clk: add CLK_DEFER_ORPHAN flag to prevent orphans from being used
From: Heiko Stuebner <heiko@...> Date: Thu, 2 Apr 2015 12:24:53 +0200
Commit-Message
The usage of clocks derived from an orphan can produce issues when trying to set rates etc. So ideally a clk_get to such a clock should defer till the clock hierarchy is complete. But as some arches probably rely on such clocks we can't disable them all. Therefore add a new clk flag where arches can enable this behaviour for their clocks. Signed-off-by: Heiko Stuebner <heiko@...>
Patch-Comment
drivers/clk/clk.c | 6 ++++++ include/linux/clk-provider.h | 1 + 2 files changed, 7 insertions(+)
Statistics
- 7 lines added
- 0 lines removed
Changes
------------------------------ drivers/clk/clk.c -------------------------------
index 476f491..8511c62 100644
@@ -3041,6 +3041,12 @@ struct clk *__of_clk_get_from_provider(struct of_phandle_args *clkspec,
if (provider->node == clkspec->np)
clk = provider->get(clkspec, provider->data);
if (!IS_ERR(clk)) {
+ if ((__clk_get_flags(clk) & CLK_DEFER_ORPHAN)
+ && clk_is_orphan(clk)) {
+ clk = ERR_PTR(-EPROBE_DEFER);
+ break;
+ }
+
clk = __clk_create_clk(__clk_get_hw(clk), dev_id,
con_id);
------------------------- include/linux/clk-provider.h -------------------------
index 28abf1b..ef8d669 100644
@@ -31,6 +31,7 @@
#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_DEFER_ORPHAN BIT(9) /* defer clk_get calls for orphans */
struct clk_hw;
struct clk_core;