Re: [PATCH] Clear timestamp kfifo on trigger enabling

From: Peter Meerwald
Date: Mon Feb 16 2015 - 16:21:38 EST



> The timestamp kfifo must be cleared once the
> hardware fifo is reset, thus are removed
> timestamps related to unprocessed events from
> hardware fifo - see "inv_mpu6050_read_fifo"
> method implementation.

comments below
a prefix iio: in the subject would be nice

> Signed-off-by: Viorel Suman <viorel.suman@xxxxxxxxx>
> ---
> drivers/iio/imu/inv_mpu6050/inv_mpu_trigger.c | 28 +++++++++++++++------------
> 1 file changed, 16 insertions(+), 12 deletions(-)
>
> diff --git a/drivers/iio/imu/inv_mpu6050/inv_mpu_trigger.c b/drivers/iio/imu/inv_mpu6050/inv_mpu_trigger.c
> index 926fcce..b617920 100644
> --- a/drivers/iio/imu/inv_mpu6050/inv_mpu_trigger.c
> +++ b/drivers/iio/imu/inv_mpu6050/inv_mpu_trigger.c
> @@ -42,57 +42,61 @@ static void inv_scan_query(struct iio_dev *indio_dev)
> static int inv_mpu6050_set_enable(struct iio_dev *indio_dev, bool enable)
> {
> struct inv_mpu6050_state *st = iio_priv(indio_dev);
> - int result;
> + int result = 0;

no need to init result

the mutex could be obtained in the caller, i.e.
inv_mpu_data_rdy_trigger_set_state(), simplifying the code and drastically
reducing the size of this patch

the patch description does not explain a mutex is (now?) needed; probably
this should be split out as a separate patch

>
> + mutex_lock(&indio_dev->mlock);
> if (enable) {
> result = inv_mpu6050_set_power_itg(st, true);
> if (result)
> - return result;
> + goto write_error;
> inv_scan_query(indio_dev);
> if (st->chip_config.gyro_fifo_enable) {
> result = inv_mpu6050_switch_engine(st, true,
> INV_MPU6050_BIT_PWR_GYRO_STBY);
> if (result)
> - return result;
> + goto write_error;
> }
> if (st->chip_config.accl_fifo_enable) {
> result = inv_mpu6050_switch_engine(st, true,
> INV_MPU6050_BIT_PWR_ACCL_STBY);
> if (result)
> - return result;
> + goto write_error;
> }
> + inv_clear_kfifo(st);
> result = inv_reset_fifo(indio_dev);
> if (result)
> - return result;
> + goto write_error;
> } else {
> result = inv_mpu6050_write_reg(st, st->reg->fifo_en, 0);
> if (result)
> - return result;
> + goto write_error;
>
> result = inv_mpu6050_write_reg(st, st->reg->int_enable, 0);
> if (result)
> - return result;
> + goto write_error;
>
> result = inv_mpu6050_write_reg(st, st->reg->user_ctrl, 0);
> if (result)
> - return result;
> + goto write_error;
>
> result = inv_mpu6050_switch_engine(st, false,
> INV_MPU6050_BIT_PWR_GYRO_STBY);
> if (result)
> - return result;
> + goto write_error;
>
> result = inv_mpu6050_switch_engine(st, false,
> INV_MPU6050_BIT_PWR_ACCL_STBY);
> if (result)
> - return result;
> + goto write_error;
> result = inv_mpu6050_set_power_itg(st, false);
> if (result)
> - return result;
> + goto write_error;
> }
> st->chip_config.enable = enable;
> +write_error:
> + mutex_unlock(&indio_dev->mlock);
>
> - return 0;
> + return result;
> }
>
> /**
>

--

Peter Meerwald
+43-664-2444418 (mobile)
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