media: pisp_be: Remove config validation from schedule()

The config parameters buffer is already validated in
pisp_be_validate_config() at .buf_prepare() time.

However some of the same validations are also performed at
pispbe_schedule() time. In particular the function checks that:

1) config.num_tiles is valid
2) At least one of the BAYER or RGB input is enabled

The input config validation is already performed in
pisp_be_validate_config() and while job.hw_enables is modified by
pispbe_xlate_addrs(), the function only resets the input masks if

- there is no input buffer available, but pispbe_prepare_job() fails
  before calling pispbe_xlate_addrs() in this case
- bayer_enable is 0, but in this case rgb_enable is valid as guaranteed
  by pisp_be_validate_config()
- only outputs are reset in rgb_enable

For this reasons there is no need to repeat the check at
pispbe_schedule() time.

The num_tiles validation can be moved to pisp_be_validate_config() as
well. As num_tiles is a u32 it can'be be < 0, so change the sanity
check accordingly.

Reviewed-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com>
Reviewed-by: Naushir Patuck <naush@raspberrypi.com>
Signed-off-by: Jacopo Mondi <jacopo.mondi@ideasonboard.com>

Author: Jacopo Mondi

drivers/media/platform/raspberrypi/pisp_be/pisp_be.c

@@ -621,25 +621,6 @@ static void pispbe_schedule(struct pispbe_dev *pispbe,
 		pispbe->hw_busy = true;
 		spin_unlock_irqrestore(&pispbe->hw_lock, flags);
 
-		if (job.config->num_tiles <= 0 ||
-		    job.config->num_tiles > PISP_BACK_END_NUM_TILES ||
-		    !((job.hw_enables.bayer_enables |
-		       job.hw_enables.rgb_enables) &
-		      PISP_BE_BAYER_ENABLE_INPUT)) {
-			/*
-			 * Bad job. We can't let it proceed as it could lock up
-			 * the hardware, or worse!
-			 *
-			 * For now, just force num_tiles to 0, which causes the
-			 * H/W to do something bizarre but survivable. It
-			 * increments (started,done) counters by more than 1,
-			 * but we seem to survive...
-			 */
-			dev_dbg(pispbe->dev, "Bad job: invalid number of tiles: %u\n",
-				job.config->num_tiles);
-			job.config->num_tiles = 0;
-		}
-
 		pispbe_queue_job(pispbe, &job);
 
 		return;
@@ -738,6 +719,13 @@ static int pisp_be_validate_config(struct pispbe_node_group *node_group,
 		return -EIO;
 	}
 
+	if (config->num_tiles == 0 ||
+	    config->num_tiles > PISP_BACK_END_NUM_TILES) {
+		dev_dbg(dev, "%s: Invalid number of tiles: %d\n", __func__,
+			config->num_tiles);
+		return -EINVAL;
+	}
+
 	/* Ensure output config strides and buffer sizes match the V4L2 formats. */
 	fmt = &node_group->node[TDN_OUTPUT_NODE].format;
 	if (bayer_enables & PISP_BE_BAYER_ENABLE_TDN_OUTPUT) {