On Wed, 05 Aug 2020 11:11:15 +0200,
Mohan Kumar wrote:
>
> Behaviour flag dma_stop_delay is added as a new member in hdac_bus
> structure to avoid memory decode error incase DMA RUN bit is not
> disabled in the given timeout from snd_hdac_stream_sync function and
> followed by stream reset which results in memory decode error between
> reset set and clear operation.
The new field looks like not only a flag but also contains the actual
delay time in usec. Please give a short comment at the struct field.
thanks,
Takashi
>
> Signed-off-by: Mohan Kumar <mkumard@xxxxxxxxxx>
> ---
> include/sound/hdaudio.h | 2 ++
> sound/hda/hdac_stream.c | 7 +++++++
> 2 files changed, 9 insertions(+)
>
> diff --git a/include/sound/hdaudio.h b/include/sound/hdaudio.h
> index c1f78d9a6e47..cf77c6b83016 100644
> --- a/include/sound/hdaudio.h
> +++ b/include/sound/hdaudio.h
> @@ -347,6 +347,8 @@ struct hdac_bus {
>
> int bdl_pos_adj; /* BDL position adjustment */
>
> + unsigned int dma_stop_delay;
> +
> /* locks */
> spinlock_t reg_lock;
> struct mutex cmd_mutex;
> diff --git a/sound/hda/hdac_stream.c b/sound/hda/hdac_stream.c
> index a38a2af1654f..abe7a1b16fe1 100644
> --- a/sound/hda/hdac_stream.c
> +++ b/sound/hda/hdac_stream.c
> @@ -150,9 +150,12 @@ void snd_hdac_stream_reset(struct hdac_stream *azx_dev)
> {
> unsigned char val;
> int timeout;
> + int dma_run_state;
>
> snd_hdac_stream_clear(azx_dev);
>
> + dma_run_state = snd_hdac_stream_readb(azx_dev, SD_CTL) & SD_CTL_DMA_START;
> +
> snd_hdac_stream_updateb(azx_dev, SD_CTL, 0, SD_CTL_STREAM_RESET);
> udelay(3);
> timeout = 300;
> @@ -162,6 +165,10 @@ void snd_hdac_stream_reset(struct hdac_stream *azx_dev)
> if (val)
> break;
> } while (--timeout);
> +
> + if (azx_dev->bus->dma_stop_delay && dma_run_state)
> + udelay(azx_dev->bus->dma_stop_delay);
> +
> val &= ~SD_CTL_STREAM_RESET;
> snd_hdac_stream_writeb(azx_dev, SD_CTL, val);
> udelay(3);
> --
> 2.17.1
>
