[PATCH/RFC 1/4] clk: Add CLK_RUNTIME_PM and clk_may_runtime_pm()

Geert Uytterhoeven
2014-04-24T10:13:48Z

Add a flag CLK_RUNTIME_PM, to let low-level clock drivers indicate that
a clock is suitable for Runtime PM.
Add clk_may_runtime_pm(), to get the status of the flag.

This will allow the device core to enable automatic Runtime PM management
for devices tied to clocks that are suitable for Runtime PM.

Signed-off-by: Geert Uytterhoeven <geert+renesas@glider.be>
---
drivers/clk/clk.c | 12 ++++++++++++
include/linux/clk-provider.h | 1 +
include/linux/clk.h | 1 +
3 files changed, 14 insertions(+)

diff --git a/drivers/clk/clk.c b/drivers/clk/clk.c
index 0b2819551756..a83a2cc0af67 100644
--- a/drivers/clk/clk.c
+++ b/drivers/clk/clk.c
@@ -1115,6 +1115,18 @@ long clk_get_accuracy(struct clk *clk)
EXPORT_SYMBOL_GPL(clk_get_accuracy);

/**
+ * clk_may_runtime_pm - check if the clock is suitable for Runtime PM
+ * @clk: the clock to check
+ *
+ * Return true if the clock is suitable for Runtime PM
+ * Return false if clk is NULL, or if the clock is not suitable for Runtime PM.
+ */
+bool clk_may_runtime_pm(const struct clk *clk)
+{
+ return clk && clk->flags & CLK_RUNTIME_PM;
+}
+
+/**
* __clk_recalc_rates
* @clk: first clk in the subtree
* @msg: notification type (see include/linux/clk.h)
diff --git a/include/linux/clk-provider.h b/include/linux/clk-provider.h
index 24c8ba4fa6ae..3ca9a7c1f02d 100644
--- a/include/linux/clk-provider.h
+++ b/include/linux/clk-provider.h
@@ -30,6 +30,7 @@
#define CLK_GET_RATE_NOCACHE BIT(6) /* do not use the cached clk rate */
#define CLK_SET_RATE_NO_REPARENT BIT(7) /* don't re-parent on rate change */
#define CLK_GET_ACCURACY_NOCACHE BIT(8) /* do not use the cached clk accuracy */
+#define CLK_RUNTIME_PM BIT(9) /* clock is suitable for Runtime PM */

struct clk_hw;
struct dentry;
diff --git a/include/linux/clk.h b/include/linux/clk.h
index d030fce1d77e..07f156580064 100644
--- a/include/linux/clk.h
+++ b/include/linux/clk.h
@@ -106,6 +106,7 @@ int clk_notifier_unregister(struct clk *clk, struct notifier_block *nb);
*/
long clk_get_accuracy(struct clk *clk);

+bool clk_may_runtime_pm(const struct clk *clk);
#else /* !CONFIG_COMMON_CLK */

static inline long clk_get_accuracy(struct clk *clk)
--
1.7.9.5