On Thu, 07 Jan 2016, Daniel Vetter daniel.vetter@ffwll.ch wrote:
On Thu, Jan 7, 2016 at 1:52 PM, Ville Syrjälä ville.syrjala@linux.intel.com wrote:
On Thu, Jan 07, 2016 at 12:44:21PM +0100, Daniel Vetter wrote:
Since
commit ac9b8236551d1177fd07b56aef9b565d1864420d Author: Ville Syrjälä ville.syrjala@linux.intel.com Date: Fri Nov 27 18:55:26 2015 +0200
drm/i915: Introduce a gmbus power domaingmbus also needs the power domain infrastructure right from the start, since as soon as we register the i2c controllers someone can use them.
v2: Adjust cleanup paths too (Chris).
Cc: Ville Syrjälä ville.syrjala@linux.intel.com Cc: Patrik Jakobsson patrik.jakobsson@linux.intel.com Cc: Imre Deak imre.deak@intel.com Cc: Jani Nikula jani.nikula@intel.com Cc: Meelis Roos mroos@linux.ee Cc: Chris Wilson chris@chris-wilson.co.uk Fixes: ac9b8236551d ("drm/i915: Introduce a gmbus power domain") Cc: stable@vger.kernel.org References: http://www.spinics.net/lists/intel-gfx/msg83075.html Tested-by: Meelis Roos mroos@linux.ee Signed-off-by: Daniel Vetter daniel.vetter@intel.com
drivers/gpu/drm/i915/i915_dma.c | 11 +++++------ 1 file changed, 5 insertions(+), 6 deletions(-)
diff --git a/drivers/gpu/drm/i915/i915_dma.c b/drivers/gpu/drm/i915/i915_dma.c index 988a3806512a..490d8b0d931e 100644 --- a/drivers/gpu/drm/i915/i915_dma.c +++ b/drivers/gpu/drm/i915/i915_dma.c @@ -398,7 +398,6 @@ static int i915_load_modeset_init(struct drm_device *dev) if (ret) goto cleanup_vga_switcheroo;
intel_power_domains_init_hw(dev_priv, false); intel_csr_ucode_init(dev_priv);@@ -1025,6 +1024,8 @@ int i915_driver_load(struct drm_device *dev, unsigned long flags)
intel_irq_init(dev_priv); intel_uncore_sanitize(dev);
intel_power_domains_init(dev_priv);intel_power_domains_init_hw(dev_priv);I think intel_init_dpio() needs to be moved too. We need to know the DPIO IOSF ports before attempting to talk to the PHY (which can happen from intel_power_domains_init_hw()).
Ugh, will change.
I'm also wondering why we're doing gmbus init this early. We shouldn't need it until modeset init.
Anyone can access the gmbus controller once we register it. Userspace can (like what seems to happen on Meelis' box), but also the i2c core has some auto-probed stuff in some configs afaik.
Ville's question was why we register the i2c adapters this early.
As I explained in [1], the auto-probing happens when there's an i2c driver with matching class (I2C_CLASS_DDC). That's what happens on Meelis' box. But yes, we need to take userspace into account as well.
In short, when we call intel_gmbus_setup(), we need to be ready for i2c communication.
BR, Jani.
[1] http://mid.gmane.org/87vb75znpz.fsf@intel.com