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-rw-r--r--drivers/iio/accel/da280.c195
1 files changed, 195 insertions, 0 deletions
diff --git a/drivers/iio/accel/da280.c b/drivers/iio/accel/da280.c
new file mode 100644
index 000000000..04e9c5678
--- /dev/null
+++ b/drivers/iio/accel/da280.c
@@ -0,0 +1,195 @@
+// SPDX-License-Identifier: GPL-2.0-only
+/*
+ * 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>
+ */
+
+#include <linux/module.h>
+#include <linux/i2c.h>
+#include <linux/acpi.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 da280_chipset { 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 = {
+ .read_raw = da280_read_raw,
+};
+
+static enum da280_chipset da280_match_acpi_device(struct device *dev)
+{
+ const struct acpi_device_id *id;
+
+ id = acpi_match_device(dev->driver->acpi_match_table, dev);
+ if (!id)
+ return -EINVAL;
+
+ return (enum da280_chipset) id->driver_data;
+}
+
+static void da280_disable(void *client)
+{
+ da280_enable(client, false);
+}
+
+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;
+ enum da280_chipset chip;
+
+ 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;
+
+ indio_dev->info = &da280_info;
+ indio_dev->modes = INDIO_DIRECT_MODE;
+ indio_dev->channels = da280_channels;
+
+ if (ACPI_HANDLE(&client->dev)) {
+ chip = da280_match_acpi_device(&client->dev);
+ } else {
+ chip = id->driver_data;
+ }
+
+ if (chip == 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 = devm_add_action_or_reset(&client->dev, da280_disable, client);
+ if (ret)
+ return ret;
+
+ return devm_iio_device_register(&client->dev, indio_dev);
+}
+
+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);
+}
+
+static DEFINE_SIMPLE_DEV_PM_OPS(da280_pm_ops, da280_suspend, da280_resume);
+
+static const struct acpi_device_id da280_acpi_match[] = {
+ {"MIRAACC", da280},
+ {},
+};
+MODULE_DEVICE_TABLE(acpi, da280_acpi_match);
+
+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",
+ .acpi_match_table = ACPI_PTR(da280_acpi_match),
+ .pm = pm_sleep_ptr(&da280_pm_ops),
+ },
+ .probe = da280_probe,
+ .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");