diff --git a/MAINTAINERS b/MAINTAINERS index f642044ada6c..c0951c9dc3c3 100644 --- a/MAINTAINERS +++ b/MAINTAINERS @@ -11607,6 +11607,13 @@ M: "Rafael J. Wysocki" S: Maintained F: drivers/pnp/ +PNI RM3100 IIO DRIVER +M: Song Qiang +L: linux-iio@vger.kernel.org +S: Maintained +F: drivers/iio/magnetometer/rm3100* +F: Documentation/devicetree/bindings/iio/magnetometer/pni,rm3100.txt + POSIX CLOCKS and TIMERS M: Thomas Gleixner L: linux-kernel@vger.kernel.org diff --git a/drivers/iio/magnetometer/Kconfig b/drivers/iio/magnetometer/Kconfig index ed9d776d01af..8a63cbbca4b7 100644 --- a/drivers/iio/magnetometer/Kconfig +++ b/drivers/iio/magnetometer/Kconfig @@ -175,4 +175,33 @@ config SENSORS_HMC5843_SPI - hmc5843_core (core functions) - hmc5843_spi (support for HMC5983) +config SENSORS_RM3100 + tristate + select IIO_BUFFER + select IIO_TRIGGERED_BUFFER + +config SENSORS_RM3100_I2C + tristate "PNI RM3100 3-Axis Magnetometer (I2C)" + depends on I2C + select SENSORS_RM3100 + select REGMAP_I2C + help + Say Y here to add support for the PNI RM3100 3-Axis Magnetometer. + + This driver can also be compiled as a module. + To compile this driver as a module, choose M here: the module + will be called rm3100-i2c. + +config SENSORS_RM3100_SPI + tristate "PNI RM3100 3-Axis Magnetometer (SPI)" + depends on SPI_MASTER + select SENSORS_RM3100 + select REGMAP_SPI + help + Say Y here to add support for the PNI RM3100 3-Axis Magnetometer. + + This driver can also be compiled as a module. + To compile this driver as a module, choose M here: the module + will be called rm3100-spi. + endmenu diff --git a/drivers/iio/magnetometer/Makefile b/drivers/iio/magnetometer/Makefile index 664b2f866472..ba1bc34b82fa 100644 --- a/drivers/iio/magnetometer/Makefile +++ b/drivers/iio/magnetometer/Makefile @@ -24,3 +24,7 @@ obj-$(CONFIG_IIO_ST_MAGN_SPI_3AXIS) += st_magn_spi.o obj-$(CONFIG_SENSORS_HMC5843) += hmc5843_core.o obj-$(CONFIG_SENSORS_HMC5843_I2C) += hmc5843_i2c.o obj-$(CONFIG_SENSORS_HMC5843_SPI) += hmc5843_spi.o + +obj-$(CONFIG_SENSORS_RM3100) += rm3100-core.o +obj-$(CONFIG_SENSORS_RM3100_I2C) += rm3100-i2c.o +obj-$(CONFIG_SENSORS_RM3100_SPI) += rm3100-spi.o diff --git a/drivers/iio/magnetometer/rm3100-core.c b/drivers/iio/magnetometer/rm3100-core.c new file mode 100644 index 000000000000..7c20918d8108 --- /dev/null +++ b/drivers/iio/magnetometer/rm3100-core.c @@ -0,0 +1,616 @@ +// SPDX-License-Identifier: GPL-2.0 +/* + * PNI RM3100 3-axis geomagnetic sensor driver core. + * + * Copyright (C) 2018 Song Qiang + * + * User Manual available at + * + * + * TODO: event generation, pm. + */ + +#include +#include +#include +#include + +#include +#include +#include +#include +#include +#include + +#include "rm3100.h" + +/* Cycle Count Registers. */ +#define RM3100_REG_CC_X 0x05 +#define RM3100_REG_CC_Y 0x07 +#define RM3100_REG_CC_Z 0x09 + +/* Poll Measurement Mode register. */ +#define RM3100_REG_POLL 0x00 +#define RM3100_POLL_X BIT(4) +#define RM3100_POLL_Y BIT(5) +#define RM3100_POLL_Z BIT(6) + +/* Continuous Measurement Mode register. */ +#define RM3100_REG_CMM 0x01 +#define RM3100_CMM_START BIT(0) +#define