diff options
Diffstat (limited to 'drivers/iio')
-rw-r--r-- | drivers/iio/magnetometer/Kconfig | 13 | ||||
-rw-r--r-- | drivers/iio/magnetometer/Makefile | 1 | ||||
-rw-r--r-- | drivers/iio/magnetometer/als31300.c | 494 |
3 files changed, 508 insertions, 0 deletions
diff --git a/drivers/iio/magnetometer/Kconfig b/drivers/iio/magnetometer/Kconfig index f69ac75500f9..7177cd1d67cb 100644 --- a/drivers/iio/magnetometer/Kconfig +++ b/drivers/iio/magnetometer/Kconfig @@ -54,6 +54,19 @@ config AK09911 help Deprecated: AK09911 is now supported by AK8975 driver. +config ALS31300 + tristate "Allegro MicroSystems ALS31300 3-D Linear Hall Effect Sensor" + depends on I2C + select REGMAP_I2C + select IIO_BUFFER + select IIO_TRIGGERED_BUFFER + help + Say yes here to build support for the Allegro MicroSystems + ALS31300 Hall Effect Sensor through its I2C interface. + + To compile this driver as a module, choose M here: the + module will be called als31300. + config BMC150_MAGN tristate select IIO_BUFFER diff --git a/drivers/iio/magnetometer/Makefile b/drivers/iio/magnetometer/Makefile index ec5c46fbf999..3e4c2ecd9adf 100644 --- a/drivers/iio/magnetometer/Makefile +++ b/drivers/iio/magnetometer/Makefile @@ -7,6 +7,7 @@ obj-$(CONFIG_AF8133J) += af8133j.o obj-$(CONFIG_AK8974) += ak8974.o obj-$(CONFIG_AK8975) += ak8975.o +obj-$(CONFIG_ALS31300) += als31300.o obj-$(CONFIG_BMC150_MAGN) += bmc150_magn.o obj-$(CONFIG_BMC150_MAGN_I2C) += bmc150_magn_i2c.o obj-$(CONFIG_BMC150_MAGN_SPI) += bmc150_magn_spi.o diff --git a/drivers/iio/magnetometer/als31300.c b/drivers/iio/magnetometer/als31300.c new file mode 100644 index 000000000000..87b60c4e81fa --- /dev/null +++ b/drivers/iio/magnetometer/als31300.c @@ -0,0 +1,494 @@ +// SPDX-License-Identifier: GPL-2.0-only +/* + * Driver for the Allegro MicroSystems ALS31300 3-D Linear Hall Effect Sensor + * + * Copyright (c) 2024 Linaro Limited + */ + +#include <linux/bits.h> +#include <linux/bitfield.h> +#include <linux/delay.h> +#include <linux/module.h> +#include <linux/i2c.h> +#include <linux/regmap.h> +#include <linux/pm.h> +#include <linux/pm_runtime.h> +#include <linux/regulator/consumer.h> +#include <linux/types.h> +#include <linux/units.h> + +#include <linux/iio/buffer.h> +#include <linux/iio/iio.h> +#include <linux/iio/trigger_consumer.h> +#include <linux/iio/triggered_buffer.h> + +/* + * The Allegro MicroSystems ALS31300 has an EEPROM space to configure how + * the device works and how the interrupt line behaves. + * Only the default setup with external trigger is supported. + * + * While the bindings supports declaring an interrupt line, those + * events are not supported. + * + * It should be possible to adapt the driver to the current + * device EEPROM setup at runtime. + */ + +#define ALS31300_EEPROM_CONFIG 0x02 +#define ALS31300_EEPROM_INTERRUPT 0x03 +#define ALS31300_EEPROM_CUSTOMER_1 0x0d +#define ALS31300_EEPROM_CUSTOMER_2 0x0e +#define ALS31300_EEPROM_CUSTOMER_3 