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| author | Jani Nikula <jani.nikula@intel.com> | 2012-08-13 14:22:35 +0400 |
|---|---|---|
| committer | Daniel Vetter <daniel.vetter@ffwll.ch> | 2012-08-17 11:21:36 +0400 |
| commit | f1a2f5b7c5f0941d23eef0a095c0b99bf8d051e6 (patch) | |
| tree | 6826689fea622320d9ee48e01bbd8f1b0fe13c2b /drivers/gpu/drm/i915 | |
| parent | 4eab81366465aedcfd26de960c595bc03599c09f (diff) | |
| download | linux-f1a2f5b7c5f0941d23eef0a095c0b99bf8d051e6.tar.xz | |
drm/i915: fall back to bit-banging if GMBUS fails in CRT EDID reads
GMBUS was enabled over bit-banging as the default in commits:
commit c3dfefa0a6d235bd465309e12f4c56ea16e71111
Author: Daniel Vetter <daniel.vetter@ffwll.ch>
Date: Tue Feb 14 22:37:25 2012 +0100
drm/i915: reenable gmbus on gen3+ again
and
commit 0fb3f969c8683505fb7323c06bf8a999a5a45a15
Author: Daniel Vetter <daniel.vetter@ffwll.ch>
Date: Fri Mar 2 19:38:30 2012 +0100
drm/i915: enable gmbus on gen2
Unfortunately, GMBUS seems to fail on some CRT displays. Add a bit-banging
fallback to CRT EDID reads.
LKML-Reference: <201207251020.47637.maciej.rutecki@gmail.com>
Bugzilla: https://bugzilla.kernel.org/show_bug.cgi?id=45881
Signed-off-by: Jani Nikula <jani.nikula@intel.com>
Tested-by: Alex Ferrando <alferpal@gmail.com>
Cc: stable@vger.kernel.org (for 3.4+3.5)
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
Diffstat (limited to 'drivers/gpu/drm/i915')
| -rw-r--r-- | drivers/gpu/drm/i915/intel_crt.c | 36 |
1 files changed, 33 insertions, 3 deletions
diff --git a/drivers/gpu/drm/i915/intel_crt.c b/drivers/gpu/drm/i915/intel_crt.c index 7ed4a41c3965..23bdc8cd1458 100644 --- a/drivers/gpu/drm/i915/intel_crt.c +++ b/drivers/gpu/drm/i915/intel_crt.c @@ -326,6 +326,36 @@ static bool intel_crt_detect_hotplug(struct drm_connector *connector) return ret; } +static struct edid *intel_crt_get_edid(struct drm_connector *connector, + struct i2c_adapter *i2c) +{ + struct edid *edid; + + edid = drm_get_edid(connector, i2c); + + if (!edid && !intel_gmbus_is_forced_bit(i2c)) { + DRM_DEBUG_KMS("CRT GMBUS EDID read failed, retry using GPIO bit-banging\n"); + intel_gmbus_force_bit(i2c, true); + edid = drm_get_edid(connector, i2c); + intel_gmbus_force_bit(i2c, false); + } + + return edid; +} + +/* local version of intel_ddc_get_modes() to use intel_crt_get_edid() */ +static int intel_crt_ddc_get_modes(struct drm_connector *connector, + struct i2c_adapter *adapter) +{ + struct edid *edid; + + edid = intel_crt_get_edid(connector, adapter); + if (!edid) + return 0; + + return intel_connector_update_modes(connector, edid); +} + static bool intel_crt_detect_ddc(struct drm_connector *connector) { struct intel_crt *crt = intel_attached_crt(connector); @@ -336,7 +366,7 @@ static bool intel_crt_detect_ddc(struct drm_connector *connector) BUG_ON(crt->base.type != INTEL_OUTPUT_ANALOG); i2c = intel_gmbus_get_adapter(dev_priv, dev_priv->crt_ddc_pin); - edid = drm_get_edid(connector, i2c); + edid = intel_crt_get_edid(connector, i2c); if (edid) { bool is_digital = edid->input & DRM_EDID_INPUT_DIGITAL; @@ -544,13 +574,13 @@ static int intel_crt_get_modes(struct drm_connector *connector) struct i2c_adapter *i2c; i2c = intel_gmbus_get_adapter(dev_priv, dev_priv->crt_ddc_pin); - ret = intel_ddc_get_modes(connector, i2c); + ret = intel_crt_ddc_get_modes(connector, i2c); if (ret || !IS_G4X(dev)) return ret; /* Try to probe digital port for output in DVI-I -> VGA mode. */ i2c = intel_gmbus_get_adapter(dev_priv, GMBUS_PORT_DPB); - return intel_ddc_get_modes(connector, i2c); + return intel_crt_ddc_get_modes(connector, i2c); } static int intel_crt_set_property(struct drm_connector *connector, |