[PATCH v2 4/5] drm/mediatek: Automatically search unclaimed mtk mutex in mtk_mutex_get()

Chun-Kuang Hu
2021-01-06T23:20:28Z

From: CK Hu <ck.hu@mediatek.com>

Moving mutex resource management from client driver to mutex driver
could prevent client drivers negotiating for resource management.

Signed-off-by: CK Hu <ck.hu@mediatek.com>
Signed-off-by: Chun-Kuang Hu <chunkuang.hu@kernel.org>
---
drivers/gpu/drm/mediatek/mtk_drm_crtc.c | 2 +-
drivers/gpu/drm/mediatek/mtk_mutex.c | 16 ++++++++--------
drivers/gpu/drm/mediatek/mtk_mutex.h | 2 +-
3 files changed, 10 insertions(+), 10 deletions(-)

diff --git a/drivers/gpu/drm/mediatek/mtk_drm_crtc.c b/drivers/gpu/drm/mediatek/mtk_drm_crtc.c
index bba87a036fa8..1e3a9450680b 100644
--- a/drivers/gpu/drm/mediatek/mtk_drm_crtc.c
+++ b/drivers/gpu/drm/mediatek/mtk_drm_crtc.c
@@ -773,7 +773,7 @@ int mtk_drm_crtc_create(struct drm_device *drm_dev,
if (!mtk_crtc->ddp_comp)
return -ENOMEM;

- mtk_crtc->mutex = mtk_mutex_get(priv->mutex_dev, pipe);
+ mtk_crtc->mutex = mtk_mutex_get(priv->mutex_dev);
if (IS_ERR(mtk_crtc->mutex)) {
ret = PTR_ERR(mtk_crtc->mutex);
dev_err(dev, "Failed to get mutex: %d\n", ret);
diff --git a/drivers/gpu/drm/mediatek/mtk_mutex.c b/drivers/gpu/drm/mediatek/mtk_mutex.c
index 98a060bf225d..66344759e622 100644
--- a/drivers/gpu/drm/mediatek/mtk_mutex.c
+++ b/drivers/gpu/drm/mediatek/mtk_mutex.c
@@ -228,18 +228,18 @@ static const struct mtk_mutex_data mt8173_mutex_driver_data = {
.mutex_sof_reg = MT2701_MUTEX0_SOF0,
};

-struct mtk_mutex *mtk_mutex_get(struct device *dev, unsigned int id)
+struct mtk_mutex *mtk_mutex_get(struct device *dev)
{
struct mtk_mutex_ctx *mtx = dev_get_drvdata(dev);
+ int i;

- if (id >= 10)
- return ERR_PTR(-EINVAL);
- if (mtx->mutex[id].claimed)
- return ERR_PTR(-EBUSY);
-
- mtx->mutex[id].claimed = true;
+ for (i = 0; i < 10; i++)
+ if (!mtx->mutex[i].claimed) {
+ mtx->mutex[i].claimed = true;
+ return &mtx->mutex[i];
+ }

- return &mtx->mutex[id];
+ return ERR_PTR(-EBUSY);
}

void mtk_mutex_put(struct mtk_mutex *mutex)
diff --git a/drivers/gpu/drm/mediatek/mtk_mutex.h b/drivers/gpu/drm/mediatek/mtk_mutex.h
index b678e0988a37..6fe4ffbde290 100644
--- a/drivers/gpu/drm/mediatek/mtk_mutex.h
+++ b/drivers/gpu/drm/mediatek/mtk_mutex.h
@@ -10,7 +10,7 @@ struct regmap;
struct device;
struct mtk_mutex;

-struct mtk_mutex *mtk_mutex_get(struct device *dev, unsigned int id);
+struct mtk_mutex *mtk_mutex_get(struct device *dev);
int mtk_mutex_prepare(struct mtk_mutex *mutex);
void mtk_mutex_add_comp(struct mtk_mutex *mutex,
enum mtk_ddp_comp_id id);
--
2.17.1