RM3100_CMM_X BIT(4) +#define RM3100_CMM_Y BIT(5) +#define RM3100_CMM_Z BIT(6) + +/* TiMe Rate Configuration register. */ +#define RM3100_REG_TMRC 0x0B +#define RM3100_TMRC_OFFSET 0x92 + +/* Result Status register. */ +#define RM3100_REG_STATUS 0x34 +#define RM3100_STATUS_DRDY BIT(7) + +/* Measurement result registers. */ +#define RM3100_REG_MX2 0x24 +#define RM3100_REG_MY2 0x27 +#define RM3100_REG_MZ2 0x2a + +#define RM3100_W_REG_START RM3100_REG_POLL +#define RM3100_W_REG_END RM3100_REG_TMRC +#define RM3100_R_REG_START RM3100_REG_POLL +#define RM3100_R_REG_END RM3100_REG_STATUS +#define RM3100_V_REG_START RM3100_REG_POLL +#define RM3100_V_REG_END RM3100_REG_STATUS + +/* + * This is computed by hand, is the sum of channel storage bits and padding + * bits, which is 4+4+4+12=24 in here. + */ +#define RM3100_SCAN_BYTES 24 + +#define RM3100_CMM_AXIS_SHIFT 4 + +struct rm3100_data { + struct regmap *regmap; + struct completion measuring_done; + bool use_interrupt; + int conversion_time; + int scale; + u8 buffer[RM3100_SCAN_BYTES]; + struct iio_trigger *drdy_trig; + + /* + * This lock is for protecting the consistency of series of i2c + * operations, that is, to make sure a measurement process will + * not be interrupted by a set frequency operation, which should + * be taken where a series of i2c operation starts, released where + * the operation ends. + */ + struct mutex lock; +}; + +static const struct regmap_range rm3100_readable_ranges[] = { + regmap_reg_range(RM3100_R_REG_START, RM3100_R_REG_END), +}; + +const struct regmap_access_table rm3100_readable_table = { + .yes_ranges = rm3100_readable_ranges, + .n_yes_ranges = ARRAY_SIZE(rm3100_readable_ranges), +}; +EXPORT_SYMBOL_GPL(rm3100_readable_table); + +static const struct regmap_range rm3100_writable_ranges[] = { + regmap_reg_range(RM3100_W_REG_START, RM3100_W_REG_END), +}; + +const struct regmap_access_table rm3100_writable_table = { + .yes_ranges = rm3100_writable_ranges, + .n_yes_ranges = ARRAY_SIZE(rm3100_writable_ranges), +}; +EXPORT_SYMBOL_GPL(rm3100_writable_table); + +static const struct regmap_range rm3100_volatile_ranges[] = { + regmap_reg_range(RM3100_V_REG_START, RM3100_V_REG_END), +}; + +const struct regmap_access_table rm3100_volatile_table = { + .yes_ranges = rm3100_volatile_ranges, + .n_yes_ranges = ARRAY_SIZE(rm3100_volatile_ranges), +}; +EXPORT_SYMBOL_GPL(rm3100_volatile_table); + +static irqreturn_t rm3100_thread_fn(int irq, void *d) +{ + struct iio_dev *indio_dev = d; + struct rm3100_data *data = iio_priv(indio_dev); + + /* + * Write operation to any register or read operation + * to first byte of results will clear the interrupt. + */ + regmap_write(data->regmap, RM3100_REG_POLL, 0); + + return IRQ_HANDLED; +} + +static irqreturn_t rm3100_irq_handler(int irq, void *d) +{ + struct iio_dev *indio_dev = d; + struct rm3100_data *data = iio_priv(indio_dev); + + switch (indio_dev->currentmode) { + case INDIO_DIRECT_MODE: + complete(&data->measuring_done); + break; + case INDIO_BUFFER_TRIGGERED: + iio_trigger_poll(data->drdy_trig); + break; + default: + dev_err(indio_dev->dev.parent, + "device mode out of control, current