Re: [PATCH v2 10/24] media: iris: Fix missing LAST flag handling during drain

[Bryan O'Donoghue <bryan.odonoghue@linaro.org>]

On 13/08/2025 10:38, Dikshita Agarwal wrote:
> Improve drain handling by ensuring the LAST flag is attached to final
> capture buffer when drain response is received from the firmware.
> 
> Previously, the driver failed to attach the V4L2_BUF_FLAG_LAST flag when
> a drain response was received from the firmware, relying on userspace to
> mark the next queued buffer as LAST. This update fixes the issue by
> checking the pending drain status, attaching the LAST flag to the
> capture buffer received from the firmware (with EOS attached), and
> returning it to the V4L2 layer correctly.
> 
> Fixes: d09100763bed ("media: iris: add support for drain sequence")
> Reviewed-by: Vikash Garodia <quic_vgarodia@quicinc.com>
> Tested-by: Vikash Garodia <quic_vgarodia@quicinc.com> # X1E80100
> Signed-off-by: Dikshita Agarwal <quic_dikshita@quicinc.com>
> ---
>   drivers/media/platform/qcom/iris/iris_hfi_gen1_response.c | 4 +---
>   drivers/media/platform/qcom/iris/iris_state.c             | 2 +-
>   drivers/media/platform/qcom/iris/iris_state.h             | 1 +
>   3 files changed, 3 insertions(+), 4 deletions(-)
> 
> diff --git a/drivers/media/platform/qcom/iris/iris_hfi_gen1_response.c b/drivers/media/platform/qcom/iris/iris_hfi_gen1_response.c
> index 8d1ce8a19a45ebb2b29457e0fef7d72c1c0d9785..2a96458833835422d30c9386d15cc1e4fb226e3d 100644
> --- a/drivers/media/platform/qcom/iris/iris_hfi_gen1_response.c
> +++ b/drivers/media/platform/qcom/iris/iris_hfi_gen1_response.c
> @@ -416,8 +416,6 @@ static void iris_hfi_gen1_session_ftb_done(struct iris_inst *inst, void *packet)
>   			inst->flush_responses_pending++;
>   
>   		iris_inst_sub_state_change_drain_last(inst);
> -
> -		return;
>   	}
>   
>   	if (iris_split_mode_enabled(inst) && pkt->stream_id == 0) {
> @@ -462,7 +460,7 @@ static void iris_hfi_gen1_session_ftb_done(struct iris_inst *inst, void *packet)
>   		timestamp_us = (timestamp_us << 32) | timestamp_lo;
>   	} else {
>   		if (pkt->stream_id == 1 && !inst->last_buffer_dequeued) {
> -			if (iris_drc_pending(inst)) {
> +			if (iris_drc_pending(inst) || iris_drain_pending(inst)) {
>   				flags |= V4L2_BUF_FLAG_LAST;
>   				inst->last_buffer_dequeued = true;
>   			}
> diff --git a/drivers/media/platform/qcom/iris/iris_state.c b/drivers/media/platform/qcom/iris/iris_state.c
> index a21238d2818f9606871953bd0bee25382cca0474..d1dc1a863da0b0b1af60974e9ed2ef68ea225cdd 100644
> --- a/drivers/media/platform/qcom/iris/iris_state.c
> +++ b/drivers/media/platform/qcom/iris/iris_state.c
> @@ -252,7 +252,7 @@ bool iris_drc_pending(struct iris_inst *inst)
>   		inst->sub_state & IRIS_INST_SUB_DRC_LAST;
>   }
>   
> -static inline bool iris_drain_pending(struct iris_inst *inst)
> +bool iris_drain_pending(struct iris_inst *inst)
>   {
>   	return inst->sub_state & IRIS_INST_SUB_DRAIN &&
>   		inst->sub_state & IRIS_INST_SUB_DRAIN_LAST;
> diff --git a/drivers/media/platform/qcom/iris/iris_state.h b/drivers/media/platform/qcom/iris/iris_state.h
> index e718386dbe0402417f408d8fc696a33e5c7f23b3..b09fa54cf17eeee0c9ae254588964ad959c82c80 100644
> --- a/drivers/media/platform/qcom/iris/iris_state.h
> +++ b/drivers/media/platform/qcom/iris/iris_state.h
> @@ -141,5 +141,6 @@ int iris_inst_sub_state_change_drc_last(struct iris_inst *inst);
>   int iris_inst_sub_state_change_pause(struct iris_inst *inst, u32 plane);
>   bool iris_allow_cmd(struct iris_inst *inst, u32 cmd);
>   bool iris_drc_pending(struct iris_inst *inst);
> +bool iris_drain_pending(struct iris_inst *inst);
>   
>   #endif
> 
Reviewed-by: Bryan O'Donoghue <bryan.odonoghue@linaro.org>