Re: [PATCH v5 16/36] drm/bridge: analogix_dp: Check dpcd write/read status

[Archit Taneja]

On Saturday 10 March 2018 03:53 AM, Enric Balletbo i Serra wrote:

From: Lin Huang 

We need to check the dpcd write/read return value to see whether the
write/read was successful



Reviewed-by: Archit Taneja 

Thanks,
Archit


Cc: Kristian H. Kristensen 
Signed-off-by: Lin Huang 
Signed-off-by: zain wang 
Signed-off-by: Douglas Anderson 
Signed-off-by: Sean Paul 
Signed-off-by: Thierry Escande 
Reviewed-by: Andrzej Hajda 
Signed-off-by: Enric Balletbo i Serra 
Tested-by: Marek Szyprowski 
---

  drivers/gpu/drm/bridge/analogix/analogix_dp_core.c | 169 -
  1 file changed, 127 insertions(+), 42 deletions(-)

diff --git a/drivers/gpu/drm/bridge/analogix/analogix_dp_core.c 
b/drivers/gpu/drm/bridge/analogix/analogix_dp_core.c
index 1eed35f9eb8d..be6eddd0d0a7 100644
--- a/drivers/gpu/drm/bridge/analogix/analogix_dp_core.c
+++ b/drivers/gpu/drm/bridge/analogix/analogix_dp_core.c
@@ -160,80 +160,137 @@ int analogix_dp_disable_psr(struct analogix_dp_device 
*dp)
  }
  EXPORT_SYMBOL_GPL(analogix_dp_disable_psr);
  
-static bool analogix_dp_detect_sink_psr(struct analogix_dp_device *dp)

+static int analogix_dp_detect_sink_psr(struct analogix_dp_device *dp)
  {
unsigned char psr_version;
+   int ret;
+
+   ret = drm_dp_dpcd_readb(>aux, DP_PSR_SUPPORT, _version);
+   if (ret != 1) {
+   dev_err(dp->dev, "failed to get PSR version, disable it\n");
+   return ret;
+   }
  
-	drm_dp_dpcd_readb(>aux, DP_PSR_SUPPORT, _version);

dev_dbg(dp->dev, "Panel PSR version : %x\n", psr_version);
  
-	return (psr_version & DP_PSR_IS_SUPPORTED) ? true : false;

+   dp->psr_enable = (psr_version & DP_PSR_IS_SUPPORTED) ? true : false;
+
+   return 0;
  }
  
-static void analogix_dp_enable_sink_psr(struct analogix_dp_device *dp)

+static int analogix_dp_enable_sink_psr(struct analogix_dp_device *dp)
  {
unsigned char psr_en;
+   int ret;
  
  	/* Disable psr function */

-   drm_dp_dpcd_readb(>aux, DP_PSR_EN_CFG, _en);
+   ret = drm_dp_dpcd_readb(>aux, DP_PSR_EN_CFG, _en);
+   if (ret != 1) {
+   dev_err(dp->dev, "failed to get psr config\n");
+   goto end;
+   }
+
psr_en &= ~DP_PSR_ENABLE;
-   drm_dp_dpcd_writeb(>aux, DP_PSR_EN_CFG, psr_en);
+   ret = drm_dp_dpcd_writeb(>aux, DP_PSR_EN_CFG, psr_en);
+   if (ret != 1) {
+   dev_err(dp->dev, "failed to disable panel psr\n");
+   goto end;
+   }
  
  	/* Main-Link transmitter remains active during PSR active states */

psr_en = DP_PSR_MAIN_LINK_ACTIVE | DP_PSR_CRC_VERIFICATION;
-   drm_dp_dpcd_writeb(>aux, DP_PSR_EN_CFG, psr_en);
+   ret = drm_dp_dpcd_writeb(>aux, DP_PSR_EN_CFG, psr_en);
+   if (ret != 1) {
+   dev_err(dp->dev, "failed to set panel psr\n");
+   goto end;
+   }
  
