drm/kmb: Convert to Linux IRQ interfaces

Drop the DRM IRQ midlayer in favor of Linux IRQ interfaces. DRM's
IRQ helpers are mostly useful for UMS drivers. Modern KMS drivers
don't benefit from using it.

DRM IRQ callbacks are now being called directly or inlined.
Signed-off-by: Thomas Zimmermann <tzimmermann@suse.de>
Acked-by: Sam Ravnborg <sam@ravnborg.org>
Tested-by: Anitha Chrisanthus <anitha.chrisanthus@intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20210803090704.32152-7-tzimmermann@suse.de

drivers/gpu/drm/kmb/kmb_drv.c

@@ -17,7 +17,6 @@
 #include <drm/drm_drv.h>
 #include <drm/drm_gem_cma_helper.h>
 #include <drm/drm_gem_framebuffer_helper.h>
-#include <drm/drm_irq.h>
 #include <drm/drm_probe_helper.h>
 #include <drm/drm_vblank.h>
 
@@ -399,14 +398,29 @@ static void kmb_irq_reset(struct drm_device *drm)
 	kmb_write_lcd(to_kmb(drm), LCD_INT_ENABLE, 0);
 }
 
+static int kmb_irq_install(struct drm_device *drm, unsigned int irq)
+{
+	if (irq == IRQ_NOTCONNECTED)
+		return -ENOTCONN;
+
+	kmb_irq_reset(drm);
+
+	return request_irq(irq, kmb_isr, 0, drm->driver->name, drm);
+}
+
+static void kmb_irq_uninstall(struct drm_device *drm)
+{
+	struct kmb_drm_private *kmb = to_kmb(drm);
+
+	kmb_irq_reset(drm);
+	free_irq(kmb->irq_lcd, drm);
+}
+
 DEFINE_DRM_GEM_CMA_FOPS(fops);
 
 static const struct drm_driver kmb_driver = {
 	.driver_features = DRIVER_GEM |
 	    DRIVER_MODESET | DRIVER_ATOMIC,
-	.irq_handler = kmb_isr,
-	.irq_preinstall = kmb_irq_reset,
-	.irq_uninstall = kmb_irq_reset,
 	/* GEM Operations */
 	.fops = &fops,
 	DRM_GEM_CMA_DRIVER_OPS_VMAP,
@@ -428,7 +442,7 @@ static int kmb_remove(struct platform_device *pdev)
 	of_node_put(kmb->crtc.port);
 	kmb->crtc.port = NULL;
 	pm_runtime_get_sync(drm->dev);
-	drm_irq_uninstall(drm);
+	kmb_irq_uninstall(drm);
 	pm_runtime_put_sync(drm->dev);
 	pm_runtime_disable(drm->dev);
 
@@ -518,7 +532,7 @@ static int kmb_probe(struct platform_device *pdev)
 	if (ret)
 		goto err_free;
 
-	ret = drm_irq_install(&kmb->drm, kmb->irq_lcd);
+	ret = kmb_irq_install(&kmb->drm, kmb->irq_lcd);
 	if (ret < 0) {
 		drm_err(&kmb->drm, "failed to install IRQ handler\n");
 		goto err_irq;