[PATCH AUTOSEL 6.12 16/31] drm/exynos: hdmi: use eld_mutex to protect access to connector->eld

[Sasha Levin <sashal@kernel.org>]

From: Dmitry Baryshkov <dmitry.baryshkov@linaro.org>

[ Upstream commit 5e8436d334ed7f6785416447c50b42077c6503e0 ]

Reading access to connector->eld can happen at the same time the
drm_edid_to_eld() updates the data. Take the newly added eld_mutex in
order to protect connector->eld from concurrent access.

Reviewed-by: Maxime Ripard <mripard@kernel.org>
Link: https://patchwork.freedesktop.org/patch/msgid/20241206-drm-connector-eld-mutex-v2-5-c9bce1ee8bea@linaro.org
Signed-off-by: Dmitry Baryshkov <dmitry.baryshkov@linaro.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
---
 drivers/gpu/drm/exynos/exynos_hdmi.c | 2 ++
 1 file changed, 2 insertions(+)

diff --git a/drivers/gpu/drm/exynos/exynos_hdmi.c b/drivers/gpu/drm/exynos/exynos_hdmi.c
index 1e26cd4f83479..52059cfff4f0b 100644
--- a/drivers/gpu/drm/exynos/exynos_hdmi.c
+++ b/drivers/gpu/drm/exynos/exynos_hdmi.c
@@ -1643,7 +1643,9 @@ static int hdmi_audio_get_eld(struct device *dev, void *data, uint8_t *buf,
 	struct hdmi_context *hdata = dev_get_drvdata(dev);
 	struct drm_connector *connector = &hdata->connector;
 
+	mutex_lock(&connector->eld_mutex);
 	memcpy(buf, connector->eld, min(sizeof(connector->eld), len));
+	mutex_unlock(&connector->eld_mutex);
 
 	return 0;
 }
-- 
2.39.5