diff options
Diffstat (limited to 'kernel/Documentation/clk.txt')
| -rw-r--r-- | kernel/Documentation/clk.txt | 35 |
1 files changed, 4 insertions, 31 deletions
diff --git a/kernel/Documentation/clk.txt b/kernel/Documentation/clk.txt index 0e4f90aa1..5c4bc4d01 100644 --- a/kernel/Documentation/clk.txt +++ b/kernel/Documentation/clk.txt @@ -71,12 +71,8 @@ the operations defined in clk.h: long (*round_rate)(struct clk_hw *hw, unsigned long rate, 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 (*determine_rate)(struct clk_hw *hw, + struct clk_rate_request *req); int (*set_parent)(struct clk_hw *hw, u8 index); u8 (*get_parent)(struct clk_hw *hw); int (*set_rate)(struct clk_hw *hw, @@ -230,30 +226,7 @@ clk_register(...) See the basic clock types in drivers/clk/clk-*.c for examples. - Part 5 - static initialization of clock data - -For platforms with many clocks (often numbering into the hundreds) it -may be desirable to statically initialize some clock data. This -presents a problem since the definition of struct clk should be hidden -from everyone except for the clock core in drivers/clk/clk.c. - -To get around this problem struct clk's definition is exposed in -include/linux/clk-private.h along with some macros for more easily -initializing instances of the basic clock types. These clocks must -still be initialized with the common clock framework via a call to -__clk_init. - -clk-private.h must NEVER be included by code which implements struct -clk_ops callbacks, nor must it be included by any logic which pokes -around inside of struct clk at run-time. To do so is a layering -violation. - -To better enforce this policy, always follow this simple rule: any -statically initialized clock data MUST be defined in a separate file -from the logic that implements its ops. Basically separate the logic -from the data and all is well. - - Part 6 - Disabling clock gating of unused clocks + Part 5 - Disabling clock gating of unused clocks Sometimes during development it can be useful to be able to bypass the default disabling of unused clocks. For example, if drivers aren't enabling @@ -264,7 +237,7 @@ are sorted out. To bypass this disabling, include "clk_ignore_unused" in the bootargs to the kernel. - Part 7 - Locking + Part 6 - Locking The common clock framework uses two global locks, the prepare lock and the enable lock. |