF08 },
|
|
{ "srf10", SRF10 },
|
|
{ }
|
|
};
|
|
MODULE_DEVICE_TABLE(i2c, srf08_id);
|
|
|
|
static struct i2c_driver srf08_driver = {
|
|
.driver = {
|
|
.name = "srf08",
|
|
.of_match_table = of_srf08_match,
|
|
},
|
|
.probe = srf08_probe,
|
|
.id_table = srf08_id,
|
|
};
|
|
module_i2c_driver(srf08_driver);
|
|
|
|
MODULE_AUTHOR("Andreas Klinger <ak@it-klinger.de>");
|
|
MODULE_DESCRIPTION("Devantech SRF02/SRF08/SRF10 i2c ultrasonic ranger driver");
|
|
MODULE_LICENSE("GPL");
|