From: Peter De Schrijver <pdeschrijver@nvidia.com>
Date: Tue, 21 Mar 2017 10:16:26 +0000 (+0200)
Subject: clk: aggregate return codes of notify chains
X-Git-Tag: v4.14-rc1~926^2~45
X-Git-Url: http://review.tizen.org/git/?a=commitdiff_plain;h=17c34c566795ca7529cf888fb33fdb7997d6b202;p=platform%2Fkernel%2Flinux-rpi.git

clk: aggregate return codes of notify chains

In case there are multiple notify chains for the same clocks (because they
were registered by different users), we need to propagate potential failure
of any single one of them to the caller. Otherwise we eg risk violating the
V/f curve when a notifier is used for DVFS.

Signed-off-by: Peter De Schrijver <pdeschrijver@nvidia.com>
Signed-off-by: Stephen Boyd <sboyd@codeaurora.org>
Signed-off-by: Michael Turquette <mturquette@baylibre.com>
---

diff --git a/drivers/clk/clk.c b/drivers/clk/clk.c
index 0d8eb5a..cddddbe 100644
--- a/drivers/clk/clk.c
+++ b/drivers/clk/clk.c
@@ -966,6 +966,8 @@ static int __clk_notify(struct clk_core *core, unsigned long msg,
 			cnd.clk = cn->clk;
 			ret = srcu_notifier_call_chain(&cn->notifier_head, msg,
 					&cnd);
+			if (ret & NOTIFY_STOP_MASK)
+				return ret;
 		}
 	}