From 46509475a817ed099829be2a8d03cdbc355a284e Mon Sep 17 00:00:00 2001 From: =?utf8?q?Ville=20Syrj=C3=A4l=C3=A4?= Date: Tue, 31 Mar 2015 10:37:21 +0300 Subject: [PATCH] drm/i915: Enable DVO 2x clock around DVO encoder init MIME-Version: 1.0 Content-Type: text/plain; charset=utf8 Content-Transfer-Encoding: 8bit ns2501 requires the DVO 2x clock before it will respond to i2c access, so make sure the clock is enabled when we try to initialize the encoder. Fixes the display getting lost on module reload on my Fujitsu/Siemens Lifebook S6010. Signed-off-by: Ville Syrjälä Signed-off-by: Daniel Vetter --- drivers/gpu/drm/i915/intel_dvo.c | 17 +++++++++++++++++ 1 file changed, 17 insertions(+) diff --git a/drivers/gpu/drm/i915/intel_dvo.c b/drivers/gpu/drm/i915/intel_dvo.c index 4ccd6c3..f2ed122 100644 --- a/drivers/gpu/drm/i915/intel_dvo.c +++ b/drivers/gpu/drm/i915/intel_dvo.c @@ -495,6 +495,8 @@ void intel_dvo_init(struct drm_device *dev) struct i2c_adapter *i2c; int gpio; bool dvoinit; + enum pipe pipe; + uint32_t dpll[2]; /* Allow the I2C driver info to specify the GPIO to be used in * special cases, but otherwise default to what's defined @@ -520,8 +522,23 @@ void intel_dvo_init(struct drm_device *dev) */ intel_gmbus_force_bit(i2c, true); + /* ns2501 requires the DVO 2x clock before it will + * respond to i2c accesses, so make sure we have + * have the clock enabled before we attempt to + * initialize the device. + */ + for_each_pipe(dev_priv, pipe) { + dpll[pipe] = I915_READ(DPLL(pipe)); + I915_WRITE(DPLL(pipe), dpll[pipe] | DPLL_DVO_2X_MODE); + } + dvoinit = dvo->dev_ops->init(&intel_dvo->dev, i2c); + /* restore the DVO 2x clock state to original */ + for_each_pipe(dev_priv, pipe) { + I915_WRITE(DPLL(pipe), dpll[pipe]); + } + intel_gmbus_force_bit(i2c, false); if (!dvoinit) -- 2.7.4