drm: kill DRIVER_REQUIRE_AGP

Only the two intel drivers need this and they can easily check for
working agp support in their driver ->load callbacks.

This is the only reason why agp initialization could fail, so allows
us to rip out a bit of error handling code in the next patch.

Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
Signed-off-by: Dave Airlie <airlied@redhat.com>

drivers/gpu/drm/drm_pci.c

@@ -267,11 +267,6 @@ static int drm_pci_agp_init(struct drm_device *dev)
 	if (drm_core_has_AGP(dev)) {
 		if (drm_pci_device_is_agp(dev))
 			dev->agp = drm_agp_init(dev);
-		if (drm_core_check_feature(dev, DRIVER_REQUIRE_AGP)
-		    && (dev->agp == NULL)) {
-			DRM_ERROR("Cannot initialize the agpgart module.\n");
-			return -EINVAL;
-		}
 		if (dev->agp) {
 			dev->agp->agp_mtrr = arch_phys_wc_add(
 				dev->agp->agp_info.aper_base,

drivers/gpu/drm/i810/i810_dma.c

@@ -1193,6 +1193,10 @@ static int i810_flip_bufs(struct drm_device *dev, void *data,
 
 int i810_driver_load(struct drm_device *dev, unsigned long flags)
 {
+	/* Our userspace depends upon the agp mapping support. */
+	if (!dev->agp)
+		return -EINVAL;
+
 	pci_set_master(dev->pdev);
 
 	return 0;

drivers/gpu/drm/i810/i810_drv.c

@@ -57,7 +57,7 @@ static const struct file_operations i810_driver_fops = {
 
 static struct drm_driver driver = {
 	.driver_features =
-	    DRIVER_USE_AGP | DRIVER_REQUIRE_AGP |
+	    DRIVER_USE_AGP |
 	    DRIVER_HAVE_DMA,
 	.dev_priv_size = sizeof(drm_i810_buf_priv_t),
 	.load = i810_driver_load,

drivers/gpu/drm/i915/i915_dma.c

@@ -1476,6 +1476,10 @@ int i915_driver_load(struct drm_device *dev, unsigned long flags)
 		return -ENODEV;
 	}
 
+	/* UMS needs agp support. */
+	if (!drm_core_check_feature(dev, DRIVER_MODESET) && !dev->agp)
+		return -EINVAL;
+
 	dev_priv = kzalloc(sizeof(*dev_priv), GFP_KERNEL);
 	if (dev_priv == NULL)
 		return -ENOMEM;

drivers/gpu/drm/i915/i915_drv.c

@@ -828,7 +828,7 @@ static int i915_pci_probe(struct pci_dev *pdev, const struct pci_device_id *ent)
 	if (PCI_FUNC(pdev->devfn))
 		return -ENODEV;
 
-	driver.driver_features &= ~(DRIVER_USE_AGP | DRIVER_REQUIRE_AGP);
+	driver.driver_features &= ~(DRIVER_USE_AGP);
 
 	return drm_get_pci_dev(pdev, ent, &driver);
 }
@@ -936,7 +936,7 @@ static struct drm_driver driver = {
 	 * deal with them for Intel hardware.
 	 */
 	.driver_features =
-	    DRIVER_USE_AGP | DRIVER_REQUIRE_AGP |
+	    DRIVER_USE_AGP |
 	    DRIVER_HAVE_IRQ | DRIVER_IRQ_SHARED | DRIVER_GEM | DRIVER_PRIME |
 	    DRIVER_RENDER,
 	.load = i915_driver_load,

include/drm/drmP.h

@@ -137,7 +137,6 @@ int drm_err(const char *func, const char *format, ...);
 
 /* driver capabilities and requirements mask */
 #define DRIVER_USE_AGP     0x1
-#define DRIVER_REQUIRE_AGP 0x2
 #define DRIVER_PCI_DMA     0x8
 #define DRIVER_SG          0x10
 #define DRIVER_HAVE_DMA    0x20