Honeywell mprls0025pa is a series of pressure sensors. Add initial I2C support. Note: - IIO buffered mode is supported - SPI mode is not supported Signed-off-by: Andreas Klinger <ak@xxxxxxxxxxxxx> --- drivers/iio/pressure/Kconfig | 13 + drivers/iio/pressure/Makefile | 1 + drivers/iio/pressure/mprls0025pa.c | 450 +++++++++++++++++++++++++++++ 3 files changed, 464 insertions(+) create mode 100644 drivers/iio/pressure/mprls0025pa.c diff --git a/drivers/iio/pressure/Kconfig b/drivers/iio/pressure/Kconfig index c9453389e4f7..43aef35ce778 100644 --- a/drivers/iio/pressure/Kconfig +++ b/drivers/iio/pressure/Kconfig @@ -148,6 +148,19 @@ config MPL3115 To compile this driver as a module, choose M here: the module will be called mpl3115. +config MPRLS0025PA + tristate "Honeywell MPRLS0025PA (MicroPressure sensors series)" + depends on I2C + select IIO_BUFFER + select IIO_TRIGGERED_BUFFER + help + Say Y here to build support for the Honeywell MicroPressure pressure + sensor series. There are many different types with different pressure + range. These ranges can be set up in the device tree. + + To compile this driver as a module, choose M here: the module will be + called mprls0025pa. + config MS5611 tristate "Measurement Specialties MS5611 pressure sensor driver" select IIO_BUFFER diff --git a/drivers/iio/pressure/Makefile b/drivers/iio/pressure/Makefile index 083ae87ff48f..c90f77210e94 100644 --- a/drivers/iio/pressure/Makefile +++ b/drivers/iio/pressure/Makefile @@ -19,6 +19,7 @@ obj-$(CONFIG_MPL115) += mpl115.o obj-$(CONFIG_MPL115_I2C) += mpl115_i2c.o obj-$(CONFIG_MPL115_SPI) += mpl115_spi.o obj-$(CONFIG_MPL3115) += mpl3115.o +obj-$(CONFIG_MPRLS0025PA) += mprls0025pa.o obj-$(CONFIG_MS5611) += ms5611_core.o obj-$(CONFIG_MS5611_I2C) += ms5611_i2c.o obj-$(CONFIG_MS5611_SPI) += ms5611_spi.o diff --git a/drivers/iio/pressure/mprls0025pa.c b/drivers/iio/pressure/mprls0025pa.c new file mode 100644 index 000000000000..06f40e47c68e --- /dev/null +++ b/drivers/iio/pressure/mprls0025pa.c @@ -0,0 +1,450 @@ +// SPDX-License-Identifier: GPL-2.0-or-later +/* + * MPRLS0025PA - Honeywell MicroPressure pressure sensor series driver + * + * Copyright (c) Andreas Klinger <ak@xxxxxxxxxxxxx> + * + * Data sheet: + * https://prod-edam.honeywell.com/content/dam/honeywell-edam/sps/siot/en-us/ + * products/sensors/pressure-sensors/board-mount-pressure-sensors/ + * micropressure-mpr-series/documents/ + * sps-siot-mpr-series-datasheet-32332628-ciid-172626.pdf + * + * 7-bit I2C default slave address: 0x18 + */ + +#include <linux/delay.h> +#include <linux/device.h> +#include <linux/i2c.h> +#include <linux/math64.h> +#include <linux/mod_devicetable.h> +#include <linux/module.h> +#include <linux/property.h> +#include <linux/units.h> + +#include <linux/gpio/consumer.h> + +#include <linux/iio/buffer.h> +#include <linux/iio/iio.h> +#include <linux/iio/trigger_consumer.h> +#include <linux/iio/triggered_buffer.h> + +#include <linux/regulator/consumer.h> + +#include <asm/unaligned.h> + +/* bits in i2c status byte */ +#define MPR_I2C_POWER BIT(6) /* device is powered */ +#define MPR_I2C_BUSY BIT(5) /* device is busy */ +#define MPR_I2C_MEMORY BIT(2) /* integrity test passed */ +#define MPR_I2C_MATH BIT(0) /* internal math saturation */ + +/* + * support _RAW sysfs interface: + * + * Calculation formula from the datasheet: + * pressure = (press_cnt - outputmin) * scale + pmin + * with: + * * pressure - measured pressure in Pascal + * * press_cnt - raw value read from sensor + * * pmin - minimum pressure range value of