drm/gm12u320: More drmm_

The drm_mode_config_cleanup call we can drop, and all the allocations
we can switch over to drmm_kzalloc. Unfortunately the work queue is
still present, so can't get rid of the drm_driver->release function
outright.

v2: Use drmm_mode_config_init() for more clarity (Sam, Thomas)

Cc: Sam Ravnborg <sam@ravnborg.org>
Cc: Thomas Zimmermann <tzimmermann@suse.de>
Reviewed-by: Hans de Goede <hdegoede@redhat.com> (v1)
Signed-off-by: Daniel Vetter <daniel.vetter@intel.com>
Cc: Hans de Goede <hdegoede@redhat.com>
Cc: "Noralf Trønnes" <noralf@tronnes.org>
Link: https://patchwork.freedesktop.org/patch/msgid/20200323144950.3018436-43-daniel.vetter@ffwll.ch

drivers/gpu/drm/tiny/gm12u320.c

@@ -160,7 +160,7 @@ static int gm12u320_usb_alloc(struct gm12u320_device *gm12u320)
 	int i, block_size;
 	const char *hdr;
 
-	gm12u320->cmd_buf = kmalloc(CMD_SIZE, GFP_KERNEL);
+	gm12u320->cmd_buf = drmm_kmalloc(&gm12u320->dev, CMD_SIZE, GFP_KERNEL);
 	if (!gm12u320->cmd_buf)
 		return -ENOMEM;
 
@@ -173,7 +173,8 @@ static int gm12u320_usb_alloc(struct gm12u320_device *gm12u320)
 			hdr = data_block_header;
 		}
 
-		gm12u320->data_buf[i] = kzalloc(block_size, GFP_KERNEL);
+		gm12u320->data_buf[i] = drmm_kzalloc(&gm12u320->dev,
+						     block_size, GFP_KERNEL);
 		if (!gm12u320->data_buf[i])
 			return -ENOMEM;
 
@@ -192,15 +193,8 @@ static int gm12u320_usb_alloc(struct gm12u320_device *gm12u320)
 
 static void gm12u320_usb_free(struct gm12u320_device *gm12u320)
 {
-	int i;
-
 	if (gm12u320->fb_update.workq)
 		destroy_workqueue(gm12u320->fb_update.workq);
-
-	for (i = 0; i < GM12U320_BLOCK_COUNT; i++)
-		kfree(gm12u320->data_buf[i]);
-
-	kfree(gm12u320->cmd_buf);
 }
 
 static int gm12u320_misc_request(struct gm12u320_device *gm12u320,
@@ -636,7 +630,6 @@ static void gm12u320_driver_release(struct drm_device *dev)
 	struct gm12u320_device *gm12u320 = dev->dev_private;
 
 	gm12u320_usb_free(gm12u320);
-	drm_mode_config_cleanup(dev);
 }
 
 DEFINE_DRM_GEM_FOPS(gm12u320_fops);
@@ -693,7 +686,10 @@ static int gm12u320_usb_probe(struct usb_interface *interface,
 	dev->dev_private = gm12u320;
 	drmm_add_final_kfree(dev, gm12u320);
 
-	drm_mode_config_init(dev);
+	ret = drmm_mode_config_init(dev);
+	if (ret)
+		goto err_put;
+
 	dev->mode_config.min_width = GM12U320_USER_WIDTH;
 	dev->mode_config.max_width = GM12U320_USER_WIDTH;
 	dev->mode_config.min_height = GM12U320_HEIGHT;