mode: %d", + indio_dev->currentmode); + } + + return IRQ_WAKE_THREAD; +} + +static int rm3100_wait_measurement(struct rm3100_data *data) +{ + struct regmap *regmap = data->regmap; + unsigned int val; + int tries = 20; + int ret; + + /* + * A read cycle of 400kbits i2c bus is about 20us, plus the time + * used for scheduling, a read cycle of fast mode of this device + * can reach 1.7ms, it may be possible for data to arrive just + * after we check the RM3100_REG_STATUS. In this case, irq_handler is + * called before measuring_done is reinitialized, it will wait + * forever for data that has already been ready. + * Reinitialize measuring_done before looking up makes sure we + * will always capture interrupt no matter when it happens. + */ + if (data->use_interrupt) + reinit_completion(&data->measuring_done); + + ret = regmap_read(regmap, RM3100_REG_STATUS, &val); + if (ret < 0) + return ret; + + if ((val & RM3100_STATUS_DRDY) != RM3100_STATUS_DRDY) { + if (data->use_interrupt) { + ret = wait_for_completion_timeout(&data->measuring_done, + msecs_to_jiffies(data->conversion_time)); + if (!ret) + return -ETIMEDOUT; + } else { + do { + usleep_range(1000, 5000); + + ret = regmap_read(regmap, RM3100_REG_STATUS, + &val); + if (ret < 0) + return ret; + + if (val & RM3100_STATUS_DRDY) + break; + } while (--tries); + if (!tries) + return -ETIMEDOUT; + } + } + return 0; +} + +static int rm3100_read_mag(struct rm3100_data *data, int idx, int *val) +{ + struct regmap *regmap = data->regmap; + u8 buffer[3]; + int ret; + + mutex_lock(&data->lock); + ret = regmap_write(regmap, RM3100_REG_POLL, BIT(4 + idx)); + if (ret < 0) + goto unlock_return; + + ret = rm3100_wait_measurement(data); + if (ret < 0) + goto unlock_return; + + ret = regmap_bulk_read(regmap, RM3100_REG_MX2 + 3 * idx, buffer, 3); + if (ret < 0) + goto unlock_return; + mutex_unlock(&data->lock); + + *val = sign_extend32((buffer[0] << 16) | (buffer[1] << 8) | buffer[2], + 23); + + return IIO_VAL_INT; + +unlock_return: + mutex_unlock(&data->lock); + return ret; +} + +#define RM3100_CHANNEL(axis, idx) \ + { \ + .type = IIO_MAGN, \ + .modified = 1, \ + .channel2 = IIO_MOD_##axis, \ + .info_mask_separate = BIT(IIO_CHAN_INFO_RAW), \ + .info_mask_shared_by_type = BIT(IIO_CHAN_INFO_SCALE) | \ + BIT(IIO_CHAN_INFO_SAMP_FREQ), \ + .scan_index = idx, \ + .scan_type = { \ + .sign = 's', \ + .realbits = 24, \ + .storagebits = 32, \ + .shift = 8, \ + .endianness = IIO_BE, \ + }, \ + } + +static const struct iio_chan_spec rm3100_channels[] = { + RM3100_CHANNEL(X, 0), + RM3100_CHANNEL(Y, 1), + RM3100_CHANNEL(Z, 2), + IIO_CHAN_SOFT_TIMESTAMP(3), +}; + +static IIO_CONST_ATTR_SAMP_FREQ_AVAIL( + "600 300 150 75 37 18 9 4.5 2.3 1.2 0.6 0.3 0.015 0.075" +); + +static struct attribute *rm3100_attributes[] = { + &iio_const_attr_sampling_frequency_available.dev_attr.attr, + NULL, +}; + +static const struct attribute_group rm3100_attribute_group = { + .attrs = rm3100_attributes, +}; + +#define RM3100_SAMP_NUM 14 + +/* + * Frequency : rm3100_samp_rates[][0].rm3100_samp_rates[][1]Hz. + * Time between reading: rm3100_sam_rates[][2]ms. + * The first one