4 files changed, 171 insertions, 10 deletions

diff --git a/Documentation/driver-model/devres.txt b/Documentation/driver-model/devres.txt
index 2a596a4fc23e..9faac6ae3525 100644
--- a/Documentation/driver-model/devres.txt
+++ b/Documentation/driver-model/devres.txt
@@ -276,3 +276,7 @@ REGULATOR
   devm_regulator_get()
   devm_regulator_put()
   devm_regulator_bulk_get()
+
+CLOCK
+  devm_clk_get()
+  devm_clk_put()
diff --git a/drivers/clk/clkdev.c b/drivers/clk/clkdev.c
index 6db161f64ae0..c535cf8c5770 100644
--- a/drivers/clk/clkdev.c
+++ b/drivers/clk/clkdev.c
@@ -35,7 +35,12 @@ static DEFINE_MUTEX(clocks_mutex);
 static struct clk_lookup *clk_find(const char *dev_id, const char *con_id)
 {
         struct clk_lookup *p, *cl = NULL;
-        int match, best = 0;
+        int match, best_found = 0, best_possible = 0;
+
+        if (dev_id)
+                best_possible += 2;
+        if (con_id)
+                best_possible += 1;
 
         list_for_each_entry(p, &clocks, node) {
                 match = 0;
@@ -50,10 +55,10 @@ static struct clk_lookup *clk_find(const char *dev_id, const char *con_id)
                         match += 1;
                 }
 
-                if (match > best) {
+                if (match > best_found) {
                         cl = p;
-                        if (match != 3)
-                                best = match;
+                        if (match != best_possible)
+                                best_found = match;
                         else
                                 break;
                 }
@@ -89,6 +94,51 @@ void clk_put(struct clk *clk)
 }
 EXPORT_SYMBOL(clk_put);
 
+static void devm_clk_release(struct device *dev, void *res)
+{
+        clk_put(*(struct clk **)res);
+}
+
+struct clk *devm_clk_get(struct device *dev, const char *id)
+{
+        struct clk **ptr, *clk;
+
+        ptr = devres_alloc(devm_clk_release, sizeof(*ptr), GFP_KERNEL);
+        if (!ptr)
+                return ERR_PTR(-ENOMEM);
+
+        clk = clk_get(dev, id);
+        if (!IS_ERR(clk)) {
+                *ptr = clk;
+                devres_add(dev, ptr);
+        } else {
+                devres_free(ptr);
+        }
+
+        return clk;
+}
+EXPORT_SYMBOL(devm_clk_get);
+
+static int devm_clk_match(struct device *dev, void *res, void *data)
+{
+        struct clk **c = res;
+        if (!c || !*c) {
+                WARN_ON(!c || !*c);
+                return 0;
+        }
+        return *c == data;
+}
+
+void devm_clk_put(struct device *dev, struct clk *clk)
+{
+        int ret;
+
+        ret = devres_destroy(dev, devm_clk_release, devm_clk_match, clk);
+
+        WARN_ON(ret);
+}
+EXPORT_SYMBOL(devm_clk_put);
+
 void clkdev_add(struct clk_lookup *cl)
 {
         mutex_lock(&clocks_mutex);
@@ -116,8 +166,9 @@ struct clk_lookup_alloc {
         char    con_id[MAX_CON_ID];
 };
 
-struct clk_lookup * __init_refok
-clkdev_alloc(struct clk *clk, const char *con_id, const char *dev_fmt, ...)
+static struct clk_lookup * __init_refok
+vclkdev_alloc(struct clk *clk, const char *con_id, const char *dev_fmt,
+        va_list ap)
 {
         struct clk_lookup_alloc *cla;
 
@@ -132,16 +183,25 @@ clkdev_alloc(struct clk *clk, const char *con_id, const char *dev_fmt, ...)
         }
 
         if (dev_fmt) {
-                va_list ap;
-
-                va_start(ap, dev_fmt);
                 vscnprintf(cla->dev_id, sizeof(cla->dev_id), dev_fmt, ap);
                 cla->cl.dev_id = cla->dev_id;
-                va_end(ap);
         }
 
         return &cla->cl;
 }
+
+struct clk_lookup * __init_refok
+clkdev_alloc(struct clk *clk, const char *con_id, const char *dev_fmt, ...)
+{
+        struct clk_lookup *cl;
+        va_list ap;
+
+        va_start(ap, dev_fmt);
+        cl = vclkdev_alloc(clk, con_id, dev_fmt, ap);
+        va_end(ap);
+
+        return cl;
+}
 EXPORT_SYMBOL(clkdev_alloc);
 
