From 077377fc4f74899c58e946e47352216412d0bb3a Mon Sep 17 00:00:00 2001 From: Teodora Baluta Date: Thu, 20 Aug 2015 17:37:31 +0300 Subject: [PATCH] iio: accel: add support for mxc4005 accelerometer This patch adds support for Memsic MXC4005XC 3-axis accelerometer. The current implementation is a minimal one as it adds raw readings for the three axes and setting scale from userspace. Signed-off-by: Teodora Baluta Signed-off-by: Jonathan Cameron --- drivers/iio/accel/Kconfig | 11 ++ drivers/iio/accel/Makefile | 2 + drivers/iio/accel/mxc4005.c | 354 ++++++++++++++++++++++++++++++++++++ 3 files changed, 367 insertions(+) create mode 100644 drivers/iio/accel/mxc4005.c diff --git a/drivers/iio/accel/Kconfig b/drivers/iio/accel/Kconfig index a59047d7657e..69302bed2860 100644 --- a/drivers/iio/accel/Kconfig +++ b/drivers/iio/accel/Kconfig @@ -137,6 +137,17 @@ config MMA9553 To compile this driver as a module, choose M here: the module will be called mma9553. +config MXC4005 + tristate "Memsic MXC4005XC 3-Axis Accelerometer Driver" + depends on I2C + select REGMAP_I2C + help + Say yes here to build support for the Memsic MXC4005XC 3-axis + accelerometer. + + To compile this driver as a module, choose M. The module will be + called mxc4005. + config STK8312 tristate "Sensortek STK8312 3-Axis Accelerometer Driver" depends on I2C diff --git a/drivers/iio/accel/Makefile b/drivers/iio/accel/Makefile index ebd2675b2a02..020dda0ae508 100644 --- a/drivers/iio/accel/Makefile +++ b/drivers/iio/accel/Makefile @@ -14,6 +14,8 @@ obj-$(CONFIG_MMA9551_CORE) += mma9551_core.o obj-$(CONFIG_MMA9551) += mma9551.o obj-$(CONFIG_MMA9553) += mma9553.o +obj-$(CONFIG_MXC4005) += mxc4005.o + obj-$(CONFIG_STK8312) += stk8312.o obj-$(CONFIG_STK8BA50) += stk8ba50.o diff --git a/drivers/iio/accel/mxc4005.c b/drivers/iio/accel/mxc4005.c new file mode 100644 index 000000000000..e15c1bd26bd1 --- /dev/null +++ b/drivers/iio/accel/mxc4005.c @@ -0,0 +1,354 @@ +/* + * 3-axis accelerometer driver for MXC4005XC Memsic sensor + * + * Copyright (c) 2014, Intel Corporation. + * + * This program is free software; you can redistribute it and/or modify it + * under the terms and conditions of the GNU General Public License, + * version 2, as published by the Free Software Foundation. + * + * This program is distributed in the hope it will be useful, but WITHOUT + * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or + * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License for + * more details. + */ + +#include +#include +#include +#include +#include +#include + +#define MXC4005_DRV_NAME "mxc4005" +#define MXC4005_REGMAP_NAME "mxc4005_regmap" + +#define MXC4005_REG_XOUT_UPPER 0x03 +#define MXC4005_REG_XOUT_LOWER 0x04 +#define MXC4005_REG_YOUT_UPPER 0x05 +#define MXC4005_REG_YOUT_LOWER 0x06 +#define MXC4005_REG_ZOUT_UPPER 0x07 +#define MXC4005_REG_ZOUT_LOWER 0x08 + +#define MXC4005_REG_CONTROL 0x0D +#define MXC4005_REG_CONTROL_MASK_FSR GENMASK(6, 5) +#define MXC4005_CONTROL_FSR_SHIFT 5 + +#define MXC4005_REG_DEVICE_ID 0x0E + +enum mxc4005_axis { + AXIS_X, + AXIS_Y, + AXIS_Z, +}; + +enum mxc4005_range { + MXC4005_RANGE_2G, + MXC4005_RANGE_4G, + MXC4005_RANGE_8G, +}; + +struct mxc4005_data { + struct device *dev; + struct mutex mutex; + struct regmap *regmap; +}; + +/* + * MXC4005 can operate in the following ranges: + * +/- 2G, 4G, 8G (the default +/-2G) + * + * (2 + 2) * 9.81 / (2^12 - 1) = 0.009582 + * (4 + 4) * 9.81 / (2^12 - 1) = 0.019164 + * (8 + 8) * 9.81 / (2^12 - 1) = 0.038329 + */ +static const struct { + u8 range; + int scale; +} mxc4005_scale_table[] = { + {MXC4005_RANGE_2G, 9582}, + {MXC4005_RANGE_4G, 19164}, + {MXC4005_RANGE_8G, 38329}, +}; + + +static IIO_CONST_ATTR(in_accel_scale_available, "0.009582 0.019164 0.038329"); + +static struct attribute *mxc4005_attributes[] = { + &iio_const_attr_in_accel_scale_available.dev_attr.attr, + NULL, +}; + +static const struct attribute_group mxc4005_attrs_group = { + .attrs = mxc4005_attributes, +}; + +static bool mxc4005_is_readable_reg(struct device *dev, unsigned int reg) +{ + switch (reg) { + case MXC4005_REG_XOUT_UPPER: + case MXC4005_REG_XOUT_LOWER: + case MXC4005_REG_YOUT_UPPER: + case MXC4005_REG_YOUT_LOWER: + case MXC4005_REG_ZOUT_UPPER: + case MXC4005_REG_ZOUT_LOWER: + case MXC4005_REG_DEVICE_ID: + case MXC4005_REG_CONTROL: + return true; + default: + return false; + } +} + +static bool mxc4005_is_writeable_reg(struct device *dev, unsigned int reg) +{ + switch (reg) { + case MXC4005_REG_CONTROL: + return true; + default: + return false; + } +} + +static const struct regmap_config mxc4005_regmap_config = { + .name = MXC4005_REGMAP_NAME, + + .reg_bits = 8, + .val_bits = 8, + + .max_register = MXC4005_REG_DEVICE_ID, + + .readable_reg = mxc4005_is_readable_reg, + .writeable_reg = mxc4005_is_writeable_reg, +}; + +static int mxc4005_read_axis(struct mxc4005_data *data, + unsigned int addr) +{ + __be16 reg; + int ret; + + ret = regmap_bulk_read(data->regmap, addr, (u8 *) ®, sizeof(reg)); + if (ret < 0) { + dev_err(data->dev, "failed to read reg %02x\n", addr); + return ret; + } + + return be16_to_cpu(reg); +} + +static int mxc4005_read_scale(struct mxc4005_data *data) +{ + unsigned int reg; + int ret; + int i; + + ret = regmap_read(data->regmap, MXC4005_REG_CONTROL, ®); + if (ret < 0) { + dev_err(data->dev, "failed to read reg_control\n"); + return ret; + } + + i = reg >> MXC4005_CONTROL_FSR_SHIFT; + + if (i < 0 || i >= ARRAY_SIZE(mxc4005_scale_table)) + return -EINVAL; + + return mxc4005_scale_table[i].scale; +} + +static int mxc4005_set_scale(struct mxc4005_data *data, int val) +{ + unsigned int reg; + int i; + int ret; + + for (i = 0; i < ARRAY_SIZE(mxc4005_scale_table); i++) { + if (mxc4005_scale_table[i].scale == val) { + reg = i << MXC4005_CONTROL_FSR_SHIFT; + ret = regmap_update_bits(data->regmap, + MXC4005_REG_CONTROL, + MXC4005_REG_CONTROL_MASK_FSR, + reg); + if (ret < 0) + dev_err(data->dev, + "failed to write reg_control\n"); + return ret; + } + } + + return -EINVAL; +} + +static int mxc4005_read_raw(struct iio_dev *indio_dev, + struct iio_chan_spec const *chan, + int *val, int *val2, long mask) +{ + struct mxc4005_data *data = iio_priv(indio_dev); + int ret; + + switch (mask) { + case IIO_CHAN_INFO_RAW: + switch (chan->type) { + case IIO_ACCEL: + if (iio_buffer_enabled(indio_dev)) + return -EBUSY; + + ret = mxc4005_read_axis(data, chan->address); + if (ret < 0) + return ret; + *val = sign_extend32(ret >> 4, 11); + return IIO_VAL_INT; + default: + return -EINVAL; + } + case