diff options
Diffstat (limited to 'include/hw/clock.h')
| -rw-r--r-- | include/hw/clock.h | 21 |
1 files changed, 19 insertions, 2 deletions
diff --git a/include/hw/clock.h b/include/hw/clock.h index e5f45e2626..282a37f7c5 100644 --- a/include/hw/clock.h +++ b/include/hw/clock.h @@ -22,7 +22,17 @@ #define TYPE_CLOCK "clock" OBJECT_DECLARE_SIMPLE_TYPE(Clock, CLOCK) -typedef void ClockCallback(void *opaque); +/* + * Argument to ClockCallback functions indicating why the callback + * has been called. A mask of these values logically ORed together + * is used to specify which events are interesting when the callback + * is registered, so these values must all be different bit values. + */ +typedef enum ClockEvent { + ClockUpdate = 1, /* Clock period has just updated */ +} ClockEvent; + +typedef void ClockCallback(void *opaque, ClockEvent event); /* * clock store a value representing the clock's period in 2^-32ns unit. @@ -50,6 +60,7 @@ typedef void ClockCallback(void *opaque); * @canonical_path: clock path string cache (used for trace purpose) * @callback: called when clock changes * @callback_opaque: argument for @callback + * @callback_events: mask of events when callback should be called * @source: source (or parent in clock tree) of the clock * @children: list of clocks connected to this one (it is their source) * @sibling: structure used to form a clock list @@ -67,6 +78,7 @@ struct Clock { char *canonical_path; ClockCallback *callback; void *callback_opaque; + unsigned int callback_events; /* Clocks are organized in a clock tree */ Clock *source; @@ -114,10 +126,15 @@ Clock *clock_new(Object *parent, const char *name); * @clk: the clock to register the callback into * @cb: the callback function * @opaque: the argument to the callback + * @events: the events the callback should be called for + * (logical OR of ClockEvent enum values) * * Register a callback called on every clock update. + * Note that a clock has only one callback: you cannot register + * different callback functions for different events. */ -void clock_set_callback(Clock *clk, ClockCallback *cb, void *opaque); +void clock_set_callback(Clock *clk, ClockCallback *cb, + void *opaque, unsigned int events); /** * clock_clear_callback: |