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iio: sps30: separate core and interface specific code
Move code responsible for handling i2c communication to a separate file. Rationale for this change is preparation for adding support for serial communication. Signed-off-by: Tomasz Duszynski <tomasz.duszynski@octakon.com> Signed-off-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>
This commit is contained in:
parent
101af4c20c
commit
8f3f130852
@ -16484,6 +16484,7 @@ M: Tomasz Duszynski <tduszyns@gmail.com>
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S: Maintained
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F: Documentation/devicetree/bindings/iio/chemical/sensirion,sps30.yaml
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F: drivers/iio/chemical/sps30.c
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F: drivers/iio/chemical/sps30_i2c.c
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SERIAL DEVICE BUS
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M: Rob Herring <robh@kernel.org>
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@ -132,17 +132,21 @@ config SENSIRION_SGP30
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module will be called sgp30.
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config SPS30
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tristate "SPS30 particulate matter sensor"
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depends on I2C
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select CRC8
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tristate
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select IIO_BUFFER
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select IIO_TRIGGERED_BUFFER
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config SPS30_I2C
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tristate "SPS30 particulate matter sensor I2C driver"
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depends on I2C
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select SPS30
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select CRC8
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help
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Say Y here to build support for the Sensirion SPS30 particulate
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matter sensor.
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Say Y here to build support for the Sensirion SPS30 I2C interface
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driver.
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To compile this driver as a module, choose M here: the module will
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be called sps30.
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be called sps30_i2c.
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config VZ89X
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tristate "SGX Sensortech MiCS VZ89X VOC sensor"
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@ -17,4 +17,5 @@ obj-$(CONFIG_SCD30_I2C) += scd30_i2c.o
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obj-$(CONFIG_SCD30_SERIAL) += scd30_serial.o
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obj-$(CONFIG_SENSIRION_SGP30) += sgp30.o
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obj-$(CONFIG_SPS30) += sps30.o
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obj-$(CONFIG_SPS30_I2C) += sps30_i2c.o
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obj-$(CONFIG_VZ89X) += vz89x.o
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@ -3,11 +3,8 @@
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* Sensirion SPS30 particulate matter sensor driver
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*
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* Copyright (c) Tomasz Duszynski <tduszyns@gmail.com>
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*
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* I2C slave address: 0x69
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*/
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#include <asm/unaligned.h>
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#include <linux/crc8.h>
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#include <linux/delay.h>
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#include <linux/i2c.h>
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@ -19,27 +16,14 @@
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#include <linux/kernel.h>
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#include <linux/module.h>
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#define SPS30_CRC8_POLYNOMIAL 0x31
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/* max number of bytes needed to store PM measurements or serial string */
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#define SPS30_MAX_READ_SIZE 48
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#include "sps30.h"
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/* sensor measures reliably up to 3000 ug / m3 */
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#define SPS30_MAX_PM 3000
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/* minimum and maximum self cleaning periods in seconds */
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#define SPS30_AUTO_CLEANING_PERIOD_MIN 0
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#define SPS30_AUTO_CLEANING_PERIOD_MAX 604800
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/* SPS30 commands */
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#define SPS30_START_MEAS 0x0010
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#define SPS30_STOP_MEAS 0x0104
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#define SPS30_RESET 0xd304
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#define SPS30_READ_DATA_READY_FLAG 0x0202
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#define SPS30_READ_DATA 0x0300
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#define SPS30_READ_SERIAL 0xd033
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#define SPS30_START_FAN_CLEANING 0x5607
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#define SPS30_AUTO_CLEANING_PERIOD 0x8004
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/* not a sensor command per se, used only to distinguish write from read */
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#define SPS30_READ_AUTO_CLEANING_PERIOD 0x8005
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enum {
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PM1,
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PM2P5,
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@ -52,114 +36,9 @@ enum {
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MEASURING,
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};
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struct sps30_state {
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struct i2c_client *client;
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/*
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* Guards against concurrent access to sensor registers.
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* Must be held whenever sequence of commands is to be executed.
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*/
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struct mutex lock;
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int state;
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};
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DECLARE_CRC8_TABLE(sps30_crc8_table);
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static int sps30_write_then_read(struct sps30_state *state, u8 *txbuf,
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int txsize, u8 *rxbuf, int rxsize)
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static s32 sps30_float_to_int_clamped(__be32 *fp)
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{
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int ret;
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/*
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* Sensor does not support repeated start so instead of
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* sending two i2c messages in a row we just send one by one.
