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path: root/drivers/iio/accel/mc3230.c
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Diffstat (limited to 'drivers/iio/accel/mc3230.c')
-rw-r--r--drivers/iio/accel/mc3230.c211
1 files changed, 211 insertions, 0 deletions
diff --git a/drivers/iio/accel/mc3230.c b/drivers/iio/accel/mc3230.c
new file mode 100644
index 000000000000..4ea2ff623a6d
--- /dev/null
+++ b/drivers/iio/accel/mc3230.c
@@ -0,0 +1,211 @@
+/**
+ * mCube MC3230 3-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 of the GNU General Public License as published by
+ * the Free Software Foundation; either version 2 of the License, or
+ * (at your option) any later version.
+ *
+ * IIO driver for mCube MC3230; 7-bit I2C address: 0x4c.
+ */
+
+#include <linux/i2c.h>
+#include <linux/module.h>
+#include <linux/iio/iio.h>
+#include <linux/iio/sysfs.h>
+
+#define MC3230_REG_XOUT 0x00
+#define MC3230_REG_YOUT 0x01
+#define MC3230_REG_ZOUT 0x02
+
+#define MC3230_REG_MODE 0x07
+#define MC3230_MODE_OPCON_MASK 0x03
+#define MC3230_MODE_OPCON_WAKE 0x01
+#define MC3230_MODE_OPCON_STANDBY 0x03
+
+#define MC3230_REG_CHIP_ID 0x18
+#define MC3230_CHIP_ID 0x01
+
+#define MC3230_REG_PRODUCT_CODE 0x3b
+#define MC3230_PRODUCT_CODE 0x19
+
+/*
+ * The accelerometer has one measurement range:
+ *
+ * -1.5g - +1.5g (8-bit, signed)
+ *
+ * scale = (1.5 + 1.5) * 9.81 / (2^8 - 1) = 0.115411765
+ */
+
+static const int mc3230_nscale = 115411765;
+
+#define MC3230_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 mc3230_channels[] = {
+ MC3230_CHANNEL(MC3230_REG_XOUT, X),
+ MC3230_CHANNEL(MC3230_REG_YOUT, Y),
+ MC3230_CHANNEL(MC3230_REG_ZOUT, Z),
+};
+
+struct mc3230_data {
+ struct i2c_client *client;
+};
+
+static int mc3230_set_opcon(struct mc3230_data *data, int opcon)
+{
+ int ret;
+ struct i2c_client *client = data->client;
+
+ ret = i2c_smbus_read_byte_data(client, MC3230_REG_MODE);
+ if (ret < 0) {
+ dev_err(&client->dev, "failed to read mode reg: %d\n", ret);
+ return ret;
+ }
+
+ ret &= ~MC3230_MODE_OPCON_MASK;
+ ret |= opcon;
+
+ ret = i2c_smbus_write_byte_data(client, MC3230_REG_MODE, ret);
+ if (ret < 0) {
+ dev_err(&client->dev, "failed to write mode reg: %d\n", ret);
+ return ret;
+ }
+
+ return 0;
+}
+
+static int mc3230_read_raw(struct iio_dev *indio_dev,
+ struct iio_chan_spec const *chan,
+ int *val, int *val2, long mask)
+{
+ struct mc3230_data *data = iio_priv(indio_dev);
+ int ret;
+
+ switch (mask) {
+ case IIO_CHAN_INFO_RAW:
+ ret = i2c_smbus_read_byte_data(data->client, chan->address);
+ if (ret < 0)
+ return ret;
+ *val = sign_extend32(ret, 7);
+ return IIO_VAL_INT;
+ case IIO_CHAN_INFO_SCALE:
+ *val = 0;
+ *val2 = mc3230_nscale;
+ return IIO_VAL_INT_PLUS_NANO;
+ default:
+ return -EINVAL;
+ }
+}
+
+static const struct iio_info mc3230_info = {
+ .driver_module = THIS_MODULE,
+ .read_raw = mc3230_read_raw,
+};
+
+static int mc3230_probe(struct i2c_client *client,
+ const struct i2c_device_id *id)
+{
+ int ret;
+ struct iio_dev *indio_dev;
+ struct mc3230_data *data;
+
+ /* First check chip-id and product-id */
+ ret = i2c_smbus_read_byte_data(client, MC3230_REG_CHIP_ID);
+ if (ret != MC3230_CHIP_ID)
+ return (ret < 0) ? ret : -ENODEV;
+
+ ret = i2c_smbus_read_byte_data(client, MC3230_REG_PRODUCT_CODE);
+ if (ret != MC3230_PRODUCT_CODE)
+ return (ret < 0) ? ret : -ENODEV;
+
+ 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;
+ i2c_set_clientdata(client, indio_dev);
+
+ indio_dev->dev.parent = &client->dev;
+ indio_dev->info = &mc3230_info;
+ indio_dev->name = "mc3230";
+ indio_dev->modes = INDIO_DIRECT_MODE;
+ indio_dev->channels = mc3230_channels;
+ indio_dev->num_channels = ARRAY_SIZE(mc3230_channels);
+
+ ret = mc3230_set_opcon(data, MC3230_MODE_OPCON_WAKE);
+ if (ret < 0)
+ return ret;
+
+ ret = iio_device_register(indio_dev);
+ if (ret < 0) {
+ dev_err(&client->dev, "device_register failed\n");
+ mc3230_set_opcon(data, MC3230_MODE_OPCON_STANDBY);
+ }
+
+ return ret;
+}
+
+static int mc3230_remove(struct i2c_client *client)
+{
+ struct iio_dev *indio_dev = i2c_get_clientdata(client);
+
+ iio_device_unregister(indio_dev);
+
+ return mc3230_set_opcon(iio_priv(indio_dev), MC3230_MODE_OPCON_STANDBY);
+}
+
+#ifdef CONFIG_PM_SLEEP
+static int mc3230_suspend(struct device *dev)
+{
+ struct mc3230_data *data;
+
+ data = iio_priv(i2c_get_clientdata(to_i2c_client(dev)));
+
+ return mc3230_set_opcon(data, MC3230_MODE_OPCON_STANDBY);
+}
+
+static int mc3230_resume(struct device *dev)
+{
+ struct mc3230_data *data;
+
+ data = iio_priv(i2c_get_clientdata(to_i2c_client(dev)));
+
+ return mc3230_set_opcon(data, MC3230_MODE_OPCON_WAKE);
+}
+#endif
+
+static SIMPLE_DEV_PM_OPS(mc3230_pm_ops, mc3230_suspend, mc3230_resume);
+
+static const struct i2c_device_id mc3230_i2c_id[] = {
+ {"mc3230", 0},
+ {}
+};
+MODULE_DEVICE_TABLE(i2c, mc3230_i2c_id);
+
+static struct i2c_driver mc3230_driver = {
+ .driver = {
+ .name = "mc3230",
+ .pm = &mc3230_pm_ops,
+ },
+ .probe = mc3230_probe,
+ .remove = mc3230_remove,
+ .id_table = mc3230_i2c_id,
+};
+
+module_i2c_driver(mc3230_driver);
+
+MODULE_AUTHOR("Hans de Goede <hdegoede@redhat.com>");
+MODULE_DESCRIPTION("mCube MC3230 3-Axis Accelerometer driver");
+MODULE_LICENSE("GPL v2");