[ARM] pxa: fix clock lookup to find specific device clocks

Ensure that the clock lookup always finds an entry for a specific
device and ID before it falls back to finding just by ID.  This
fixes a problem reported by Holger Schurig where the BTUART was
assigned the wrong clock.

Tested-by: Holger Schurig <hs4233@mail.mn-solutions.de>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>

1 files changed, 16 insertions, 7 deletions

diff --git a/arch/arm/mach-pxa/clock.c b/arch/arm/mach-pxa/clock.c
index 83ef5ecaf432..df5ae2710ab1 100644
--- a/arch/arm/mach-pxa/clock.c
+++ b/arch/arm/mach-pxa/clock.c
@@ -23,18 +23,27 @@ static LIST_HEAD(clocks);
 static DEFINE_MUTEX(clocks_mutex);
 static DEFINE_SPINLOCK(clocks_lock);
 
+static struct clk *clk_lookup(struct device *dev, const char *id)
+{
+        struct clk *p;
+
+        list_for_each_entry(p, &clocks, node)
+                if (strcmp(id, p->name) == 0 && p->dev == dev)
+                        return p;
+
+        return NULL;
+}
+
 struct clk *clk_get(struct device *dev, const char *id)
 {
         struct clk *p, *clk = ERR_PTR(-ENOENT);
 
         mutex_lock(&clocks_mutex);
-        list_for_each_entry(p, &clocks, node) {
-                if (strcmp(id, p->name) == 0 &&
-                    (p->dev == NULL || p->dev == dev)) {
-                        clk = p;
-                        break;
-                }
-        }
+        p = clk_lookup(dev, id);
+        if (!p)
+                p = clk_lookup(NULL, id);
+        if (p)
+                clk = p;
         mutex_unlock(&clocks_mutex);
 
         return clk;