drm/gma500: add locking to fixed panel edid probing

With the recent addition of locking checks in

commit 62ff94a5492175759546f8bc61383189d6b49122
Author:     Daniel Vetter <daniel.vetter@ffwll.ch>
AuthorDate: Thu Jan 23 22:18:47 2014 +0100

    drm/crtc-helper: remove LOCKING from kerneldoc

drm_add_edid_modes started to WARN about the mode_config.mutex not
being held in the lvds and dp initialization code.

Now since this is init code locking is fairly redudant if it wouldn't
be for the drm core registering sysfs files a bit early. And the
locking WARNINGs nicely enforce that indeed all access to the mode
lists are properly protected. And a full audit shows that only i915
and gma500 touch the modes lists at init time.

Hence I've opted to wrap up this entire mode detection sequence for
fixed panels with the mode_config mutex for both lvds and edp outputs.

Cc: Patrik Jakobsson <patrik.r.jakobsson@gmail.com>
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
Acked-by: Patrik Jakobsson <patrik.r.jakobsson@gmail.com>
Signed-off-by: Dave Airlie <airlied@redhat.com>

diff --git a/drivers/gpu/drm/gma500/cdv_intel_lvds.c b/drivers/gpu/drm/gma500/cdv_intel_lvds.c
index 20e08e65d46ccfecdf06dd03c150347c14c0f327..66a41c0268340785b0b8b96f8cf7a5ed1e903959 100644 (file)
--- a/drivers/gpu/drm/gma500/cdv_intel_lvds.c
+++ b/drivers/gpu/drm/gma500/cdv_intel_lvds.c
@@ -712,6 +712,7 @@ void cdv_intel_lvds_init(struct drm_device *dev,
         * Attempt to get the fixed panel mode from DDC.  Assume that the
         * preferred mode is the right one.
         */
+       mutex_lock(&dev->mode_config.mutex);
        psb_intel_ddc_get_modes(connector,
                                &gma_encoder->ddc_bus->adapter);
        list_for_each_entry(scan, &connector->probed_modes, head) {
@@ -772,10 +773,12 @@ void cdv_intel_lvds_init(struct drm_device *dev,
        }
 
 out:
+       mutex_unlock(&dev->mode_config.mutex);
        drm_sysfs_connector_add(connector);
        return;
 
 failed_find:
+       mutex_unlock(&dev->mode_config.mutex);
        printk(KERN_ERR "Failed find\n");
        if (gma_encoder->ddc_bus)
                psb_intel_i2c_destroy(gma_encoder->ddc_bus);

diff --git a/drivers/gpu/drm/gma500/oaktrail_lvds.c b/drivers/gpu/drm/gma500/oaktrail_lvds.c
index 5e0697862736e8372c0ac5342e3d5b5b852be930..9b099468a5dbb496d0892f8c465131522aae7d9a 100644 (file)
--- a/drivers/gpu/drm/gma500/oaktrail_lvds.c
+++ b/drivers/gpu/drm/gma500/oaktrail_lvds.c
@@ -359,6 +359,7 @@ void oaktrail_lvds_init(struct drm_device *dev,
         *    if closed, act like it's not there for now
         */
 
+       mutex_lock(&dev->mode_config.mutex);
        i2c_adap = i2c_get_adapter(dev_priv->ops->i2c_bus);
        if (i2c_adap == NULL)
                dev_err(dev->dev, "No ddc adapter available!\n");
@@ -401,10 +402,14 @@ void oaktrail_lvds_init(struct drm_device *dev,
        }
 
 out:
+       mutex_unlock(&dev->mode_config.mutex);
+
        drm_sysfs_connector_add(connector);
        return;
 
 failed_find:
+       mutex_unlock(&dev->mode_config.mutex);
+
        dev_dbg(dev->dev, "No LVDS modes found, disabling.\n");
        if (gma_encoder->ddc_bus)
                psb_intel_i2c_destroy(gma_encoder->ddc_bus);

diff --git a/drivers/gpu/drm/gma500/psb_intel_lvds.c b/drivers/gpu/drm/gma500/psb_intel_lvds.c
index 32342f6990d964ddb6c798fc9159b5f5d4870b1a..891a028a0826a660c9ec7cb8b9ac4740b2777d3d 100644 (file)
--- a/drivers/gpu/drm/gma500/psb_intel_lvds.c
+++ b/drivers/gpu/drm/gma500/psb_intel_lvds.c
@@ -777,6 +777,7 @@ void psb_intel_lvds_init(struct drm_device *dev,
         * Attempt to get the fixed panel mode from DDC.  Assume that the
         * preferred mode is the right one.
         */
+       mutex_lock(&dev->mode_config.mutex);
        psb_intel_ddc_get_modes(connector, &lvds_priv->ddc_bus->adapter);
        list_for_each_entry(scan, &connector->probed_modes, head) {
                if (scan->type & DRM_MODE_TYPE_PREFERRED) {
@@ -827,10 +828,12 @@ void psb_intel_lvds_init(struct drm_device *dev,
         * actually having one.
         */
 out:
+       mutex_unlock(&dev->mode_config.mutex);
        drm_sysfs_connector_add(connector);
        return;
 
 failed_find:
+       mutex_unlock(&dev->mode_config.mutex);
        if (lvds_priv->ddc_bus)
                psb_intel_i2c_destroy(lvds_priv->ddc_bus);
 failed_ddc: