drm/bridge: dw-hdmi: fix SCDC configuration for ddc-i2c-bus

[linux.git] / drivers / gpu / drm / bridge / synopsys / dw-hdmi.c

diff --git a/drivers/gpu/drm/bridge/synopsys/dw-hdmi.c b/drivers/gpu/drm/bridge/synopsys/dw-hdmi.c
index a63e5f0dae56ad3de5a372ecd167a350d5b89457..ab7968c8f6a29937177c0a464f6da4db9e297631 100644 (file)
--- a/drivers/gpu/drm/bridge/synopsys/dw-hdmi.c
+++ b/drivers/gpu/drm/bridge/synopsys/dw-hdmi.c
@@ -1037,6 +1037,35 @@ void dw_hdmi_phy_i2c_write(struct dw_hdmi *hdmi, unsigned short data,
 }
 EXPORT_SYMBOL_GPL(dw_hdmi_phy_i2c_write);
 
+/* Filter out invalid setups to avoid configuring SCDC and scrambling */
+static bool dw_hdmi_support_scdc(struct dw_hdmi *hdmi)
+{
+       struct drm_display_info *display = &hdmi->connector.display_info;
+
+       /* Completely disable SCDC support for older controllers */
+       if (hdmi->version < 0x200a)
+               return false;
+
+       /* Disable if no DDC bus */
+       if (!hdmi->ddc)
+               return false;
+
+       /* Disable if SCDC is not supported, or if an HF-VSDB block is absent */
+       if (!display->hdmi.scdc.supported ||
+           !display->hdmi.scdc.scrambling.supported)
+               return false;
+
+       /*
+        * Disable if display only support low TMDS rates and scrambling
+        * for low rates is not supported either
+        */
+       if (!display->hdmi.scdc.scrambling.low_rates &&
+           display->max_tmds_clock <= 340000)
+               return false;
+
+       return true;
+}
+
 /*
  * HDMI2.0 Specifies the following procedure for High TMDS Bit Rates:
  * - The Source shall suspend transmission of the TMDS clock and data
@@ -1055,7 +1084,7 @@ void dw_hdmi_set_high_tmds_clock_ratio(struct dw_hdmi *hdmi)
        unsigned long mtmdsclock = hdmi->hdmi_data.video_mode.mtmdsclock;
 
        /* Control for TMDS Bit Period/TMDS Clock-Period Ratio */
-       if (hdmi->connector.display_info.hdmi.scdc.supported) {
+       if (dw_hdmi_support_scdc(hdmi)) {
                if (mtmdsclock > HDMI14_MAX_TMDSCLK)
                        drm_scdc_set_high_tmds_clock_ratio(hdmi->ddc, 1);
                else
@@ -1579,8 +1608,9 @@ static void hdmi_av_composer(struct dw_hdmi *hdmi,
 
        /* Set up HDMI_FC_INVIDCONF */
        inv_val = (hdmi->hdmi_data.hdcp_enable ||
-                  vmode->mtmdsclock > HDMI14_MAX_TMDSCLK ||
-                  hdmi_info->scdc.scrambling.low_rates ?
+                  (dw_hdmi_support_scdc(hdmi) &&
+                   (vmode->mtmdsclock > HDMI14_MAX_TMDSCLK ||
+                    hdmi_info->scdc.scrambling.low_rates)) ?
                HDMI_FC_INVIDCONF_HDCP_KEEPOUT_ACTIVE :
                HDMI_FC_INVIDCONF_HDCP_KEEPOUT_INACTIVE);
 
@@ -1646,7 +1676,7 @@ static void hdmi_av_composer(struct dw_hdmi *hdmi,
        }
 
        /* Scrambling Control */
-       if (hdmi_info->scdc.supported) {
+       if (dw_hdmi_support_scdc(hdmi)) {
                if (vmode->mtmdsclock > HDMI14_MAX_TMDSCLK ||
                    hdmi_info->scdc.scrambling.low_rates) {
                        /*
@@ -1658,13 +1688,13 @@ static void hdmi_av_composer(struct dw_hdmi *hdmi,
                         * Source Devices compliant shall set the
                         * Source Version = 1.
                         */
-                       drm_scdc_readb(&hdmi->i2c->adap, SCDC_SINK_VERSION,
+                       drm_scdc_readb(hdmi->ddc, SCDC_SINK_VERSION,
                                       &bytes);
-                       drm_scdc_writeb(&hdmi->i2c->adap, SCDC_SOURCE_VERSION,
+                       drm_scdc_writeb(hdmi->ddc, SCDC_SOURCE_VERSION,
                                min_t(u8, bytes, SCDC_MIN_SOURCE_VERSION));
 
                        /* Enabled Scrambling in the Sink */
-                       drm_scdc_set_scrambling(&hdmi->i2c->adap, 1);
+                       drm_scdc_set_scrambling(hdmi->ddc, 1);
 
                        /*
                         * To activate the scrambler feature, you must ensure
@@ -1680,7 +1710,7 @@ static void hdmi_av_composer(struct dw_hdmi *hdmi,
                        hdmi_writeb(hdmi, 0, HDMI_FC_SCRAMBLER_CTRL);
                        hdmi_writeb(hdmi, (u8)~HDMI_MC_SWRSTZ_TMDSSWRST_REQ,
                                    HDMI_MC_SWRSTZ);
-                       drm_scdc_set_scrambling(&hdmi->i2c->adap, 0);
+                       drm_scdc_set_scrambling(hdmi->ddc, 0);
                }
        }
 
@@ -1774,6 +1804,8 @@ static void dw_hdmi_clear_overflow(struct dw_hdmi *hdmi)
         * iteration for others.
         * The Amlogic Meson GX SoCs (v2.01a) have been identified as needing
         * the workaround with a single iteration.
+        * The Rockchip RK3288 SoC (v2.00a) and RK3328/RK3399 SoCs (v2.11a) have
+        * been identified as needing the workaround with a single iteration.
         */
 
        switch (hdmi->version) {
@@ -1782,7 +1814,9 @@ static void dw_hdmi_clear_overflow(struct dw_hdmi *hdmi)
                break;
        case 0x131a:
        case 0x132a:
+       case 0x200a:
        case 0x201a:
+       case 0x211a:
        case 0x212a:
                count = 1;
                break;