OMAP3: Fixed crash bug with serial + suspend

It was possible for an unhandled interrupt to occur if there was incoming
serial traffic during wakeup from suspend. This was caused by the code
in arch-arm/mach-omap2/serial.c keeping interrupt enabled all the time,
but not acking its interrupts. Applies on top of PM branch.

Use the PM begin/end hooks to ensure that the "serial idle" interrupts
are disabled during the suspend path.  Also, since begin/end hooks are
now used, use the suspend_state that is passed in the begin hook instead
of the enter hook as per the platform_suspend_ops docs.

Signed-off-by: Tero Kristo <tero.kristo@nokia.com>
Signed-off-by: Kevin Hilman <khilman@deeprootsystems.com>
This commit is contained in:
Tero Kristo 2009-03-05 16:32:23 +02:00 committed by Kevin Hilman
parent 4789998a30
commit 2466211e5d
3 changed files with 36 additions and 2 deletions

View File

@ -296,6 +296,8 @@ out:
}
#ifdef CONFIG_SUSPEND
static suspend_state_t suspend_state;
static int omap3_pm_prepare(void)
{
disable_hlt();
@ -342,11 +344,11 @@ restore:
return ret;
}
static int omap3_pm_enter(suspend_state_t state)
static int omap3_pm_enter(suspend_state_t unused)
{
int ret = 0;
switch (state) {
switch (suspend_state) {
case PM_SUSPEND_STANDBY:
case PM_SUSPEND_MEM:
ret = omap3_pm_suspend();
@ -363,7 +365,24 @@ static void omap3_pm_finish(void)
enable_hlt();
}
/* Hooks to enable / disable UART interrupts during suspend */
static int omap3_pm_begin(suspend_state_t state)
{
suspend_state = state;
omap_uart_enable_irqs(0);
return 0;
}
static void omap3_pm_end(void)
{
suspend_state = PM_SUSPEND_ON;
omap_uart_enable_irqs(1);
return;
}
static struct platform_suspend_ops omap_pm_ops = {
.begin = omap3_pm_begin,
.end = omap3_pm_end,
.prepare = omap3_pm_prepare,
.enter = omap3_pm_enter,
.finish = omap3_pm_finish,

View File

@ -435,6 +435,20 @@ static void omap_uart_idle_init(struct omap_uart_state *uart)
WARN_ON(ret);
}
void omap_uart_enable_irqs(int enable)
{
int ret;
struct omap_uart_state *uart;
list_for_each_entry(uart, &uart_list, node) {
if (enable)
ret = request_irq(uart->p->irq, omap_uart_interrupt,
IRQF_SHARED, "serial idle", (void *)uart);
else
free_irq(uart->p->irq, (void *)uart);
}
}
static ssize_t sleep_timeout_show(struct kobject *kobj,
struct kobj_attribute *attr,
char *buf)

View File

@ -59,6 +59,7 @@ extern void omap_uart_check_wakeup(void);
extern void omap_uart_prepare_suspend(void);
extern void omap_uart_prepare_idle(int num);
extern void omap_uart_resume_idle(int num);
extern void omap_uart_enable_irqs(int enable);
#endif
#endif