iio: inv_mpu6050: Clear timestamps fifo while resetting hardware fifo

commit 4dac0a8eefd55bb1f157d1a5a084531334a2d74c upstream.

A hardware fifo reset always imply an invalidation of the
existing timestamps, so we'll clear timestamps fifo on
successfull hardware fifo reset.

Signed-off-by: Viorel Suman <viorel.suman@gmail.com>
Signed-off-by: Jonathan Cameron <jic23@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

diff --git a/drivers/iio/imu/inv_mpu6050/inv_mpu_ring.c b/drivers/iio/imu/inv_mpu6050/inv_mpu_ring.c
index 7da0832f187b8d320cd8618eb3379b2015bee927..01d661e0fa6cd81535fc069a8a339916d233978d 100644 (file)
--- a/drivers/iio/imu/inv_mpu6050/inv_mpu_ring.c
+++ b/drivers/iio/imu/inv_mpu6050/inv_mpu_ring.c
@@ -25,6 +25,16 @@
 #include <linux/poll.h>
 #include "inv_mpu_iio.h"
 
+static void inv_clear_kfifo(struct inv_mpu6050_state *st)
+{
+       unsigned long flags;
+
+       /* take the spin lock sem to avoid interrupt kick in */
+       spin_lock_irqsave(&st->time_stamp_lock, flags);
+       kfifo_reset(&st->timestamps);
+       spin_unlock_irqrestore(&st->time_stamp_lock, flags);
+}
+
 int inv_reset_fifo(struct iio_dev *indio_dev)
 {
        int result;
@@ -51,6 +61,10 @@ int inv_reset_fifo(struct iio_dev *indio_dev)
                                        INV_MPU6050_BIT_FIFO_RST);
        if (result)
                goto reset_fifo_fail;
+
+       /* clear timestamps fifo */
+       inv_clear_kfifo(st);
+
        /* enable interrupt */
        if (st->chip_config.accl_fifo_enable ||
            st->chip_config.gyro_fifo_enable) {
@@ -84,16 +98,6 @@ reset_fifo_fail:
        return result;
 }
 
-static void inv_clear_kfifo(struct inv_mpu6050_state *st)
-{
-       unsigned long flags;
-
-       /* take the spin lock sem to avoid interrupt kick in */
-       spin_lock_irqsave(&st->time_stamp_lock, flags);
-       kfifo_reset(&st->timestamps);
-       spin_unlock_irqrestore(&st->time_stamp_lock, flags);
-}
-
 /**
  * inv_mpu6050_irq_handler() - Cache a timestamp at each data ready interrupt.
  */
@@ -187,7 +191,6 @@ end_session:
 flush_fifo:
        /* Flush HW and SW FIFOs. */
        inv_reset_fifo(indio_dev);
-       inv_clear_kfifo(st);
        mutex_unlock(&indio_dev->mlock);
        iio_trigger_notify_done(indio_dev->trig);