Commit 9f1612d3 authored Jul 18, 2012 by Shawn Guo Committed by Mike Turquette Jul 19, 2012

clk: fix clk_get on of_clk_get_by_name return check



The commit 766e6a4e (clk: add DT clock binding support) plugs device
tree clk lookup of_clk_get_by_name into clk_get, and fall on non-DT
lookup clk_get_sys if DT lookup fails.

The return check on of_clk_get_by_name takes (clk != NULL) as a
successful DT lookup.  But it's not the case.  For any system that
does not define clk lookup in device tree, ERR_PTR(-ENOENT) will be
returned, and consequently, all the client drivers calling clk_get
in their probe functions will fail to probe with error code -ENOENT
returned.

Fix the issue by checking of_clk_get_by_name return with !IS_ERR(clk),
and update of_clk_get and of_clk_get_by_name for !CONFIG_OF build
correspondingly.

Signed-off-by: Shawn Guo <shawn.guo@linaro.org>
Acked-by: Rob Herring <rob.herring@calxeda.com>
Tested-by: Marek Vasut <marex@denx.de>
Tested-by: Lauri Hintsala <lauri.hintsala@bluegiga.com>
Signed-off-by: Mike Turquette <mturquette@linaro.org>

parent c782c384

drivers/clk/clkdev.c

+1 −1

Original line number	Diff line number	Diff line
		@@ -157,7 +157,7 @@ struct clk clk_get(struct device dev, const char *con_id)

		if (dev) {
		clk = of_clk_get_by_name(dev->of_node, con_id);
		if (clk && __clk_get(clk))
		if (!IS_ERR(clk) && __clk_get(clk))
		return clk;
		}

include/linux/clk.h

+3 −2

Original line number	Diff line number	Diff line
		@@ -12,6 +12,7 @@
		#ifndef __LINUX_CLK_H
		#define __LINUX_CLK_H

		#include <linux/err.h>
		#include <linux/kernel.h>
		#include <linux/notifier.h>

		@@ -320,12 +321,12 @@ struct clk of_clk_get_from_provider(struct of_phandle_args clkspec);
		#else
		static inline struct clk of_clk_get(struct device_node np, int index)
		{
		return NULL;
		return ERR_PTR(-ENOENT);
		}
		static inline struct clk of_clk_get_by_name(struct device_node np,
		const char *name)
		{
		return NULL;
		return ERR_PTR(-ENOENT);
		}
		#endif