From: Tero Kristo <tero.kristo@xxxxxxxxx>
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@xxxxxxxxx>
Signed-off-by: Kevin Hilman <khilman@xxxxxxxxxxxxxxxxxxx>
---
arch/arm/mach-omap2/pm34xx.c | 23 +++++++++++++++++++++--
arch/arm/mach-omap2/serial.c | 14 ++++++++++++++
arch/arm/plat-omap/include/mach/serial.h | 1 +
3 files changed, 36 insertions(+), 2 deletions(-)
diff --git a/arch/arm/mach-omap2/pm34xx.c b/arch/arm/mach-omap2/pm34xx.c
index 528f725..b07efb2 100644
--- a/arch/arm/mach-omap2/pm34xx.c
+++ b/arch/arm/mach-omap2/pm34xx.c
@@ -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,
diff --git a/arch/arm/mach-omap2/serial.c b/arch/arm/mach-omap2/serial.c
index c82ec95..5352d05 100644
--- a/arch/arm/mach-omap2/serial.c
+++ b/arch/arm/mach-omap2/serial.c
@@ -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)
diff --git a/arch/arm/plat-omap/include/mach/serial.h b/arch/arm/plat-omap/include/mach/serial.h
index 13abd02..def0529 100644
--- a/arch/arm/plat-omap/include/mach/serial.h
+++ b/arch/arm/plat-omap/include/mach/serial.h
@@ -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
--
1.6.3.2
--
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