Re: [PATCH 0/3] ASoC: qcom: q6apm: Fix shared memory unmap

[Srinivas Kandagatla <srinivas.kandagatla@oss.qualcomm.com>]

On 10/16/26 3:11 PM, Shawn Guo wrote:
> Since the early buffer mapping, q6apm maps a front-end's DSP buffers
> once in pcm_new() and unmaps them in pcm_free(). The unmap side has a
> few problems, which show up when the sound card is unbound and bound
> again, e.g. by unbinding and binding any codec on the card:
> 
> - The card core removes the components before it frees the PCMs, so
>   the topology and its graph info are gone by the time pcm_free()
>   tries to unmap. The unmap is silently skipped, the DSP keeps the old
>   mapping, and the next bind fails to create the PCM:
> 
>     qcom-apm gprsvc:service:2:1: Error (1) Processing 0x0100100c cmd
>     snd-sc8280xp sound: ASoC: can't create pcm MultiMedia1 Playback :-22
> 
> - Once unmap is actually sent, every command stalls for five seconds,
>   because the response handler matches on the wrong opcode:
> 
>     qcom-apm gprsvc:service:2:1: CMD timeout for [100100d] opcode
> 
> - Unmapping the position buffer clears the circular buffer's handle
>   instead of its own.
> 
> Patch 1 fixes the unmap response handling, patch 2 makes the position
> buffer unmap clear its own handle, and patch 3 moves the unmap to the
> APM component's remove callback, before the topology is unloaded.
> Patches 1 and 2 go first so that patch 3 does not introduce the five
> second stalls.
> 
> Tested on Qualcomm Ride board by unbinding and binding the PCM1681
> codec.
> 
>   echo 0-004c > /sys/bus/i2c/drivers/pcm1681/unbind
>   echo 0-004c > /sys/bus/i2c/drivers/pcm1681/bind

Thanks for trying this case and fixing some of the issues.

Can you pl add Stable tag for these.

Other than than they look good to me.

Reviewed-by: Srinivas Kandagatla <srinivas.kandagatla@oss.qualcomm.com>

--srini
> 
> Shawn Guo (3):
>   ASoC: qcom: q6apm: Fix unmap regions response handling
>   ASoC: qcom: q6apm: Clear the right handle on pos buffer unmap
>   ASoC: qcom: q6apm: Unmap DSP buffers before removing the topology
> 
>  sound/soc/qcom/qdsp6/q6apm.c | 49 ++++++++++++++++++++++++++----------
>  1 file changed, 36 insertions(+), 13 deletions(-)
>