[PATCH] drm/bridge: Add missing pm_runtime_put_sync

From: Yongzhi Liu
Date: Wed Jan 19 2022 - 10:42:14 EST


pm_runtime_get_sync() will increase the rumtime PM counter
even it returns an error. Thus a pairing decrement is needed
to prevent refcount leak. Fix this by replacing this API with
pm_runtime_resume_and_get(), which will not change the runtime
PM counter on error. Besides, a matching decrement is needed
on the error handling path to keep the counter balanced.

Signed-off-by: Yongzhi Liu <lyz_cs@xxxxxxxxxx>
---
drivers/gpu/drm/bridge/nwl-dsi.c | 17 +++++++++++------
1 file changed, 11 insertions(+), 6 deletions(-)

diff --git a/drivers/gpu/drm/bridge/nwl-dsi.c b/drivers/gpu/drm/bridge/nwl-dsi.c
index 9282e61..e7dce5a 100644
--- a/drivers/gpu/drm/bridge/nwl-dsi.c
+++ b/drivers/gpu/drm/bridge/nwl-dsi.c
@@ -862,18 +862,19 @@ nwl_dsi_bridge_mode_set(struct drm_bridge *bridge,
memcpy(&dsi->mode, adjusted_mode, sizeof(dsi->mode));
drm_mode_debug_printmodeline(adjusted_mode);

- pm_runtime_get_sync(dev);
+ if (pm_runtime_resume_and_get(dev) < 0)
+ return;

if (clk_prepare_enable(dsi->lcdif_clk) < 0)
- return;
+ goto runtime_put;
if (clk_prepare_enable(dsi->core_clk) < 0)
- return;
+ goto runtime_put;

/* Step 1 from DSI reset-out instructions */
ret = reset_control_deassert(dsi->rst_pclk);
if (ret < 0) {
DRM_DEV_ERROR(dev, "Failed to deassert PCLK: %d\n", ret);
- return;
+ goto runtime_put;
}

/* Step 2 from DSI reset-out instructions */
@@ -883,13 +884,17 @@ nwl_dsi_bridge_mode_set(struct drm_bridge *bridge,
ret = reset_control_deassert(dsi->rst_esc);
if (ret < 0) {
DRM_DEV_ERROR(dev, "Failed to deassert ESC: %d\n", ret);
- return;
+ goto runtime_put;
}
ret = reset_control_deassert(dsi->rst_byte);
if (ret < 0) {
DRM_DEV_ERROR(dev, "Failed to deassert BYTE: %d\n", ret);
- return;
+ goto runtime_put;
}
+
+runtime_put:
+ pm_runtime_put_sync(dev);
+ return;
}

static void
--
2.7.4