[PATCH 3/3] iio: imu: inv_mpu6050: Add basic support for mpu9150

[Manuel Stahl <manuel.stahl@iis.fraunhofer.de>]

The magnetometer included in the mpu9150 will be exported to the
I2C bus at address 0x0C and can be accessed by the IIO driver
ak8975.

Signed-off-by: Manuel Stahl <manuel.stahl@iis.fraunhofer.de>
---
 drivers/iio/imu/inv_mpu6050/Kconfig        |  6 ++++--
 drivers/iio/imu/inv_mpu6050/inv_mpu_core.c | 21 ++++++++++++++++++++-
 drivers/iio/imu/inv_mpu6050/inv_mpu_iio.h  |  4 ++++
 3 files changed, 28 insertions(+), 3 deletions(-)

diff --git a/drivers/iio/imu/inv_mpu6050/Kconfig b/drivers/iio/imu/inv_mpu6050/Kconfig
index 361b232..9843f9e 100644
--- a/drivers/iio/imu/inv_mpu6050/Kconfig
+++ b/drivers/iio/imu/inv_mpu6050/Kconfig
@@ -3,12 +3,14 @@
 #
 
 config INV_MPU6050_IIO
-	tristate "Invensense MPU6050 devices"
+	tristate "Invensense MPU6050 and MPU9150 devices"
 	depends on I2C && SYSFS
 	select IIO_BUFFER
 	select IIO_TRIGGERED_BUFFER
 	help
-	  This driver supports the Invensense MPU6050 devices.
+	  This driver supports the Invensense MPU6050 and MPU9150 devices.
 	  It is a gyroscope/accelerometer combo device.
+	  The MPU9150 has an additional magnetometer, but this is currently
+	  only exported as a separate device on I2C address 0x0C.
 	  This driver can be built as a module. The module will be called
 	  inv-mpu6050.
diff --git a/drivers/iio/imu/inv_mpu6050/inv_mpu_core.c b/drivers/iio/imu/inv_mpu6050/inv_mpu_core.c
index fda1ee2..a121b5c 100644
--- a/drivers/iio/imu/inv_mpu6050/inv_mpu_core.c
+++ b/drivers/iio/imu/inv_mpu6050/inv_mpu_core.c
@@ -71,6 +71,12 @@ static const struct inv_mpu6050_hw hw_info[INV_NUM_PARTS] = {
 		.reg = &reg_set_6050,
 		.config = &chip_config_6050,
 	},
+	{
+		.num_reg = 118,
+		.name = "MPU9150",
+		.reg = &reg_set_6050,
+		.config = &chip_config_6050,
+	},
 };
 
 int inv_mpu6050_write_reg(struct inv_mpu6050_state *st, int reg, u8 d)
@@ -616,7 +622,12 @@ static int inv_check_and_setup_chip(struct inv_mpu6050_state *st,
 {
 	int result;
 
-	st->chip_type = INV_MPU6050;
+	st->chip_type = (unsigned)id->driver_data;
+	if (st->chip_type >= INV_NUM_PARTS) {
+		dev_err(&st->client->dev,
+			"Invalid chip type: %s.\n", id->name);
+		return -ENODEV;
+	}
 	st->hw  = &hw_info[st->chip_type];
 	st->reg = hw_info[st->chip_type].reg;
 
@@ -646,6 +657,11 @@ static int inv_check_and_setup_chip(struct inv_mpu6050_state *st,
 	if (result)
 		return result;
 
+	/* set to bypass mode */
+	result = inv_mpu6050_write_reg(st, INV_MPU6050_REG_INT_PIN_CFG,
+			INV_MPU6050_BIT_BYPASS_EN);
+	if (result)
+		return result;
 	return 0;
 }
 
@@ -719,6 +735,8 @@ static int inv_mpu_probe(struct i2c_client *client,
 		goto out_remove_trigger;
 	}
 
+	dev_info(&st->client->dev, "IMU %s found\n", id->name);
+
 	return 0;
 
 out_remove_trigger:
@@ -765,6 +783,7 @@ static SIMPLE_DEV_PM_OPS(inv_mpu_pmops, inv_mpu_suspend, inv_mpu_resume);
  */
 static const struct i2c_device_id inv_mpu_id[] = {
 	{"mpu6050", INV_MPU6050},
+	{"mpu9150", INV_MPU9150},
 	{}
 };
 
diff --git a/drivers/iio/imu/inv_mpu6050/inv_mpu_iio.h b/drivers/iio/imu/inv_mpu6050/inv_mpu_iio.h
index 0ab382b..d91b1e4 100644
--- a/drivers/iio/imu/inv_mpu6050/inv_mpu_iio.h
+++ b/drivers/iio/imu/inv_mpu6050/inv_mpu_iio.h
@@ -59,6 +59,7 @@ struct inv_mpu6050_reg_map {
 /*device enum */
 enum inv_devices {
 	INV_MPU6050,
+	INV_MPU9150,
 	INV_NUM_PARTS
 };
 
@@ -132,6 +133,9 @@ struct inv_mpu6050_state {
 #define INV_MPU6050_BIT_ACCEL_OUT           0x08
 #define INV_MPU6050_BITS_GYRO_OUT           0x70
 
+#define INV_MPU6050_REG_INT_PIN_CFG         0x37
+#define INV_MPU6050_BIT_BYPASS_EN           0x02
+
 #define INV_MPU6050_REG_INT_ENABLE          0x38
 #define INV_MPU6050_BIT_DATA_RDY_EN         0x01
 #define INV_MPU6050_BIT_DMP_INT_EN          0x02
-- 
1.8.3.2