0x0f +#define ALS31300_VOL_MODE 0x27 +#define ALS31300_VOL_MODE_LPDCM GENMASK(6, 4) +#define ALS31300_LPDCM_INACTIVE_0_5_MS 0 +#define ALS31300_LPDCM_INACTIVE_1_0_MS 1 +#define ALS31300_LPDCM_INACTIVE_5_0_MS 2 +#define ALS31300_LPDCM_INACTIVE_10_0_MS 3 +#define ALS31300_LPDCM_INACTIVE_50_0_MS 4 +#define ALS31300_LPDCM_INACTIVE_100_0_MS 5 +#define ALS31300_LPDCM_INACTIVE_500_0_MS 6 +#define ALS31300_LPDCM_INACTIVE_1000_0_MS 7 +#define ALS31300_VOL_MODE_SLEEP GENMASK(1, 0) +#define ALS31300_VOL_MODE_ACTIVE_MODE 0 +#define ALS31300_VOL_MODE_SLEEP_MODE 1 +#define ALS31300_VOL_MODE_LPDCM_MODE 2 +#define ALS31300_VOL_MSB 0x28 +#define ALS31300_VOL_MSB_TEMPERATURE GENMASK(5, 0) +#define ALS31300_VOL_MSB_INTERRUPT BIT(6) +#define ALS31300_VOL_MSB_NEW_DATA BIT(7) +#define ALS31300_VOL_MSB_Z_AXIS GENMASK(15, 8) +#define ALS31300_VOL_MSB_Y_AXIS GENMASK(23, 16) +#define ALS31300_VOL_MSB_X_AXIS GENMASK(31, 24) +#define ALS31300_VOL_LSB 0x29 +#define ALS31300_VOL_LSB_TEMPERATURE GENMASK(5, 0) +#define ALS31300_VOL_LSB_HALL_STATUS GENMASK(7, 7) +#define ALS31300_VOL_LSB_Z_AXIS GENMASK(11, 8) +#define ALS31300_VOL_LSB_Y_AXIS GENMASK(15, 12) +#define ALS31300_VOL_LSB_X_AXIS GENMASK(19, 16) +#define ALS31300_VOL_LSB_INTERRUPT_WRITE BIT(20) +#define ALS31300_CUSTOMER_ACCESS 0x35 + +#define ALS31300_DATA_X_GET(b) \ + sign_extend32(FIELD_GET(ALS31300_VOL_MSB_X_AXIS, b[0]) << 4 | \ + FIELD_GET(ALS31300_VOL_LSB_X_AXIS, b[1]), 11) +#define ALS31300_DATA_Y_GET(b) \ + sign_extend32(FIELD_GET(ALS31300_VOL_MSB_Y_AXIS, b[0]) << 4 | \ + FIELD_GET(ALS31300_VOL_LSB_Y_AXIS, b[1]), 11) +#define ALS31300_DATA_Z_GET(b) \ + sign_extend32(FIELD_GET(ALS31300_VOL_MSB_Z_AXIS, b[0]) << 4 | \ + FIELD_GET(ALS31300_VOL_LSB_Z_AXIS, b[1]), 11) +#define ALS31300_TEMPERATURE_GET(b) \ + (FIELD_GET(ALS31300_VOL_MSB_TEMPERATURE, b[0]) << 6 | \ + FIELD_GET(ALS31300_VOL_LSB_TEMPERATURE, b[1])) + +enum als31300_channels { + TEMPERATURE = 0, + AXIS_X, + AXIS_Y, + AXIS_Z, +}; + +struct als31300_variant_info { + u8 sensitivity; +}; + +struct als31300_data { + struct device *dev; + /* protects power on/off the device and access HW */ + struct mutex mutex; + const struct als31300_variant_info *variant_info; + struct regmap *map; +}; + +/* The whole measure is split into 2x32-bit registers, we need to read them both at once */ +static int als31300_get_measure(struct als31300_data *data, + u16 *t, s16 *x, s16 *y, s16 *z) +{ + u32 buf[2]; + int ret, err; + + guard(mutex)(&data->mutex); + + ret = pm_runtime_resume_and_get(data->dev); + if (ret) + return ret; + + /* + * Loop until data is valid, new data should have the + * ALS31300_VOL_MSB_NEW_DATA bit set to 1. + * Max update rate is 2KHz, wait up to 1ms. + */ + ret = read_poll_timeout(regmap_bulk_read, err, + err || FIELD_GET(ALS31300_VOL_MSB_NEW_DATA, buf[0]), + 20, USEC_PER_MSEC, false, + data->map, ALS31300_VOL_MSB, buf, ARRAY_SIZE(buf)); + /* Bail out on read_poll_timeout() error */ + if (ret) + goto