diff options
Diffstat (limited to 'drivers/iio')
| -rw-r--r-- | drivers/iio/magnetometer/Kconfig | 11 | ||||
| -rw-r--r-- | drivers/iio/magnetometer/Makefile | 1 | ||||
| -rw-r--r-- | drivers/iio/magnetometer/mmc35240.c | 469 |
3 files changed, 481 insertions, 0 deletions
diff --git a/drivers/iio/magnetometer/Kconfig b/drivers/iio/magnetometer/Kconfig index 9746a2a88640..dcadfc4f0661 100644 --- a/drivers/iio/magnetometer/Kconfig +++ b/drivers/iio/magnetometer/Kconfig @@ -47,6 +47,17 @@ config HID_SENSOR_MAGNETOMETER_3D Say yes here to build support for the HID SENSOR Magnetometer 3D. +config MMC35240 + tristate "MEMSIC MMC35240 3-axis magnetic sensor" + select REGMAP_I2C + depends on I2C + help + Say yes here to build support for the MEMSIC MMC35240 3-axis + magnetic sensor. + + To compile this driver as a module, choose M here: the module + will be called mmc35240. + config IIO_ST_MAGN_3AXIS tristate "STMicroelectronics magnetometers 3-Axis Driver" depends on (I2C || SPI_MASTER) && SYSFS diff --git a/drivers/iio/magnetometer/Makefile b/drivers/iio/magnetometer/Makefile index e2c34594ff3f..33b1d4d54ee7 100644 --- a/drivers/iio/magnetometer/Makefile +++ b/drivers/iio/magnetometer/Makefile @@ -6,6 +6,7 @@ obj-$(CONFIG_AK8975) += ak8975.o obj-$(CONFIG_MAG3110) += mag3110.o obj-$(CONFIG_HID_SENSOR_MAGNETOMETER_3D) += hid-sensor-magn-3d.o +obj-$(CONFIG_MMC35240) += mmc35240.o obj-$(CONFIG_IIO_ST_MAGN_3AXIS) += st_magn.o st_magn-y := st_magn_core.o diff --git a/drivers/iio/magnetometer/mmc35240.c b/drivers/iio/magnetometer/mmc35240.c new file mode 100644 index 000000000000..46728006bbdb --- /dev/null +++ b/drivers/iio/magnetometer/mmc35240.c @@ -0,0 +1,469 @@ +/* + * MMC35240 - MEMSIC 3-axis Magnetic Sensor + * + * Copyright (c) 2015, Intel Corporation. + * + * This file is subject to the terms and conditions of version 2 of + * the GNU General Public License. See the file COPYING in the main + * directory of this archive for more details. + * + * IIO driver for MMC35240 (7-bit I2C slave address 0x30). + * + * TODO: offset, ACPI, continuous measurement mode, PM + */ + +#include <linux/module.h> +#include <linux/init.h> +#include <linux/i2c.h> +#include <linux/delay.h> +#include <linux/regmap.h> + +#include <linux/iio/iio.h> +#include <linux/iio/sysfs.h> + +#define MMC35240_DRV_NAME "mmc35240" +#define MMC35240_REGMAP_NAME "mmc35240_regmap" + +#define MMC35240_REG_XOUT_L 0x00 +#define MMC35240_REG_XOUT_H 0x01 +#define MMC35240_REG_YOUT_L 0x02 +#define MMC35240_REG_YOUT_H 0x03 +#define MMC35240_REG_ZOUT_L 0x04 +#define MMC35240_REG_ZOUT_H 0x05 + +#define MMC35240_REG_STATUS 0x06 +#define MMC35240_REG_CTRL0 0x07 +#define MMC35240_REG_CTRL1 0x08 + +#define MMC35240_REG_ID 0x20 + +#define MMC35240_STATUS_MEAS_DONE_BIT BIT(0) + +#define MMC35240_CTRL0_REFILL_BIT BIT(7) +#define MMC35240_CTRL0_RESET_BIT BIT(6) +#define MMC35240_CTRL0_SET_BIT BIT(5) +#define MMC35240_CTRL0_CMM_BIT BIT(1) +#define MMC35240_CTRL0_TM_BIT BIT(0) + +/* output resolution bits */ +#define MMC35240_CTRL1_BW0_BIT BIT(0) +#define MMC35240_CTRL1_BW1_BIT BIT(1) + +#define MMC35240_CTRL1_BW_MASK (MMC35240_CTRL1_BW0_BIT | \ + MMC35240_CTRL1_BW1_BIT) +#define MMC35240_CTRL1_BW_SHIFT 0 + +#define