diff options
| author | Crestez Dan Leonard <leonard.crestez@intel.com> | 2016-04-20 16:15:11 +0300 |
|---|---|---|
| committer | Jonathan Cameron <jic23@kernel.org> | 2016-04-25 20:19:15 +0100 |
| commit | cec0154556f8fe6d3a7f5d370f715283888d1c02 (patch) | |
| tree | 7a082b20a86aee92d75492aaf804d5d5dafc0764 /drivers | |
| parent | 7bdd3181596d3d95ef39849bc3ef8e5b91cb6ae1 (diff) | |
| download | linux-cec0154556f8fe6d3a7f5d370f715283888d1c02.tar.gz linux-cec0154556f8fe6d3a7f5d370f715283888d1c02.tar.bz2 linux-cec0154556f8fe6d3a7f5d370f715283888d1c02.zip | |
iio: inv_mpu6050: Check WHO_AM_I register on probe
This can be used to distinguish mpu6500. This is a warning rather than
an error because the differences are mostly irrelevant and it's nice to
avoid breaking users with slightly incorrect ACPI/DT.
Signed-off-by: Crestez Dan Leonard <leonard.crestez@intel.com>
Acked-by: Ge Gao <ggao@invensense.com>
Signed-off-by: Jonathan Cameron <jic23@kernel.org>
Diffstat (limited to 'drivers')
| -rw-r--r-- | drivers/iio/imu/inv_mpu6050/inv_mpu_core.c | 15 | ||||
| -rw-r--r-- | drivers/iio/imu/inv_mpu6050/inv_mpu_iio.h | 8 |
2 files changed, 23 insertions, 0 deletions
diff --git a/drivers/iio/imu/inv_mpu6050/inv_mpu_core.c b/drivers/iio/imu/inv_mpu6050/inv_mpu_core.c index 84d5b6939e6a..4152f2fcf598 100644 --- a/drivers/iio/imu/inv_mpu6050/inv_mpu_core.c +++ b/drivers/iio/imu/inv_mpu6050/inv_mpu_core.c @@ -91,16 +91,19 @@ static const struct inv_mpu6050_chip_config chip_config_6050 = { /* Indexed by enum inv_devices */ static const struct inv_mpu6050_hw hw_info[] = { { + .whoami = INV_MPU6050_WHOAMI_VALUE, .name = "MPU6050", .reg = ®_set_6050, .config = &chip_config_6050, }, { + .whoami = INV_MPU6500_WHOAMI_VALUE, .name = "MPU6500", .reg = ®_set_6500, .config = &chip_config_6050, }, { + .whoami = INV_MPU6000_WHOAMI_VALUE, .name = "MPU6000", .reg = ®_set_6050, .config = &chip_config_6050, @@ -749,6 +752,7 @@ static const struct iio_info mpu_info = { static int inv_check_and_setup_chip(struct inv_mpu6050_state *st) { int result; + unsigned int regval; st->hw = &hw_info[st->chip_type]; st->reg = hw_info[st->chip_type].reg; @@ -759,6 +763,17 @@ static int inv_check_and_setup_chip(struct inv_mpu6050_state *st) if (result) return result; msleep(INV_MPU6050_POWER_UP_TIME); + + /* check chip self-identification */ + result = regmap_read(st->map, INV_MPU6050_REG_WHOAMI, ®val); + if (result) + return result; + if (regval != st->hw->whoami) { + dev_warn(regmap_get_device(st->map), + "whoami mismatch got %#02x expected %#02hhx for %s\n", + regval, st->hw->whoami, st->hw->name); + } + /* * toggle power state. After reset, the sleep bit could be on * or off depending on the OTP settings. Toggling power would diff --git a/drivers/iio/imu/inv_mpu6050/inv_mpu_iio.h b/drivers/iio/imu/inv_mpu6050/inv_mpu_iio.h index 26b63993ba00..fb45cc76e4e4 100644 --- a/drivers/iio/imu/inv_mpu6050/inv_mpu_iio.h +++ b/drivers/iio/imu/inv_mpu6050/inv_mpu_iio.h @@ -93,11 +93,13 @@ struct inv_mpu6050_chip_config { /** * struct inv_mpu6050_hw - Other important hardware information. + * @whoami: Self identification byte from WHO_AM_I register * @name: name of the chip. * @reg: register map of the chip. * @config: configuration of the chip. */ struct inv_mpu6050_hw { + u8 whoami; u8 *name; const struct inv_mpu6050_reg_map *reg; const struct inv_mpu6050_chip_config *config; @@ -215,6 +217,12 @@ struct inv_mpu6050_state { #define INV_MPU6050_MIN_FIFO_RATE 4 #define INV_MPU6050_ONE_K_HZ 1000 +#define INV_MPU6050_REG_WHOAMI 117 + +#define INV_MPU6000_WHOAMI_VALUE 0x68 +#define INV_MPU6050_WHOAMI_VALUE 0x68 +#define INV_MPU6500_WHOAMI_VALUE 0x70 + /* scan element definition */ enum inv_mpu6050_scan { INV_MPU6050_SCAN_ACCL_X, |