openkylin
/
platform_kernel-5.15
mirror of https://gitee.com/openkylin/platform_kernel-5.15.git
9
0
Fork 0
Code Issues Projects Releases Wiki Activity

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 <jon-hunter@ti.com>
Acked-by: Tony Lindgren <tony@atomide.com>
Signed-off-by: Benoit Cousson <benoit.cousson@linaro.org>
This commit is contained in:
Jon Hunter 2013-03-19 12:38:17 -05:00 committed by Benoit Cousson
parent 385c4c7b7c
commit 8fc7fcb593
2 changed files with 96 additions and 76 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

171
arch/arm/plat-omap/dmtimer.c
View File

@ -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);
@ -259,47 +299,26 @@ 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;
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;
return _omap_dm_timer_request(REQUEST_BY_CAP, &cap);
}
EXPORT_SYMBOL_GPL(omap_dm_timer_request_by_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;
return _omap_dm_timer_request(REQUEST_BY_NODE, np);
}
EXPORT_SYMBOL_GPL(omap_dm_timer_request_by_node);
int omap_dm_timer_free(struct omap_dm_timer *timer)
{
if (unlikely(!timer))

1
arch/arm/plat-omap/include/plat/dmtimer.h
View File

@ -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);