MMC35240_WAIT_CHARGE_PUMP 50000 /* us */ +#define MMC53240_WAIT_SET_RESET 1000 /* us */ + +enum mmc35240_resolution { + MMC35240_16_BITS_SLOW = 0, /* 100 Hz */ + MMC35240_16_BITS_FAST, /* 200 Hz */ + MMC35240_14_BITS, /* 333 Hz */ + MMC35240_12_BITS, /* 666 Hz */ +}; + +enum mmc35240_axis { + AXIS_X = 0, + AXIS_Y, + AXIS_Z, +}; + +static const struct { + int sens[3]; /* sensitivity per X, Y, Z axis */ + int nfo; /* null field output */ +} mmc35240_props_table[] = { + /* 16 bits, 100Hz ODR */ + { + {1024, 1024, 770}, + 32768, + }, + /* 16 bits, 200Hz ODR */ + { + {1024, 1024, 770}, + 32768, + }, + /* 14 bits, 333Hz ODR */ + { + {256, 256, 193}, + 8192, + }, + /* 12 bits, 666Hz ODR */ + { + {64, 64, 48}, + 2048, + }, +}; + +struct mmc35240_data { + struct i2c_client *client; + struct mutex mutex; + struct regmap *regmap; + enum mmc35240_resolution res; +}; + +static const int mmc35240_samp_freq[] = {100, 200, 333, 666}; + +static IIO_CONST_ATTR_SAMP_FREQ_AVAIL("100 200 333 666"); + +#define MMC35240_CHANNEL(_axis) { \ + .type = IIO_MAGN, \ + .modified = 1, \ + .channel2 = IIO_MOD_ ## _axis, \ + .address = AXIS_ ## _axis, \ + .info_mask_separate = BIT(IIO_CHAN_INFO_PROCESSED), \ + .info_mask_shared_by_type = BIT(IIO_CHAN_INFO_SAMP_FREQ), \ +} + +static const struct iio_chan_spec mmc35240_channels[] = { + MMC35240_CHANNEL(X), + MMC35240_CHANNEL(Y), + MMC35240_CHANNEL(Z), +}; + +static struct attribute *mmc35240_attributes[] = { + &iio_const_attr_sampling_frequency_available.dev_attr.attr, +}; + +static const struct attribute_group mmc35240_attribute_group = { + .attrs = mmc35240_attributes, +}; + +static int mmc35240_get_samp_freq_index(struct mmc35240_data *data, + int val, int val2) +{ + int i; + + for (i = 0; i < ARRAY_SIZE(mmc35240_samp_freq); i++) + if (mmc35240_samp_freq[i] == val) + return i; + return -EINVAL; +} + +static int mmc35240_hw_set(struct mmc35240_data *data, bool set) +{ + int ret; + u8 coil_bit; + + /* + * Recharge the capacitor at VCAP pin, requested to be issued + * before a SET/RESET command. + */ + ret = regmap_update_bits(data->regmap, MMC35240_REG_CTRL0, + MMC35240_CTRL0_REFILL_BIT, + MMC35240_CTRL0_REFILL_BIT); + if (ret < 0) + return ret; + usleep_range(MMC35240_WAIT_CHARGE_PUMP, MMC35240_WAIT_CHARGE_PUMP + 1); + + if (set) + coil_bit = MMC35240_CTRL0_SET_BIT; + else + coil_bit = MMC35240_CTRL0_RESET_BIT; + + return regmap_update_bits(data->regmap, MMC35240_REG_CTRL0, + MMC35240_CTRL0_REFILL_BIT, + coil_bit); +} + +static int mmc35240_init(struct mmc35240_data *data) +{ + int ret; + unsigned int reg_id; + + ret = regmap_read(data->regmap, MMC35240_REG_ID, ®_id); + if (ret < 0) { + dev_err(&data->client->dev, "Error reading product id\n"); + return ret; + } + + dev_dbg(&data->client->dev, "MMC35240 chip id %x\n", reg_id); + + /* + * make sure we restore sensor characteristics, by doing + * a RESET/SET sequence + */ + ret = mmc35240_hw_set(data, false); + if (ret < 0) + return ret; + usleep_range(MMC53240_WAIT_SET_RESET, MMC53240_WAIT_SET_RESET + 1); + + ret = mmc35240_hw_set(data, true); + if (ret < 0) + return ret; + + /* set default sampling frequency */ + return regmap_update_bits(data->regmap, MMC35240_REG_CTRL1, + MMC35240_CTRL1_BW_MASK, + data->res << MMC35240_CTRL1_BW_SHIFT); +} + +static int mmc35240_take_measurement(struct mmc35240_data *data) +{ + int ret, tries = 100; + unsigned int reg_status; + + ret = regmap_write(data->regmap, MMC35240_REG_CTRL0, + MMC35240_CTRL0_TM_BIT); + if (ret < 0) + return ret; + + while (tries-- > 0) { + ret = regmap_read(data->regmap, MMC35240_REG_STATUS, + ®_status); + if (ret < 0) + return ret; + if (reg_status & MMC35240_STATUS_MEAS_DONE_BIT) + break; + msleep(20); + } + + if (tries < 0) { + dev_err(&data->client->dev, "data not ready\n"); + return -EIO; + } + + return 0; +} + +static int mmc35240_read_measurement(struct mmc35240_data *data, __le16 buf[3]) +{ + int ret; + + ret = mmc35240_take_measurement(data); + if (ret < 0) + return ret; + + return regmap_bulk_read(data->regmap, MMC35240_REG_XOUT_L, (u8 *)buf, + 3 * sizeof(__le16)); +} + +static int mmc35240_raw_to_gauss(struct mmc35240_data *data, int index, + __le16 buf[], + int *val, int *val2) +{ + int raw_x, raw_y, raw_z; + int sens_x, sens_y, sens_z; + int nfo; + + raw_x = le16_to_cpu(buf[AXIS_X]); + raw_y = le16_to_cpu(buf[AXIS_Y]); + raw_z = le16_to_cpu(buf[AXIS_Z]); + + sens_x = mmc35240_props_table[data->res].sens[AXIS_X]; + sens_y = mmc35240_props_table[data->res].sens[AXIS_Y]; + sens_z = mmc35240_props_table[data->res].sens[AXIS_Z]; + + nfo = mmc35240_props_table[data->res].nfo; + + switch (index) { + case AXIS_X: + *val = (raw_x - nfo) / sens_x; + *val2 = ((raw_x - nfo) % sens_x) * 1000000; + break; + case AXIS_Y: + *val = (raw_y - nfo) / sens_y - (raw_z - nfo) / sens_z; + *val2 = (((raw_y - nfo) % sens_y - (raw_z - nfo) % sens_z)) + * 1000000; + break; + case AXIS_Z: + *val = (raw_y - nfo) / sens_y + (raw_z - nfo) / sens_z; + *val2 = (((raw_y - nfo) % sens_y + (raw_z - nfo) % sens_z)) + * 1000000; + break; + default: + return -EINVAL; + } + return 0; +} + +static int mmc35240_read_raw(struct iio_dev *indio_dev, + struct iio_chan_spec const *chan, int *val, + int *val2, long mask) +{ + struct mmc35240_data *data = iio_priv(indio_dev); + int ret, i; + unsigned int reg; + __le16 buf[3]; + + switch (mask) { + case IIO_CHAN_INFO_PROCESSED: + mutex_lock(&data->mutex); + ret = mmc35240_read_measurement(data, buf); + mutex_unlock(&data->mutex); + if (ret < 0) + return ret; + ret = mmc35240_raw_to_gauss(data, chan->address, + buf, val, val2); + if (ret < 0) + return ret; + return IIO_VAL_INT_PLUS_MICRO; + case IIO_CHAN_INFO_SAMP_FREQ: + mutex_lock(&data->mutex); + ret = regmap_read(data->regmap, MMC35240_REG_CTRL1, ®); + mutex_unlock(&data->mutex); + if (ret < 0) + return ret; + + i = (reg & MMC35240_CTRL1_BW_MASK) >> MMC35240_CTRL1_BW_SHIFT; + if (i < 0 || i > ARRAY_SIZE(mmc35240_samp_freq)) + return -EINVAL; + + *val = mmc35240_samp_freq[i]; + *val2 = 0; + return IIO_VAL_INT; + default: + return -EINVAL; + } +} + +static int mmc35240_write_raw(struct iio_dev *indio_dev, + struct iio_chan_spec const *chan, int val, + int val2, long mask) +{ + struct mmc35240_data *data = iio_priv(indio_dev); + int i, ret; + + switch (mask) { + case IIO_CHAN_INFO_SAMP_FREQ: + i = mmc35240_get_samp_freq_index(data, val, val2); + if (i < 0) + return -EINVAL; + mutex_lock(&data->mutex); + ret = regmap_update_bits(data->regmap, MMC35240_REG_CTRL1, + MMC35240_CTRL1_BW_MASK, + i << MMC35240_CTRL1_BW_SHIFT); + mutex_unlock(&data->mutex); + return ret; + default: + return -EINVAL; + } +} + +static const struct iio_info mmc35240_info = { + .driver_module = THIS_MODULE, + .read_raw = mmc35240_read_raw, + .write_raw = mmc35240_write_raw, + .attrs = &mmc35240_attribute_group, +}; + +static bool mmc35240_is_writeable_reg(struct device *dev, unsigned int reg) +{ + switch (reg) { + case MMC35240_REG_CTRL0: + case MMC35240_REG_CTRL1: + return true; + default: + return false; + } +} + +static bool mmc35240_is_readable_reg(struct device *dev, unsigned int reg) +{ + switch (reg) { + case MMC35240_REG_XOUT_L: + case MMC35240_REG_XOUT_H: + case MMC35240_REG_YOUT_L: + case MMC35240_REG_YOUT_H: + case MMC35240_REG_ZOUT_L: + case MMC35240_REG_ZOUT_H: + case MMC35240_REG_STATUS: + case MMC35240_REG_ID: + return true; + default: + return false; + } +} + +static bool mmc35240_is_volatile_reg(struct device *dev, unsigned int reg) +{ + switch (reg) { + case MMC35240_REG_CTRL0: + case MMC35240_REG_CTRL1: + return false; + default: + return true; + } +} + +static struct reg_default mmc35240_reg_defaults[] = { + { MMC35240_REG_CTRL0, 0x00 }, + { MMC35240_REG_CTRL1, 0x00 }, +}; + +static const struct regmap_config mmc35240_regmap_config = { + .name = MMC35240_REGMAP_NAME, + + .reg_bits = 8, + .val_bits = 8, + + .max_register = MMC35240_REG_ID, + .cache_type = REGCACHE_FLAT, + + .writeable_reg = mmc35240_is_writeable_reg, + .readable_reg = mmc35240_is_readable_reg, + .volatile_reg = mmc35240_is_volatile_reg, + + .reg_defaults = mmc35240_reg_defaults, + .num_reg_defaults = ARRAY_SIZE(mmc35240_reg_defaults), +}; + +static int mmc35240_probe(struct i2c_client *client, + const struct i2c_device_id *id) +{ + struct mmc35240_data *data; + struct iio_dev *indio_dev; + struct regmap *regmap; + int ret; + + indio_dev = devm_iio_device_alloc(&client->dev, sizeof(*data)); + if (!indio_dev) + return -ENOMEM; + + regmap = devm_regmap_init_i2c(client, &mmc35240_regmap_config); + if (IS_ERR(regmap)) { + dev_err(&client->dev, "regmap initialization failed\n"); + return PTR_ERR(regmap); + } + + data = iio_priv(indio_dev); + data->client = client; + data->regmap = regmap; + data->res = MMC35240_16_BITS_SLOW; + + mutex_init(&data->mutex); + + indio_dev->dev.parent = &client->dev; + indio_dev->info = &mmc35240_info; + indio_dev->name = MMC35240_DRV_NAME; + indio_dev->channels = mmc35240_channels; + indio_dev->num_channels = ARRAY_SIZE(mmc35240_channels); + indio_dev->modes = INDIO_DIRECT_MODE; + + ret = mmc35240_init(data); + if (ret < 0) { + dev_err(&client->dev, "mmc35240 chip init failed\n"); + return ret; + } + return devm_iio_device_register(&client->dev, indio_dev); +} + +static const struct i2c_device_id mmc35240_id[] = { + {"MMC35240", 0}, + {} +}; +MODULE_DEVICE_TABLE(i2c, mmc35240_id); + +static struct i2c_driver mmc35240_driver = { + .driver = { + .name = MMC35240_DRV_NAME, + }, + .probe = mmc35240_probe, + .id_table = mmc35240_id, +}; + +module_i2c_driver(mmc35240_driver); + +MODULE_AUTHOR("Daniel Baluta <daniel.baluta@intel.com>"); +MODULE_DESCRIPTION("MEMSIC MMC35240 magnetic sensor driver"); +MODULE_LICENSE("GPL v2"); |