Commit 8f3f1308 authored by Tomasz Duszynski's avatar Tomasz Duszynski Committed by Jonathan Cameron
Browse files

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: default avatarTomasz Duszynski <tomasz.duszynski@octakon.com>
Signed-off-by: default avatarJonathan Cameron <Jonathan.Cameron@huawei.com>
parent 101af4c2

MAINTAINERS

+1 −0
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@@ -16484,6 +16484,7 @@ M: Tomasz Duszynski <tduszyns@gmail.com> 
S:	Maintained

F:	Documentation/devicetree/bindings/iio/chemical/sensirion,sps30.yaml

F:	drivers/iio/chemical/sps30.c

F:	drivers/iio/chemical/sps30_i2c.c









SERIAL DEVICE BUS









M:	Rob Herring <robh@kernel.org>
































drivers/iio/chemical/Kconfig



+10
−6






























Original line number
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@@ -132,17 +132,21 @@ config SENSIRION_SGP30







	  module will be called sgp30.



















config SPS30









	tristate "SPS30 particulate matter sensor"









	depends on I2C









	select CRC8









	tristate









	select IIO_BUFFER









	select IIO_TRIGGERED_BUFFER



















config SPS30_I2C









	tristate "SPS30 particulate matter sensor I2C driver"









	depends on I2C









	select SPS30









	select CRC8









	help









	  Say Y here to build support for the Sensirion SPS30 particulate









	  matter sensor.









	  Say Y here to build support for the Sensirion SPS30 I2C interface









	  driver.



















	  To compile this driver as a module, choose M here: the module will









	  be called sps30.









	  be called sps30_i2c.



















config VZ89X









	tristate "SGX Sensortech MiCS VZ89X VOC sensor"
































drivers/iio/chemical/Makefile



+1
−0






























Original line number
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Diff line







@@ -17,4 +17,5 @@ obj-$(CONFIG_SCD30_I2C) += scd30_i2c.o







obj-$(CONFIG_SCD30_SERIAL) += scd30_serial.o









obj-$(CONFIG_SENSIRION_SGP30)	+= sgp30.o









obj-$(CONFIG_SPS30) += sps30.o









obj-$(CONFIG_SPS30_I2C) += sps30_i2c.o









obj-$(CONFIG_VZ89X)		+= vz89x.o
























drivers/iio/chemical/sps30.c



+49
−220






























Original line number
Diff line number
Diff line







@@ -3,11 +3,8 @@







 * Sensirion SPS30 particulate matter sensor driver









 *









 * Copyright (c) Tomasz Duszynski <tduszyns@gmail.com>









 *









 * I2C slave address: 0x69









 */



















#include <asm/unaligned.h>









#include <linux/crc8.h>









#include <linux/delay.h>









#include <linux/i2c.h>








@@ -19,27 +16,14 @@







#include <linux/kernel.h>









#include <linux/module.h>



















#define SPS30_CRC8_POLYNOMIAL 0x31









/* max number of bytes needed to store PM measurements or serial string */









#define SPS30_MAX_READ_SIZE 48









#include "sps30.h"



















/* sensor measures reliably up to 3000 ug / m3 */









#define SPS30_MAX_PM 3000









/* minimum and maximum self cleaning periods in seconds */









#define SPS30_AUTO_CLEANING_PERIOD_MIN 0









#define SPS30_AUTO_CLEANING_PERIOD_MAX 604800



















/* SPS30 commands */









#define SPS30_START_MEAS 0x0010









#define SPS30_STOP_MEAS 0x0104









#define SPS30_RESET 0xd304









#define SPS30_READ_DATA_READY_FLAG 0x0202









#define SPS30_READ_DATA 0x0300









#define SPS30_READ_SERIAL 0xd033









#define SPS30_START_FAN_CLEANING 0x5607









#define SPS30_AUTO_CLEANING_PERIOD 0x8004









/* not a sensor command per se, used only to distinguish write from read */









#define SPS30_READ_AUTO_CLEANING_PERIOD 0x8005



















enum {









	PM1,









	PM2P5,








@@ -52,114 +36,9 @@ enum {







	MEASURING,









};



















struct sps30_state {









	struct i2c_client *client;









	/*









	 * Guards against concurrent access to sensor registers.