out; + + /* Bail out on regmap_bulk_read() error */ + if (err) { + dev_err(data->dev, "read data failed, error %d\n", ret); + ret = err; + goto out; + } + + *t = ALS31300_TEMPERATURE_GET(buf); + *x = ALS31300_DATA_X_GET(buf); + *y = ALS31300_DATA_Y_GET(buf); + *z = ALS31300_DATA_Z_GET(buf); + +out: + pm_runtime_mark_last_busy(data->dev); + pm_runtime_put_autosuspend(data->dev); + + return ret; +} + +static int als31300_read_raw(struct iio_dev *indio_dev, + const struct iio_chan_spec *chan, int *val, + int *val2, long mask) +{ + struct als31300_data *data = iio_priv(indio_dev); + s16 x, y, z; + u16 t; + int ret; + + switch (mask) { + case IIO_CHAN_INFO_PROCESSED: + case IIO_CHAN_INFO_RAW: + ret = als31300_get_measure(data, &t, &x, &y, &z); + if (ret) + return ret; + + switch (chan->address) { + case TEMPERATURE: + *val = t; + return IIO_VAL_INT; + case AXIS_X: + *val = x; + return IIO_VAL_INT; + case AXIS_Y: + *val = y; + return IIO_VAL_INT; + case AXIS_Z: + *val = z; + return IIO_VAL_INT; + default: + return -EINVAL; + } + case IIO_CHAN_INFO_SCALE: + switch (chan->type) { + case IIO_TEMP: + /* + * Fractional part of: + * 1000 * 302 * (value - 1708) + * temp = ---------------------------- + * 4096 + * to convert temperature in millicelcius. + */ + *val = MILLI * 302; + *val2 = 4096; + return IIO_VAL_FRACTIONAL; + case IIO_MAGN: + /* + * Devices are configured in factory + * with different sensitivities: + * - 500 GAUSS <-> 4 LSB/Gauss + * - 1000 GAUSS <-> 2 LSB/Gauss + * - 2000 GAUSS <-> 1 LSB/Gauss + * with translates by a division of the returned + * value to get Gauss value. + * The sensitivity cannot be read at runtime + * so the value depends on the model compatible + * or device id. + */ + *val = 1; + *val2 = data->variant_info->sensitivity; + return IIO_VAL_FRACTIONAL; + default: + return -EINVAL; + } + case IIO_CHAN_INFO_OFFSET: + switch (chan->type) { + case IIO_TEMP: + *val = -1708; + return IIO_VAL_INT; + default: + return -EINVAL; + } + default: + return -EINVAL; + } +} + +static irqreturn_t als31300_trigger_handler(int irq, void *p) +{ + struct iio_poll_func *pf = p; + struct iio_dev *indio_dev = pf->indio_dev; + struct als31300_data *data = iio_priv(indio_dev); + struct { + u16 temperature; + s16 channels[3]; + aligned_s64 timestamp; + } scan; + s16 x, y, z; + int ret; + u16 t; + + ret = als31300_get_measure(data, &t, &x, &y, &z); + if (ret) + goto trigger_out; + + scan.temperature = t; + scan.channels[0] = x; + scan.channels[1] = y; + scan.channels[2] = z; + iio_push_to_buffers_with_timestamp(indio_dev, &scan, + pf->timestamp); + +trigger_out: + iio_trigger_notify_done(indio_dev->trig); + + return IRQ_HANDLED; +} + +#define ALS31300_AXIS_CHANNEL(axis, index) \ + { \ + .type = IIO_MAGN, \ + .modified = 1, \ + .channel2 = IIO_MOD_##axis, \ + .info_mask_separate = BIT(IIO_CHAN_INFO_RAW) | \ + BIT(IIO_CHAN_INFO_SCALE), \ + .address = index, \ + .scan_index = index, \ + .scan_type = { \ + .sign = 's', \ + .realbits = 12, \ + .storagebits = 16, \ + .endianness = IIO_CPU, \ + }, \ + } + +static const struct iio_chan_spec als31300_channels[] = { + { + .type = IIO_TEMP, + .info_mask_separate = BIT(IIO_CHAN_INFO_RAW) | + BIT(IIO_CHAN_INFO_SCALE) | + BIT(IIO_CHAN_INFO_OFFSET), + .address = TEMPERATURE, + .scan_index = TEMPERATURE, + .scan_type = { + .sign = 'u', + .realbits = 16, + .storagebits = 16, + .endianness = IIO_CPU, + }, + }, + ALS31300_AXIS_CHANNEL(X, AXIS_X), + ALS31300_AXIS_CHANNEL(Y, AXIS_Y), + ALS31300_AXIS_CHANNEL(Z, AXIS_Z), + IIO_CHAN_SOFT_TIMESTAMP(4), +}; + +static const struct iio_info als31300_info = { + .read_raw = als31300_read_raw, +}; + +static int als31300_set_operating_mode(struct als31300_data *data, + unsigned int val) +{ + int ret; + + ret = regmap_update_bits(data->map, ALS31300_VOL_MODE, + ALS31300_VOL_MODE_SLEEP, val); + if (ret) { + dev_err(data->dev, "failed to set operating mode (%pe)\n", ERR_PTR(ret)); + return ret; + } + + /* The time it takes to exit sleep mode is equivalent to Power-On Delay Time */ + if (val == ALS31300_VOL_MODE_ACTIVE_MODE) + fsleep(600); + + return 0; +} + +static void als31300_power_down(void *data) +{ + als31300_set_operating_mode(data, ALS31300_VOL_MODE_SLEEP_MODE); +} + +static const struct iio_buffer_setup_ops als31300_setup_ops = {}; + +static const unsigned long als31300_scan_masks[] = { GENMASK(3, 0), 0 }; + +static bool als31300_volatile_reg(struct device *dev, unsigned int reg) +{ + return reg == ALS31300_VOL_MSB || reg == ALS31300_VOL_LSB; +} + +static const struct regmap_config als31300_regmap_config = { + .reg_bits = 8, + .val_bits = 32, + .max_register = ALS31300_CUSTOMER_ACCESS, + .volatile_reg = als31300_volatile_reg, +}; + +static int als31300_probe(struct i2c_client *i2c) +{ + struct device *dev = &i2c->dev; + struct als31300_data *data; + struct iio_dev *indio_dev; + int ret; + + indio_dev = devm_iio_device_alloc(dev, sizeof(*data)); + if (!indio_dev) + return -ENOMEM; + + data = iio_priv(indio_dev); + data->dev = dev; + i2c_set_clientdata(i2c, indio_dev); + + ret = devm_mutex_init(dev, &data->mutex); + if (ret) + return ret; + + data->variant_info = i2c_get_match_data(i2c); + if (!data->variant_info) + return -EINVAL; + + data->map = devm_regmap_init_i2c(i2c, &als31300_regmap_config); + if (IS_ERR(data->map)) + return dev_err_probe(dev, PTR_ERR(data->map), + "failed to allocate register map\n"); + + ret = devm_regulator_get_enable(dev, "vcc"); + if (ret) + return dev_err_probe(dev, ret, "failed to enable regulator\n"); + + ret = als31300_set_operating_mode(data, ALS31300_VOL_MODE_ACTIVE_MODE); + if (ret) + return dev_err_probe(dev, ret, "failed to power on device\n"); + + ret = devm_add_action_or_reset(dev, als31300_power_down, data); + if (ret) + return dev_err_probe(dev, ret, "failed to add powerdown action\n"); + + indio_dev->info = &als31300_info; + indio_dev->modes = INDIO_DIRECT_MODE; + indio_dev->name = i2c->name; + indio_dev->channels = als31300_channels; + indio_dev->num_channels = ARRAY_SIZE(als31300_channels); + indio_dev->available_scan_masks = als31300_scan_masks; + + ret = devm_iio_triggered_buffer_setup(dev, indio_dev, + iio_pollfunc_store_time, + als31300_trigger_handler, + &als31300_setup_ops); + if (ret < 0) + return dev_err_probe(dev, ret, "iio triggered buffer setup failed\n"); + + ret = pm_runtime_set_active(dev); + if (ret < 0) + return ret; + + ret = devm_pm_runtime_enable(dev); + if (ret) + return ret; + + pm_runtime_get_noresume(dev); + pm_runtime_set_autosuspend_delay(dev, 200); + pm_runtime_use_autosuspend(dev); + + pm_runtime_mark_last_busy(dev); + pm_runtime_put_autosuspend(dev); + + ret = devm_iio_device_register(dev, indio_dev); + if (ret) + return dev_err_probe(dev, ret, "device register failed\n"); + + return 0; +} + +static int als31300_runtime_suspend(struct device *dev) +{ + struct iio_dev *indio_dev = dev_get_drvdata(dev); + struct als31300_data *data = iio_priv(indio_dev); + + return als31300_set_operating_mode(data, ALS31300_VOL_MODE_SLEEP_MODE); +} + +static int als31300_runtime_resume(struct device *dev) +{ + struct iio_dev *indio_dev = dev_get_drvdata(dev); + struct als31300_data *data = iio_priv(indio_dev); + + return als31300_set_operating_mode(data, ALS31300_VOL_MODE_ACTIVE_MODE); +} + +static DEFINE_RUNTIME_DEV_PM_OPS(als31300_pm_ops, + als31300_runtime_suspend, als31300_runtime_resume, + NULL); + +static const struct als31300_variant_info al31300_variant_500 = { + .sensitivity = 4, +}; + +static const struct als31300_variant_info al31300_variant_1000 = { + .sensitivity = 2, +}; + +static const struct als31300_variant_info al31300_variant_2000 = { + .sensitivity = 1, +}; + +static const struct i2c_device_id als31300_id[] = { + { + .name = "als31300-500", + .driver_data = (kernel_ulong_t)&al31300_variant_500, + }, + { + .name = "als31300-1000", + .driver_data = (kernel_ulong_t)&al31300_variant_1000, + }, + { + .name = "als31300-2000", + .driver_data = (kernel_ulong_t)&al31300_variant_2000, + }, + { /* sentinel */ } +}; +MODULE_DEVICE_TABLE(i2c, als31300_id); + +static const struct of_device_id als31300_of_match[] = { + { + .compatible = "allegromicro,als31300-500", + .data = &al31300_variant_500, + }, + { + .compatible = "allegromicro,als31300-1000", + .data = &al31300_variant_1000, + }, + { + .compatible = "allegromicro,als31300-2000", + .data = &al31300_variant_2000, + }, + { /* sentinel */ } +}; +MODULE_DEVICE_TABLE(of, als31300_of_match); + +static struct i2c_driver als31300_driver = { + .driver = { + .name = "als31300", + .of_match_table = als31300_of_match, + .pm = pm_ptr(&als31300_pm_ops), + }, + .probe = als31300_probe, + .id_table = als31300_id, +}; +module_i2c_driver(als31300_driver); + +MODULE_LICENSE("GPL"); +MODULE_DESCRIPTION("ALS31300 3-D Linear Hall Effect Driver"); +MODULE_AUTHOR("Neil Armstrong <neil.armstrong@linaro.org>"); |