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Diffstat (limited to 'drivers/iio/common/st_sensors/st_sensors_i2c.c')
-rw-r--r--drivers/iio/common/st_sensors/st_sensors_i2c.c112
1 files changed, 112 insertions, 0 deletions
diff --git a/drivers/iio/common/st_sensors/st_sensors_i2c.c b/drivers/iio/common/st_sensors/st_sensors_i2c.c
new file mode 100644
index 000000000..98cfee296
--- /dev/null
+++ b/drivers/iio/common/st_sensors/st_sensors_i2c.c
@@ -0,0 +1,112 @@
+/*
+ * STMicroelectronics sensors i2c library driver
+ *
+ * Copyright 2012-2013 STMicroelectronics Inc.
+ *
+ * Denis Ciocca <denis.ciocca@st.com>
+ *
+ * Licensed under the GPL-2.
+ */
+
+#include <linux/kernel.h>
+#include <linux/module.h>
+#include <linux/slab.h>
+#include <linux/iio/iio.h>
+#include <linux/of_device.h>
+
+#include <linux/iio/common/st_sensors_i2c.h>
+
+
+#define ST_SENSORS_I2C_MULTIREAD 0x80
+
+static unsigned int st_sensors_i2c_get_irq(struct iio_dev *indio_dev)
+{
+ struct st_sensor_data *sdata = iio_priv(indio_dev);
+
+ return to_i2c_client(sdata->dev)->irq;
+}
+
+static int st_sensors_i2c_read_byte(struct st_sensor_transfer_buffer *tb,
+ struct device *dev, u8 reg_addr, u8 *res_byte)
+{
+ int err;
+
+ err = i2c_smbus_read_byte_data(to_i2c_client(dev), reg_addr);
+ if (err < 0)
+ goto st_accel_i2c_read_byte_error;
+
+ *res_byte = err & 0xff;
+
+st_accel_i2c_read_byte_error:
+ return err < 0 ? err : 0;
+}
+
+static int st_sensors_i2c_read_multiple_byte(
+ struct st_sensor_transfer_buffer *tb, struct device *dev,
+ u8 reg_addr, int len, u8 *data, bool multiread_bit)
+{
+ if (multiread_bit)
+ reg_addr |= ST_SENSORS_I2C_MULTIREAD;
+
+ return i2c_smbus_read_i2c_block_data(to_i2c_client(dev),
+ reg_addr, len, data);
+}
+
+static int st_sensors_i2c_write_byte(struct st_sensor_transfer_buffer *tb,
+ struct device *dev, u8 reg_addr, u8 data)
+{
+ return i2c_smbus_write_byte_data(to_i2c_client(dev), reg_addr, data);
+}
+
+static const struct st_sensor_transfer_function st_sensors_tf_i2c = {
+ .read_byte = st_sensors_i2c_read_byte,
+ .write_byte = st_sensors_i2c_write_byte,
+ .read_multiple_byte = st_sensors_i2c_read_multiple_byte,
+};
+
+void st_sensors_i2c_configure(struct iio_dev *indio_dev,
+ struct i2c_client *client, struct st_sensor_data *sdata)
+{
+ i2c_set_clientdata(client, indio_dev);
+
+ indio_dev->dev.parent = &client->dev;
+ indio_dev->name = client->name;
+
+ sdata->dev = &client->dev;
+ sdata->tf = &st_sensors_tf_i2c;
+ sdata->get_irq_data_ready = st_sensors_i2c_get_irq;
+}
+EXPORT_SYMBOL(st_sensors_i2c_configure);
+
+#ifdef CONFIG_OF
+/**
+ * st_sensors_of_i2c_probe() - device tree probe for ST I2C sensors
+ * @client: the I2C client device for the sensor
+ * @match: the OF match table for the device, containing compatible strings
+ * but also a .data field with the corresponding internal kernel name
+ * used by this sensor.
+ *
+ * In effect this function matches a compatible string to an internal kernel
+ * name for a certain sensor device, so that the rest of the autodetection can
+ * rely on that name from this point on. I2C client devices will be renamed
+ * to match the internal kernel convention.
+ */
+void st_sensors_of_i2c_probe(struct i2c_client *client,
+ const struct of_device_id *match)
+{
+ const struct of_device_id *of_id;
+
+ of_id = of_match_device(match, &client->dev);
+ if (!of_id)
+ return;
+
+ /* The name from the OF match takes precedence if present */
+ strncpy(client->name, of_id->data, sizeof(client->name));
+ client->name[sizeof(client->name) - 1] = '\0';
+}
+EXPORT_SYMBOL(st_sensors_of_i2c_probe);
+#endif
+
+MODULE_AUTHOR("Denis Ciocca <denis.ciocca@st.com>");
+MODULE_DESCRIPTION("STMicroelectronics ST-sensors i2c driver");
+MODULE_LICENSE("GPL v2");