iio: accel: Add driver for the MiraMEMS DA280 3-axis 14-bit digital accelerometer

Add an iio driver for the MiraMEMS DA280 3-axis 14-bit accelerometer, as
well as for the DA226 which is a fully compatible 2-axis version.

Datasheets for the DA280 and DA226 can be found at the manufacturers site:
http://www.miramems.com/en/products.asp?list=1

Signed-off-by: Hans de Goede <hdegoede@redhat.com>
Acked-by: Rob Herring <robh@kernel.org>
Signed-off-by: Jonathan Cameron <jic23@kernel.org>

diff --git a/Documentation/devicetree/bindings/i2c/trivial-devices.txt b/Documentation/devicetree/bindings/i2c/trivial-devices.txt
index decdd3e636bf076a0381998c0e4842d5ac3ce4f0..307f13bc81f23b0bdc3ce349b4d9fa431770c966 100644 (file)
--- a/Documentation/devicetree/bindings/i2c/trivial-devices.txt
+++ b/Documentation/devicetree/bindings/i2c/trivial-devices.txt
@@ -125,6 +125,8 @@ microchip,mcp4662-502       Microchip 8-bit Dual I2C Digital Potentiometer with NV Mem
 microchip,mcp4662-103  Microchip 8-bit Dual I2C Digital Potentiometer with NV Memory (10k)
 microchip,mcp4662-503  Microchip 8-bit Dual I2C Digital Potentiometer with NV Memory (50k)
 microchip,mcp4662-104  Microchip 8-bit Dual I2C Digital Potentiometer with NV Memory (100k)
+miramems,da226         MiraMEMS DA226 2-axis 14-bit digital accelerometer
+miramems,da280         MiraMEMS DA280 3-axis 14-bit digital accelerometer
 miramems,da311         MiraMEMS DA311 3-axis 12-bit digital accelerometer
 national,lm63          Temperature sensor with integrated fan control
 national,lm75          I2C TEMP SENSOR

diff --git a/drivers/iio/accel/Kconfig b/drivers/iio/accel/Kconfig
index 8945e70a797c83f0cee20990425ad21c721633e1..878e3c9449de6cd47da313eced71099a710df496 100644 (file)
--- a/drivers/iio/accel/Kconfig
+++ b/drivers/iio/accel/Kconfig
@@ -52,6 +52,16 @@ config BMC150_ACCEL_SPI
        tristate
        select REGMAP_SPI
 
+config DA280
+       tristate "MiraMEMS DA280 3-axis 14-bit digital accelerometer driver"
+       depends on I2C
+       help
+         Say yes here to build support for the MiraMEMS DA280 3-axis 14-bit
+         digital accelerometer.
+
+         To compile this driver as a module, choose M here: the
+         module will be called da280.
+
 config DA311
        tristate "MiraMEMS DA311 3-axis 12-bit digital accelerometer driver"
        depends on I2C

diff --git a/drivers/iio/accel/Makefile b/drivers/iio/accel/Makefile
index ade13ae5d056bd9b38e44bf774193507f7612758..0aa5749570471d1552cbd012a424d08fba173859 100644 (file)
--- a/drivers/iio/accel/Makefile
+++ b/drivers/iio/accel/Makefile
@@ -8,6 +8,7 @@ obj-$(CONFIG_BMA220) += bma220_spi.o
 obj-$(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-$(CONFIG_DA280)    += da280.o
 obj-$(CONFIG_DA311)    += da311.o
 obj-$(CONFIG_DMARD06)  += dmard06.o
 obj-$(CONFIG_DMARD09)  += dmard09.o

