iio: accel: add support for the Domintech DMARD09 3-axis accelerometer (a4fa6509) · Commits · jan.koester / Linux

Documentation/devicetree/bindings/i2c/trivial-devices.txt

+1 −0

Original line number	Diff line number	Diff line
		@@ -38,6 +38,7 @@ dallas,ds4510 CPU Supervisor with Nonvolatile Memory and Programmable I/O
		dallas,ds75 Digital Thermometer and Thermostat
		dlg,da9053 DA9053: flexible system level PMIC with multicore support
		dlg,da9063 DA9063: system PMIC for quad-core application processors
		domintech,dmard09 DMARD09: 3-axis Accelerometer
		epson,rx8010 I2C-BUS INTERFACE REAL TIME CLOCK MODULE
		epson,rx8025 High-Stability. I2C-Bus INTERFACE REAL TIME CLOCK MODULE
		epson,rx8581 I2C-BUS INTERFACE REAL TIME CLOCK MODULE

drivers/iio/accel/Kconfig

+10 −0

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		@@ -61,6 +61,16 @@ config DMARD06
		To compile this driver as a module, choose M here: the
		module will be called dmard06.

		config DMARD09
		tristate "Domintech DMARD09 3-axis Accelerometer Driver"
		depends on I2C
		help
		Say yes here to get support for the Domintech DMARD09 3-axis
		accelerometer.

		Choosing M will build the driver as a module. If so, the module
		will be called dmard09.

		config HID_SENSOR_ACCEL_3D
		depends on HID_SENSOR_HUB
		select IIO_BUFFER

drivers/iio/accel/Makefile

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		@@ -9,6 +9,7 @@ obj-$(CONFIG_BMC150_ACCEL) += bmc150-accel-core.o
		obj-$(CONFIG_BMC150_ACCEL_I2C) += bmc150-accel-i2c.o
		obj-$(CONFIG_BMC150_ACCEL_SPI) += bmc150-accel-spi.o
		obj-$(CONFIG_DMARD06) += dmard06.o
		obj-$(CONFIG_DMARD09) += dmard09.o
		obj-$(CONFIG_HID_SENSOR_ACCEL_3D) += hid-sensor-accel-3d.o
		obj-$(CONFIG_KXCJK1013) += kxcjk-1013.o
		obj-$(CONFIG_KXSD9) += kxsd9.o

drivers/iio/accel/dmard09.c

0 → 100644

+157 −0

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		/*
		* IIO driver for the 3-axis accelerometer Domintech DMARD09.
		*
		* Copyright (c) 2016, Jelle van der Waa <jelle@vdwaa.nl>
		*
		* 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 <asm/unaligned.h>
		#include <linux/module.h>
		#include <linux/i2c.h>
		#include <linux/iio/iio.h>

		#define DMARD09_DRV_NAME "dmard09"

		#define DMARD09_REG_CHIPID 0x18
		#define DMARD09_REG_STAT 0x0A
		#define DMARD09_REG_X 0x0C
		#define DMARD09_REG_Y 0x0E
		#define DMARD09_REG_Z 0x10
		#define DMARD09_CHIPID 0x95

		#define DMARD09_BUF_LEN 8
		#define DMARD09_AXIS_X 0
		#define DMARD09_AXIS_Y 1
		#define DMARD09_AXIS_Z 2
		#define DMARD09_AXIS_X_OFFSET ((DMARD09_AXIS_X + 1) * 2)
		#define DMARD09_AXIS_Y_OFFSET ((DMARD09_AXIS_Y + 1 )* 2)
		#define DMARD09_AXIS_Z_OFFSET ((DMARD09_AXIS_Z + 1) * 2)

		struct dmard09_data {
		struct i2c_client *client;
		};

		#define DMARD09_CHANNEL(_axis, offset) { \
		.type = IIO_ACCEL, \
		.info_mask_separate = BIT(IIO_CHAN_INFO_RAW), \
		.info_mask_shared_by_type = BIT(IIO_CHAN_INFO_SCALE), \
		.modified = 1, \
		.address = offset, \
		.channel2 = IIO_MOD_##_axis, \
		}

		static const struct iio_chan_spec dmard09_channels[] = {
		DMARD09_CHANNEL(X, DMARD09_AXIS_X_OFFSET),
		DMARD09_CHANNEL(Y, DMARD09_AXIS_Y_OFFSET),
		DMARD09_CHANNEL(Z, DMARD09_AXIS_Z_OFFSET),
		};

		static int dmard09_read_raw(struct iio_dev *indio_dev,
		struct iio_chan_spec const *chan,
		int val, int val2, long mask)
		{
		struct dmard09_data *data = iio_priv(indio_dev);
		u8 buf[DMARD09_BUF_LEN];
		int ret;
		s16 accel;

		switch (mask) {
		case IIO_CHAN_INFO_RAW:
		/*
		* Read from the DMAR09_REG_STAT register, since the chip
		* caches reads from the individual X, Y, Z registers.
		*/
		ret = i2c_smbus_read_i2c_block_data(data->client,
		DMARD09_REG_STAT,
		DMARD09_BUF_LEN, buf);
		if (ret < 0) {
		dev_err(&data->client->dev, "Error reading reg %d\n",
		DMARD09_REG_STAT);
		return ret;
		}

		accel = get_unaligned_le16(&buf[chan->address]);

		/* Remove lower 3 bits and sign extend */
		accel <<= 4;
		accel >>= 7;

		*val = accel;

		return IIO_VAL_INT;
		default:
		return -EINVAL;
		}
		}

		static const struct iio_info dmard09_info = {
		.driver_module = THIS_MODULE,
		.read_raw = dmard09_read_raw,
		};

		static int dmard09_probe(struct i2c_client *client,
		const struct i2c_device_id *id)
		{
		int ret;
		struct iio_dev *indio_dev;
		struct dmard09_data *data;

		indio_dev = devm_iio_device_alloc(&client->dev, sizeof(*data));
		if (!indio_dev) {
		dev_err(&client->dev, "iio allocation failed\n");
		return -ENOMEM;
		}

		data = iio_priv(indio_dev);
		data->client = client;

		ret = i2c_smbus_read_byte_data(data->client, DMARD09_REG_CHIPID);
		if (ret < 0) {
		dev_err(&client->dev, "Error reading chip id %d\n", ret);
		return ret;
		}

		if (ret != DMARD09_CHIPID) {
		dev_err(&client->dev, "Invalid chip id %d\n", ret);
		return -ENODEV;
		}

		i2c_set_clientdata(client, indio_dev);
		indio_dev->dev.parent = &client->dev;
		indio_dev->name = DMARD09_DRV_NAME;
		indio_dev->modes = INDIO_DIRECT_MODE;
		indio_dev->channels = dmard09_channels;
		indio_dev->num_channels = ARRAY_SIZE(dmard09_channels);
		indio_dev->info = &dmard09_info;

		return devm_iio_device_register(&client->dev, indio_dev);
		}

		static const struct i2c_device_id dmard09_id[] = {
		{ "dmard09", 0},
		{ },
		};

		MODULE_DEVICE_TABLE(i2c, dmard09_id);

		static struct i2c_driver dmard09_driver = {
		.driver = {
		.name = DMARD09_DRV_NAME
		},
		.probe = dmard09_probe,
		.id_table = dmard09_id,
		};

		module_i2c_driver(dmard09_driver);

		MODULE_AUTHOR("Jelle van der Waa <jelle@vdwaa.nl>");
		MODULE_DESCRIPTION("DMARD09 3-axis accelerometer driver");
		MODULE_LICENSE("GPL");