sensor (data->pmin) + * * pmax - maximum pressure range value of sensor (data->pmax) + * * outputmin - minimum numerical range raw value delivered by sensor + * (mpr_func_spec.output_min) + * * outputmax - maximum numerical range raw value delivered by sensor + * (mpr_func_spec.output_max) + * * scale - (pmax - pmin) / (outputmax - outputmin) + * + * formula of the userspace: + * pressure = (raw + offset) * scale + * + * Values given to the userspace in sysfs interface: + * * raw - press_cnt + * * offset - (-1 * outputmin) - pmin / scale + * note: With all sensors from the datasheet pmin = 0 + * which reduces the offset to (-1 * outputmin) + */ + +/* + * transfer function A: 10% to 90% of 2^24 + * transfer function B: 2.5% to 22.5% of 2^24 + * transfer function C: 20% to 80% of 2^24 + */ +enum mpr_func_id { + MPR_FUNCTION_A, + MPR_FUNCTION_B, + MPR_FUNCTION_C, +}; + +struct mpr_func_spec { + u32 output_min; + u32 output_max; +}; + +static const struct mpr_func_spec mpr_func_spec[] = { + [MPR_FUNCTION_A] = {.output_min = 1677722, .output_max = 15099494}, + [MPR_FUNCTION_B] = {.output_min = 419430, .output_max = 3774874}, + [MPR_FUNCTION_C] = {.output_min = 3355443, .output_max = 13421773}, +}; + +struct mpr_chan { + s32 pres; /* pressure value */ + s64 ts; /* timestamp */ +}; + +struct mpr_data { + struct i2c_client *client; + struct mutex lock; /* + * access to device during read + */ + u32 pmin; /* minimal pressure in pascal */ + u32 pmax; /* maximal pressure in pascal */ + enum mpr_func_id function; /* transfer function */ + u32 outmin; /* + * minimal numerical range raw + * value from sensor + */ + u32 outmax; /* + * maximal numerical range raw + * value from sensor + */ + int scale; /* int part of scale */ + int scale2; /* nano part of scale */ + int offset; /* int part of offset */ + int offset2; /* nano part of offset */ + struct gpio_desc *gpiod_reset; /* reset */ + int irq; /* + * end of conversion irq; + * used to distinguish between + * irq mode and reading in a + * loop until data is ready + */ + struct completion completion; /* handshake from irq to read */ + struct mpr_chan chan; /* + * channel values for buffered + * mode + */ +}; + +static const struct iio_chan_spec mpr_channels[] = { + { + .type = IIO_PRESSURE, + .info_mask_separate = BIT(IIO_CHAN_INFO_RAW) | + BIT(IIO_CHAN_INFO_SCALE) | + BIT(IIO_CHAN_INFO_OFFSET), + .scan_index = 0, + .scan_type = { + .sign = 's', + .realbits = 32, + .storagebits = 32, + .endianness = IIO_CPU, + }, + }, + IIO_CHAN_SOFT_TIMESTAMP(1), +}; + +static void mpr_reset(struct mpr_data *data) +{ + if (data->gpiod_reset) { + gpiod_set_value(data->gpiod_reset, 0); + udelay(10); + gpiod_set_value(data->gpiod_reset, 1); + } +} + +/** + * mpr_read_pressure() - Read pressure value from sensor via I2C + * @data: Pointer to private data struct. + * @press: Output value read from sensor. + * + * Reading from the sensor by sending and receiving I2C telegrams. + * + * If there is an end of conversion (EOC) interrupt registered the function + * waits for a maximum of one second for the interrupt. + * + * Context: The function can sleep and data->lock should be held when calling it + * Return: + * * 0 - OK, the pressure value could be read + * * -ETIMEDOUT - Timeout while waiting for the EOC interrupt or busy flag is + * still set after nloops attempts of reading + */ +static int mpr_read_pressure(struct mpr_data *data, s32 *press) +{ + struct device *dev = &data->client->dev; + int ret, i; + u8 wdata[] = {0xAA, 0x00, 0x00}; + s32 status; + int