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

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

From: Lin Huang hl@rock-chips.com

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

Reviewed-by: Archit Taneja architt@codeaurora.org

Thanks, Archit

Cc: Kristian H. Kristensen hoegsberg@chromium.org Signed-off-by: Lin Huang hl@rock-chips.com Signed-off-by: zain wang wzz@rock-chips.com Signed-off-by: Douglas Anderson dianders@chromium.org Signed-off-by: Sean Paul seanpaul@chromium.org Signed-off-by: Thierry Escande thierry.escande@collabora.com Reviewed-by: Andrzej Hajda a.hajda@samsung.com Signed-off-by: Enric Balletbo i Serra enric.balletbo@collabora.com Tested-by: Marek Szyprowski m.szyprowski@samsung.com

---

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(&dp->aux, DP_PSR_SUPPORT, &psr_version);
• if (ret != 1) {

• dev_err(dp->dev, "failed to get PSR version, disable it\n");
  

• return ret;
  

• }

• drm_dp_dpcd_readb(&dp->aux, DP_PSR_SUPPORT, &psr_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(&dp->aux, DP_PSR_EN_CFG, &psr_en);

• ret = drm_dp_dpcd_readb(&dp->aux, DP_PSR_EN_CFG, &psr_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(&dp->aux, DP_PSR_EN_CFG, psr_en);

• ret = drm_dp_dpcd_writeb(&dp->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(&dp->aux, DP_PSR_EN_CFG, psr_en);

• ret = drm_dp_dpcd_writeb(&dp->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(&dp->aux, DP_PSR_EN_CFG, psr_en);

• ret = drm_dp_dpcd_writeb(&dp->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(&dp->aux, DP_LANE_COUNT_SET, &data);

• ret = drm_dp_dpcd_readb(&dp->aux, DP_LANE_COUNT_SET, &data);

• if (ret != 1)

• return ret;
  
  

  if (enable)

• drm_dp_dpcd_writeb(&dp->aux, DP_LANE_COUNT_SET,
  

• 		   DP_LANE_COUNT_ENHANCED_FRAME_EN |
  

• 			DPCD_LANE_COUNT_SET(data));
  

• ret = drm_dp_dpcd_writeb(&dp->aux, DP_LANE_COUNT_SET,
  

• 			 DP_LANE_COUNT_ENHANCED_FRAME_EN |
  

• 			 DPCD_LANE_COUNT_SET(data));
  

  else

• drm_dp_dpcd_writeb(&dp->aux, DP_LANE_COUNT_SET,
  

• 		   DPCD_LANE_COUNT_SET(data));
  

• ret = drm_dp_dpcd_writeb(&dp->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(&dp->aux, DP_MAX_LANE_COUNT, &data);
• retval = DPCD_ENHANCED_FRAME_CAP(data);

• ret = drm_dp_dpcd_readb(&dp->aux, DP_MAX_LANE_COUNT, &data);
• if (ret != 1) {

• *enhanced_mode_support = 0;
  

• return ret;
  

• }

• return retval;

• *enhanced_mode_support = DPCD_ENHANCED_FRAME_CAP(data);
• return 0; }

-static void analogix_dp_set_enhanced_mode(struct analogix_dp_device *dp) +static int analogix_dp_set_enhanced_mode(struct analogix_dp_device *dp) { u8 data;

• int ret;
• ret = analogix_dp_is_enhanced_mode_available(dp, &data);
• if (ret < 0)

• return ret;
  

• ret = analogix_dp_enable_rx_to_enhanced_mode(dp, data);
• if (ret < 0)

• return ret;
  
  

• data = analogix_dp_is_enhanced_mode_available(dp);
• analogix_dp_enable_rx_to_enhanced_mode(dp, data); analogix_dp_enable_enhanced_mode(dp, data);

• return 0; }

-static void analogix_dp_training_pattern_dis(struct analogix_dp_device *dp) +static int analogix_dp_training_pattern_dis(struct analogix_dp_device *dp) {

• int ret;
• analogix_dp_set_training_pattern(dp, DP_NONE);

• drm_dp_dpcd_writeb(&dp->aux, DP_TRAINING_PATTERN_SET,

• 	   DP_TRAINING_PATTERN_DISABLE);
  

• ret = drm_dp_dpcd_writeb(&dp->aux, DP_TRAINING_PATTERN_SET,

• 		 DP_TRAINING_PATTERN_DISABLE);
  

• return ret < 0 ? ret : 0; }

  static void

@@ -282,7 +339,11 @@ static int analogix_dp_link_start(struct analogix_dp_device *dp) if (retval < 0) return retval; /* set enhanced mode if available */

