CLKDEV: provide helpers for common clock framework

The common clock framework allocates clocks dynamically.  Provide a
set of helpers to streamline the clkdev registration of the clock
lookups to avoid repetitive code sequences.

Reviewed-by: Viresh Kumar <viresh.kumar@st.com>
Tested-by: Shawn Guo <shawn.guo@linaro.org>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>

diff --git a/drivers/clk/clkdev.c b/drivers/clk/clkdev.c
index d4a59931e75ef8807c7787d3425c9e09cc75209f..c535cf8c5770f2bd154f391ade6fcd9f7fa888d2 100644 (file)
--- a/drivers/clk/clkdev.c
+++ b/drivers/clk/clkdev.c
@@ -166,8 +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;
 
@@ -182,16 +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,
@@ -223,3 +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/clkdev.h b/include/linux/clkdev.h
index d9a4fd028c9dc0c019f1fe1df48b8c7782c90d32..a6a6f603103be9903caf75180b71f3499a48d047 100644 (file)
--- 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