From 8fc7fcb593ac3c5730c8391c2d7db5b87e2d0bf2 Mon Sep 17 00:00:00 2001 From: Jon Hunter Date: Tue, 19 Mar 2013 12:38:17 -0500 Subject: [PATCH] ARM: OMAP: Add function to request timer by node Add a function so that OMAP dmtimers can be requested by device-tree node. This allows for devices, such as the internal DSP, or drivers, such as PWM, to reference a specific dmtimer node via the device-tree. Given that there are several APIs available for requesting dmtimers (by ID, by capability or by node) consolidate the code for all these functions into a single helper function that can be used by these request functions. Signed-off-by: Jon Hunter Acked-by: Tony Lindgren Signed-off-by: Benoit Cousson --- arch/arm/plat-omap/dmtimer.c | 167 ++++++++++++---------- arch/arm/plat-omap/include/plat/dmtimer.h | 1 + 2 files changed, 94 insertions(+), 74 deletions(-) diff --git a/arch/arm/plat-omap/dmtimer.c b/arch/arm/plat-omap/dmtimer.c index 725d9720dd2b..05efb370a2bd 100644 --- a/arch/arm/plat-omap/dmtimer.c +++ b/arch/arm/plat-omap/dmtimer.c @@ -52,6 +52,13 @@ static u32 omap_reserved_systimers; static LIST_HEAD(omap_timer_list); static DEFINE_SPINLOCK(dm_timer_lock); +enum { + REQUEST_ANY = 0, + REQUEST_BY_ID, + REQUEST_BY_CAP, + REQUEST_BY_NODE, +}; + /** * omap_dm_timer_read_reg - read timer registers in posted and non-posted mode * @timer: timer pointer over which read operation to perform @@ -178,29 +185,82 @@ int omap_dm_timer_reserve_systimer(int id) return 0; } -struct omap_dm_timer *omap_dm_timer_request(void) +static struct omap_dm_timer *_omap_dm_timer_request(int req_type, void *data) { struct omap_dm_timer *timer = NULL, *t; + struct device_node *np = NULL; unsigned long flags; - int ret = 0; + u32 cap = 0; + int id = 0; + + switch (req_type) { + case REQUEST_BY_ID: + id = *(int *)data; + break; + case REQUEST_BY_CAP: + cap = *(u32 *)data; + break; + case REQUEST_BY_NODE: + np = (struct device_node *)data; + break; + default: + /* REQUEST_ANY */ + break; + } spin_lock_irqsave(&dm_timer_lock, flags); list_for_each_entry(t, &omap_timer_list, node) { if (t->reserved) continue; - timer = t; - timer->reserved = 1; - break; + switch (req_type) { + case REQUEST_BY_ID: + if (id == t->pdev->id) { + timer = t; + timer->reserved = 1; + goto found; + } + break; + case REQUEST_BY_CAP: + if (cap == (t->capability & 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) + goto found; + } + break; + case REQUEST_BY_NODE: + if (np == t->pdev->dev.of_node) { + timer = t; + timer->reserved = 1; + goto found; + } + break; + default: + /* REQUEST_ANY */ + timer = t; + timer->reserved = 1; + goto found; + } } +found: spin_unlock_irqrestore(&dm_timer_lock, flags); - if (timer) { - ret = omap_dm_timer_prepare(timer); - if (ret) { - timer->reserved = 0; - timer = NULL; - } + if (timer && omap_dm_timer_prepare(timer)) { + timer->reserved = 0; + timer = NULL; } if (!timer) @@ -208,43 +268,23 @@ struct omap_dm_timer *omap_dm_timer_request(void) return timer; } + +struct omap_dm_timer *omap_dm_timer_request(void) +{ + return _omap_dm_timer_request(REQUEST_ANY, NULL); +} EXPORT_SYMBOL_GPL(omap_dm_timer_request); struct omap_dm_timer *omap_dm_timer_request_specific(int id) { - struct omap_dm_timer *timer = NULL, *t; - unsigned long flags; - int ret = 0; - /* Requesting timer by ID is not supported when device tree is used */ if (of_have_populated_dt()) { - pr_warn("%s: Please use omap_dm_timer_request_by_cap()\n", + pr_warn("%s: Please use omap_dm_timer_request_by_cap/node()\n", __func__); return NULL; } - spin_lock_irqsave(&dm_timer_lock, flags); - list_for_each_entry(t, &omap_timer_list, node) { - if (t->pdev->id == id && !t->reserved) { - timer = t; - timer->reserved = 1; - break; - } - } - spin_unlock_irqrestore(&dm_timer_lock, flags); - - if (timer) { - ret = omap_dm_timer_prepare(timer); - if (ret) { - timer->reserved = 0; - timer = NULL; - } - } - - if (!timer) - pr_debug("%s: timer%d request failed!\n", __func__, id); - - return timer; + return _omap_dm_timer_request(REQUEST_BY_ID, &id); } EXPORT_SYMBOL_GPL(omap_dm_timer_request_specific); @@ -259,46 +299,25 @@ EXPORT_SYMBOL_GPL(omap_dm_timer_request_specific); */ struct omap_dm_timer *omap_dm_timer_request_by_cap(u32 cap) { - struct omap_dm_timer *timer = NULL, *t; - unsigned long flags; + return _omap_dm_timer_request(REQUEST_BY_CAP, &cap); +} +EXPORT_SYMBOL_GPL(omap_dm_timer_request_by_cap); - if (!cap) +/** + * omap_dm_timer_request_by_node - Request a timer by device-tree node + * @np: Pointer to device-tree timer node + * + * Request a timer based upon a device node pointer. Returns pointer to + * timer handle on success and a NULL pointer on failure. + */ +struct omap_dm_timer *omap_dm_timer_request_by_node(struct device_node *np) +{ + if (!np) 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; + return _omap_dm_timer_request(REQUEST_BY_NODE, np); } -EXPORT_SYMBOL_GPL(omap_dm_timer_request_by_cap); +EXPORT_SYMBOL_GPL(omap_dm_timer_request_by_node); int omap_dm_timer_free(struct omap_dm_timer *timer) { diff --git a/arch/arm/plat-omap/include/plat/dmtimer.h b/arch/arm/plat-omap/include/plat/dmtimer.h index a3fbc48c332e..fb92abb91628 100644 --- a/arch/arm/plat-omap/include/plat/dmtimer.h +++ b/arch/arm/plat-omap/include/plat/dmtimer.h @@ -128,6 +128,7 @@ 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); +struct omap_dm_timer *omap_dm_timer_request_by_node(struct device_node *np); 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); -- 2.39.5