pm_runtime_get_sync() will increase the rumtime PM counter even when 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@pku.edu.cn --- drivers/gpu/drm/bridge/nwl-dsi.c | 18 ++++++++++++------ 1 file changed, 12 insertions(+), 6 deletions(-)

diff --git a/drivers/gpu/drm/bridge/nwl-dsi.c b/drivers/gpu/drm/bridge/nwl-dsi.c index 9282e61..30aacd9 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 +884,18 @@ 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; } + + return; + +runtime_put: + pm_runtime_put_sync(dev); }

static void

On Thu, 27 Jan 2022 at 02:10, Laurent Pinchart laurent.pinchart@ideasonboard.com wrote:

Hi Yongzhi,

Thank you for the patch.

On Sun, Jan 23, 2022 at 11:20:35PM -0800, Yongzhi Liu wrote:

...

pm_runtime_get_sync() will increase the rumtime PM counter even when 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@pku.edu.cn

Reviewed-by: Laurent Pinchart laurent.pinchart@ideasonboard.com

...

---

drivers/gpu/drm/bridge/nwl-dsi.c | 18 ++++++++++++------ 1 file changed, 12 insertions(+), 6 deletions(-)

diff --git a/drivers/gpu/drm/bridge/nwl-dsi.c b/drivers/gpu/drm/bridge/nwl-dsi.c index 9282e61..30aacd9 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 +884,18 @@ 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;
  }
  

• return;
  

+runtime_put:

• pm_runtime_put_sync(dev);
  

}

static void

Applied to drm-misc-next.