From 373fe0bdf9911c4362942162a2b4d20e6f74da5b Mon Sep 17 00:00:00 2001 From: Jon Hunter Date: Thu, 6 Sep 2012 15:28:00 -0500 Subject: [PATCH] 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: Jon Hunter --- arch/arm/plat-omap/dmtimer.c | 52 +++++++++++++++++++++++ arch/arm/plat-omap/include/plat/dmtimer.h | 1 + 2 files changed, 53 insertions(+) diff --git a/arch/arm/plat-omap/dmtimer.c b/arch/arm/plat-omap/dmtimer.c index 938b50a33439..2574b86ad2dc 100644 --- a/arch/arm/plat-omap/dmtimer.c +++ b/arch/arm/plat-omap/dmtimer.c @@ -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)) diff --git a/arch/arm/plat-omap/include/plat/dmtimer.h b/arch/arm/plat-omap/include/plat/dmtimer.h index 85868e98c11c..348f855d3dab 100644 --- a/arch/arm/plat-omap/include/plat/dmtimer.h +++ b/arch/arm/plat-omap/include/plat/dmtimer.h @@ -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); -- 2.20.1