[PATCH 3/8] drm: Add drm_for_each_connector_encoder_ids()

[Ville Syrjala]

From: Ville Syrjälä <ville.syrjala at linux.intel.com>

Add a convenience macro for iterating connector->encoder_ids[].
Isolates the users from the implementation details.

Also use ARRAY_SIZE() when populating the array to avoid spreading
knowledge about the array size all over.

Signed-off-by: Ville Syrjälä <ville.syrjala at linux.intel.com>
---
 drivers/gpu/drm/drm_connector.c    | 22 ++++++++++------------
 drivers/gpu/drm/drm_fb_helper.c    |  6 +++---
 drivers/gpu/drm/drm_probe_helper.c |  9 +++++----
 include/drm/drm_connector.h        | 11 +++++++++++
 4 files changed, 29 insertions(+), 19 deletions(-)

diff --git a/drivers/gpu/drm/drm_connector.c b/drivers/gpu/drm/drm_connector.c
index 2f9ebddd178e..c43646cb8145 100644
--- a/drivers/gpu/drm/drm_connector.c
+++ b/drivers/gpu/drm/drm_connector.c
@@ -321,7 +321,7 @@ int drm_mode_connector_attach_encoder(struct drm_connector *connector,
 	if (WARN_ON(connector->encoder))
 		return -EINVAL;
 
-	for (i = 0; i < DRM_CONNECTOR_MAX_ENCODER; i++) {
+	for (i = 0; i < ARRAY_SIZE(connector->encoder_ids); i++) {
 		if (connector->encoder_ids[i] == 0) {
 			connector->encoder_ids[i] = encoder->base.id;
 			return 0;
@@ -1693,6 +1693,7 @@ int drm_mode_getconnector(struct drm_device *dev, void *data,
 	int encoders_count = 0;
 	int ret = 0;
 	int copied = 0;
+	u32 encoder_id;
 	int i;
 	struct drm_mode_modeinfo u_mode;
 	struct drm_mode_modeinfo __user *mode_ptr;
@@ -1708,22 +1709,19 @@ int drm_mode_getconnector(struct drm_device *dev, void *data,
 	if (!connector)
 		return -ENOENT;
 
-	for (i = 0; i < DRM_CONNECTOR_MAX_ENCODER; i++)
-		if (connector->encoder_ids[i] != 0)
-			encoders_count++;
+	drm_for_each_connector_encoder_ids(connector, encoder_id, i)
+		encoders_count++;
 
 	if ((out_resp->count_encoders >= encoders_count) && encoders_count) {
 		copied = 0;
 		encoder_ptr = (uint32_t __user *)(unsigned long)(out_resp->encoders_ptr);
-		for (i = 0; i < DRM_CONNECTOR_MAX_ENCODER; i++) {
-			if (connector->encoder_ids[i] != 0) {
-				if (put_user(connector->encoder_ids[i],
-					     encoder_ptr + copied)) {
-					ret = -EFAULT;
-					goto out;
-				}
-				copied++;
+
+		drm_for_each_connector_encoder_ids(connector, encoder_id, i) {
+			if (put_user(encoder_id, encoder_ptr + copied)) {
+				ret = -EFAULT;
+				goto out;
 			}
+			copied++;
 		}
 	}
 	out_resp->count_encoders = encoders_count;
diff --git a/drivers/gpu/drm/drm_fb_helper.c b/drivers/gpu/drm/drm_fb_helper.c
index 61c39cd75a27..e086b08748f4 100644
--- a/drivers/gpu/drm/drm_fb_helper.c
+++ b/drivers/gpu/drm/drm_fb_helper.c
@@ -2326,12 +2326,12 @@ static bool drm_target_preferred(struct drm_fb_helper *fb_helper,
 static bool connector_crtc_ok(struct drm_connector *connector,
 			      struct drm_crtc *crtc)
 {
+	u32 encoder_id;
 	int i;
 
-	for (i = 0; i < DRM_CONNECTOR_MAX_ENCODER; i++) {
+	drm_for_each_connector_encoder_ids(connector, encoder_id, i) {
 		struct drm_encoder *encoder =
-			drm_encoder_find(connector->dev, NULL,
-					 connector->encoder_ids[i]);
+			drm_encoder_find(connector->dev, NULL, encoder_id);
 
 		if (encoder->possible_crtcs & drm_crtc_mask(crtc))
 			return true;
diff --git a/drivers/gpu/drm/drm_probe_helper.c b/drivers/gpu/drm/drm_probe_helper.c
index 527743394150..0239f76c52fb 100644
--- a/drivers/gpu/drm/drm_probe_helper.c
+++ b/drivers/gpu/drm/drm_probe_helper.c
@@ -88,9 +88,9 @@ drm_mode_validate_pipeline(struct drm_display_mode *mode,
 			    struct drm_connector *connector)
 {
 	struct drm_device *dev = connector->dev;
-	uint32_t *ids = connector->encoder_ids;
 	enum drm_mode_status ret = MODE_OK;
-	unsigned int i;
+	u32 encoder_id;
+	int i;
 
 	/* Step 1: Validate against connector */
 	ret = drm_connector_mode_valid(connector, mode);
@@ -98,8 +98,9 @@ drm_mode_validate_pipeline(struct drm_display_mode *mode,
 		return ret;
 
 	/* Step 2: Validate against encoders and crtcs */
-	for (i = 0; i < DRM_CONNECTOR_MAX_ENCODER; i++) {
-		struct drm_encoder *encoder = drm_encoder_find(dev, NULL, ids[i]);
+	drm_for_each_connector_encoder_ids(connector, encoder_id, i) {
+		struct drm_encoder *encoder =
+			drm_encoder_find(dev, NULL, encoder_id);
 		struct drm_crtc *crtc;
 
 		if (!encoder)
diff --git a/include/drm/drm_connector.h b/include/drm/drm_connector.h
index 14ab58ade87f..4a0363f7dd8c 100644
--- a/include/drm/drm_connector.h
+++ b/include/drm/drm_connector.h
@@ -1193,4 +1193,15 @@ void drm_connector_list_iter_end(struct drm_connector_list_iter *iter);
 #define drm_for_each_connector_iter(connector, iter) \
 	while ((connector = drm_connector_list_iter_next(iter)))
 
+/**
+ * drm_for_each_connector_encoder_ids - iterate connector encoder_ids[]
+ * @connector: &struct drm_connector pointer used as cursor
+ * @encoder_id: the encoder ID
+ * @__i: int iteration cursor, for macro-internal use
+ */
+#define drm_for_each_connector_encoder_ids(connector, encoder_id, __i) \
+	for ((__i) = 0; (__i) < ARRAY_SIZE((connector)->encoder_ids) && \
+		     (connector)->encoder_ids[(__i)] != 0; (__i)++) \
+		for_each_if((encoder_id) = (connector)->encoder_ids[(__i)])
+
 #endif
-- 
2.16.4