  	/* Enable psr function */

psr_en = DP_PSR_ENABLE | DP_PSR_MAIN_LINK_ACTIVE |
 DP_PSR_CRC_VERIFICATION;
-   drm_dp_dpcd_writeb(>aux, DP_PSR_EN_CFG, psr_en);
+   ret = drm_dp_dpcd_writeb(>aux, DP_PSR_EN_CFG, psr_en);
+   if (ret != 1) {
+   dev_err(dp->dev, "failed to set panel psr\n");
+   goto end;
+   }
  
  	analogix_dp_enable_psr_crc(dp);

+
+   return 0;
+end:
+   dev_err(dp->dev, "enable psr fail, force to disable psr\n");
+   dp->psr_enable = false;
+
+   return ret;
  }
  
-static void

+static int
  analogix_dp_enable_rx_to_enhanced_mode(struct analogix_dp_device *dp,
   bool enable)
  {
u8 data;
+   int ret;
  
-	drm_dp_dpcd_readb(>aux, DP_LANE_COUNT_SET, );

+   ret = drm_dp_dpcd_readb(>aux, DP_LANE_COUNT_SET, );
+   if (ret != 1)
+   return ret;
  
  	if (enable)

-   drm_dp_dpcd_writeb(>aux, DP_LANE_COUNT_SET,
-  DP_LANE_COUNT_ENHANCED_FRAME_EN |
-   DPCD_LANE_COUNT_SET(data));
+   ret = drm_dp_dpcd_writeb(>aux, DP_LANE_COUNT_SET,
+DP_LANE_COUNT_ENHANCED_FRAME_EN |
+DPCD_LANE_COUNT_SET(data));
else
-   drm_dp_dpcd_writeb(>aux, DP_LANE_COUNT_SET,
-  DPCD_LANE_COUNT_SET(data));
+   ret = drm_dp_dpcd_writeb(>aux, DP_LANE_COUNT_SET,
+DPCD_LANE_COUNT_SET(data));
+
+   return ret < 0 ? ret : 0;
  }
  
-static int analogix_dp_is_enhanced_mode_available(struct analogix_dp_device *dp)

+static int analogix_dp_is_enhanced_mode_available(struct analogix_dp_device 
*dp,
+ 

Re: [PATCH v5 16/36] drm/bridge: analogix_dp: Check dpcd write/read status

[Archit Taneja]

On Saturday 10 March 2018 03:53 AM, Enric Balletbo i Serra wrote:

From: Lin Huang 

We need to check the dpcd write/read return value to see whether the
write/read was successful



Reviewed-by: Archit Taneja 

Thanks,
Archit


Cc: Kristian H. Kristensen 
Signed-off-by: Lin Huang 
Signed-off-by: zain wang 
Signed-off-by: Douglas Anderson 
Signed-off-by: Sean Paul 
Signed-off-by: Thierry Escande 
Reviewed-by: Andrzej Hajda 
Signed-off-by: Enric Balletbo i Serra 
Tested-by: Marek Szyprowski 
---

  drivers/gpu/drm/bridge/analogix/analogix_dp_core.c | 169 -
  1 file changed, 127 insertions(+), 42 deletions(-)

diff --git a/drivers/gpu/drm/bridge/analogix/analogix_dp_core.c 
b/drivers/gpu/drm/bridge/analogix/analogix_dp_core.c
index 1eed35f9eb8d..be6eddd0d0a7 100644
--- a/drivers/gpu/drm/bridge/analogix/analogix_dp_core.c
+++ b/drivers/gpu/drm/bridge/analogix/analogix_dp_core.c
@@ -160,80 +160,137 @@ int analogix_dp_disable_psr(struct analogix_dp_device 
*dp)
  }
  EXPORT_SYMBOL_GPL(analogix_dp_disable_psr);
  
-static bool analogix_dp_detect_sink_psr(struct analogix_dp_device *dp)

+static int analogix_dp_detect_sink_psr(struct analogix_dp_device *dp)
  {
unsigned char psr_version;
+   int ret;
+
+   ret = drm_dp_dpcd_readb(>aux, DP_PSR_SUPPORT, _version);
+   if (ret != 1) {
+   dev_err(dp->dev, "failed to get PSR version, disable it\n");
+   return ret;
+   }
  
-	drm_dp_dpcd_readb(>aux, DP_PSR_SUPPORT, _version);

dev_dbg(dp->dev, "Panel PSR version : %x\n", psr_version);
  
-	return (psr_version & DP_PSR_IS_SUPPORTED) ? true : false;

