clk: Add rate constraints to clocks

Adds a way for clock consumers to set maximum and minimum rates. This
can be used for thermal drivers to set minimum rates, or by misc.
drivers to set maximum rates to assure a minimum performance level.

Changes the signature of the determine_rate callback by adding the
parameters min_rate and max_rate.

Signed-off-by: Tomeu Vizoso <tomeu.vizoso@collabora.com>
Signed-off-by: Stephen Boyd <sboyd@codeaurora.org>
[sboyd@codeaurora.org: set req_rate in __clk_init]
Signed-off-by: Michael Turquette <mturquette@linaro.org>
[mturquette@linaro.org: min/max rate for sun6i_ahb1_clk_determine_rate
                        migrated clk-private.h changes to clk.c]

1 files changed, 2 insertions, 0 deletions

diff --git a/Documentation/clk.txt b/Documentation/clk.txt
index 4ff84623d5e1..0e4f90aa1c13 100644
--- a/Documentation/clk.txt
+++ b/Documentation/clk.txt
@@ -73,6 +73,8 @@ the operations defined in clk.h:
 						unsigned long *parent_rate);
 		long		(*determine_rate)(struct clk_hw *hw,
 						unsigned long rate,
+						unsigned long min_rate,
+						unsigned long max_rate,
 						unsigned long *best_parent_rate,
 						struct clk_hw **best_parent_clk);
 		int		(*set_parent)(struct clk_hw *hw, u8 index);