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*/
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ret = i2c_master_send(state->client, txbuf, txsize);
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if (ret != txsize)
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return ret < 0 ? ret : -EIO;
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if (!rxbuf)
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return 0;
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ret = i2c_master_recv(state->client, rxbuf, rxsize);
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if (ret != rxsize)
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return ret < 0 ? ret : -EIO;
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return 0;
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}
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static int sps30_do_cmd(struct sps30_state *state, u16 cmd, u8 *data, int size)
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{
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/*
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* Internally sensor stores measurements in a following manner:
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*
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* PM1: upper two bytes, crc8, lower two bytes, crc8
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* PM2P5: upper two bytes, crc8, lower two bytes, crc8
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* PM4: upper two bytes, crc8, lower two bytes, crc8
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* PM10: upper two bytes, crc8, lower two bytes, crc8
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*
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* What follows next are number concentration measurements and
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* typical particle size measurement which we omit.
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*/
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u8 buf[SPS30_MAX_READ_SIZE] = { cmd >> 8, cmd };
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int i, ret = 0;
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switch (cmd) {
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case SPS30_START_MEAS:
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buf[2] = 0x03;
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buf[3] = 0x00;
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buf[4] = crc8(sps30_crc8_table, &buf[2], 2, CRC8_INIT_VALUE);
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ret = sps30_write_then_read(state, buf, 5, NULL, 0);
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break;
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case SPS30_STOP_MEAS:
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case SPS30_RESET:
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case SPS30_START_FAN_CLEANING:
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ret = sps30_write_then_read(state, buf, 2, NULL, 0);
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break;
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case SPS30_READ_AUTO_CLEANING_PERIOD:
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buf[0] = SPS30_AUTO_CLEANING_PERIOD >> 8;
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buf[1] = (u8)(SPS30_AUTO_CLEANING_PERIOD & 0xff);
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fallthrough;
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case SPS30_READ_DATA_READY_FLAG:
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case SPS30_READ_DATA:
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case SPS30_READ_SERIAL:
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/* every two data bytes are checksummed */
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size += size / 2;
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ret = sps30_write_then_read(state, buf, 2, buf, size);
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break;
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case SPS30_AUTO_CLEANING_PERIOD:
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buf[2] = data[0];
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buf[3] = data[1];
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buf[4] = crc8(sps30_crc8_table, &buf[2], 2, CRC8_INIT_VALUE);
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buf[5] = data[2];
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buf[6] = data[3];
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buf[7] = crc8(sps30_crc8_table, &buf[5], 2, CRC8_INIT_VALUE);
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ret = sps30_write_then_read(state, buf, 8, NULL, 0);
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break;
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}
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if (ret)
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return ret;
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/* validate received data and strip off crc bytes */
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for (i = 0; i < size; i += 3) {
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u8 crc = crc8(sps30_crc8_table, &buf[i], 2, CRC8_INIT_VALUE);
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if (crc != buf[i + 2]) {
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dev_err(&state->client->dev,
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"data integrity check failed\n");
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return -EIO;
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}
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*data++ = buf[i];
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*data++ = buf[i + 1];
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}
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return 0;
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}
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static s32 sps30_float_to_int_clamped(const u8 *fp)
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{
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int val = get_unaligned_be32(fp);
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int val = be32_to_cpup(fp);
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int mantissa = val & GENMASK(22, 0);
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/* this is fine since passed float is always non-negative */
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int exp = val >> 23;
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@ -188,38 +67,35 @@ static s32 sps30_float_to_int_clamped(const u8 *fp)
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static int sps30_do_meas(struct sps30_state *state, s32 *data, int size)
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{
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int i, ret, tries = 5;
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u8 tmp[16];
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int i, ret;
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if (state->state == RESET) {
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ret = sps30_do_cmd(state, SPS30_START_MEAS, NULL, 0);
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ret = state->ops->start_meas(state);
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if (ret)
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return ret;
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state->state = MEASURING;
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}
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while (tries--) {
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ret = sps30_do_cmd(state, SPS30_READ_DATA_READY_FLAG, tmp, 2);
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if (ret)
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return -EIO;
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/* new measurements ready to be read */
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if (tmp[1] == 1)
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break;
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msleep_interruptible(300);
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}
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if (tries == -1)
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return -ETIMEDOUT;
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ret = sps30_do_cmd(state, SPS30_READ_DATA, tmp, sizeof(int) * size);
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ret = state->ops->read_meas(state, (__be32 *)data, size);
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if (ret)
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return ret;
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for (i = 0; i < size; i++)
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data[i] = sps30_float_to_int_clamped(&tmp[4 * i]);
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data[i] = sps30_float_to_int_clamped((__be32 *)&data[i]);
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return 0;
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}
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static int sps30_do_reset(struct sps30_state *state)
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{
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int ret;
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ret = state->ops->reset(state);
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if (ret)
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return ret;
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state->state = RESET;
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return 0;
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}
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@ -310,24 +186,6 @@ static int sps30_read_raw(struct iio_dev *indio_dev,
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return -EINVAL;
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}
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static int sps30_do_cmd_reset(struct sps30_state *state)
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{
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int ret;
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ret = sps30_do_cmd(state, SPS30_RESET, NULL, 0);
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msleep(300);
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/*
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* Power-on-reset causes sensor to produce some glitch on i2c bus and
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* some controllers end up in error state. Recover simply by placing
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* some data on the bus, for example STOP_MEAS command, which
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* is NOP in this case.
