[f] revise DM_ALLOW_MULTIPLE_DRIVERS for SJG-comments

3 files changed, 55 insertions, 39 deletions

diff --git a/drivers/core/Kconfig b/drivers/core/Kconfig
index 913101ce87..4af8505695 100644
--- a/drivers/core/Kconfig
+++ b/drivers/core/Kconfig
@@ -34,7 +34,6 @@ config DM_WARN
 config DM_ALLOW_MULTIPLE_DRIVERS
         bool "Allow multiple drivers to bind for one node"
 	depends on DM
-	default n
 	help
 	  The driver model in U-Boot originally did not allow multiple
 	  drivers to bind for a single device node.
diff --git a/drivers/core/lists.c b/drivers/core/lists.c
index 912469381b..af1657c6e2 100644
--- a/drivers/core/lists.c
+++ b/drivers/core/lists.c
@@ -126,15 +126,55 @@ static int driver_check_compatible(const struct udevice_id *of_match,
 	return -ENOENT;
 }
 
-int lists_bind_fdt(struct udevice *parent, const void *blob, int offset,
-		   struct udevice **devp)
+static bool driver_bind_next(struct driver **entryp, struct udevice *parent,
+			     const char *name, int offset, const char *compat,
+			     struct udevice **devp)
 {
 	struct driver *driver = ll_entry_start(struct driver, driver);
 	const int n_ents = ll_entry_count(struct driver, driver);
+	struct driver *entry = *entryp;
+	struct udevice *dev;
 	const struct udevice_id *id;
+	bool found = false;
+	int ret;
+
+	for (; entry != driver + n_ents; entry++) {
+		ret = driver_check_compatible(entry->of_match, &id,
+					      compat);
+		if (!ret)
+			break;
+	}
+
+	if (entry == driver + n_ents) {
+		*entryp = NULL;
+		return false;
+	}
+
+	dm_dbg("   - found match at '%s'\n", entry->name);
+	ret = device_bind_with_driver_data(parent, entry, name,
+					   id->data, offset, &dev);
+	if (ret == -ENODEV)
+		dm_dbg("Driver '%s' refuses to bind\n", entry->name);
+
+	if (ret) {
+		dm_warn("Error binding driver '%s': %d\n", entry->name, ret);
+	} else {
+		found = true;
+		if (devp)
+			*devp = dev;
+	}
+
+	*entryp = entry + 1; /* advance onto the next element */
+	return found;
+}
+
+int lists_bind_fdt(struct udevice *parent, const void *blob, int offset,
+		   struct udevice **devp)
+{
+	struct driver *driver = ll_entry_start(struct driver, driver);
 	struct driver *entry;
-	struct udevice *dev;
 	bool found = false;
+	bool allow_multiple = CONFIG_IS_ENABLED(DM_ALLOW_MULTIPLE_DRIVERS);
 	const char *name, *compat_list, *compat;
 	int compat_length, i;
 	int result = 0;
@@ -166,42 +206,13 @@ int lists_bind_fdt(struct udevice *parent, const void *blob, int offset,
 		dm_dbg("   - attempt to match compatible string '%s'\n",
 		       compat);
 
-		entry = driver;
-#if defined(CONFIG_DM_ALLOW_MULTIPLE_DRIVERS)
-allow_more_matches:
-#endif
-		for (; entry != driver + n_ents; entry++) {
-			ret = driver_check_compatible(entry->of_match, &id,
-						      compat);
-			if (!ret)
-				break;
-		}
-		if (entry == driver + n_ents)
-			continue;
-
-		dm_dbg("   - found match at '%s'\n", entry->name);
-		ret = device_bind_with_driver_data(parent, entry, name,
-						   id->data, offset, &dev);
-		if (ret == -ENODEV) {
-			dm_dbg("Driver '%s' refuses to bind\n", entry->name);
-			continue;
-		}
-		if (ret) {
-			dm_warn("Error binding driver '%s': %d\n", entry->name,
-				ret);
-			return ret;
-		} else {
-			found = true;
-			if (devp)
-				*devp = dev;
-#if defined(CONFIG_DM_ALLOW_MULTIPLE_DRIVERS)
-			else {
-				entry++;
-				goto allow_more_matches;
-			}
-#endif
+		for (entry = driver; entry;) {
+			found = driver_bind_next(&entry, parent, name,
+						 offset, compat, devp);
+
+			if (found && (devp || !allow_multiple))
+				return 0;
 		}
-		break;
 	}
 
 	if (!found && !result && ret != -ENODEV)
diff --git a/include/dm/lists.h b/include/dm/lists.h
index 4513d6a311..e300f4f4c9 100644
--- a/include/dm/lists.h
+++ b/include/dm/lists.h
@@ -65,6 +65,12 @@ int lists_bind_fdt(struct udevice *parent, const void *blob, int offset,
  *
  * This binds a new device to a driver.
  *
+ * If DM_ALLOW_MULTIPLE_DRIVERS is configured and devp is NULL, it
+ * will continue through the list of drivers and bind all drivers that
+ * match the compatible string.  If not configured or devp is
+ * non-NULL, it will stop after the first driver that successfully
+ * binds.
+ *
  * @parent:	Parent device
  * @drv_name:	Name of driver to attach to this parent
  * @dev_name:	Name of the new device thus created