drm/irq: track the irq installed in drm_irq_install in dev->irq

To get rid of the dev->bus->get_irq callback we need to pass in the
desired irq explicitly into drm_irq_install. To avoid having to do the
same for drm_irq_unistall just track it internally. That leaves
drivers with less room to botch things up.

v2: Add the hunk lost in an earlier patch to this one (Thierry).

v3: Fix up the totally fumbled logic in drm_irq_install and use the
local variable consistently. Spotted by both Thierry and Laurent.
Shame on me for failing to properly test the rebase version of this
patch ...

Cc: Thierry Reding <thierry.reding@gmail.com>
Cc: Laurent Pinchart <laurent.pinchart@ideasonboard.com>
Reviewed-by: Thierry Reding <treding@nvidia.com>
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>

drivers/gpu/drm/drm_irq.c

@@ -249,14 +249,16 @@ static inline int drm_dev_to_irq(struct drm_device *dev)
  */
 int drm_irq_install(struct drm_device *dev)
 {
-	int ret;
+	int ret, irq;
 	unsigned long sh_flags = 0;
 	char *irqname;
 
+	irq = drm_dev_to_irq(dev);
+
 	if (!drm_core_check_feature(dev, DRIVER_HAVE_IRQ))
 		return -EINVAL;
 
-	if (drm_dev_to_irq(dev) == 0)
+	if (irq == 0)
 		return -EINVAL;
 
 	/* Driver must have been initialized */
@@ -267,7 +269,7 @@ int drm_irq_install(struct drm_device *dev)
 		return -EBUSY;
 	dev->irq_enabled = true;
 
-	DRM_DEBUG("irq=%d\n", drm_dev_to_irq(dev));
+	DRM_DEBUG("irq=%d\n", irq);
 
 	/* Before installing handler */
 	if (dev->driver->irq_preinstall)
@@ -282,7 +284,7 @@ int drm_irq_install(struct drm_device *dev)
 	else
 		irqname = dev->driver->name;
 
-	ret = request_irq(drm_dev_to_irq(dev), dev->driver->irq_handler,
+	ret = request_irq(irq, dev->driver->irq_handler,
 			  sh_flags, irqname, dev);
 
 	if (ret < 0) {
@@ -301,7 +303,9 @@ int drm_irq_install(struct drm_device *dev)
 		dev->irq_enabled = false;
 		if (!drm_core_check_feature(dev, DRIVER_MODESET))
 			vga_client_register(dev->pdev, NULL, NULL, NULL);
-		free_irq(drm_dev_to_irq(dev), dev);
+		free_irq(irq, dev);
+	} else {
+		dev->irq = irq;
 	}
 
 	return ret;
@@ -344,15 +348,15 @@ int drm_irq_uninstall(struct drm_device *dev)
 	if (!irq_enabled)
 		return -EINVAL;
 
-	DRM_DEBUG("irq=%d\n", drm_dev_to_irq(dev));
+	DRM_DEBUG("irq=%d\n", dev->irq);
 
 	if (!drm_core_check_feature(dev, DRIVER_MODESET))
 		vga_client_register(dev->pdev, NULL, NULL, NULL);
 
 	if (dev->driver->irq_uninstall)
 		dev->driver->irq_uninstall(dev);
 
-	free_irq(drm_dev_to_irq(dev), dev);
+	free_irq(dev->irq, dev);
 
 	return 0;
 }

include/drm/drmP.h

@@ -1107,6 +1107,8 @@ struct drm_device {
 	/** \name Context support */
 	/*@{ */
 	bool irq_enabled;		/**< True if irq handler is enabled */
+	int irq;
+
 	__volatile__ long context_flag;	/**< Context swapping flag */
 	int last_context;		/**< Last current context */
 	/*@} */