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*/
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sps30_do_cmd(state, SPS30_STOP_MEAS, NULL, 0);
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state->state = RESET;
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return ret;
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}
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static ssize_t start_cleaning_store(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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@ -340,7 +198,7 @@ static ssize_t start_cleaning_store(struct device *dev,
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return -EINVAL;
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mutex_lock(&state->lock);
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ret = sps30_do_cmd(state, SPS30_START_FAN_CLEANING, NULL, 0);
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ret = state->ops->clean_fan(state);
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mutex_unlock(&state->lock);
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if (ret)
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return ret;
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@ -349,31 +207,29 @@ static ssize_t start_cleaning_store(struct device *dev,
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}
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static ssize_t cleaning_period_show(struct device *dev,
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struct device_attribute *attr,
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char *buf)
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struct device_attribute *attr,
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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 sps30_state *state = iio_priv(indio_dev);
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u8 tmp[4];
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__be32 val;
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int ret;
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mutex_lock(&state->lock);
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ret = sps30_do_cmd(state, SPS30_READ_AUTO_CLEANING_PERIOD, tmp, 4);
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ret = state->ops->read_cleaning_period(state, &val);
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mutex_unlock(&state->lock);
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if (ret)
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return ret;
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return sprintf(buf, "%d\n", get_unaligned_be32(tmp));
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return sprintf(buf, "%d\n", be32_to_cpu(val));
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}
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static ssize_t cleaning_period_store(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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static ssize_t cleaning_period_store(struct device *dev, 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 sps30_state *state = iio_priv(indio_dev);
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int val, ret;
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u8 tmp[4];
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if (kstrtoint(buf, 0, &val))
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return -EINVAL;
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@ -382,10 +238,8 @@ static ssize_t cleaning_period_store(struct device *dev,
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(val > SPS30_AUTO_CLEANING_PERIOD_MAX))
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return -EINVAL;
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put_unaligned_be32(val, tmp);
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mutex_lock(&state->lock);
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ret = sps30_do_cmd(state, SPS30_AUTO_CLEANING_PERIOD, tmp, 0);
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ret = state->ops->write_cleaning_period(state, cpu_to_be32(val));
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if (ret) {
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mutex_unlock(&state->lock);
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return ret;
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@ -397,7 +251,7 @@ static ssize_t cleaning_period_store(struct device *dev,
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* sensor requires reset in order to return up to date self cleaning
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* period
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*/
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ret = sps30_do_cmd_reset(state);
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ret = sps30_do_reset(state);
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if (ret)
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dev_warn(dev,
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"period changed but reads will return the old value\n");
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@ -460,90 +314,65 @@ static const struct iio_chan_spec sps30_channels[] = {
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IIO_CHAN_SOFT_TIMESTAMP(4),
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};
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static void sps30_stop_meas(void *data)
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static void sps30_devm_stop_meas(void *data)
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{
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struct sps30_state *state = data;
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sps30_do_cmd(state, SPS30_STOP_MEAS, NULL, 0);
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if (state->state == MEASURING)
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state->ops->stop_meas(state);
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}
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static const unsigned long sps30_scan_masks[] = { 0x0f, 0x00 };
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static int sps30_probe(struct i2c_client *client)
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int sps30_probe(struct device *dev, const char *name, void *priv, const struct sps30_ops *ops)
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{
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struct iio_dev *indio_dev;
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struct sps30_state *state;