nloops = 10; + u8 buf[4]; + + reinit_completion(&data->completion); + + ret = i2c_master_send(data->client, wdata, sizeof(wdata)); + if (ret < 0) { + dev_err(dev, "error while writing ret: %d\n", ret); + return ret; + } + if (ret != sizeof(wdata)) { + dev_err(dev, "received size doesn't fit - ret: %d / %u\n", ret, + (u32)sizeof(wdata)); + return -EIO; + } + + if (data->irq > 0) { + ret = wait_for_completion_timeout(&data->completion, HZ); + if (!ret) { + dev_err(dev, "timeout while waiting for eoc irq\n"); + return -ETIMEDOUT; + } + } else { + /* wait until status indicates data is ready */ + for (i = 0; i < nloops; i++) { + /* + * datasheet only says to wait at least 5 ms for the + * data but leave the maximum response time open + * --> let's try it nloops (10) times which seems to be + * quite long + */ + usleep_range(5000, 10000); + status = i2c_smbus_read_byte(data->client); + if (status < 0) { + dev_err(dev, + "error while reading, status: %d\n", + status); + return status; + } + if (!(status & MPR_I2C_BUSY)) + break; + } + if (i == nloops) { + dev_err(dev, "timeout while reading\n"); + return -ETIMEDOUT; + } + } + + ret = i2c_master_recv(data->client, buf, sizeof(buf)); + if (ret < 0) { + dev_err(dev, "error in i2c_master_recv ret: %d\n", ret); + return ret; + } + if (ret != sizeof(buf)) { + dev_err(dev, "received size doesn't fit - ret: %d / %u\n", ret, + (u32)sizeof(buf)); + return -EIO; + } + + if (buf[0] & MPR_I2C_BUSY) { + /* + * it should never be the case that status still indicates + * business + */ + dev_err(dev, "data still not ready: %08x\n", buf[0]); + return -ETIMEDOUT; + } + + *press = get_unaligned_be24(&buf[1]); + + dev_dbg(dev, "received: %*ph cnt: %d\n", ret, buf, *press); + + return 0; +} + +static irqreturn_t mpr_eoc_handler(int irq, void *p) +{ + struct mpr_data *data = p; + + complete(&data->completion); + + return IRQ_HANDLED; +} + +static irqreturn_t mpr_trigger_handler(int irq, void *p) +{ + int ret; + struct iio_poll_func *pf = p; + struct iio_dev *indio_dev = pf->indio_dev; + struct mpr_data *data = iio_priv(indio_dev); + + mutex_lock(&data->lock); + ret = mpr_read_pressure(data, &data->chan.pres); + if (ret < 0) + goto err; + + iio_push_to_buffers_with_timestamp(indio_dev, &data->chan, + iio_get_time_ns(indio_dev)); + +err: + mutex_unlock(&data->lock); + iio_trigger_notify_done(indio_dev->trig); + + return IRQ_HANDLED; +} + +static int mpr_read_raw(struct iio_dev *indio_dev, + struct iio_chan_spec const *chan, int *val, int *val2, long mask) +{ + int ret; + s32 pressure; + struct mpr_data *data = iio_priv(indio_dev); + + if (chan->type != IIO_PRESSURE) + return -EINVAL; + + switch (mask) { + case IIO_CHAN_INFO_RAW: + mutex_lock(&data->lock); + ret = mpr_read_pressure(data, &pressure); + mutex_unlock(&data->lock); + if (ret < 0) + return ret; + *val = pressure; + return IIO_VAL_INT; + case IIO_CHAN_INFO_SCALE: + *val = data->scale; + *val2 = data->scale2; + return IIO_VAL_INT_PLUS_NANO; + case IIO_CHAN_INFO_OFFSET: + *val = data->offset; + *val2 = data->offset2; + return IIO_VAL_INT_PLUS_NANO; + default: + return -EINVAL; + } +} + +static const struct iio_info mpr_info = { + .read_raw = &mpr_read_raw, +}; + +static int mpr_probe(struct i2c_client *client) +{ + int ret; + struct mpr_data *data; + struct iio_dev *indio_dev; + struct device *dev = &client->dev; + s64 scale, offset; + + if (!i2c_check_functionality(client->adapter, I2C_FUNC_SMBUS_READ_BYTE)) + return dev_err_probe(dev, -EOPNOTSUPP, + "I2C functionality not supported\n"); + + indio_dev = devm_iio_device_alloc(dev, sizeof(*data)); + if (!indio_dev) + return dev_err_probe(dev, -ENOMEM, "couldn't get iio_dev\n"); + + data = iio_priv(indio_dev); + data->client = client; + data->irq = client->irq; + + mutex_init(&data->lock); + init_completion(&data->completion); + + indio_dev->name = "mprls0025pa"; + indio_dev->info = &mpr_info; + indio_dev->channels = mpr_channels; + indio_dev->num_channels = ARRAY_SIZE(mpr_channels); + indio_dev->modes = INDIO_DIRECT_MODE; + + ret = devm_regulator_get_enable(dev, "vdd"); + if (ret) + return dev_err_probe(dev, ret, + "can't get and enable vdd supply\n"); + + if (dev_fwnode(dev)) { + ret = device_property_read_u32(dev, "honeywell,pmin-pascal", + &data->pmin); + if (ret) + return dev_err_probe(dev, ret, + "honeywell,pmin-pascal could not be read\n"); + ret = device_property_read_u32(dev, "honeywell,pmax-pascal", + &data->pmax); + if (ret) + return dev_err_probe(dev, ret, + "honeywell,pmax-pascal could not be read\n"); + ret = device_property_read_u32(dev, + "honeywell,transfer-function", &data->function); + if (ret) + return dev_err_probe(dev, ret, + "honeywell,transfer-function could not be read\n"); + if (data->function > MPR_FUNCTION_C) + return dev_err_probe(dev, -EINVAL, + "honeywell,transfer-function %d invalid\n", + data->function); + } else { + /* when loaded as i2c device we need to use default values */ + dev_notice(dev, "firmware node not found; using defaults\n"); + data->pmin = 0; + data->pmax = 172369; /* 25 psi */ + data->function = MPR_FUNCTION_A; + } + + data->outmin = mpr_func_spec[data->function].output_min; + data->outmax = mpr_func_spec[data->function].output_max; + + /* use 64 bit calculation for preserving a reasonable precision */ + scale = div_s64(((s64)(data->pmax - data->pmin)) * NANO, + data->outmax - data->outmin); + data->scale = div_s64_rem(scale, NANO, &data->scale2); + /* + * multiply with NANO before dividing by scale and later divide by NANO + * again. + */ + offset = ((-1LL) * (s64)data->outmin) * NANO - + div_s64(div_s64((s64)data->pmin * NANO, scale), NANO); + data->offset = div_s64_rem(offset, NANO, &data->offset2); + + if (data->irq > 0) { + ret = devm_request_irq(dev, data->irq, mpr_eoc_handler, + IRQF_TRIGGER_RISING, client->name, data); + if (ret) + return dev_err_probe(dev, ret, + "request irq %d failed\n", data->irq); + } + + data->gpiod_reset = devm_gpiod_get_optional(dev, "reset", + GPIOD_OUT_HIGH); + if (IS_ERR(data->gpiod_reset)) + return dev_err_probe(dev, PTR_ERR(data->gpiod_reset), + "request reset-gpio failed\n"); + + mpr_reset(data); + + ret = devm_iio_triggered_buffer_setup(dev, indio_dev, NULL, + mpr_trigger_handler, NULL); + if (ret) + return dev_err_probe(dev, ret, + "iio triggered buffer setup failed\n"); + + ret = devm_iio_device_register(dev, indio_dev); + if (ret) + return dev_err_probe(dev, ret, + "unable to register iio device\n"); + + return 0; +} + +static const struct of_device_id mpr_matches[] = { + { .compatible = "honeywell,mprls0025pa" }, + { } +}; +MODULE_DEVICE_TABLE(of, mpr_matches); + +static const struct i2c_device_id mpr_id[] = { + { "mprls0025pa" }, + { } +}; +MODULE_DEVICE_TABLE(i2c, mpr_id); + +static struct i2c_driver mpr_driver = { + .probe_new = mpr_probe, + .id_table = mpr_id, + .driver = { + .name = "mprls0025pa", + .of_match_table = mpr_matches, + }, +}; +module_i2c_driver(mpr_driver); + +MODULE_AUTHOR("Andreas Klinger <ak@xxxxxxxxxxxxx>"); +MODULE_DESCRIPTION("Honeywell MPRLS0025PA I2C driver"); +MODULE_LICENSE("GPL"); -- 2.30.2