	 * Must be held whenever sequence of commands is to be executed.









	 */









	struct mutex lock;









	int state;









};



















DECLARE_CRC8_TABLE(sps30_crc8_table);



















static int sps30_write_then_read(struct sps30_state *state, u8 *txbuf,









				 int txsize, u8 *rxbuf, int rxsize)









{









	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(state->client, txbuf, txsize);









	if (ret != txsize)









		return ret < 0 ? ret : -EIO;



















	if (!rxbuf)









		return 0;



















	ret = i2c_master_recv(state->client, rxbuf, rxsize);









	if (ret != rxsize)









		return ret < 0 ? ret : -EIO;



















	return 0;









}



















static int sps30_do_cmd(struct sps30_state *state, u16 cmd, u8 *data, int 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.









	 */









	u8 buf[SPS30_MAX_READ_SIZE] = { cmd >> 8, cmd };









	int i, ret = 0;



















	switch (cmd) {









	case SPS30_START_MEAS:









		buf[2] = 0x03;









		buf[3] = 0x00;









		buf[4] = crc8(sps30_crc8_table, &buf[2], 2, CRC8_INIT_VALUE);









		ret = sps30_write_then_read(state, buf, 5, NULL, 0);









		break;









	case SPS30_STOP_MEAS:









	case SPS30_RESET:









	case SPS30_START_FAN_CLEANING:









		ret = sps30_write_then_read(state, buf, 2, NULL, 0);









		break;









	case SPS30_READ_AUTO_CLEANING_PERIOD:









		buf[0] = SPS30_AUTO_CLEANING_PERIOD >> 8;









		buf[1] = (u8)(SPS30_AUTO_CLEANING_PERIOD & 0xff);









		fallthrough;









	case SPS30_READ_DATA_READY_FLAG:









	case SPS30_READ_DATA:









	case SPS30_READ_SERIAL:









		/* every two data bytes are checksummed */









		size += size / 2;









		ret = sps30_write_then_read(state, buf, 2, buf, size);









		break;









	case SPS30_AUTO_CLEANING_PERIOD:









		buf[2] = data[0];









		buf[3] = data[1];









		buf[4] = crc8(sps30_crc8_table, &buf[2], 2, CRC8_INIT_VALUE);









		buf[5] = data[2];









		buf[6] = data[3];









		buf[7] = crc8(sps30_crc8_table, &buf[5], 2, CRC8_INIT_VALUE);









		ret = sps30_write_then_read(state, buf, 8, NULL, 0);









		break;









	}



















	if (ret)









		return ret;



















	/* validate received data and strip off crc bytes */









	for (i = 0; i < size; i += 3) {









		u8 crc = crc8(sps30_crc8_table, &buf[i], 2, CRC8_INIT_VALUE);



















		if (crc != buf[i + 2]) {









			dev_err(&state->client->dev,









				"data integrity check failed\n");









			return -EIO;









		}



















		*data++ = buf[i];









		*data++ = buf[i + 1];









	}



















	return 0;









}



















static s32 sps30_float_to_int_clamped(const u8 *fp)









static s32 sps30_float_to_int_clamped(__be32 *fp)









{









	int val = get_unaligned_be32(fp);









	int val = be32_to_cpup(fp);









	int mantissa = val & GENMASK(22, 0);









	/* this is fine since passed float is always non-negative */









	int exp = val >> 23;








@@ -188,38 +67,35 @@ static s32 sps30_float_to_int_clamped(const u8 *fp)

















static int sps30_do_meas(struct sps30_state *state, s32 *data, int size)