is actually 1.7ms. + */ +static const int rm3100_samp_rates[RM3100_SAMP_NUM][3] = { + {600, 0, 2}, {300, 0, 3}, {150, 0, 7}, {75, 0, 13}, {37, 0, 27}, + {18, 0, 55}, {9, 0, 110}, {4, 500000, 220}, {2, 300000, 440}, + {1, 200000, 800}, {0, 600000, 1600}, {0, 300000, 3300}, + {0, 15000, 6700}, {0, 75000, 13000} +}; + +static int rm3100_get_samp_freq(struct rm3100_data *data, int *val, int *val2) +{ + unsigned int tmp; + int ret; + + mutex_lock(&data->lock); + ret = regmap_read(data->regmap, RM3100_REG_TMRC, &tmp); + mutex_unlock(&data->lock); + if (ret < 0) + return ret; + *val = rm3100_samp_rates[tmp - RM3100_TMRC_OFFSET][0]; + *val2 = rm3100_samp_rates[tmp - RM3100_TMRC_OFFSET][1]; + + return IIO_VAL_INT_PLUS_MICRO; +} + +static int rm3100_set_cycle_count(struct rm3100_data *data, int val) +{ + int ret; + u8 i; + + for (i = 0; i < 3; i++) { + ret = regmap_write(data->regmap, RM3100_REG_CC_X + 2 * i, val); + if (ret < 0) + return ret; + } + + /* + * The scale of this sensor depends on the cycle count value, these + * three values are corresponding to the cycle count value 50, 100, + * 200. scale = output / gain * 10^4. + */ + switch (val) { + case 50: + data->scale = 500; + break; + case 100: + data->scale = 263; + break; + /* + * case 200: + * This function will never be called by users' code, so here we + * assume that it will never get a wrong parameter. + */ + default: + data->scale = 133; + } + + return 0; +} + +static int rm3100_set_samp_freq(struct iio_dev *indio_dev, int val, int val2) +{ + struct rm3100_data *data = iio_priv(indio_dev); + struct regmap *regmap = data->regmap; + unsigned int cycle_count; + int ret; + int i; + + mutex_lock(&data->lock); + /* All cycle count registers use the same value. */ + ret = regmap_read(regmap, RM3100_REG_CC_X, &cycle_count); + if (ret < 0) + goto unlock_return; + + for (i = 0; i < RM3100_SAMP_NUM; i++) { + if (val == rm3100_samp_rates[i][0] && + val2 == rm3100_samp_rates[i][1]) + break; + } + if (i == RM3100_SAMP_NUM) { + ret = -EINVAL; + goto unlock_return; + } + + ret = regmap_write(regmap, RM3100_REG_TMRC, i + RM3100_TMRC_OFFSET); + if (ret < 0) + goto unlock_return; + + /* Checking if cycle count registers need changing. */ + if (val == 600 && cycle_count == 200) { + ret = rm3100_set_cycle_count(data, 100); + if (ret < 0) + goto unlock_return; + } else if (val != 600 && cycle_count == 100) { + ret = rm3100_set_cycle_count(data, 200); + if (ret < 0) + goto unlock_return; + } + + if (indio_dev->currentmode == INDIO_BUFFER_TRIGGERED) { + /* Writing TMRC registers requires CMM reset. */ + ret = regmap_write(regmap, RM3100_REG_CMM, 0); + if (ret < 0) + goto unlock_return; + ret = regmap_write(data->regmap, RM3100_REG_CMM, + (*indio_dev->active_scan_mask & 0x7) << + RM3100_CMM_AXIS_SHIFT | RM3100_CMM_START); + if (ret < 0) + goto unlock_return; + } + mutex_unlock(&data->lock); + + data->conversion_time = rm3100_samp_rates[i][2] * 2; + return 0; + +unlock_return: + mutex_unlock(&data->lock); + return ret; +} + +static int rm3100_read_raw(struct iio_dev *indio_dev, + const struct iio_chan_spec *chan, + int *val, int *val2, long mask) +{ + struct rm3100_data *data = iio_priv(indio_dev); + int ret; + + switch (mask) { + case IIO_CHAN_INFO_RAW: + ret = iio_device_claim_direct_mode(indio_dev); + if (ret < 0) + return ret; + + ret = rm3100_read_mag(data, chan->scan_index, val); + iio_device_release_direct_mode(indio_dev); + + return ret; + case IIO_CHAN_INFO_SCALE: + *val = 0; + *val2 = data->scale; + + return IIO_VAL_INT_PLUS_MICRO; + case IIO_CHAN_INFO_SAMP_FREQ: + return rm3100_get_samp_freq(data, val, val2); + default: + return -EINVAL; + } +} + +static int rm3100_write_raw(struct iio_dev *indio_dev, + struct iio_chan_spec const *chan, + int val, int val2, long mask) +{ + switch (mask) { + case IIO_CHAN_INFO_SAMP_FREQ: + return rm3100_set_samp_freq(indio_dev, val, val2); + default: + return -EINVAL; + } +} + +static const struct iio_info rm3100_info = { + .attrs = &rm3100_attribute_group, + .read_raw = rm3100_read_raw, + .write_raw = rm3100_write_raw, +}; + +static int rm3100_buffer_preenable(struct iio_dev *indio_dev) +{ + struct rm3100_data *data = iio_priv(indio_dev); + + /* Starting channels enabled. */ + return regmap_write(data->regmap, RM3100_REG_CMM, + (*indio_dev->active_scan_mask & 0x7) << RM3100_CMM_AXIS_SHIFT | + RM3100_CMM_START); +} + +static int rm3100_buffer_postdisable(struct iio_dev *indio_dev) +{ + struct rm3100_data *data = iio_priv(indio_dev); + + return regmap_write(data->regmap, RM3100_REG_CMM, 0); +} + +static const struct iio_buffer_setup_ops rm3100_buffer_ops = { + .preenable = rm3100_buffer_preenable, + .postenable = iio_triggered_buffer_postenable, + .predisable = iio_triggered_buffer_predisable, + .postdisable = rm3100_buffer_postdisable, +}; + +static irqreturn_t rm3100_trigger_handler(int irq, void *p) +{ + struct iio_poll_func *pf = p; + struct iio_dev *indio_dev = pf->indio_dev; + unsigned long scan_mask = *indio_dev->active_scan_mask; + unsigned int mask_len = indio_dev->masklength; + struct rm3100_data *data = iio_priv(indio_dev); + struct regmap *regmap = data->regmap; + int ret, i, bit; + + mutex_lock(&data->lock); + switch (scan_mask) { + case BIT(0) | BIT(1) | BIT(2): + ret = regmap_bulk_read(regmap, RM3100_REG_MX2, data->buffer, 9); + mutex_unlock(&data->lock); + if (ret < 0) + goto done; + /* Convert XXXYYYZZZxxx to XXXxYYYxZZZx. x for paddings. */ + for (i = 2; i > 0; i--) + memmove(data->buffer + i * 4, data->buffer + i * 3, 3); + break; + case BIT(0) | BIT(1): + ret = regmap_bulk_read(regmap, RM3100_REG_MX2, data->buffer, 6); + mutex_unlock(&data->lock); + if (ret < 0) + goto done; + memmove(data->buffer + 4, data->buffer + 3, 3); + break; + case BIT(1) | BIT(2): + ret = regmap_bulk_read(regmap, RM3100_REG_MY2, data->buffer, 6); + mutex_unlock(&data->lock); + if (ret < 0) + goto done; + memmove(data->buffer + 4, data->buffer + 3, 3); + break; + case BIT(0) | BIT(2): + ret = regmap_bulk_read(regmap, RM3100_REG_MX2, data->buffer, 9); + mutex_unlock(&data->lock); + if (ret < 0) + goto done; + memmove(data->buffer + 4, data->buffer + 6, 3); + break; + default: + for_each_set_bit(bit, &scan_mask, mask_len) { + ret = regmap_bulk_read(regmap, RM3100_REG_MX2 + 3 * bit, + data->buffer, 3); + if (ret < 0) { + mutex_unlock(&data->lock); + goto done; + } + } + mutex_unlock(&data->lock); + } + /* + * Always using the same buffer so that we wouldn't need to set the + * paddings to 0 in case of leaking any data. + */ + iio_push_to_buffers_with_timestamp(indio_dev, data->buffer, + pf->timestamp); +done: + iio_trigger_notify_done(indio_dev->trig); + + return IRQ_HANDLED; +} + +int rm3100_common_probe(struct device *dev, struct regmap *regmap, int irq) +{ + struct iio_dev *indio_dev; + struct rm3100_data *data; + unsigned int tmp; + int ret; + + indio_dev = devm_iio_device_alloc(dev, sizeof(*data)); + if (!indio_dev) + return -ENOMEM; + + data = iio_priv(indio_dev); + data->regmap = regmap; + + mutex_init(&data->lock); + + indio_dev->dev.parent = dev; + indio_dev->name = "rm3100"; + indio_dev->info = &rm3100_info; + indio_dev->channels = rm3100_channels; + indio_dev->num_channels = ARRAY_SIZE(rm3100_channels); + indio_dev->modes = INDIO_DIRECT_MODE | INDIO_BUFFER_TRIGGERED; + indio_dev->currentmode = INDIO_DIRECT_MODE; + + if (!irq) + data->use_interrupt = false; + else { + data->use_interrupt = true; + + init_completion(&data->measuring_done); + ret = devm_request_threaded_irq(dev, + irq, + rm3100_irq_handler, + rm3100_thread_fn, + IRQF_TRIGGER_HIGH | + IRQF_ONESHOT, + indio_dev->name, + indio_dev); + if (ret < 0) { + dev_err(dev, "request irq line failed.\n"); + return ret; + } + + data->drdy_trig = devm_iio_trigger_alloc(dev, "%s-drdy%d", + indio_dev->name, + indio_dev->id); + if (!data->drdy_trig) + return -ENOMEM; + + data->drdy_trig->dev.parent = dev; + ret = devm_iio_trigger_register(dev, data->drdy_trig); + if (ret < 0) + return ret; + } + + ret = devm_iio_triggered_buffer_setup(dev, indio_dev, + &iio_pollfunc_store_time, + rm3100_trigger_handler, + &rm3100_buffer_ops); + if (ret < 0) + return ret; + + ret = regmap_read(regmap, RM3100_REG_TMRC, &tmp); + if (ret < 0) + return ret; + /* Initializing max wait time, which is double conversion time. */ + data->conversion_time = rm3100_samp_rates[tmp - RM3100_TMRC_OFFSET][2] + * 2; + + /* Cycle count values may not be what we want. */ + if ((tmp - RM3100_TMRC_OFFSET) == 0) + rm3100_set_cycle_count(data, 100); + else + rm3100_set_cycle_count(data, 200); + + return devm_iio_device_register(dev, indio_dev); +} +EXPORT_SYMBOL_GPL(rm3100_common_probe); + +MODULE_AUTHOR("Song Qiang "); +MODULE_DESCRIPTION("PNI RM3100 3-axis magnetometer i2c driver"); +MODULE_LICENSE("GPL v2"); diff --git a/drivers/iio/magnetometer/rm3100-i2c.c b/drivers/iio/magnetometer/rm3100-i2c.c new file mode 100644 index 000000000000..1ac622c6d6c9 --- /dev/null +++ b/drivers/iio/magnetometer/rm3100-i2c.c @@ -0,0 +1,54 @@ +// SPDX-License-Identifier: GPL-2.0 +/* + * Support for PNI RM3100 3-axis geomagnetic sensor on a i2c bus. + * + * Copyright (C) 2018 Song Qiang + * + * i2c slave address: 0x20 + SA1 << 1 + SA0. + */ + +#include +#include + +#include "rm3100.h" + +static const struct regmap_config rm3100_regmap_config = { + .reg_bits = 8, + .val_bits = 8, + + .rd_table = &rm3100_readable_table, + .wr_table = &rm3100_writable_table, + .volatile_table = &rm3100_volatile_table, + + .cache_type = REGCACHE_RBTREE, +}; + +static int rm3100_probe(struct i2c_client *client) +{ + struct regmap *regmap; + + regmap = devm_regmap_init_i2c(client, &rm3100_regmap_config); + if (IS_ERR(regmap)) + return PTR_ERR(regmap); + + return rm3100_common_probe(&client->dev, regmap, client->irq); +} + +static const struct of_device_id rm3100_dt_match[] = { + { .compatible = "pni,rm3100", }, + { } +}; +MODULE_DEVICE_TABLE(of, rm3100_dt_match); + +static struct i2c_driver rm3100_driver = { + .driver = { + .name = "rm3100-i2c", + .of_match_table = rm3100_dt_match, + }, + .probe_new = rm3100_probe, +}; +module_i2c_driver(rm3100_driver); + +MODULE_AUTHOR("Song Qiang "); +MODULE_DESCRIPTION("PNI RM3100 3-axis magnetometer i2c driver"); +MODULE_LICENSE("GPL v2"); diff --git a/drivers/iio/magnetometer/rm3100-spi.c b/drivers/iio/magnetometer/rm3100-spi.c new file mode 100644 index 000000000000..65d5eb9e4f5e --- /dev/null +++ b/drivers/iio/magnetometer/rm3100-spi.c @@ -0,0 +1,64 @@ +// SPDX-License-Identifier: GPL-2.0 +/* + * Support for PNI RM3100 3-axis geomagnetic sensor on a spi bus. + * + * Copyright (C) 2018 Song Qiang + */ + +#include +#include + +#include "rm3100.h" + +static const struct regmap_config rm3100_regmap_config = { + .reg_bits = 8, + .val_bits = 8, + + .rd_table = &rm3100_readable_table, + .wr_table = &rm3100_writable_table, + .volatile_table = &rm3100_volatile_table, + + .read_flag_mask = 0x80, + + .cache_type = REGCACHE_RBTREE, +}; + +static int rm3100_probe(struct spi_device *spi) +{ + struct regmap *regmap; + int ret; + + /* Actually this device supports both mode 0 and mode 3. */ + spi->mode = SPI_MODE_0; + /* Data rates cannot exceed 1Mbits. */ + spi->max_speed_hz = 1000000; + spi->bits_per_word = 8; + ret = spi_setup(spi); + if (ret) + return ret; + + regmap = devm_regmap_init_spi(spi, &rm3100_regmap_config); + if (IS_ERR(regmap)) + return PTR_ERR(regmap); + + return rm3100_common_probe(&spi->dev, regmap, spi->irq); +} + +static const struct of_device_id rm3100_dt_match[] = { + { .compatible = "pni,rm3100", }, + { } +}; +MODULE_DEVICE_TABLE(of, rm3100_dt_match); + +static struct spi_driver rm3100_driver = { + .driver = { + .name = "rm3100-spi", + .of_match_table = rm3100_dt_match, + }, + .probe = rm3100_probe, +}; +module_spi_driver(rm3100_driver); + +MODULE_AUTHOR("Song Qiang "); +MODULE_DESCRIPTION("PNI RM3100 3-axis magnetometer spi driver"); +MODULE_LICENSE("GPL v2"); diff --git a/drivers/iio/magnetometer/rm3100.h b/drivers/iio/magnetometer/rm3100.h new file mode 100644 index 000000000000..c3508218bc77 --- /dev/null +++ b/drivers/iio/magnetometer/rm3100.h @@ -0,0 +1,17 @@ +/* SPDX-License-Identifier: GPL-2.0 */ +/* + * Copyright (C) 2018 Song Qiang + */ + +#ifndef RM3100_CORE_H +#define RM3100_CORE_H + +#include + +extern const struct regmap_access_table rm3100_readable_table; +extern const struct regmap_access_table rm3100_writable_table; +extern const struct regmap_access_table rm3100_volatile_table; + +int rm3100_common_probe(struct device *dev, struct regmap *regmap, int irq); + +#endif /* RM3100_CORE_H */