gma500: tidying up the power stuff a spot

In particular don't destroy static mutexes, it upsets things

Signed-off-by: Alan Cox <alan@linux.intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>

diff --git a/drivers/staging/gma500/power.c b/drivers/staging/gma500/power.c
index fc2324e..0eee7fb 100644 (file)
--- a/drivers/staging/gma500/power.c
+++ b/drivers/staging/gma500/power.c
@@ -27,6 +27,7 @@
  * Massively reworked
  *    Alan Cox <alan@linux.intel.com>
  */
+
 #include "psb_powermgmt.h"
 #include "psb_drv.h"
 #include "psb_reg.h"
@@ -34,7 +35,8 @@
 #include <linux/mutex.h>
 #include <linux/pm_runtime.h>
 
-static struct mutex power_mutex;
+static struct mutex power_mutex;       /* Serialize power ops */
+static struct mutex power_ctrl_mutex;  /* Serialize power claim */
 
 /**
  *     gma_power_init          -       initialise power manager
@@ -46,8 +48,7 @@ void gma_power_init(struct drm_device *dev)
 {
        struct drm_psb_private *dev_priv = dev->dev_private;
 
-       /* FIXME: need to sort out fetching apm_reg for both platforms ?? */
-
+       /* FIXME: Move APM/OSPM base into relevant device code */
        dev_priv->apm_base = dev_priv->apm_reg & 0xffff;
        dev_priv->ospm_base &= 0xffff;
 
@@ -55,6 +56,7 @@ void gma_power_init(struct drm_device *dev)
        dev_priv->display_count = 0;    /* Currently no users */
        dev_priv->suspended = false;    /* And not suspended */
        mutex_init(&power_mutex);
+       mutex_init(&power_ctrl_mutex);
 
        dev_priv->ops->init_pm(dev);
 }
@@ -67,23 +69,15 @@ void gma_power_init(struct drm_device *dev)
  */
 void gma_power_uninit(struct drm_device *dev)
 {
-       mutex_destroy(&power_mutex);
        pm_runtime_disable(&dev->pdev->dev);
        pm_runtime_set_suspended(&dev->pdev->dev);
 }
 
-
-
-
 /**
  *     gma_suspend_display     -       suspend the display logic
  *     @dev: our DRM device
  *
  *     Suspend the display logic of the graphics interface
- *
- *     FIXME: This ought to be replaced by a dev_priv-> ops interface
- *     where the various platforms register their save/restore methods
- *     and keep them in their own support files.
  */
 static void gma_suspend_display(struct drm_device *dev)
 {
@@ -210,7 +204,6 @@ int gma_power_suspend(struct pci_dev *pdev, pm_message_t state)
        return 0;
 }
 
-
 /**
  *     gma_power_resume                -       resume power
  *     @pdev: PCI device
@@ -230,8 +223,6 @@ int gma_power_resume(struct pci_dev *pdev)
        return 0;
 }
 
-
-
 /**
  *     gma_power_is_on         -       returne true if power is on
  *     @dev: our DRM device
@@ -244,7 +235,6 @@ bool gma_power_is_on(struct drm_device *dev)
        return dev_priv->display_power;
 }
 
-
 /**
  *     gma_power_begin         -       begin requiring power
  *     @dev: our DRM device
@@ -252,22 +242,22 @@ bool gma_power_is_on(struct drm_device *dev)
  *
  *     Begin an action that requires the display power island is enabled.
  *     We refcount the islands.
- *
- *     FIXME: locking
  */
 bool gma_power_begin(struct drm_device *dev, bool force_on)
 {
        struct drm_psb_private *dev_priv = dev->dev_private;
        int ret;
 
+       mutex_lock(&power_ctrl_mutex);
        /* Power already on ? */
        if (dev_priv->display_power) {
                dev_priv->display_count++;
                pm_runtime_get(&dev->pdev->dev);
+               mutex_unlock(&power_ctrl_mutex);
                return true;
        }
        if (force_on == false)
-               return false;
+               goto out_false;
 
        /* Ok power up needed */
        ret = gma_resume_pci(dev->pdev);
@@ -276,12 +266,14 @@ bool gma_power_begin(struct drm_device *dev, bool force_on)
                psb_irq_postinstall(dev);
                pm_runtime_get(&dev->pdev->dev);
                dev_priv->display_count++;
+               mutex_unlock(&power_ctrl_mutex);
                return true;
        }
+out_false:
+       mutex_unlock(&power_ctrl_mutex);
        return false;
 }
 
-
 /**
  *     gma_power_end           -       end use of power
  *     @dev: Our DRM device
@@ -292,8 +284,10 @@ bool gma_power_begin(struct drm_device *dev, bool force_on)
 void gma_power_end(struct drm_device *dev)
 {
        struct drm_psb_private *dev_priv = dev->dev_private;
+       mutex_lock(&power_ctrl_mutex);
        dev_priv->display_count--;
        WARN_ON(dev_priv->display_count < 0);
+       mutex_unlock(&power_ctrl_mutex);
        pm_runtime_put(&dev->pdev->dev);
 }
 
@@ -317,4 +311,3 @@ int psb_runtime_idle(struct device *dev)
        else
                return 1;
 }
-