+   dp->psr_enable = (psr_version & DP_PSR_IS_SUPPORTED) ? true : false;
+
+   return 0;
  }
  
-static void analogix_dp_enable_sink_psr(struct analogix_dp_device *dp)

+static int analogix_dp_enable_sink_psr(struct analogix_dp_device *dp)
  {
unsigned char psr_en;
+   int ret;
  
  	/* Disable psr function */

-   drm_dp_dpcd_readb(>aux, DP_PSR_EN_CFG, _en);
+   ret = drm_dp_dpcd_readb(>aux, DP_PSR_EN_CFG, _en);
+   if (ret != 1) {
+   dev_err(dp->dev, "failed to get psr config\n");
+   goto end;
+   }
+
psr_en &= ~DP_PSR_ENABLE;
-   drm_dp_dpcd_writeb(>aux, DP_PSR_EN_CFG, psr_en);
+   ret = drm_dp_dpcd_writeb(>aux, DP_PSR_EN_CFG, psr_en);
+   if (ret != 1) {
+   dev_err(dp->dev, "failed to disable panel psr\n");
+   goto end;
+   }
  
  	/* Main-Link transmitter remains active during PSR active states */

psr_en = DP_PSR_MAIN_LINK_ACTIVE | DP_PSR_CRC_VERIFICATION;
-   drm_dp_dpcd_writeb(>aux, DP_PSR_EN_CFG, psr_en);
+   ret = drm_dp_dpcd_writeb(>aux, DP_PSR_EN_CFG, psr_en);
+   if (ret != 1) {
+   dev_err(dp->dev, "failed to set panel psr\n");
+   goto end;
+   }
  
  	/* Enable psr function */

psr_en = DP_PSR_ENABLE | DP_PSR_MAIN_LINK_ACTIVE |
 DP_PSR_CRC_VERIFICATION;
-   drm_dp_dpcd_writeb(>aux, DP_PSR_EN_CFG, psr_en);
+   ret = drm_dp_dpcd_writeb(>aux, DP_PSR_EN_CFG, psr_en);
+   if (ret != 1) {
+   dev_err(dp->dev, "failed to set panel psr\n");
+   goto end;
+   }
  
  	analogix_dp_enable_psr_crc(dp);

+
+   return 0;
+end:
+   dev_err(dp->dev, "enable psr fail, force to disable psr\n");
+   dp->psr_enable = false;
+
+   return ret;
  }
  
-static void

+static int
  analogix_dp_enable_rx_to_enhanced_mode(struct analogix_dp_device *dp,
   bool enable)
  {
u8 data;
+   int ret;
  
-	drm_dp_dpcd_readb(>aux, DP_LANE_COUNT_SET, );

+   ret = drm_dp_dpcd_readb(>aux, DP_LANE_COUNT_SET, );
+   if (ret != 1)
+   return ret;
  
  	if (enable)

-   drm_dp_dpcd_writeb(>aux, DP_LANE_COUNT_SET,
-  DP_LANE_COUNT_ENHANCED_FRAME_EN |
-   DPCD_LANE_COUNT_SET(data));
+   ret = drm_dp_dpcd_writeb(>aux, DP_LANE_COUNT_SET,
+DP_LANE_COUNT_ENHANCED_FRAME_EN |
+DPCD_LANE_COUNT_SET(data));
else
-   drm_dp_dpcd_writeb(>aux, DP_LANE_COUNT_SET,
-  DPCD_LANE_COUNT_SET(data));
+   ret = drm_dp_dpcd_writeb(>aux, DP_LANE_COUNT_SET,
+DPCD_LANE_COUNT_SET(data));
+
+   return ret < 0 ? ret : 0;
  }
  
-static int analogix_dp_is_enhanced_mode_available(struct analogix_dp_device *dp)

+static int analogix_dp_is_enhanced_mode_available(struct analogix_dp_device 
*dp,
+ u8 *enhanced_mode_support)
  {
u8 data;
-   int retval;
+   int ret;
  
-	drm_dp_dpcd_readb(>aux, DP_MAX_LANE_COUNT, );

-   retval = DPCD_ENHANCED_FRAME_CAP(data);
+   ret = drm_dp_dpcd_readb(>aux,