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u8 buf[32];
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int ret;
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if (!i2c_check_functionality(client->adapter, I2C_FUNC_I2C))
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return -EOPNOTSUPP;
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indio_dev = devm_iio_device_alloc(&client->dev, sizeof(*state));
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indio_dev = devm_iio_device_alloc(dev, sizeof(*state));
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if (!indio_dev)
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return -ENOMEM;
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dev_set_drvdata(dev, indio_dev);
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state = iio_priv(indio_dev);
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i2c_set_clientdata(client, indio_dev);
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state->client = client;
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state->state = RESET;
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state->dev = dev;
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state->priv = priv;
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state->ops = ops;
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mutex_init(&state->lock);
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indio_dev->info = &sps30_info;
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indio_dev->name = client->name;
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indio_dev->name = name;
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indio_dev->channels = sps30_channels;
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indio_dev->num_channels = ARRAY_SIZE(sps30_channels);
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indio_dev->modes = INDIO_DIRECT_MODE;
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indio_dev->available_scan_masks = sps30_scan_masks;
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mutex_init(&state->lock);
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crc8_populate_msb(sps30_crc8_table, SPS30_CRC8_POLYNOMIAL);
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ret = sps30_do_cmd_reset(state);
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ret = sps30_do_reset(state);
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if (ret) {
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dev_err(&client->dev, "failed to reset device\n");
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dev_err(dev, "failed to reset device\n");
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return ret;
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}
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ret = sps30_do_cmd(state, SPS30_READ_SERIAL, buf, sizeof(buf));
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ret = state->ops->show_info(state);
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if (ret) {
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dev_err(&client->dev, "failed to read serial number\n");
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dev_err(dev, "failed to read device info\n");
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return ret;
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}
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/* returned serial number is already NUL terminated */
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dev_info(&client->dev, "serial number: %s\n", buf);
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ret = devm_add_action_or_reset(&client->dev, sps30_stop_meas, state);
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ret = devm_add_action_or_reset(dev, sps30_devm_stop_meas, state);
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if (ret)
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return ret;
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ret = devm_iio_triggered_buffer_setup(&client->dev, indio_dev, NULL,
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ret = devm_iio_triggered_buffer_setup(dev, indio_dev, NULL,
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sps30_trigger_handler, NULL);
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if (ret)
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return ret;
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return devm_iio_device_register(&client->dev, indio_dev);
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return devm_iio_device_register(dev, indio_dev);
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}
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static const struct i2c_device_id sps30_id[] = {
|
||||
{ "sps30" },
|
||||
{ }
|
||||
};
|
||||
MODULE_DEVICE_TABLE(i2c, sps30_id);
|
||||
|
||||
static const struct of_device_id sps30_of_match[] = {
|
||||
{ .compatible = "sensirion,sps30" },
|
||||
{ }
|
||||
};
|
||||
MODULE_DEVICE_TABLE(of, sps30_of_match);
|
||||
|
||||
static struct i2c_driver sps30_driver = {
|
||||
.driver = {
|
||||
.name = "sps30",
|
||||
.of_match_table = sps30_of_match,
|
||||
},
|
||||
.id_table = sps30_id,
|
||||
.probe_new = sps30_probe,
|
||||
};
|
||||
module_i2c_driver(sps30_driver);
|
||||
EXPORT_SYMBOL_GPL(sps30_probe);
|
||||
|
||||
MODULE_AUTHOR("Tomasz Duszynski <tduszyns@gmail.com>");
|
||||
MODULE_DESCRIPTION("Sensirion SPS30 particulate matter sensor driver");
|
||||
|
35
drivers/iio/chemical/sps30.h
Normal file
35
drivers/iio/chemical/sps30.h
Normal file
@ -0,0 +1,35 @@
|
||||
/* SPDX-License-Identifier: GPL-2.0 */
|
||||
#ifndef _SPS30_H
|
||||
#define _SPS30_H
|
||||
|
||||
#include <linux/types.h>
|
||||
|
||||
struct sps30_state;
|
||||
struct sps30_ops {
|
||||
int (*start_meas)(struct sps30_state *state);
|
||||
int (*stop_meas)(struct sps30_state *state);
|
||||
int (*read_meas)(struct sps30_state *state, __be32 *meas, size_t num);
|
||||
int (*reset)(struct sps30_state *state);
|
||||
int (*clean_fan)(struct sps30_state *state);
|
||||
int (*read_cleaning_period)(struct sps30_state *state, __be32 *period);
|
||||
int (*write_cleaning_period)(struct sps30_state *state, __be32 period);
|
||||
int (*show_info)(struct sps30_state *state);
|
||||
};
|
||||
|
||||
struct sps30_state {
|
||||
/* serialize access to the device */
|
||||
struct mutex lock;
|
||||
struct device *dev;
|
||||
int state;
|
||||
/*
|
||||
* priv pointer is solely for serdev driver private data. We keep it
|
||||
* here because driver_data inside dev has been already used for iio and
|
||||
* struct serdev_device doesn't have one.
