clocksource: Cleanup struct clocksource and documentation

 *	Provides mostly state-free accessors to the underlying hardware.

 *	This is the structure used for system time.

 *

 * @name:		ptr to clocksource name

 * @list:		list head for registration

 * @rating:		rating value for selection (higher is better)

 * @read:		Returns a cycle value, passes clocksource as argument

 * @mask:		Bitmask for two's complement

 *			subtraction of non 64 bit counters

 * @mult:		Cycle to nanosecond multiplier

 * @shift:		Cycle to nanosecond divisor (power of two)

 * @max_idle_ns:	Maximum idle time permitted by the clocksource (nsecs)

 * @maxadj:		Maximum adjustment value to mult (~11%)

 * @archdata:		Optional arch-specific data

 * @max_cycles:		Maximum safe cycle value which won't overflow on

 *			multiplication

 * @name:		Pointer to clocksource name

 * @list:		List head for registration (internal)

 * @rating:		Rating value for selection (higher is better)

 *			To avoid rating inflation the following

 *			list should give you a guide as to how

 *			to assign your clocksource a rating

 *			400-499: Perfect

 *				The ideal clocksource. A must-use where

 *				available.

 * @read:		returns a cycle value, passes clocksource as argument

 * @enable:		optional function to enable the clocksource

 * @disable:		optional function to disable the clocksource

 * @mask:		bitmask for two's complement

 *			subtraction of non 64 bit counters

 * @mult:		cycle to nanosecond multiplier

 * @shift:		cycle to nanosecond divisor (power of two)

 * @max_idle_ns:	max idle time permitted by the clocksource (nsecs)

 * @maxadj:		maximum adjustment value to mult (~11%)

 * @max_cycles:		maximum safe cycle value which won't overflow on multiplication

 * @flags:		flags describing special properties

 * @archdata:		arch-specific data

 * @suspend:		suspend function for the clocksource, if necessary

 * @resume:		resume function for the clocksource, if necessary

 * @flags:		Flags describing special properties

 * @enable:		Optional function to enable the clocksource

 * @disable:		Optional function to disable the clocksource

 * @suspend:		Optional suspend function for the clocksource

 * @resume:		Optional resume function for the clocksource

 * @mark_unstable:	Optional function to inform the clocksource driver that

 *			the watchdog marked the clocksource unstable

 * @owner:		module reference, must be set by clocksource in modules

 * @tick_stable:        Optional function called periodically from the watchdog

 *			code to provide stable syncrhonization points

 * @wd_list:		List head to enqueue into the watchdog list (internal)

 * @cs_last:		Last clocksource value for clocksource watchdog

 * @wd_last:		Last watchdog value corresponding to @cs_last

 * @owner:		Module reference, must be set by clocksource in modules

 *

 * Note: This struct is not used in hotpathes of the timekeeping code

 * because the timekeeper caches the hot path fields in its own data

 * structure, so no line cache alignment is required,

 * structure, so no cache line alignment is required,

 *

 * The pointer to the clocksource itself is handed to the read

 * callback. If you need extra information there you can wrap struct

	const char		*name;

	struct list_head	list;

	int			rating;

	unsigned long		flags;

	int			(*enable)(struct clocksource *cs);

	void			(*disable)(struct clocksource *cs);

	unsigned long flags;

	void			(*suspend)(struct clocksource *cs);

	void			(*resume)(struct clocksource *cs);

	void			(*mark_unstable)(struct clocksource *cs);