• analogix_dp_set_enhanced_mode(dp);

• retval = analogix_dp_set_enhanced_mode(dp);

• if (retval < 0) {

• dev_err(dp->dev, "failed to set enhance mode\n");
  

• return retval;
  

• }

  /* Set TX pre-emphasis to minimum */ for (lane = 0; lane < lane_count; lane++)

@@ -567,10 +628,11 @@ static int analogix_dp_process_equalizer_training(struct analogix_dp_device *dp)

if (!analogix_dp_channel_eq_ok(link_status, link_align, lane_count)) { /* traing pattern Set to Normal */

• analogix_dp_training_pattern_dis(dp);
  

• retval = analogix_dp_training_pattern_dis(dp);
  

• if (retval < 0)
  

• 	return retval;
  
  

  dev_info(dp->dev, "Link Training success!\n");

• analogix_dp_get_link_bandwidth(dp, &reg); dp->link_train.link_rate = reg; dev_dbg(dp->dev, "final bandwidth = %.2x\n",

@@ -867,24 +929,32 @@ static int analogix_dp_config_video(struct analogix_dp_device *dp) return 0; }

-static void analogix_dp_enable_scramble(struct analogix_dp_device *dp,

• 			bool enable)
  

+static int analogix_dp_enable_scramble(struct analogix_dp_device *dp,

• 		       bool enable)
  

  { u8 data;

• int ret;

  if (enable) { analogix_dp_enable_scrambling(dp);

• drm_dp_dpcd_readb(&dp->aux, DP_TRAINING_PATTERN_SET, &data);
  

• drm_dp_dpcd_writeb(&dp->aux, DP_TRAINING_PATTERN_SET,
  

• ret = drm_dp_dpcd_readb(&dp->aux, DP_TRAINING_PATTERN_SET,
  

• 			&data);
  

• if (ret != 1)
  

• 	return ret;
  

• ret = drm_dp_dpcd_writeb(&dp->aux, DP_TRAINING_PATTERN_SET,
  	   (u8)(data & ~DP_LINK_SCRAMBLING_DISABLE));
  

  } else { analogix_dp_disable_scrambling(dp);

• drm_dp_dpcd_readb(&dp->aux, DP_TRAINING_PATTERN_SET, &data);
  

• drm_dp_dpcd_writeb(&dp->aux, DP_TRAINING_PATTERN_SET,
  

• ret = drm_dp_dpcd_readb(&dp->aux, DP_TRAINING_PATTERN_SET,
  

• 			&data);
  

• if (ret != 1)
  

• 	return ret;
  

• ret = drm_dp_dpcd_writeb(&dp->aux, DP_TRAINING_PATTERN_SET,
  	   (u8)(data | DP_LINK_SCRAMBLING_DISABLE));
  

  }

• return ret < 0 ? ret : 0; }

  static irqreturn_t analogix_dp_hardirq(int irq, void *arg)

@@ -939,23 +1009,36 @@ static int analogix_dp_commit(struct analogix_dp_device *dp) return ret; }

• analogix_dp_enable_scramble(dp, 1);

• ret = analogix_dp_enable_scramble(dp, 1);

• if (ret < 0) {

• dev_err(dp->dev, "can not enable scramble\n");
  

• return ret;
  

• }

  analogix_dp_init_video(dp); ret = analogix_dp_config_video(dp);

• if (ret)

• if (ret) { dev_err(dp->dev, "unable to config video\n");

• return ret;
  

• }

  /* Safe to enable the panel now */ if (dp->plat_data->panel) {

• if (drm_panel_enable(dp->plat_data->panel))
  

• ret = drm_panel_enable(dp->plat_data->panel);
  

• if (ret) {
  DRM_ERROR("failed to enable the panel\n");
  

• 	return ret;
  

• }
  

  }

• dp->psr_enable = analogix_dp_detect_sink_psr(dp);

• ret = analogix_dp_detect_sink_psr(dp);
• if (ret)

• return ret;
  

• if (dp->psr_enable)

• analogix_dp_enable_sink_psr(dp);
  

• return 0;

• ret = analogix_dp_enable_sink_psr(dp);
  

• return ret; }

  /*

@@ -1185,8 +1268,10 @@ static int analogix_dp_set_bridge(struct analogix_dp_device *dp) }

ret = analogix_dp_commit(dp);

• if (ret)

• if (ret) {

• DRM_ERROR("dp commit error, ret = %d\n", ret);
  

  goto out_dp_init;

• }

  enable_irq(dp->irq); return 0;