|
||||
*/
|
||||
void *priv;
|
||||
const struct sps30_ops *ops;
|
||||
};
|
||||
|
||||
int sps30_probe(struct device *dev, const char *name, void *priv, const struct sps30_ops *ops);
|
||||
|
||||
#endif
|
258
drivers/iio/chemical/sps30_i2c.c
Normal file
258
drivers/iio/chemical/sps30_i2c.c
Normal file
@ -0,0 +1,258 @@
|
||||
// SPDX-License-Identifier: GPL-2.0
|
||||
/*
|
||||
* Sensirion SPS30 particulate matter sensor i2c driver
|
||||
*
|
||||
* Copyright (c) 2020 Tomasz Duszynski <tomasz.duszynski@octakon.com>
|
||||
*
|
||||
* I2C slave address: 0x69
|
||||
*/
|
||||
#include <asm/unaligned.h>
|
||||
#include <linux/crc8.h>
|
||||
#include <linux/delay.h>
|
||||
#include <linux/device.h>
|
||||
#include <linux/errno.h>
|
||||
#include <linux/i2c.h>
|
||||
#include <linux/mod_devicetable.h>
|
||||
#include <linux/module.h>
|
||||
#include <linux/types.h>
|
||||
|
||||
#include "sps30.h"
|
||||
|
||||
#define SPS30_I2C_CRC8_POLYNOMIAL 0x31
|
||||
/* max number of bytes needed to store PM measurements or serial string */
|
||||
#define SPS30_I2C_MAX_BUF_SIZE 48
|
||||
|
||||
DECLARE_CRC8_TABLE(sps30_i2c_crc8_table);
|
||||
|
||||
#define SPS30_I2C_START_MEAS 0x0010
|
||||
#define SPS30_I2C_STOP_MEAS 0x0104
|
||||
#define SPS30_I2C_READ_MEAS 0x0300
|
||||
#define SPS30_I2C_MEAS_READY 0x0202
|
||||
#define SPS30_I2C_RESET 0xd304
|
||||
#define SPS30_I2C_CLEAN_FAN 0x5607
|
||||
#define SPS30_I2C_PERIOD 0x8004
|
||||
#define SPS30_I2C_READ_SERIAL 0xd033
|
||||
#define SPS30_I2C_READ_VERSION 0xd100
|
||||
|
||||
static int sps30_i2c_xfer(struct sps30_state *state, unsigned char *txbuf, size_t txsize,
|
||||
unsigned char *rxbuf, size_t rxsize)
|
||||
{
|
||||
struct i2c_client *client = to_i2c_client(state->dev);
|
||||
int ret;
|
||||
|
||||
/*
|
||||
* Sensor does not support repeated start so instead of
|
||||
* sending two i2c messages in a row we just send one by one.
|
||||
*/
|
||||
ret = i2c_master_send(client, txbuf, txsize);
|
||||
if (ret < 0)
|
||||
return ret;
|
||||
if (ret != txsize)
|
||||
return -EIO;
|
||||
|
||||
if (!rxsize)
|
||||
return 0;
|
||||
|
||||
ret = i2c_master_recv(client, rxbuf, rxsize);
|
||||
if (ret < 0)
|
||||
return ret;
|
||||
if (ret != rxsize)
|
||||
return -EIO;
|
||||
|
||||
return 0;
|
||||
}
|
||||
|
||||
static int sps30_i2c_command(struct sps30_state *state, u16 cmd, void *arg, size_t arg_size,
|
||||
void *rsp, size_t rsp_size)
|
||||
{
|
||||
/*
|
||||
* Internally sensor stores measurements in a following manner:
|
||||
*
|
||||
* PM1: upper two bytes, crc8, lower two bytes, crc8
|
||||
* PM2P5: upper two bytes, crc8, lower two bytes, crc8
|
||||
* PM4: upper two bytes, crc8, lower two bytes, crc8
|
||||
* PM10: upper two bytes, crc8, lower two bytes, crc8
|
||||
*
|
||||
* What follows next are number concentration measurements and
|
||||
* typical particle size measurement which we omit.
