drm/i915/bios: filter out invalid DDC pins from VBT child devices

[mirror_ubuntu-artful-kernel.git] / drivers / gpu / drm / i915 / intel_bios.c

diff --git a/drivers/gpu/drm/i915/intel_bios.c b/drivers/gpu/drm/i915/intel_bios.c
index 639d45c1dd2e6ac24013431aa6da84abb9f0b089..3250acb1b2877ecf8cbdf92add7b02011c774d56 100644 (file)
--- a/drivers/gpu/drm/i915/intel_bios.c
+++ b/drivers/gpu/drm/i915/intel_bios.c
@@ -29,6 +29,7 @@
 #include <drm/drmP.h>
 #include <drm/i915_drm.h>
 #include "i915_drv.h"
+#include <linux/dmi.h>
 
 #define _INTEL_BIOS_PRIVATE
 #include "intel_vbt_defs.h"
@@ -1120,8 +1121,8 @@ static void parse_ddi_port(struct drm_i915_private *dev_priv, enum port port,
        bool is_dvi, is_hdmi, is_dp, is_edp, is_crt;
        uint8_t aux_channel, ddc_pin;
        /* Each DDI port can have more than one value on the "DVO Port" field,
-        * so look for all the possible values for each port and abort if more
-        * than one is found. */
+        * so look for all the possible values for each port.
+        */
        int dvo_ports[][3] = {
                {DVO_PORT_HDMIA, DVO_PORT_DPA, -1},
                {DVO_PORT_HDMIB, DVO_PORT_DPB, -1},
@@ -1130,7 +1131,10 @@ static void parse_ddi_port(struct drm_i915_private *dev_priv, enum port port,
                {DVO_PORT_CRT, DVO_PORT_HDMIE, DVO_PORT_DPE},
        };
 
-       /* Find the child device to use, abort if more than one found. */
+       /*
+        * Find the first child device to reference the port, report if more
+        * than one found.
+        */
        for (i = 0; i < dev_priv->vbt.child_dev_num; i++) {
                it = dev_priv->vbt.child_dev + i;
 
@@ -1140,11 +1144,11 @@ static void parse_ddi_port(struct drm_i915_private *dev_priv, enum port port,
 
                        if (it->common.dvo_port == dvo_ports[port][j]) {
                                if (child) {
-                                       DRM_DEBUG_KMS("More than one child device for port %c in VBT.\n",
+                                       DRM_DEBUG_KMS("More than one child device for port %c in VBT, using the first.\n",
                                                      port_name(port));
-                                       return;
+                               } else {
+                                       child = it;
                                }
-                               child = it;
                        }
                }
        }
@@ -1152,7 +1156,6 @@ static void parse_ddi_port(struct drm_i915_private *dev_priv, enum port port,
                return;
 
        aux_channel = child->common.aux_channel;
-       ddc_pin = child->common.ddc_pin;
 
        is_dvi = child->common.device_type & DEVICE_TYPE_TMDS_DVI_SIGNALING;
        is_dp = child->common.device_type & DEVICE_TYPE_DISPLAYPORT_OUTPUT;
@@ -1160,6 +1163,13 @@ static void parse_ddi_port(struct drm_i915_private *dev_priv, enum port port,
        is_hdmi = is_dvi && (child->common.device_type & DEVICE_TYPE_NOT_HDMI_OUTPUT) == 0;
        is_edp = is_dp && (child->common.device_type & DEVICE_TYPE_INTERNAL_CONNECTOR);
 
+       if (port == PORT_A && is_dvi) {
+               DRM_DEBUG_KMS("VBT claims port A supports DVI%s, ignoring\n",
+                             is_hdmi ? "/HDMI" : "");
+               is_dvi = false;
+               is_hdmi = false;
+       }
+
        info->supports_dvi = is_dvi;
        info->supports_hdmi = is_hdmi;
        info->supports_dp = is_dp;
@@ -1185,9 +1195,15 @@ static void parse_ddi_port(struct drm_i915_private *dev_priv, enum port port,
                DRM_DEBUG_KMS("Port %c is internal DP\n", port_name(port));
 
        if (is_dvi) {
-               info->alternate_ddc_pin = ddc_pin;
-
-               sanitize_ddc_pin(dev_priv, port);
+               ddc_pin = child->common.ddc_pin;
+               if (intel_gmbus_is_valid_pin(dev_priv, ddc_pin)) {
+                       info->alternate_ddc_pin = ddc_pin;
+                       sanitize_ddc_pin(dev_priv, port);
+               } else {
+                       DRM_DEBUG_KMS("Port %c has invalid DDC pin %d, "
+                                     "sticking to defaults\n",
+                                     port_name(port), ddc_pin);
+               }
        }
 
        if (is_dp) {
@@ -1221,7 +1237,7 @@ static void parse_ddi_ports(struct drm_i915_private *dev_priv,
 {
        enum port port;
 
-       if (!HAS_DDI(dev_priv))
+       if (!HAS_DDI(dev_priv) && !IS_CHERRYVIEW(dev_priv))
                return;
 
        if (!dev_priv->vbt.child_dev_num)
@@ -1471,6 +1487,22 @@ static const struct vbt_header *find_vbt(void __iomem *bios, size_t size)
        return NULL;
 }
 
+#define DRM_DMI_PRODUCT_VERSION 0x6
+
+static void parse_product_info(struct drm_i915_private *dev_priv)
+{
+       const char *product_ver = dmi_get_system_info(DRM_DMI_PRODUCT_VERSION);
+       if (!product_ver)
+               return;
+
+       if (!strncmp(product_ver, "ThinkPad X1", 11)) {
+               DRM_DEBUG_KMS("dmi: %s, Bypassing TMDS_OE write\n", product_ver);
+               dev_priv->bypass_tmds_oe = true;
+       }
+
+       return;
+}
+
 /**
  * intel_bios_init - find VBT and initialize settings from the BIOS
  * @dev_priv: i915 device instance
@@ -1527,6 +1559,7 @@ void intel_bios_init(struct drm_i915_private *dev_priv)
        parse_mipi_config(dev_priv, bdb);
        parse_mipi_sequence(dev_priv, bdb);
        parse_ddi_ports(dev_priv, bdb);
+       parse_product_info(dev_priv);
 
 out:
        if (!vbt) {