[PATCH 06/10] clk: Add support for a generic clock multiplexer

Russell King - ARM Linux
2011-04-18T18:41:38Z

On Mon, Apr 18, 2011 at 07:34:21PM +0100, Russell King - ARM Linux wrote:
> Oops, clk_get_sys() and clk_find() really should be fixed for this. I'll
> sort a patch for it.

And here it is:

8<----
Subject: [PATCH] Fix clkdev return value for NULL clk case

clkdev may incorrectly cause a clkdev entry with a NULL clk to return
-ENOENT. This is not the intention of this code; -ENOENT should only
be returned if the clock entry can not be found in the table. Fix this.

Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
---
drivers/clk/clkdev.c | 19 +++++++++----------
1 file changed, 9 insertions(+), 10 deletions(-)

diff --git a/drivers/clk/clkdev.c b/drivers/clk/clkdev.c
index 0fc0a79..36a134f 100644
--- a/drivers/clk/clkdev.c
+++ b/drivers/clk/clkdev.c
@@ -32,10 +32,9 @@ static DEFINE_MUTEX(clocks_mutex);
* Then we take the most specific entry - with the following
* order of precedence: dev+con > dev only > con only.
*/
-static struct clk *clk_find(const char *dev_id, const char *con_id)
+static struct clk_lookup *clk_find(const char *dev_id, const char *con_id)
{
- struct clk_lookup *p;
- struct clk *clk = NULL;
+ struct clk_lookup *p, *cl = NULL;
int match, best = 0;

list_for_each_entry(p, &clocks, node) {
@@ -52,27 +51,27 @@ static struct clk *clk_find(const char *dev_id, const char *con_id)
}

if (match > best) {
- clk = p->clk;
+ cl = p;
if (match != 3)
best = match;
else
break;
}
}
- return clk;
+ return cl;
}

struct clk *clk_get_sys(const char *dev_id, const char *con_id)
{
- struct clk *clk;
+ struct clk_lookup *cl;

mutex_lock(&clocks_mutex);
- clk = clk_find(dev_id, con_id);
- if (clk && !__clk_get(clk))
- clk = NULL;
+ cl = clk_find(dev_id, con_id);
+ if (cl && !__clk_get(cl->clk))
+ cl = NULL;
mutex_unlock(&clocks_mutex);

- return clk ? clk : ERR_PTR(-ENOENT);
+ return cl ? cl->clk : ERR_PTR(-ENOENT);
}
EXPORT_SYMBOL(clk_get_sys);