|
||||
*/
|
||||
unsigned char buf[SPS30_I2C_MAX_BUF_SIZE];
|
||||
unsigned char *tmp;
|
||||
unsigned char crc;
|
||||
size_t i;
|
||||
int ret;
|
||||
|
||||
put_unaligned_be16(cmd, buf);
|
||||
i = 2;
|
||||
|
||||
if (rsp) {
|
||||
/* each two bytes are followed by a crc8 */
|
||||
rsp_size += rsp_size / 2;
|
||||
} else {
|
||||
tmp = arg;
|
||||
|
||||
while (arg_size) {
|
||||
buf[i] = *tmp++;
|
||||
buf[i + 1] = *tmp++;
|
||||
buf[i + 2] = crc8(sps30_i2c_crc8_table, buf + i, 2, CRC8_INIT_VALUE);
|
||||
arg_size -= 2;
|
||||
i += 3;
|
||||
}
|
||||
}
|
||||
|
||||
ret = sps30_i2c_xfer(state, buf, i, buf, rsp_size);
|
||||
if (ret)
|
||||
return ret;
|
||||
|
||||
/* validate received data and strip off crc bytes */
|
||||
tmp = rsp;
|
||||
for (i = 0; i < rsp_size; i += 3) {
|
||||
crc = crc8(sps30_i2c_crc8_table, buf + i, 2, CRC8_INIT_VALUE);
|
||||
if (crc != buf[i + 2]) {
|
||||
dev_err(state->dev, "data integrity check failed\n");
|
||||
return -EIO;
|
||||
}
|
||||
|
||||
*tmp++ = buf[i];
|
||||
*tmp++ = buf[i + 1];
|
||||
}
|
||||
|
||||
return 0;
|
||||
}
|
||||
|
||||
static int sps30_i2c_start_meas(struct sps30_state *state)
|
||||
{
|
||||
/* request BE IEEE754 formatted data */
|
||||
unsigned char buf[] = { 0x03, 0x00 };
|
||||
|
||||
return sps30_i2c_command(state, SPS30_I2C_START_MEAS, buf, sizeof(buf), NULL, 0);
|
||||
}
|
||||
|
||||
static int sps30_i2c_stop_meas(struct sps30_state *state)
|
||||
{
|
||||
return sps30_i2c_command(state, SPS30_I2C_STOP_MEAS, NULL, 0, NULL, 0);
|
||||
}
|
||||
|
||||
static int sps30_i2c_reset(struct sps30_state *state)
|
||||
{
|
||||
int ret;
|
||||
|
||||
ret = sps30_i2c_command(state, SPS30_I2C_RESET, NULL, 0, NULL, 0);
|
||||
msleep(500);
|
||||
/*
|
||||
* Power-on-reset causes sensor to produce some glitch on i2c bus and
|
||||
* some controllers end up in error state. Recover simply by placing
|
||||
* some data on the bus, for example STOP_MEAS command, which
|
||||
* is NOP in this case.
