This is a note to let you know that I've just added the patch titled iio: imu: inv_mpu6050: add accel lpf setting for chip >= MPU6500 to the 4.11-stable tree which can be found at: http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=summary The filename of the patch is: iio-imu-inv_mpu6050-add-accel-lpf-setting-for-chip-mpu6500.patch and it can be found in the queue-4.11 subdirectory. If you, or anyone else, feels it should not be added to the stable tree, please let <stable@xxxxxxxxxxxxxxx> know about it. >From 948588e25b8af5e66962ed3f53e1cae1656fa5af Mon Sep 17 00:00:00 2001 From: Jean-Baptiste Maneyrol <JManeyrol@xxxxxxxxxxxxxx> Date: Mon, 29 May 2017 09:59:40 +0000 Subject: iio: imu: inv_mpu6050: add accel lpf setting for chip >= MPU6500 From: Jean-Baptiste Maneyrol <JManeyrol@xxxxxxxxxxxxxx> commit 948588e25b8af5e66962ed3f53e1cae1656fa5af upstream. Starting from MPU6500, accelerometer dlpf is set in a separate register named ACCEL_CONFIG_2. Add this new register in the map and set it for the corresponding chips. Signed-off-by: Jean-Baptiste Maneyrol <jmaneyrol@xxxxxxxxxxxxxx> Signed-off-by: Jonathan Cameron <jic23@xxxxxxxxxx> Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx> --- drivers/iio/imu/inv_mpu6050/inv_mpu_core.c | 39 ++++++++++++++++++++++++++--- drivers/iio/imu/inv_mpu6050/inv_mpu_iio.h | 3 ++ 2 files changed, 39 insertions(+), 3 deletions(-) --- a/drivers/iio/imu/inv_mpu6050/inv_mpu_core.c +++ b/drivers/iio/imu/inv_mpu6050/inv_mpu_core.c @@ -41,6 +41,7 @@ static const int accel_scale[] = {598, 1 static const struct inv_mpu6050_reg_map reg_set_6500 = { .sample_rate_div = INV_MPU6050_REG_SAMPLE_RATE_DIV, .lpf = INV_MPU6050_REG_CONFIG, + .accel_lpf = INV_MPU6500_REG_ACCEL_CONFIG_2, .user_ctrl = INV_MPU6050_REG_USER_CTRL, .fifo_en = INV_MPU6050_REG_FIFO_EN, .gyro_config = INV_MPU6050_REG_GYRO_CONFIG, @@ -205,6 +206,37 @@ int inv_mpu6050_set_power_itg(struct inv EXPORT_SYMBOL_GPL(inv_mpu6050_set_power_itg); /** + * inv_mpu6050_set_lpf_regs() - set low pass filter registers, chip dependent + * + * MPU60xx/MPU9150 use only 1 register for accelerometer + gyroscope + * MPU6500 and above have a dedicated register for accelerometer + */ +static int inv_mpu6050_set_lpf_regs(struct inv_mpu6050_state *st, + enum inv_mpu6050_filter_e val) +{ + int result; + + result = regmap_write(st->map, st->reg->lpf, val); + if (result) + return result; + + switch (st->chip_type) { + case INV_MPU6050: + case INV_MPU6000: + case INV_MPU9150: + /* old chips, nothing to do */ + result = 0; + break; + default: + /* set accel lpf */ + result = regmap_write(st->map, st->reg->accel_lpf, val); + break; + } + + return result; +} + +/** * inv_mpu6050_init_config() - Initialize hardware, disable FIFO. * * Initial configuration: @@ -227,8 +259,7 @@ static int inv_mpu6050_init_config(struc if (result) return result; - d = INV_MPU6050_FILTER_20HZ; - result = regmap_write(st->map, st->reg->lpf, d); + result = inv_mpu6050_set_lpf_regs(st, INV_MPU6050_FILTER_20HZ); if (result) return result; @@ -531,6 +562,8 @@ error_write_raw: * would be alising. This function basically search for the * correct low pass parameters based on the fifo rate, e.g, * sampling frequency. + * + * lpf is set automatically when setting sampling rate to avoid any aliases. */ static int inv_mpu6050_set_lpf(struct inv_mpu6050_state *st, int rate) { @@ -546,7 +579,7 @@ static int inv_mpu6050_set_lpf(struct in while ((h < hz[i]) && (i < ARRAY_SIZE(d) - 1)) i++; data = d[i]; - result = regmap_write(st->map, st->reg->lpf, data); + result = inv_mpu6050_set_lpf_regs(st, data); if (result) return result; st->chip_config.lpf = data; --- a/drivers/iio/imu/inv_mpu6050/inv_mpu_iio.h +++ b/drivers/iio/imu/inv_mpu6050/inv_mpu_iio.h @@ -28,6 +28,7 @@ * struct inv_mpu6050_reg_map - Notable registers. * @sample_rate_div: Divider applied to gyro output rate. * @lpf: Configures internal low pass filter. + * @accel_lpf: Configures accelerometer low pass filter. * @user_ctrl: Enables/resets the FIFO. * @fifo_en: Determines which data will appear in FIFO. * @gyro_config: gyro config register. @@ -47,6 +48,7 @@ struct inv_mpu6050_reg_map { u8 sample_rate_div; u8 lpf; + u8 accel_lpf; u8 user_ctrl; u8 fifo_en; u8 gyro_config; @@ -187,6 +189,7 @@ struct inv_mpu6050_state { #define INV_MPU6050_FIFO_THRESHOLD 500 /* mpu6500 registers */ +#define INV_MPU6500_REG_ACCEL_CONFIG_2 0x1D #define INV_MPU6500_REG_ACCEL_OFFSET 0x77 /* delay time in milliseconds */ Patches currently in stable-queue which might be from JManeyrol@xxxxxxxxxxxxxx are queue-4.11/iio-imu-inv_mpu6050-add-accel-lpf-setting-for-chip-mpu6500.patch