IIO_CHAN_INFO_SCALE: + ret = mxc4005_read_scale(data); + if (ret < 0) + return ret; + + *val = 0; + *val2 = ret; + return IIO_VAL_INT_PLUS_MICRO; + default: + return -EINVAL; + } +} + +static int mxc4005_write_raw(struct iio_dev *indio_dev, + struct iio_chan_spec const *chan, + int val, int val2, long mask) +{ + struct mxc4005_data *data = iio_priv(indio_dev); + + switch (mask) { + case IIO_CHAN_INFO_SCALE: + if (val != 0) + return -EINVAL; + + return mxc4005_set_scale(data, val2); + default: + return -EINVAL; + } +} + +static const struct iio_info mxc4005_info = { + .driver_module = THIS_MODULE, + .read_raw = mxc4005_read_raw, + .write_raw = mxc4005_write_raw, + .attrs = &mxc4005_attrs_group, +}; + +#define MXC4005_CHANNEL(_axis, _addr) { \ + .type = IIO_ACCEL, \ + .modified = 1, \ + .channel2 = IIO_MOD_##_axis, \ + .address = _addr, \ + .info_mask_separate = BIT(IIO_CHAN_INFO_RAW), \ + .info_mask_shared_by_type = BIT(IIO_CHAN_INFO_SCALE), \ +} + +static const struct iio_chan_spec mxc4005_channels[] = { + MXC4005_CHANNEL(X, MXC4005_REG_XOUT_UPPER), + MXC4005_CHANNEL(Y, MXC4005_REG_YOUT_UPPER), + MXC4005_CHANNEL(Z, MXC4005_REG_ZOUT_UPPER), +}; + +static int mxc4005_chip_init(struct mxc4005_data *data) +{ + int ret; + unsigned int reg; + + ret = regmap_read(data->regmap, MXC4005_REG_DEVICE_ID, ®); + if (ret < 0) { + dev_err(data->dev, "failed to read chip id\n"); + return ret; + } + + dev_dbg(data->dev, "MXC4005 chip id %02x\n", reg); + + return 0; +} + +static int mxc4005_probe(struct i2c_client *client, + const struct i2c_device_id *id) +{ + struct mxc4005_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, &mxc4005_regmap_config); + if (IS_ERR(regmap)) { + dev_err(&client->dev, "failed to initialize regmap\n"); + return PTR_ERR(regmap); + } + + data = iio_priv(indio_dev); + i2c_set_clientdata(client, indio_dev); + data->dev = &client->dev; + data->regmap = regmap; + + ret = mxc4005_chip_init(data); + if (ret < 0) { + dev_err(&client->dev, "failed to initialize chip\n"); + return ret; + } + + mutex_init(&data->mutex); + + indio_dev->dev.parent = &client->dev; + indio_dev->channels = mxc4005_channels; + indio_dev->num_channels = ARRAY_SIZE(mxc4005_channels); + indio_dev->name = MXC4005_DRV_NAME; + indio_dev->modes = INDIO_DIRECT_MODE; + indio_dev->info = &mxc4005_info; + + ret = iio_device_register(indio_dev); + if (ret < 0) { + dev_err(&client->dev, + "unable to register iio device %d\n", ret); + return ret; + } + + return 0; +} + +static int mxc4005_remove(struct i2c_client *client) +{ + iio_device_unregister(i2c_get_clientdata(client)); + + return 0; +} + +static const struct acpi_device_id mxc4005_acpi_match[] = { + {"MXC4005", 0}, + { }, +}; +MODULE_DEVICE_TABLE(acpi, mxc4005_acpi_match); + +static const struct i2c_device_id mxc4005_id[] = { + {"mxc4005", 0}, + { }, +}; +MODULE_DEVICE_TABLE(i2c, mxc4005_id); + +static struct i2c_driver mxc4005_driver = { + .driver = { + .name = MXC4005_DRV_NAME, + .acpi_match_table = ACPI_PTR(mxc4005_acpi_match), + }, + .probe = mxc4005_probe, + .remove = mxc4005_remove, + .id_table = mxc4005_id, +}; + +module_i2c_driver(mxc4005_driver); + +MODULE_AUTHOR("Teodora Baluta "); +MODULE_LICENSE("GPL v2"); +MODULE_DESCRIPTION("MXC4005 3-axis accelerometer driver"); -- 2.30.2