drm/i915: use GMBUS to manage i2c links
Use the GMBUS interface rather than direct bit banging to grab the EDID
over DDC (and for other forms of auxiliary communication with external
display controllers). The hope is that this method will be much faster
and more reliable than bit banging for fetching EDIDs from buggy monitors
or through switches, though we still preserve the bit banging as a
fallback in case GMBUS fails.
Based on an original patch by Jesse Barnes.
Cc: Jesse Barnes <jbarnes@virtuousgeek.org>
Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>
diff --git a/drivers/gpu/drm/i915/intel_dvo.c b/drivers/gpu/drm/i915/intel_dvo.c
index d8a586b..1ee0dbb 100644
--- a/drivers/gpu/drm/i915/intel_dvo.c
+++ b/drivers/gpu/drm/i915/intel_dvo.c
@@ -72,7 +72,7 @@
.name = "ch7017",
.dvo_reg = DVOC,
.slave_addr = 0x75,
- .gpio = GPIOE,
+ .gpio = GMBUS_PORT_DPD,
.dev_ops = &ch7017_ops,
}
};
@@ -81,6 +81,7 @@
struct intel_encoder base;
struct intel_dvo_device dev;
+ int ddc_bus;
struct drm_display_mode *panel_fixed_mode;
bool panel_wants_dither;
@@ -235,13 +236,15 @@
static int intel_dvo_get_modes(struct drm_connector *connector)
{
struct intel_dvo *intel_dvo = intel_attached_dvo(connector);
+ struct drm_i915_private *dev_priv = connector->dev->dev_private;
/* We should probably have an i2c driver get_modes function for those
* devices which will have a fixed set of modes determined by the chip
* (TV-out, for example), but for now with just TMDS and LVDS,
* that's not the case.
*/
- intel_ddc_get_modes(connector, intel_dvo->base.ddc_bus);
+ intel_ddc_get_modes(connector,
+ &dev_priv->gmbus[intel_dvo->ddc_bus].adapter);
if (!list_empty(&connector->probed_modes))
return 1;
@@ -341,10 +344,10 @@
void intel_dvo_init(struct drm_device *dev)
{
+ struct drm_i915_private *dev_priv = dev->dev_private;
struct intel_encoder *intel_encoder;
struct intel_dvo *intel_dvo;
struct intel_connector *intel_connector;
- struct i2c_adapter *i2cbus = NULL;
int ret = 0;
int i;
int encoder_type = DRM_MODE_ENCODER_NONE;
@@ -364,15 +367,13 @@
&intel_dvo_enc_funcs, encoder_type);
/* Set up the DDC bus */
- intel_encoder->ddc_bus = intel_i2c_create(intel_encoder,
- GPIOD, "DVODDC_D");
- if (!intel_encoder->ddc_bus)
- goto free_intel;
+ intel_dvo->ddc_bus = GMBUS_PORT_DPB;
/* Now, try to find a controller */
for (i = 0; i < ARRAY_SIZE(intel_dvo_devices); i++) {
struct drm_connector *connector = &intel_connector->base;
const struct intel_dvo_device *dvo = &intel_dvo_devices[i];
+ struct i2c_adapter *i2c;
int gpio;
/* Allow the I2C driver info to specify the GPIO to be used in
@@ -382,23 +383,18 @@
if (dvo->gpio != 0)
gpio = dvo->gpio;
else if (dvo->type == INTEL_DVO_CHIP_LVDS)
- gpio = GPIOB;
+ gpio = GMBUS_PORT_PANEL;
else
- gpio = GPIOE;
+ gpio = GMBUS_PORT_DPD;
/* Set up the I2C bus necessary for the chip we're probing.
* It appears that everything is on GPIOE except for panels
* on i830 laptops, which are on GPIOB (DVOA).
*/
- if (i2cbus != NULL)
- intel_i2c_destroy(i2cbus);
- i2cbus = intel_i2c_create(intel_encoder, gpio,
- gpio == GPIOB ? "DVOI2C_B" : "DVOI2C_E");
- if (i2cbus == NULL)
- continue;
+ i2c = &dev_priv->gmbus[gpio].adapter;
intel_dvo->dev = *dvo;
- ret = dvo->dev_ops->init(&intel_dvo->dev, i2cbus);
+ ret = dvo->dev_ops->init(&intel_dvo->dev, i2c);
if (!ret)
continue;
@@ -451,11 +447,6 @@
return;
}
- intel_i2c_destroy(intel_encoder->ddc_bus);
- /* Didn't find a chip, so tear down. */
- if (i2cbus != NULL)
- intel_i2c_destroy(i2cbus);
-free_intel:
drm_encoder_cleanup(&intel_encoder->base);
kfree(intel_dvo);
kfree(intel_connector);