Merge branch 'clkdev' of git://git.linaro.org/people/rmk/linux-arm

Pull clkdev updates from Russell King:
 "This supplements clkdev with a device-managed API, allowing drivers
  cleanup paths to be simplified.  We also optimize clk_find() so that
  it exits as soon as it finds a perfect match, and we provide a way to
  minimise the amount of code platforms need to register clkdev entries.

  Some of the code in arm-soc depends on these changes."

* 'clkdev' of git://git.linaro.org/people/rmk/linux-arm:
  CLKDEV: provide helpers for common clock framework
  ARM: 7392/1: CLKDEV: Optimize clk_find()
  ARM: 7376/1: clkdev: Implement managed clk_get()

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()

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)
+			if (match != best_possible)
-				best = match;
+				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
+static struct clk_lookup * __init_refok
-clkdev_alloc(struct clk *clk, const char *con_id, const char *dev_fmt, ...)
+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);

include/linux/clk.h

@@ -100,6 +100,26 @@ 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.

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