lkml.org 
[lkml]   [2015]   [Oct]   [15]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
 
Messages in this thread
Patch in this message
/
From
Subject[PATCH] clk: Make of_clk_get_parent_name() robust with #clock-cells = 1
Date
If a clock provider has #clock-cells = 1 and we call
of_clk_get_parent_name() on it we may end up returning the name
of the provider node if the provider doesn't have a
clock-output-names property. This doesn't make sense, especially
when you consider that calling of_clk_get_parent_name() on such a
node with different indices will return the same name each time.

Let's try getting the clock from the framework via of_clk_get()
instead, and only fallback to the node name if we have a provider
with #clock-cells = 0. This way, we can't hand out the same name
for different clocks when we don't actually know their names.

Signed-off-by: Stephen Boyd <sboyd@codeaurora.org>
---
drivers/clk/clk.c | 22 ++++++++++++++++++++--
1 file changed, 20 insertions(+), 2 deletions(-)

diff --git a/drivers/clk/clk.c b/drivers/clk/clk.c
index b005f666e3a1..a0fe9ca1f0af 100644
--- a/drivers/clk/clk.c
+++ b/drivers/clk/clk.c
@@ -3055,6 +3055,7 @@ const char *of_clk_get_parent_name(struct device_node *np, int index)
u32 pv;
int rc;
int count;
+ struct clk *clk;

if (index < 0)
return NULL;
@@ -3080,8 +3081,25 @@ const char *of_clk_get_parent_name(struct device_node *np, int index)

if (of_property_read_string_index(clkspec.np, "clock-output-names",
index,
- &clk_name) < 0)
- clk_name = clkspec.np->name;
+ &clk_name) < 0) {
+ /*
+ * Best effort to get the name if the clock has been
+ * registered with the framework. If the clock isn't
+ * registered, we return the node name as the name of
+ * the clock as long as #clock-cells = 0.
+ */
+ clk = of_clk_get_from_provider(&clkspec);
+ if (IS_ERR(clk)) {
+ if (clkspec.args_count == 0)
+ clk_name = clkspec.np->name;
+ else
+ clk_name = NULL;
+ } else {
+ clk_name = __clk_get_name(clk);
+ clk_put(clk);
+ }
+ }
+

of_node_put(clkspec.np);
return clk_name;
--
The Qualcomm Innovation Center, Inc. is a member of the Code Aurora Forum,
a Linux Foundation Collaborative Project


\
 
 \ /
  Last update: 2015-10-16 01:41    [W:0.127 / U:1.116 seconds]
©2003-2020 Jasper Spaans|hosted at Digital Ocean and TransIP|Read the blog|Advertise on this site