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From:   Alexandre Courbot <acourbot@chromium.org>
To:     Stanimir Varbanov <stanimir.varbanov@linaro.org>
Cc:     linux-media@vger.kernel.org, linux-arm-msm@vger.kernel.org,
        linux-kernel@vger.kernel.org,
        Alexandre Courbot <acourbot@chromium.org>
Subject: [PATCH] media: venus: preserve DRC state across seeks
Date:   Wed,  2 Dec 2020 14:34:24 +0900
Message-Id: <20201202053424.3286774-1-acourbot@chromium.org>
MIME-Version: 1.0
Content-Transfer-Encoding: 8bit
Precedence: bulk

DRC events can happen virtually at anytime, including when we are
starting a seek. Should this happen, we must make sure to return to the
DRC state, otherwise the firmware will expect buffers of the new
resolution whereas userspace will still work with the old one.

Returning to the DRC state upon resume for seeking makes sure that the
client will get the DRC event and will reallocate the buffers to fit the
firmware's expectations.

Signed-off-by: Alexandre Courbot <acourbot@chromium.org>
---
 drivers/media/platform/qcom/venus/vdec.c | 11 +++++++++--
 1 file changed, 9 insertions(+), 2 deletions(-)

diff --git a/drivers/media/platform/qcom/venus/vdec.c b/drivers/media/platform/qcom/venus/vdec.c
index 8488411204c3..e3d0df7fd765 100644
--- a/drivers/media/platform/qcom/venus/vdec.c
+++ b/drivers/media/platform/qcom/venus/vdec.c
@@ -972,7 +972,10 @@ static int vdec_start_output(struct venus_inst *inst)
 
 	if (inst->codec_state == VENUS_DEC_STATE_SEEK) {
 		ret = venus_helper_process_initial_out_bufs(inst);
-		inst->codec_state = VENUS_DEC_STATE_DECODING;
+		if (inst->next_buf_last)
+			inst->codec_state = VENUS_DEC_STATE_DRC;
+		else
+			inst->codec_state = VENUS_DEC_STATE_DECODING;
 		goto done;
 	}
 
@@ -1077,8 +1080,10 @@ static int vdec_stop_capture(struct venus_inst *inst)
 		ret = hfi_session_flush(inst, HFI_FLUSH_ALL, true);
 		fallthrough;
 	case VENUS_DEC_STATE_DRAIN:
-		vdec_cancel_dst_buffers(inst);
 		inst->codec_state = VENUS_DEC_STATE_STOPPED;
+		fallthrough;
+	case VENUS_DEC_STATE_SEEK:
+		vdec_cancel_dst_buffers(inst);
 		break;
 	case VENUS_DEC_STATE_DRC:
 		WARN_ON(1);
@@ -1102,6 +1107,7 @@ static int vdec_stop_output(struct venus_inst *inst)
 	case VENUS_DEC_STATE_DECODING:
 	case VENUS_DEC_STATE_DRAIN:
 	case VENUS_DEC_STATE_STOPPED:
+	case VENUS_DEC_STATE_DRC:
 		ret = hfi_session_flush(inst, HFI_FLUSH_ALL, true);
 		inst->codec_state = VENUS_DEC_STATE_SEEK;
 		break;
@@ -1371,6 +1377,7 @@ static void vdec_event_change(struct venus_inst *inst,
 			dev_dbg(dev, VDBGH "flush output error %d\n", ret);
 	}
 
+	inst->next_buf_last = true;
 	inst->reconfig = true;
 	v4l2_event_queue_fh(&inst->fh, &ev);
 	wake_up(&inst->reconf_wait);
-- 
2.29.2.454.gaff20da3a2-goog