| Message ID | 20210502134431.42647-2-tomasz.duszynski@octakon.com (mailing list archive) |
|---|---|
| State | New, archived |
| Headers | show |
| Series | iio: sps30: add support for serial interface | expand |
On Sun, 2 May 2021 15:44:29 +0200 Tomasz Duszynski <tomasz.duszynski@octakon.com> wrote: > 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> A comment way down the end. Basically says that dropping the i2c_device_id table is fine with me, but does occasionally cause problems as it's still used IIRC by greybus. Maybe someone will one day connect one of these to greybus :) Otherwise, looks good to me. Jonathan > --- > MAINTAINERS | 1 + > drivers/iio/chemical/Kconfig | 16 +- > drivers/iio/chemical/Makefile | 1 + > drivers/iio/chemical/sps30.c | 269 ++++++------------------------- > drivers/iio/chemical/sps30.h | 35 ++++ > drivers/iio/chemical/sps30_i2c.c | 251 ++++++++++++++++++++++++++++ > 6 files changed, 347 insertions(+), 226 deletions(-) > create mode 100644 drivers/iio/chemical/sps30.h > create mode 100644 drivers/iio/chemical/sps30_i2c.c > > diff --git a/MAINTAINERS b/MAINTAINERS > index ccc59fd7e5c0..4b39a9c48736 100644 > --- a/MAINTAINERS > +++ b/MAINTAINERS > @@ -16137,6 +16137,7 @@ 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> > diff --git a/drivers/iio/chemical/Kconfig b/drivers/iio/chemical/Kconfig > index 10bb431bc3ce..2b45a76ab7bc 100644 > --- a/drivers/iio/chemical/Kconfig > +++ b/drivers/iio/chemical/Kconfig > @@ -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" > diff --git a/drivers/iio/chemical/Makefile b/drivers/iio/chemical/Makefile > index fef63dd5bf92..41c264a229c0 100644 > --- a/drivers/iio/chemical/Makefile > +++ b/drivers/iio/chemical/Makefile > @@ -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 > diff --git a/drivers/iio/chemical/sps30.c b/drivers/iio/chemical/sps30.c > index 7486591588c3..d51314505115 100644 > --- a/drivers/iio/chemical/sps30.c > +++ b/drivers/iio/chemical/sps30.c > @@ -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); > - if (ret) > - return -EIO; > + ret = state->ops->read_meas(state, (__be32 *)data, size); > + if (ret) > + 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; > @@ -349,31 +207,29 @@ static ssize_t start_cleaning_store(struct device *dev, > } > > static ssize_t cleaning_period_show(struct device *dev, > - struct device_attribute *attr, > - char *buf) > + struct device_attribute *attr, > + char *buf) > { > 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, > - const char *buf, size_t len) > +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"); > diff --git a/drivers/iio/chemical/sps30.h b/drivers/iio/chemical/sps30.h > new file mode 100644 > index 000000000000..a58ee43cf45d > --- /dev/null > +++ b/drivers/iio/chemical/sps30.h > @@ -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 > diff --git a/drivers/iio/chemical/sps30_i2c.c b/drivers/iio/chemical/sps30_i2c.c > new file mode 100644 > index 000000000000..123ef23bf0eb > --- /dev/null > +++ b/drivers/iio/chemical/sps30_i2c.c > @@ -0,0 +1,251 @@ > +// 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 of_device_id sps30_i2c_of_match[] = { > + { .compatible = "sensirion,sps30" }, This drops the i2c_device_id table. I personally don't mind doing that, but it will cause trouble for anyone trying to use greybus or similar with this part (as IIRC they still rely on that id table). > + { } > +}; > +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, > + }, > + .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");
On Sun, May 02, 2021 at 06:32:20PM +0100, Jonathan Cameron wrote: > On Sun, 2 May 2021 15:44:29 +0200 > Tomasz Duszynski <tomasz.duszynski@octakon.com> wrote: > > > 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> > A comment way down the end. Basically says that dropping the i2c_device_id > table is fine with me, but does occasionally cause problems as it's still used > IIRC by greybus. Maybe someone will one day connect one of these to greybus :) > > Otherwise, looks good to me. > Good point. I'll leave it as is then just to make sure everything behaves as before. > > Jonathan > > > --- > > MAINTAINERS | 1 + > > drivers/iio/chemical/Kconfig | 16 +- > > drivers/iio/chemical/Makefile | 1 + > > drivers/iio/chemical/sps30.c | 269 ++++++------------------------- > > drivers/iio/chemical/sps30.h | 35 ++++ > > drivers/iio/chemical/sps30_i2c.c | 251 ++++++++++++++++++++++++++++ > > 6 files changed, 347 insertions(+), 226 deletions(-) > > create mode 100644 drivers/iio/chemical/sps30.h > > create mode 100644 drivers/iio/chemical/sps30_i2c.c > > > > diff --git a/MAINTAINERS b/MAINTAINERS > > index ccc59fd7e5c0..4b39a9c48736 100644 > > --- a/MAINTAINERS > > +++ b/MAINTAINERS > > @@ -16137,6 +16137,7 @@ 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> > > diff --git a/drivers/iio/chemical/Kconfig