diff --git a/drivers/iio/accel/da280.c b/drivers/iio/accel/da280.c
new file mode 100644 (file)
index 0000000..ed8343a
--- /dev/null
+++ b/drivers/iio/accel/da280.c
@@ -0,0 +1,183 @@
+/**
+ * IIO driver for the MiraMEMS DA280 3-axis accelerometer and
+ * IIO driver for the MiraMEMS DA226 2-axis accelerometer
+ *
+ * Copyright (c) 2016 Hans de Goede <hdegoede@redhat.com>
+ *
+ * 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.
+ */
+
+#include <linux/module.h>
+#include <linux/i2c.h>
+#include <linux/iio/iio.h>
+#include <linux/iio/sysfs.h>
+#include <linux/byteorder/generic.h>
+
+#define DA280_REG_CHIP_ID              0x01
+#define DA280_REG_ACC_X_LSB            0x02
+#define DA280_REG_ACC_Y_LSB            0x04
+#define DA280_REG_ACC_Z_LSB            0x06
+#define DA280_REG_MODE_BW              0x11
+
+#define DA280_CHIP_ID                  0x13
+#define DA280_MODE_ENABLE              0x1e
+#define DA280_MODE_DISABLE             0x9e
+
+enum { da226, da280 };
+
+/*
+ * a value of + or -4096 corresponds to + or - 1G
+ * scale = 9.81 / 4096 = 0.002395019
+ */
+
+static const int da280_nscale = 2395019;
+
+#define DA280_CHANNEL(reg, axis) {     \
+       .type = IIO_ACCEL,      \
+       .address = reg, \
+       .modified = 1,  \
+       .channel2 = IIO_MOD_##axis,     \
+       .info_mask_separate = BIT(IIO_CHAN_INFO_RAW),   \
+       .info_mask_shared_by_type = BIT(IIO_CHAN_INFO_SCALE),   \
+}
+
+static const struct iio_chan_spec da280_channels[] = {
+       DA280_CHANNEL(DA280_REG_ACC_X_LSB, X),
+       DA280_CHANNEL(DA280_REG_ACC_Y_LSB, Y),
+       DA280_CHANNEL(DA280_REG_ACC_Z_LSB, Z),
+};
+
+struct da280_data {
+       struct i2c_client *client;
+};
+
+static int da280_enable(struct i2c_client *client, bool enable)
+{
+       u8 data = enable ? DA280_MODE_ENABLE : DA280_MODE_DISABLE;
+
+       return i2c_smbus_write_byte_data(client, DA280_REG_MODE_BW, data);
+}
+
+static int da280_read_raw(struct iio_dev *indio_dev,
+                               struct iio_chan_spec const *chan,
+                               int *val, int *val2, long mask)
+{
+       struct da280_data *data = iio_priv(indio_dev);
+       int ret;
+
+       switch (mask) {
+       case IIO_CHAN_INFO_RAW:
+               ret = i2c_smbus_read_word_data(data->client, chan->address);
+               if (ret < 0)
+                       return ret;
+               /*
+                * Values are 14 bits, stored as 16 bits with the 2
+                * least significant bits always 0.
+                */
+               *val = (short)ret >> 2;
+               return IIO_VAL_INT;
+       case IIO_CHAN_INFO_SCALE:
+               *val = 0;
+               *val2 = da280_nscale;
+               return IIO_VAL_INT_PLUS_NANO;
+       default:
+               return -EINVAL;
+       }
+}
+
+static const struct iio_info da280_info = {
+       .driver_module  = THIS_MODULE,
+       .read_raw       = da280_read_raw,
+};
+
+static int da280_probe(struct i2c_client *client,
+                       const struct i2c_device_id *id)
+{
+       int ret;
+       struct iio_dev *indio_dev;
+       struct da280_data *data;
+
+       ret = i2c_smbus_read_byte_data(client, DA280_REG_CHIP_ID);
+       if (ret != DA280_CHIP_ID)
+               return (ret < 0) ? ret : -ENODEV;
+
+       indio_dev = devm_iio_device_alloc(&client->dev, sizeof(*data));
+       if (!indio_dev)
+               return -ENOMEM;
+
+       data = iio_priv(indio_dev);
+       data->client = client;
+       i2c_set_clientdata(client, indio_dev);
+
+       indio_dev->dev.parent = &client->dev;
+       indio_dev->info = &da280_info;
+       indio_dev->modes = INDIO_DIRECT_MODE;
+       indio_dev->channels = da280_channels;
+       if (id->driver_data == da226) {
+               indio_dev->name = "da226";
+               indio_dev->num_channels = 2;
+       } else {
+               indio_dev->name = "da280";
+               indio_dev->num_channels = 3;
+       }
+
+       ret = da280_enable(client, true);
+       if (ret < 0)
+               return ret;
+
+       ret = iio_device_register(indio_dev);
+       if (ret < 0) {
+               dev_err(&client->dev, "device_register failed\n");
+               da280_enable(client, false);
+       }
+
+       return ret;
+}
+
+static int da280_remove(struct i2c_client *client)
+{
+       struct iio_dev *indio_dev = i2c_get_clientdata(client);
+
+       iio_device_unregister(indio_dev);
+
+       return da280_enable(client, false);
+}
+
+#ifdef CONFIG_PM_SLEEP
+static int da280_suspend(struct device *dev)
+{
+       return da280_enable(to_i2c_client(dev), false);
+}
+
+static int da280_resume(struct device *dev)
+{
+       return da280_enable(to_i2c_client(dev), true);
+}
+#endif
+
+static SIMPLE_DEV_PM_OPS(da280_pm_ops, da280_suspend, da280_resume);
+
+static const struct i2c_device_id da280_i2c_id[] = {
+       { "da226", da226 },
+       { "da280", da280 },
+       {}
+};
+MODULE_DEVICE_TABLE(i2c, da280_i2c_id);
+
+static struct i2c_driver da280_driver = {
+       .driver = {
+               .name = "da280",
+               .pm = &da280_pm_ops,
+       },
+       .probe          = da280_probe,
+       .remove         = da280_remove,
+       .id_table       = da280_i2c_id,
+};
+
+module_i2c_driver(da280_driver);
+
+MODULE_AUTHOR("Hans de Goede <hdegoede@redhat.com>");
+MODULE_DESCRIPTION("MiraMEMS DA280 3-Axis Accelerometer driver");
+MODULE_LICENSE("GPL v2");