 int clk_add_alias(const char *alias, const char *alias_dev_name, char *id,
@@ -173,3 +233,65 @@ void clkdev_drop(struct clk_lookup *cl)
         kfree(cl);
 }
 EXPORT_SYMBOL(clkdev_drop);
+
+/**
+ * clk_register_clkdev - register one clock lookup for a struct clk
+ * @clk: struct clk to associate with all clk_lookups
+ * @con_id: connection ID string on device
+ * @dev_id: format string describing device name
+ *
+ * con_id or dev_id may be NULL as a wildcard, just as in the rest of
+ * clkdev.
+ *
+ * To make things easier for mass registration, we detect error clks
+ * from a previous clk_register() call, and return the error code for
+ * those.  This is to permit this function to be called immediately
+ * after clk_register().
+ */
+int clk_register_clkdev(struct clk *clk, const char *con_id,
+        const char *dev_fmt, ...)
+{
+        struct clk_lookup *cl;
+        va_list ap;
+
+        if (IS_ERR(clk))
+                return PTR_ERR(clk);
+
+        va_start(ap, dev_fmt);
+        cl = vclkdev_alloc(clk, con_id, dev_fmt, ap);
+        va_end(ap);
+
+        if (!cl)
+                return -ENOMEM;
+
+        clkdev_add(cl);
+
+        return 0;
+}
+
+/**
+ * clk_register_clkdevs - register a set of clk_lookup for a struct clk
+ * @clk: struct clk to associate with all clk_lookups
+ * @cl: array of clk_lookup structures with con_id and dev_id pre-initialized
+ * @num: number of clk_lookup structures to register
+ *
+ * To make things easier for mass registration, we detect error clks
+ * from a previous clk_register() call, and return the error code for
+ * those.  This is to permit this function to be called immediately
+ * after clk_register().
+ */
+int clk_register_clkdevs(struct clk *clk, struct clk_lookup *cl, size_t num)
+{
+        unsigned i;
+
+        if (IS_ERR(clk))
+                return PTR_ERR(clk);
+
+        for (i = 0; i < num; i++, cl++) {
+                cl->clk = clk;
+                clkdev_add(cl);
+        }
+
+        return 0;
+}
+EXPORT_SYMBOL(clk_register_clkdevs);
diff --git a/include/linux/clk.h b/include/linux/clk.h
index 0e078bdec09f..ad5c43e8ae8a 100644
--- a/include/linux/clk.h
+++ b/include/linux/clk.h
@@ -101,6 +101,26 @@ int clk_notifier_unregister(struct clk *clk, struct notifier_block *nb);
 struct clk *clk_get(struct device *dev, const char *id);
 
 /**
+ * devm_clk_get - lookup and obtain a managed reference to a clock producer.
+ * @dev: device for clock "consumer"
+ * @id: clock comsumer ID
+ *
+ * Returns a struct clk corresponding to the clock producer, or
+ * valid IS_ERR() condition containing errno.  The implementation
+ * uses @dev and @id to determine the clock consumer, and thereby
+ * the clock producer.  (IOW, @id may be identical strings, but
+ * clk_get may return different clock producers depending on @dev.)
+ *
+ * Drivers must assume that the clock source is not enabled.
+ *
+ * devm_clk_get should not be called from within interrupt context.
+ *
+ * The clock will automatically be freed when the device is unbound
+ * from the bus.
+ */
+struct clk *devm_clk_get(struct device *dev, const char *id);
+
+/**
  * clk_prepare - prepare a clock source
  * @clk: clock source
  *
@@ -206,6 +226,18 @@ unsigned long clk_get_rate(struct clk *clk);
  */
 void clk_put(struct clk *clk);
 
+/**
+ * devm_clk_put - "free" a managed clock source
+ * @dev: device used to acuqire the clock
+ * @clk: clock source acquired with devm_clk_get()
+ *
+ * Note: drivers must ensure that all clk_enable calls made on this
+ * clock source are balanced by clk_disable calls prior to calling
+ * this function.
+ *
+ * clk_put should not be called from within interrupt context.
+ */
+void devm_clk_put(struct device *dev, struct clk *clk);
 
 /*
  * The remaining APIs are optional for machine class support.
diff --git a/include/linux/clkdev.h b/include/linux/clkdev.h
index d9a4fd028c9d..a6a6f603103b 100644
--- a/include/linux/clkdev.h
+++ b/include/linux/clkdev.h
@@ -40,4 +40,7 @@ void clkdev_drop(struct clk_lookup *cl);
 void clkdev_add_table(struct clk_lookup *, size_t);
 int clk_add_alias(const char *, const char *, char *, struct device *);
 
+int clk_register_clkdev(struct clk *, const char *, const char *, ...);
+int clk_register_clkdevs(struct clk *, struct clk_lookup *, size_t);
+
 #endif