{









	int i, ret, tries = 5;









	u8 tmp[16];









	int i, ret;



















	if (state->state == RESET) {









		ret = sps30_do_cmd(state, SPS30_START_MEAS, NULL, 0);









		ret = state->ops->start_meas(state);









		if (ret)









			return ret;



















		state->state = MEASURING;









	}



















	while (tries--) {









		ret = sps30_do_cmd(state, SPS30_READ_DATA_READY_FLAG, tmp, 2);









	ret = state->ops->read_meas(state, (__be32 *)data, size);









	if (ret)









			return -EIO;









		return ret;



















		/* new measurements ready to be read */









		if (tmp[1] == 1)









			break;









	for (i = 0; i < size; i++)









		data[i] = sps30_float_to_int_clamped((__be32 *)&data[i]);



















		msleep_interruptible(300);









	return 0;









}



















	if (tries == -1)









		return -ETIMEDOUT;









static int sps30_do_reset(struct sps30_state *state)









{









	int ret;



















	ret = sps30_do_cmd(state, SPS30_READ_DATA, tmp, sizeof(int) * size);









	ret = state->ops->reset(state);









	if (ret)









		return ret;



















	for (i = 0; i < size; i++)









		data[i] = sps30_float_to_int_clamped(&tmp[4 * i]);









	state->state = RESET;



















	return 0;









}








@@ -310,24 +186,6 @@ static int sps30_read_raw(struct iio_dev *indio_dev,







	return -EINVAL;









}



















static int sps30_do_cmd_reset(struct sps30_state *state)









{









	int ret;



















	ret = sps30_do_cmd(state, SPS30_RESET, NULL, 0);









	msleep(300);









	/*









	 * 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_do_cmd(state, SPS30_STOP_MEAS, NULL, 0);









	state->state = RESET;



















	return ret;









}



















static ssize_t start_cleaning_store(struct device *dev,









				    struct device_attribute *attr,









				    const char *buf, size_t len)








@@ -340,7 +198,7 @@ static ssize_t start_cleaning_store(struct device *dev,







		return -EINVAL;



















	mutex_lock(&state->lock);









	ret = sps30_do_cmd(state, SPS30_START_FAN_CLEANING, NULL, 0);









	ret = state->ops->clean_fan(state);









	mutex_unlock(&state->lock);









	if (ret)









		return ret;








@@ -354,26 +212,24 @@ static ssize_t cleaning_period_show(struct device *dev,







{









	struct iio_dev *indio_dev = dev_to_iio_dev(dev);









	struct sps30_state *state = iio_priv(indio_dev);









	u8 tmp[4];









	__be32 val;









	int ret;



















	mutex_lock(&state->lock);









	ret = sps30_do_cmd(state, SPS30_READ_AUTO_CLEANING_PERIOD, tmp, 4);









	ret = state->ops->read_cleaning_period(state, &val);









	mutex_unlock(&state->lock);









	if (ret)









		return ret;



















	return sprintf(buf, "%d\n", get_unaligned_be32(tmp));









	return sprintf(buf, "%d\n", be32_to_cpu(val));









}



















static ssize_t cleaning_period_store(struct device *dev,









				       struct device_attribute *attr,









static ssize_t cleaning_period_store(struct device *dev, struct device_attribute *attr,









				     const char *buf, size_t len)









{









	struct iio_dev *indio_dev = dev_to_iio_dev(dev);









	struct sps30_state *state = iio_priv(indio_dev);









	int val, ret;









	u8 tmp[4];



















	if (kstrtoint(buf, 0, &val))









		return -EINVAL;








@@ -382,10 +238,8 @@ static ssize_t cleaning_period_store(struct device *dev,







	    (val > SPS30_AUTO_CLEANING_PERIOD_MAX))









		return -EINVAL;



















	put_unaligned_be32(val, tmp);



















	mutex_lock(&state->lock);









	ret = sps30_do_cmd(state, SPS30_AUTO_CLEANING_PERIOD, tmp, 0);









	ret = state->ops->write_cleaning_period(state, cpu_to_be32(val));









	if (ret) {









		mutex_unlock(&state->lock);









		return ret;








