[PATCH v15 11/12] OMAP: dmtimer: extend spinlock to exported APIs
Tarun Kanti DebBarma
tarun.kanti at ti.com
Thu Sep 8 17:08:17 EDT 2011
Since the exported APIs can be called from interrupt context
extend spinlock protection to some more relevant APIs to avoid
race condition.
Signed-off-by: Tarun Kanti DebBarma <tarun.kanti at ti.com>
Reviewed-by: Santosh Shilimkar <santosh.shilimkar at ti.com>
---
arch/arm/plat-omap/dmtimer.c | 34 +++++++++++++++++++++++++++++++---
1 files changed, 31 insertions(+), 3 deletions(-)
diff --git a/arch/arm/plat-omap/dmtimer.c b/arch/arm/plat-omap/dmtimer.c
index 15fe01a..8891f80 100644
--- a/arch/arm/plat-omap/dmtimer.c
+++ b/arch/arm/plat-omap/dmtimer.c
@@ -174,7 +174,6 @@ struct omap_dm_timer *omap_dm_timer_request(void)
timer->reserved = 1;
break;
}
- spin_unlock_irqrestore(&dm_timer_lock, flags);
if (timer) {
ret = omap_dm_timer_prepare(timer);
@@ -183,6 +182,7 @@ struct omap_dm_timer *omap_dm_timer_request(void)
timer = NULL;
}
}
+ spin_unlock_irqrestore(&dm_timer_lock, flags);
if (!timer)
pr_debug("%s: timer request failed!\n", __func__);
@@ -205,7 +205,6 @@ struct omap_dm_timer *omap_dm_timer_request_specific(int id)
break;
}
}
- spin_unlock_irqrestore(&dm_timer_lock, flags);
if (timer) {
ret = omap_dm_timer_prepare(timer);
@@ -214,6 +213,7 @@ struct omap_dm_timer *omap_dm_timer_request_specific(int id)
timer = NULL;
}
}
+ spin_unlock_irqrestore(&dm_timer_lock, flags);
if (!timer)
pr_debug("%s: timer%d request failed!\n", __func__, id);
@@ -317,9 +317,11 @@ EXPORT_SYMBOL_GPL(omap_dm_timer_trigger);
void omap_dm_timer_start(struct omap_dm_timer *timer)
{
u32 l;
+ unsigned long flags;
omap_dm_timer_enable(timer);
+ spin_lock_irqsave(&dm_timer_lock, flags);
if (timer->loses_context) {
u32 ctx_loss_cnt_after =
timer->get_context_loss_count(&timer->pdev->dev);
@@ -335,15 +337,17 @@ void omap_dm_timer_start(struct omap_dm_timer *timer)
/* Save the context */
timer->context.tclr = l;
+ spin_unlock_irqrestore(&dm_timer_lock, flags);
}
EXPORT_SYMBOL_GPL(omap_dm_timer_start);
void omap_dm_timer_stop(struct omap_dm_timer *timer)
{
- unsigned long rate = 0;
+ unsigned long rate = 0, flags;
struct dmtimer_platform_data *pdata = timer->pdev->dev.platform_data;
bool is_omap2 = true;
+ spin_lock_irqsave(&dm_timer_lock, flags);
if (pdata->needs_manual_reset)
is_omap2 = false;
else
@@ -367,6 +371,7 @@ void omap_dm_timer_stop(struct omap_dm_timer *timer)
omap_dm_timer_read_reg(timer, OMAP_TIMER_CTRL_REG);
timer->context.tisr =
omap_dm_timer_read_reg(timer, OMAP_TIMER_STAT_REG);
+ spin_unlock_irqrestore(&dm_timer_lock, flags);
omap_dm_timer_disable(timer);
}
EXPORT_SYMBOL_GPL(omap_dm_timer_stop);
@@ -389,8 +394,10 @@ void omap_dm_timer_set_load(struct omap_dm_timer *timer, int autoreload,
unsigned int load)
{
u32 l;
+ unsigned long flags;
omap_dm_timer_enable(timer);
+ spin_lock_irqsave(&dm_timer_lock, flags);
l = omap_dm_timer_read_reg(timer, OMAP_TIMER_CTRL_REG);
if (autoreload)
l |= OMAP_TIMER_CTRL_AR;
@@ -403,6 +410,7 @@ void omap_dm_timer_set_load(struct omap_dm_timer *timer, int autoreload,
/* Save the context */
timer->context.tclr = l;
timer->context.tldr = load;
+ spin_unlock_irqrestore(&dm_timer_lock, flags);
omap_dm_timer_disable(timer);
}
EXPORT_SYMBOL_GPL(omap_dm_timer_set_load);
@@ -412,9 +420,11 @@ void omap_dm_timer_set_load_start(struct omap_dm_timer *timer, int autoreload,
unsigned int load)
{
u32 l;
+ unsigned long flags;
omap_dm_timer_enable(timer);
