[PATCH 06/10] drm/rcar-du/crc: Implement verify_crc_source callback

[Mahesh Kumar]

This patch implements "verify_crc_source" callback function for
rcar drm driver.

Signed-off-by: Mahesh Kumar <mahesh1.kumar at intel.com>
Cc: dri-devel at lists.freedesktop.org
---
 drivers/gpu/drm/rcar-du/rcar_du_crtc.c | 40 ++++++++++++++++++++++++++++++++++
 1 file changed, 40 insertions(+)

diff --git a/drivers/gpu/drm/rcar-du/rcar_du_crtc.c b/drivers/gpu/drm/rcar-du/rcar_du_crtc.c
index 15dc9caa128b..24eeaa7e14d7 100644
--- a/drivers/gpu/drm/rcar-du/rcar_du_crtc.c
+++ b/drivers/gpu/drm/rcar-du/rcar_du_crtc.c
@@ -756,6 +756,45 @@ static void rcar_du_crtc_disable_vblank(struct drm_crtc *crtc)
 	rcrtc->vblank_enable = false;
 }
 
+static int rcar_du_crtc_verify_crc_source(struct drm_crtc *crtc,
+					  const char *source_name,
+					  size_t *values_cnt)
+{
+	struct rcar_du_crtc *rcrtc = to_rcar_crtc(crtc);
+	unsigned int index = 0;
+	unsigned int i;
+	int ret;
+
+	/*
+	 * Parse the source name. Supported values are "plane%u" to compute the
+	 * CRC on an input plane (%u is the plane ID), and "auto" to compute the
+	 * CRC on the composer (VSP) output.
+	 */
+	if (!source_name || !strcmp(source_name, "auto")) {
+		goto out;
+	} else if (strstarts(source_name, "plane")) {
+		ret = kstrtouint(source_name + strlen("plane"), 10, &index);
+		if (ret < 0)
+			return ret;
+
+		for (i = 0; i < rcrtc->vsp->num_planes; ++i) {
+			if (index == rcrtc->vsp->planes[i].plane.base.id) {
+				index = i;
+				break;
+			}
+		}
+
+		if (i >= rcrtc->vsp->num_planes)
+			return -EINVAL;
+	} else {
+		return -EINVAL;
+	}
+
+out:
+	*values_cnt = 1;
+	return 0;
+}
+
 static int rcar_du_crtc_set_crc_source(struct drm_crtc *crtc,
 				       const char *source_name,
 				       size_t *values_cnt)
@@ -861,6 +900,7 @@ static const struct drm_crtc_funcs crtc_funcs_gen3 = {
 	.enable_vblank = rcar_du_crtc_enable_vblank,
 	.disable_vblank = rcar_du_crtc_disable_vblank,
 	.set_crc_source = rcar_du_crtc_set_crc_source,
+	.verify_crc_source = rcar_du_crtc_verify_crc_source,
 };
 
 /* -----------------------------------------------------------------------------
-- 
2.16.2