b/drivers/iio/chemical/Kconfig > > index 10bb431bc3ce..2b45a76ab7bc 100644 > > --- a/drivers/iio/chemical/Kconfig > > +++ b/drivers/iio/chemical/Kconfig > > @@ -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" > > diff --git a/drivers/iio/chemical/Makefile b/drivers/iio/chemical/Makefile > > index fef63dd5bf92..41c264a229c0 100644 > > --- a/drivers/iio/chemical/Makefile > > +++ b/drivers/iio/chemical/Makefile > > @@ -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 > > diff --git a/drivers/iio/chemical/sps30.c b/drivers/iio/chemical/sps30.c > > index 7486591588c3..d51314505115 100644 > > --- a/drivers/iio/chemical/sps30.c > > +++ b/drivers/iio/chemical/sps30.c > > @@ -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); > > - if (ret) > > - return -EIO; > > + ret = state->ops->read_meas(state, (__be32 *)data, size); > > + if (ret) > > + 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; > > @@ -349,31 +207,29 @@ static ssize_t start_cleaning_store(struct device *dev, > > } > > > > static ssize_t cleaning_period_show(struct device *dev, > > - struct device_attribute *attr, > > - char *buf) > > + struct device_attribute *attr, > > + char *buf) > > { > > 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, > > - const char *buf, size_t len) > > +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"); > > diff --git a/drivers/iio/chemical/sps30.h b/drivers/iio/chemical/sps30.h > > new file mode 100644 > > index 000000000000..a58ee43cf45d > > --- /dev/null > > +++ b/drivers/iio/chemical/sps30.h > > @@ -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 > > diff --git a/drivers/iio/chemical/sps30_i2c.c b/drivers/iio/chemical/sps30_i2c.c > > new file mode 100644 > > index 000000000000..123ef23bf0eb > > --- /dev/null > > +++ b/drivers/iio/chemical/sps30_i2c.c > > @@ -0,0 +1,251 @@ > > +// 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 of_device_id sps30_i2c_of_match[] = { > > + { .compatible = "sensirion,sps30" }, > > This drops the i2c_device_id table. I personally don't mind doing that, but > it will cause trouble for anyone trying to use greybus or similar with this part > (as IIRC they still rely on that id table). > > > + { } > > +}; > > +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, > > + }, > > + .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"); >
diff --git a/MAINTAINERS b/MAINTAINERS index ccc59fd7e5c0..4b39a9c48736 100644 --- a/MAINTAINERS +++ b/MAINTAINERS @@ -16137,6 +16137,7 @@ 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> diff --git a/drivers/iio/chemical/Kconfig b/drivers/iio/chemical/Kconfig index 10bb431bc3ce..2b45a76ab7bc 100644 --- a/drivers/iio/chemical/Kconfig +++ b/drivers/iio/chemical/Kconfig @@ -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" diff --git a/drivers/iio/chemical/Makefile b/drivers/iio/chemical/Makefile index fef63dd5bf92..41c264a229c0 100644 --- a/drivers/iio/chemical/Makefile +++ b/drivers/iio/chemical/Makefile @@ -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 diff --git a/drivers/iio/chemical/sps30.c b/drivers/iio/chemical/sps30.c index 7486591588c3..d51314505115 100644 --- a/drivers/iio/chemical/sps30.c +++ b/drivers/iio/chemical/sps30.c @@ -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); - if (ret) - return -EIO; + ret = state->ops->read_meas(state, (__be32 *)data, size); + if (ret) + 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; @@ -349,31 +207,29 @@ static ssize_t start_cleaning_store(struct device *dev, } static ssize_t cleaning_period_show(struct device *dev, - struct device_attribute *attr, - char *buf) + struct device_attribute *attr, + char *buf) { 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, - const char *buf, size_t len) +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"); diff --git a/drivers/iio/chemical/sps30.h b/drivers/iio/chemical/sps30.h new file mode 100644 index 000000000000..a58ee43cf45d --- /dev/null +++ b/drivers/iio/chemical/sps30.h @@ -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 diff --git a/drivers/iio/chemical/sps30_i2c.c b/drivers/iio/chemical/sps30_i2c.c new file mode 100644 index 000000000000..123ef23bf0eb --- /dev/null +++ b/drivers/iio/chemical/sps30_i2c.c @@ -0,0 +1,251 @@ +// 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 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, + }, + .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");
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> --- MAINTAINERS | 1 + drivers/iio/chemical/Kconfig | 16 +- drivers/iio/chemical/Makefile | 1 + drivers/iio/chemical/sps30.c | 269 ++++++------------------------- drivers/iio/chemical/sps30.h | 35 ++++ drivers/iio/chemical/sps30_i2c.c | 251 ++++++++++++++++++++++++++++ 6 files changed, 347 insertions(+), 226 deletions(-) create mode 100644 drivers/iio/chemical/sps30.h create mode 100644 drivers/iio/chemical/sps30_i2c.c