Commit 373fe0bd authored by Jon Hunter's avatar Jon Hunter
Browse files

ARM: OMAP: Add function to request a timer by capability 



Currently OMAP timers can be requested by requesting any available or by a
numerical device ID. If a specific timer is required because it has a particular
capability, such as can interrupt the on-chip DSP in addition to the ARM CPU,
then the user needs to know the device ID of the timer with this feature.
Therefore, add a new API called omap_dm_timer_request_by_cap() that allows
drivers to request a timer by capability.

Signed-off-by: default avatarJon Hunter <jon-hunter@ti.com>
parent ad24bde8

arch/arm/plat-omap/dmtimer.c

+52 −0
Original line number Diff line number Diff line
@@ -237,6 +237,58 @@ struct omap_dm_timer *omap_dm_timer_request_specific(int id) 
}

EXPORT_SYMBOL_GPL(omap_dm_timer_request_specific);



/**

 * omap_dm_timer_request_by_cap - Request a timer by capability

 * @cap:	Bit mask of capabilities to match

 *

 * Find a timer based upon capabilities bit mask. Callers of this function

 * should use the definitions found in the plat/dmtimer.h file under the

 * comment "timer capabilities used in hwmod database". Returns pointer to

 * timer handle on success and a NULL pointer on failure.

 */

struct omap_dm_timer *omap_dm_timer_request_by_cap(u32 cap)

{

	struct omap_dm_timer *timer = NULL, *t;

	unsigned long flags;



	if (!cap)

		return NULL;



	spin_lock_irqsave(&dm_timer_lock, flags);

	list_for_each_entry(t, &omap_timer_list, node) {

		if ((!t->reserved) && ((t->capability & cap) == cap)) {

			/*

			 * If timer is not NULL, we have already found one timer

			 * but it was not an exact match because it had more

			 * capabilites that what was required. Therefore,

			 * unreserve the last timer found and see if this one

			 * is a better match.

			 */

			if (timer)

				timer->reserved = 0;



			timer = t;

			timer->reserved = 1;



			/* Exit loop early if we find an exact match */

			if (t->capability == cap)

				break;

		}

	}

	spin_unlock_irqrestore(&dm_timer_lock, flags);



	if (timer && omap_dm_timer_prepare(timer)) {

		timer->reserved = 0;

		timer = NULL;

	}



	if (!timer)

		pr_debug("%s: timer request failed!\n", __func__);



	return timer;

}

EXPORT_SYMBOL_GPL(omap_dm_timer_request_by_cap);



int omap_dm_timer_free(struct omap_dm_timer *timer)

{

	if (unlikely(!timer))

arch/arm/plat-omap/include/plat/dmtimer.h

+1 −0
Original line number Diff line number Diff line
@@ -99,6 +99,7 @@ struct dmtimer_platform_data { 
int omap_dm_timer_reserve_systimer(int id);

struct omap_dm_timer *omap_dm_timer_request(void);

struct omap_dm_timer *omap_dm_timer_request_specific(int timer_id);

struct omap_dm_timer *omap_dm_timer_request_by_cap(u32 cap);

int omap_dm_timer_free(struct omap_dm_timer *timer);

void omap_dm_timer_enable(struct omap_dm_timer *timer);

void omap_dm_timer_disable(struct omap_dm_timer *timer);

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