|
||||
*/
|
||||
sps30_i2c_stop_meas(state);
|
||||
|
||||
return ret;
|
||||
}
|
||||
|
||||
static bool sps30_i2c_meas_ready(struct sps30_state *state)
|
||||
{
|
||||
unsigned char buf[2];
|
||||
int ret;
|
||||
|
||||
ret = sps30_i2c_command(state, SPS30_I2C_MEAS_READY, NULL, 0, buf, sizeof(buf));
|
||||
if (ret)
|
||||
return false;
|
||||
|
||||
return buf[1];
|
||||
}
|
||||
|
||||
static int sps30_i2c_read_meas(struct sps30_state *state, __be32 *meas, size_t num)
|
||||
{
|
||||
/* measurements are ready within a second */
|
||||
if (msleep_interruptible(1000))
|
||||
return -EINTR;
|
||||
|
||||
if (!sps30_i2c_meas_ready(state))
|
||||
return -ETIMEDOUT;
|
||||
|
||||
return sps30_i2c_command(state, SPS30_I2C_READ_MEAS, NULL, 0, meas, sizeof(num) * num);
|
||||
}
|
||||
|
||||
static int sps30_i2c_clean_fan(struct sps30_state *state)
|
||||
{
|
||||
return sps30_i2c_command(state, SPS30_I2C_CLEAN_FAN, NULL, 0, NULL, 0);
|
||||
}
|
||||
|
||||
static int sps30_i2c_read_cleaning_period(struct sps30_state *state, __be32 *period)
|
||||
{
|
||||
return sps30_i2c_command(state, SPS30_I2C_PERIOD, NULL, 0, period, sizeof(*period));
|
||||
}
|
||||
|
||||
static int sps30_i2c_write_cleaning_period(struct sps30_state *state, __be32 period)
|
||||
{
|
||||
return sps30_i2c_command(state, SPS30_I2C_PERIOD, &period, sizeof(period), NULL, 0);
|
||||
}
|
||||
|
||||
static int sps30_i2c_show_info(struct sps30_state *state)
|
||||
{
|
||||
/* extra nul just in case */
|
||||
unsigned char buf[32 + 1] = { 0x00 };
|
||||
int ret;
|
||||
|
||||
ret = sps30_i2c_command(state, SPS30_I2C_READ_SERIAL, NULL, 0, buf, sizeof(buf) - 1);
|
||||
if (ret)
|
||||
return ret;
|
||||
|
||||
dev_info(state->dev, "serial number: %s\n", buf);
|
||||
|
||||
ret = sps30_i2c_command(state, SPS30_I2C_READ_VERSION, NULL, 0, buf, 2);
|
||||
if (ret)
|
||||
return ret;
|
||||
|
||||
dev_info(state->dev, "fw version: %u.%u\n", buf[0], buf[1]);
|
||||
|
||||
return 0;
|
||||
}
|
||||
|
||||
static const struct sps30_ops sps30_i2c_ops = {
|
||||
.start_meas = sps30_i2c_start_meas,
|
||||
.stop_meas = sps30_i2c_stop_meas,
|
||||
.read_meas = sps30_i2c_read_meas,
|
||||
.reset = sps30_i2c_reset,
|
||||
.clean_fan = sps30_i2c_clean_fan,
|
||||
.read_cleaning_period = sps30_i2c_read_cleaning_period,
|
||||
.write_cleaning_period = sps30_i2c_write_cleaning_period,
|
||||
.show_info = sps30_i2c_show_info,
|
||||
};
|
||||
|
||||
static int sps30_i2c_probe(struct i2c_client *client)
|
||||
{
|
||||
if (!i2c_check_functionality(client->adapter, I2C_FUNC_I2C))
|
||||
return -EOPNOTSUPP;
|
||||
|
||||
crc8_populate_msb(sps30_i2c_crc8_table, SPS30_I2C_CRC8_POLYNOMIAL);
|
||||
|
||||
return sps30_probe(&client->dev, client->name, NULL, &sps30_i2c_ops);
|
||||
}
|
||||
|
||||
static const struct i2c_device_id sps30_i2c_id[] = {
|
||||
{ "sps30" },
|
||||
{ }
|
||||
};
|
||||
MODULE_DEVICE_TABLE(i2c, sps30_i2c_id);
|
||||
|
||||
static const struct of_device_id sps30_i2c_of_match[] = {
|
||||
{ .compatible = "sensirion,sps30" },
|
||||
{ }
|
||||
};
|
||||
MODULE_DEVICE_TABLE(of, sps30_i2c_of_match);
|
||||
|
||||
static struct i2c_driver sps30_i2c_driver = {
|
||||
.driver = {
|
||||
.name = KBUILD_MODNAME,
|
||||
.of_match_table = sps30_i2c_of_match,
|
||||
},
|
||||
.id_table = sps30_i2c_id,
|
||||
.probe_new = sps30_i2c_probe,
|
||||
};
|
||||
module_i2c_driver(sps30_i2c_driver);
|
||||
|
||||
MODULE_AUTHOR("Tomasz Duszynski <tomasz.duszynski@octakon.com>");
|
||||
MODULE_DESCRIPTION("Sensirion SPS30 particulate matter sensor i2c driver");
|
||||
MODULE_LICENSE("GPL v2");
|
Loading…
Reference in New Issue
Block a user