[PATCH 05/11] drm/i915: get runtime PM while trying to detect CRT

Paulo Zanoni
2014-02-21T16:53:00Z

From: Paulo Zanoni <paulo.r.zanoni@intel.com>

Otherwise we'll read registers that return 0xffffffff, trigger some
WARNs, think CRT is actually connected (because certain bits are 1),
and fail the drm-resources-equal testcase!

Tested on a SNB machine with runtime PM support (which is not upstream
yet, but is already on my public tree at freedesktop.org, and will
hopefully eventually become upstream).

Testcase: igt/pm_pc8/drm-resources-equal
Signed-off-by: Paulo Zanoni <paulo.r.zanoni@intel.com>
---
drivers/gpu/drm/i915/intel_crt.c | 26 +++++++++++++++++++-------
1 file changed, 19 insertions(+), 7 deletions(-)

diff --git a/drivers/gpu/drm/i915/intel_crt.c b/drivers/gpu/drm/i915/intel_crt.c
index 9864aa1..4c1230c 100644
--- a/drivers/gpu/drm/i915/intel_crt.c
+++ b/drivers/gpu/drm/i915/intel_crt.c
@@ -630,10 +630,13 @@ static enum drm_connector_status
intel_crt_detect(struct drm_connector *connector, bool force)
{
struct drm_device *dev = connector->dev;
+ struct drm_i915_private *dev_priv = dev->dev_private;
struct intel_crt *crt = intel_attached_crt(connector);
enum drm_connector_status status;
struct intel_load_detect_pipe tmp;

+ intel_runtime_pm_get(dev_priv);
+
DRM_DEBUG_KMS("[CONNECTOR:%d:%s] force=%d\n",
connector->base.id, drm_get_connector_name(connector),
force);
@@ -645,23 +648,30 @@ intel_crt_detect(struct drm_connector *connector, bool force)
*/
if (intel_crt_detect_hotplug(connector)) {
DRM_DEBUG_KMS("CRT detected via hotplug\n");
- return connector_status_connected;
+ status = connector_status_connected;
+ goto out;
} else
DRM_DEBUG_KMS("CRT not detected via hotplug\n");
}

- if (intel_crt_detect_ddc(connector))
- return connector_status_connected;
+ if (intel_crt_detect_ddc(connector)) {
+ status = connector_status_connected;
+ goto out;
+ }

/* Load detection is broken on HPD capable machines. Whoever wants a
* broken monitor (without edid) to work behind a broken kvm (that fails
* to have the right resistors for HP detection) needs to fix this up.
* For now just bail out. */
- if (I915_HAS_HOTPLUG(dev))
- return connector_status_disconnected;
+ if (I915_HAS_HOTPLUG(dev)) {
+ status = connector_status_disconnected;
+ goto out;
+ }

- if (!force)
- return connector->status;
+ if (!force) {
+ status = connector->status;
+ goto out;
+ }

/* for pre-945g platforms use load detect */
if (intel_get_load_detect_pipe(connector, NULL, &tmp)) {
@@ -673,6 +683,8 @@ intel_crt_detect(struct drm_connector *connector, bool force)
} else
status = connector_status_unknown;

+out:
+ intel_runtime_pm_put(dev_priv);
return status;
}

--
1.8.5.3