[git:media_stage/master] media: mediatek: vcodec: fix possible unbalanced PM counter

[Hans Verkuil]

This is an automatic generated email to let you know that the following patch 
were queued:

Subject: media: mediatek: vcodec: fix possible unbalanced PM counter
Author:  Eugen Hristev <eugen.hris...@collabora.com>
Date:    Thu Dec 28 13:32:40 2023 +0200

It is possible that mtk_vcodec_enc_pw_on fails, and in that scenario
the PM counter is not incremented, and subsequent call to
mtk_vcodec_enc_pw_off decrements the counter, leading to a PM imbalance.
Fix by bailing out of venc_if_encode in the case when mtk_vcodec_enc_pw_on
fails.

Fixes: 4e855a6efa54 ("[media] vcodec: mediatek: Add Mediatek V4L2 Video Encoder 
Driver")
Signed-off-by: Eugen Hristev <eugen.hris...@collabora.com>
Reviewed-by: AngeloGioacchino Del Regno 
<angelogioacchino.delre...@collabora.com>
Signed-off-by: Andrzej Pietrasiewicz <andrze...@collabora.com>
Signed-off-by: Sebastian Fricke <sebastian.fri...@collabora.com>
Signed-off-by: Hans Verkuil <hverkuil-ci...@xs4all.nl>

 drivers/media/platform/mediatek/vcodec/encoder/mtk_vcodec_enc_pm.c | 4 +++-
 drivers/media/platform/mediatek/vcodec/encoder/mtk_vcodec_enc_pm.h | 2 +-
 drivers/media/platform/mediatek/vcodec/encoder/venc_drv_if.c       | 5 ++++-
 3 files changed, 8 insertions(+), 3 deletions(-)

---

diff --git a/drivers/media/platform/mediatek/vcodec/encoder/mtk_vcodec_enc_pm.c 
b/drivers/media/platform/mediatek/vcodec/encoder/mtk_vcodec_enc_pm.c
index a22b7dfc656e..1a2b14a3e219 100644
--- a/drivers/media/platform/mediatek/vcodec/encoder/mtk_vcodec_enc_pm.c
+++ b/drivers/media/platform/mediatek/vcodec/encoder/mtk_vcodec_enc_pm.c
@@ -58,13 +58,15 @@ int mtk_vcodec_init_enc_clk(struct mtk_vcodec_enc_dev 
*mtkdev)
        return 0;
 }
 
-void mtk_vcodec_enc_pw_on(struct mtk_vcodec_pm *pm)
+int mtk_vcodec_enc_pw_on(struct mtk_vcodec_pm *pm)
 {
        int ret;
 
        ret = pm_runtime_resume_and_get(pm->dev);
        if (ret)
                dev_err(pm->dev, "pm_runtime_resume_and_get fail: %d", ret);
+
+       return ret;
 }
 
 void mtk_vcodec_enc_pw_off(struct mtk_vcodec_pm *pm)
diff --git a/drivers/media/platform/mediatek/vcodec/encoder/mtk_vcodec_enc_pm.h 
b/drivers/media/platform/mediatek/vcodec/encoder/mtk_vcodec_enc_pm.h
index 157ea08ba9e3..2e28f25e36cc 100644
--- a/drivers/media/platform/mediatek/vcodec/encoder/mtk_vcodec_enc_pm.h
+++ b/drivers/media/platform/mediatek/vcodec/encoder/mtk_vcodec_enc_pm.h
@@ -10,7 +10,7 @@
 #include "mtk_vcodec_enc_drv.h"
 
 int mtk_vcodec_init_enc_clk(struct mtk_vcodec_enc_dev *dev);
-void mtk_vcodec_enc_pw_on(struct mtk_vcodec_pm *pm);
+int mtk_vcodec_enc_pw_on(struct mtk_vcodec_pm *pm);
 void mtk_vcodec_enc_pw_off(struct mtk_vcodec_pm *pm);
 void mtk_vcodec_enc_clock_on(struct mtk_vcodec_pm *pm);
 void mtk_vcodec_enc_clock_off(struct mtk_vcodec_pm *pm);
diff --git a/drivers/media/platform/mediatek/vcodec/encoder/venc_drv_if.c 
b/drivers/media/platform/mediatek/vcodec/encoder/venc_drv_if.c
index c402a686f3cb..e83747b8d69a 100644
--- a/drivers/media/platform/mediatek/vcodec/encoder/venc_drv_if.c
+++ b/drivers/media/platform/mediatek/vcodec/encoder/venc_drv_if.c
@@ -64,7 +64,9 @@ int venc_if_encode(struct mtk_vcodec_enc_ctx *ctx,
        ctx->dev->curr_ctx = ctx;
        spin_unlock_irqrestore(&ctx->dev->irqlock, flags);
 
-       mtk_vcodec_enc_pw_on(&ctx->dev->pm);
+       ret = mtk_vcodec_enc_pw_on(&ctx->dev->pm);
+       if (ret)
+               goto venc_if_encode_pw_on_err;
        mtk_vcodec_enc_clock_on(&ctx->dev->pm);
        ret = ctx->enc_if->encode(ctx->drv_handle, opt, frm_buf,
                                  bs_buf, result);
@@ -75,6 +77,7 @@ int venc_if_encode(struct mtk_vcodec_enc_ctx *ctx,
        ctx->dev->curr_ctx = NULL;
        spin_unlock_irqrestore(&ctx->dev->irqlock, flags);
 
+venc_if_encode_pw_on_err:
        mtk_venc_unlock(ctx);
        return ret;
 }