@@ -397,7 +251,7 @@ static ssize_t cleaning_period_store(struct device *dev,







	 * sensor requires reset in order to return up to date self cleaning









	 * period









	 */









	ret = sps30_do_cmd_reset(state);









	ret = sps30_do_reset(state);









	if (ret)









		dev_warn(dev,









			 "period changed but reads will return the old value\n");








@@ -460,90 +314,65 @@ static const struct iio_chan_spec sps30_channels[] = {







	IIO_CHAN_SOFT_TIMESTAMP(4),









};



















static void sps30_stop_meas(void *data)









static void sps30_devm_stop_meas(void *data)









{









	struct sps30_state *state = data;



















	sps30_do_cmd(state, SPS30_STOP_MEAS, NULL, 0);









	if (state->state == MEASURING)









		state->ops->stop_meas(state);









}



















static const unsigned long sps30_scan_masks[] = { 0x0f, 0x00 };



















static int sps30_probe(struct i2c_client *client)









int sps30_probe(struct device *dev, const char *name, void *priv, const struct sps30_ops *ops)









{









	struct iio_dev *indio_dev;









	struct sps30_state *state;









	u8 buf[32];









	int ret;



















	if (!i2c_check_functionality(client->adapter, I2C_FUNC_I2C))









		return -EOPNOTSUPP;



















	indio_dev = devm_iio_device_alloc(&client->dev, sizeof(*state));









	indio_dev = devm_iio_device_alloc(dev, sizeof(*state));









	if (!indio_dev)









		return -ENOMEM;



















	dev_set_drvdata(dev, indio_dev);



















	state = iio_priv(indio_dev);









	i2c_set_clientdata(client, indio_dev);









	state->client = client;









	state->state = RESET;









	state->dev = dev;









	state->priv = priv;









	state->ops = ops;









	mutex_init(&state->lock);



















	indio_dev->info = &sps30_info;









	indio_dev->name = client->name;









	indio_dev->name = name;









	indio_dev->channels = sps30_channels;









	indio_dev->num_channels = ARRAY_SIZE(sps30_channels);









	indio_dev->modes = INDIO_DIRECT_MODE;









	indio_dev->available_scan_masks = sps30_scan_masks;



















	mutex_init(&state->lock);









	crc8_populate_msb(sps30_crc8_table, SPS30_CRC8_POLYNOMIAL);



















	ret = sps30_do_cmd_reset(state);









	ret = sps30_do_reset(state);









	if (ret) {









		dev_err(&client->dev, "failed to reset device\n");









		dev_err(dev, "failed to reset device\n");









		return ret;









	}



















	ret = sps30_do_cmd(state, SPS30_READ_SERIAL, buf, sizeof(buf));









	ret = state->ops->show_info(state);









	if (ret) {









		dev_err(&client->dev, "failed to read serial number\n");









		dev_err(dev, "failed to read device info\n");









		return ret;









	}









	/* returned serial number is already NUL terminated */









	dev_info(&client->dev, "serial number: %s\n", buf);



















	ret = devm_add_action_or_reset(&client->dev, sps30_stop_meas, state);









	ret = devm_add_action_or_reset(dev, sps30_devm_stop_meas, state);









	if (ret)









		return ret;



















	ret = devm_iio_triggered_buffer_setup(&client->dev, indio_dev, NULL,









	ret = devm_iio_triggered_buffer_setup(dev, indio_dev, NULL,









					      sps30_trigger_handler, NULL);









	if (ret)









		return ret;



















	return devm_iio_device_register(&client->dev, indio_dev);









	return devm_iio_device_register(dev, indio_dev);









}



















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");
































drivers/iio/chemical/sps30.h
0 → 100644



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/* 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