From: Stephen Warren <swarren@nvidia.com>
Date: Fri, 3 Jan 2014 03:10:24 +0000 (+1100)
Subject: rtc-honor-device-tree-alias-entries-when-assigning-ids-v2
X-Git-Tag: next-20140106~2^2~58
X-Git-Url: https://git.karo-electronics.de/?a=commitdiff_plain;h=d062871ff59b692b78c69b9f8545397957663dc2;p=karo-tx-linux.git

rtc-honor-device-tree-alias-entries-when-assigning-ids-v2

v2: Explicitly check for both dev->of_node and dev->parent->of_node.
    This covers the MFD case, without the MFD core having to set
    child MFD devices' of_node pointer to the same node as the top-
    level MFD device, which causes problems such as:
    http://www.spinics.net/lists/arm-kernel/msg295854.html

Signed-off-by: Stephen Warren <swarren@nvidia.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
---

diff --git a/drivers/rtc/class.c b/drivers/rtc/class.c
index 7989b5d030cb..589351ef75d0 100644
--- a/drivers/rtc/class.c
+++ b/drivers/rtc/class.c
@@ -158,17 +158,19 @@ struct rtc_device *rtc_device_register(const char *name, struct device *dev,
 {
 	struct rtc_device *rtc;
 	struct rtc_wkalrm alrm;
-	int of_id, id = -1, err;
+	int of_id = -1, id = -1, err;
 
-	if (dev->of_node) {
+	if (dev->of_node)
 		of_id = of_alias_get_id(dev->of_node, "rtc");
-		if (of_id >= 0) {
-			id = ida_simple_get(&rtc_ida, of_id, of_id + 1,
-					    GFP_KERNEL);
-			if (id < 0)
-				dev_warn(dev, "/aliases ID %d not available\n",
-					 of_id);
-		}
+	else if (dev->parent && dev->parent->of_node)
+		of_id = of_alias_get_id(dev->parent->of_node, "rtc");
+
+	if (of_id >= 0) {
+		id = ida_simple_get(&rtc_ida, of_id, of_id + 1,
+				    GFP_KERNEL);
+		if (id < 0)
+			dev_warn(dev, "/aliases ID %d not available\n",
+				    of_id);
 	}
 
 	if (id < 0) {