drm/i915: Initialize the SDVO device based on the sdvo info parsed from VBT

http://bugs.freedesktop.org/show_bug.cgi?id=20429

Signed-off-by: Zhao Yakui <yakui.zhao@intel.com>
[anholt: Massive cleanup of the slave addr function]
Signed-off-by: Eric Anholt <eric@anholt.net>

1 files changed, 40 insertions, 3 deletions

diff --git a/drivers/gpu/drm/i915/intel_sdvo.c b/drivers/gpu/drm/i915/intel_sdvo.c
index f3ef6bfd8ffc..d8fb88d335cd 100644
--- a/drivers/gpu/drm/i915/intel_sdvo.c
+++ b/drivers/gpu/drm/i915/intel_sdvo.c
@@ -1741,6 +1741,43 @@ static struct i2c_algorithm intel_sdvo_i2c_bit_algo = {
         .master_xfer    = intel_sdvo_master_xfer,
 };
 
+static u8
+intel_sdvo_get_slave_addr(struct drm_device *dev, int output_device)
+{
+        struct drm_i915_private *dev_priv = dev->dev_private;
+        struct sdvo_device_mapping *my_mapping, *other_mapping;
+
+        if (output_device == SDVOB) {
+                my_mapping = &dev_priv->sdvo_mappings[0];
+                other_mapping = &dev_priv->sdvo_mappings[1];
+        } else {
+                my_mapping = &dev_priv->sdvo_mappings[1];
+                other_mapping = &dev_priv->sdvo_mappings[0];
+        }
+
+        /* If the BIOS described our SDVO device, take advantage of it. */
+        if (my_mapping->slave_addr)
+                return my_mapping->slave_addr;
+
+        /* If the BIOS only described a different SDVO device, use the
+         * address that it isn't using.
+         */
+        if (other_mapping->slave_addr) {
+                if (other_mapping->slave_addr == 0x70)
+                        return 0x72;
+                else
+                        return 0x70;
+        }
+
+        /* No SDVO device info is found for another DVO port,
+         * so use mapping assumption we had before BIOS parsing.
+         */
+        if (output_device == SDVOB)
+                return 0x70;
+        else
+                return 0x72;
+}
+
 bool intel_sdvo_init(struct drm_device *dev, int output_device)
 {
         struct drm_connector *connector;
@@ -1752,6 +1789,7 @@ bool intel_sdvo_init(struct drm_device *dev, int output_device)
         u8 ch[0x40];
         int i;
         int encoder_type, output_id;
+        u8 slave_addr;
 
         intel_output = kcalloc(sizeof(struct intel_output)+sizeof(struct intel_sdvo_priv), 1, GFP_KERNEL);
         if (!intel_output) {
@@ -1770,16 +1808,15 @@ bool intel_sdvo_init(struct drm_device *dev, int output_device)
         if (!i2cbus)
                 goto err_inteloutput;
 
+        slave_addr = intel_sdvo_get_slave_addr(dev, output_device);
         sdvo_priv->i2c_bus = i2cbus;
 
         if (output_device == SDVOB) {
                 output_id = 1;
-                sdvo_priv->i2c_bus->slave_addr = 0x38;
         } else {
                 output_id = 2;
-                sdvo_priv->i2c_bus->slave_addr = 0x39;
         }
-
+        sdvo_priv->i2c_bus->slave_addr = slave_addr >> 1;
         sdvo_priv->output_device = output_device;
         intel_output->i2c_bus = i2cbus;
         intel_output->dev_priv = sdvo_priv;