[PATCH 3/5] ARM: OMAP: Add function to request timer by node
Jon Hunter
jon-hunter at ti.com
Wed Mar 20 04:38:17 EST 2013
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 <jon-hunter at ti.com>
---
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 725d972..05efb37 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 a3fbc48..fb92abb 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);
--
1.7.10.4
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