Re: [PATCH v3 10/23] media: iris: Track flush responses to prevent premature completion

[Dikshita Agarwal]

On 5/2/2025 6:10 PM, Bryan O'Donoghue wrote:
> On 01/05/2025 20:13, Dikshita Agarwal wrote:
>> Currently, two types of flush commands are queued to the firmware,
>> the first flush queued as part of sequence change, does not wait for a
>> response, while the second flush queued as part of stop, expects a
>> completion response before proceeding further.
>>
>> Due to timing issue, the flush response corresponding to the first
>> command could arrive after the second flush is issued. This casuses the
>> driver to incorrectly assume that the second flush has completed,
>> leading to the premature signaling of flush_completion.
>>
>> To address this, introduce a counter to track the number of pending
>> flush responses and signal flush completion only when all expected
>> responses are received.
> 
> Is there no other way to correlate command/response than a counter on the
> APSS side ?
> 
> Usually command/response protocols have some kind of identifier field or
> sequence number embedded in the protocol headers.
> 
There is no such identifier field for flush command and response at the moment.

Thanks,
Dikshita
> ---
> bod