+ spin_lock_irqsave(&dm_timer_lock, flags);
if (timer->loses_context) {
u32 ctx_loss_cnt_after =
timer->get_context_loss_count(&timer->pdev->dev);
@@ -438,6 +448,7 @@ void omap_dm_timer_set_load_start(struct omap_dm_timer *timer, int autoreload,
timer->context.tclr = l;
timer->context.tldr = load;
timer->context.tcrr = load;
+ spin_unlock_irqrestore(&dm_timer_lock, flags);
}
EXPORT_SYMBOL_GPL(omap_dm_timer_set_load_start);
@@ -445,8 +456,10 @@ void omap_dm_timer_set_match(struct omap_dm_timer *timer, int enable,
unsigned int match)
{
u32 l;
+ unsigned long flags;
omap_dm_timer_enable(timer);
+ spin_lock_irqsave(&dm_timer_lock, flags);
l = omap_dm_timer_read_reg(timer, OMAP_TIMER_CTRL_REG);
if (enable)
l |= OMAP_TIMER_CTRL_CE;
@@ -458,6 +471,7 @@ void omap_dm_timer_set_match(struct omap_dm_timer *timer, int enable,
/* Save the context */
timer->context.tclr = l;
timer->context.tmar = match;
+ spin_unlock_irqrestore(&dm_timer_lock, flags);
omap_dm_timer_disable(timer);
}
EXPORT_SYMBOL_GPL(omap_dm_timer_set_match);
@@ -466,8 +480,10 @@ void omap_dm_timer_set_pwm(struct omap_dm_timer *timer, int def_on,
int toggle, int trigger)
{
u32 l;
+ unsigned long flags;
omap_dm_timer_enable(timer);
+ spin_lock_irqsave(&dm_timer_lock, flags);
l = omap_dm_timer_read_reg(timer, OMAP_TIMER_CTRL_REG);
l &= ~(OMAP_TIMER_CTRL_GPOCFG | OMAP_TIMER_CTRL_SCPWM |
OMAP_TIMER_CTRL_PT | (0x03 << 10));
@@ -480,6 +496,7 @@ void omap_dm_timer_set_pwm(struct omap_dm_timer *timer, int def_on,
/* Save the context */
timer->context.tclr = l;
+ spin_unlock_irqrestore(&dm_timer_lock, flags);
omap_dm_timer_disable(timer);
}
EXPORT_SYMBOL_GPL(omap_dm_timer_set_pwm);
@@ -487,8 +504,10 @@ EXPORT_SYMBOL_GPL(omap_dm_timer_set_pwm);
void omap_dm_timer_set_prescaler(struct omap_dm_timer *timer, int prescaler)
{
u32 l;
+ unsigned long flags;
omap_dm_timer_enable(timer);
+ spin_lock_irqsave(&dm_timer_lock, flags);
l = omap_dm_timer_read_reg(timer, OMAP_TIMER_CTRL_REG);
l &= ~(OMAP_TIMER_CTRL_PRE | (0x07 << 2));
if (prescaler >= 0x00 && prescaler <= 0x07) {
@@ -499,6 +518,7 @@ void omap_dm_timer_set_prescaler(struct omap_dm_timer *timer, int prescaler)
/* Save the context */
timer->context.tclr = l;
+ spin_unlock_irqrestore(&dm_timer_lock, flags);
omap_dm_timer_disable(timer);
}
EXPORT_SYMBOL_GPL(omap_dm_timer_set_prescaler);
@@ -506,13 +526,17 @@ EXPORT_SYMBOL_GPL(omap_dm_timer_set_prescaler);
void omap_dm_timer_set_int_enable(struct omap_dm_timer *timer,
unsigned int value)
{
+ unsigned long flags;
+
omap_dm_timer_enable(timer);
+ spin_lock_irqsave(&dm_timer_lock, flags);
__omap_dm_timer_int_enable(timer->io_base, value,
timer->intr_offset, timer->func_offset);
/* Save the context */
timer->context.tier = value;
timer->context.twer = value;
+ spin_unlock_irqrestore(&dm_timer_lock, flags);
omap_dm_timer_disable(timer);
}
EXPORT_SYMBOL_GPL(omap_dm_timer_set_int_enable);
@@ -570,16 +594,20 @@ EXPORT_SYMBOL_GPL(omap_dm_timer_write_counter);
int omap_dm_timers_active(void)
{
struct omap_dm_timer *timer;
+ unsigned long flags;
+ spin_lock_irqsave(&dm_timer_lock, flags);
list_for_each_entry(timer, &omap_timer_list, node) {
if (!timer->reserved)
continue;
if (omap_dm_timer_read_reg(timer, OMAP_TIMER_CTRL_REG) &
OMAP_TIMER_CTRL_ST) {
+ spin_unlock_irqrestore(&dm_timer_lock, flags);
return 1;
}
}
+ spin_unlock_irqrestore(&dm_timer_lock, flags);
return 0;
}
EXPORT_SYMBOL_GPL(omap_dm_timers_active);
--
1.7.0.4
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