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-rw-r--r--Documentation/clk.txt46
1 files changed, 26 insertions, 20 deletions
diff --git a/Documentation/clk.txt b/Documentation/clk.txt
index 6f68ba0d1e01..3aeb5c440442 100644
--- a/Documentation/clk.txt
+++ b/Documentation/clk.txt
@@ -70,6 +70,10 @@ the operations defined in clk.h:
unsigned long parent_rate);
long (*round_rate)(struct clk_hw *hw, unsigned long,
unsigned long *);
+ long (*determine_rate)(struct clk_hw *hw,
+ unsigned long rate,
+ unsigned long *best_parent_rate,
+ struct clk **best_parent_clk);
int (*set_parent)(struct clk_hw *hw, u8 index);
u8 (*get_parent)(struct clk_hw *hw);
int (*set_rate)(struct clk_hw *hw, unsigned long);
@@ -179,26 +183,28 @@ mandatory, a cell marked as "n" implies that either including that
callback is invalid or otherwise unnecessary. Empty cells are either
optional or must be evaluated on a case-by-case basis.
- clock hardware characteristics
- -----------------------------------------------------------
- | gate | change rate | single parent | multiplexer | root |
- |------|-------------|---------------|-------------|------|
-.prepare | | | | | |
-.unprepare | | | | | |
- | | | | | |
-.enable | y | | | | |
-.disable | y | | | | |
-.is_enabled | y | | | | |
- | | | | | |
-.recalc_rate | | y | | | |
-.round_rate | | y | | | |
-.set_rate | | y | | | |
- | | | | | |
-.set_parent | | | n | y | n |
-.get_parent | | | n | y | n |
- | | | | | |
-.init | | | | | |
- -----------------------------------------------------------
+ clock hardware characteristics
+ -----------------------------------------------------------
+ | gate | change rate | single parent | multiplexer | root |
+ |------|-------------|---------------|-------------|------|
+.prepare | | | | | |
+.unprepare | | | | | |
+ | | | | | |
+.enable | y | | | | |
+.disable | y | | | | |
+.is_enabled | y | | | | |
+ | | | | | |
+.recalc_rate | | y | | | |
+.round_rate | | y [1] | | | |
+.determine_rate | | y [1] | | | |
+.set_rate | | y | | | |
+ | | | | | |
+.set_parent | | | n | y | n |
+.get_parent | | | n | y | n |
+ | | | | | |
+.init | | | | | |
+ -----------------------------------------------------------
+[1] either one of round_rate or determine_rate is required.
Finally, register your clock at run-time with a hardware-specific
registration function. This function simply populates struct clk_foo's
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