OMAP2+: disable idle early in the suspend sequence
Some bad interaction between the idle and the suspend paths has been
identified: the idle code is called during the suspend enter and exit
sequences. This could cause corruption or lock-up of resources.
The solution is to move the calls to disable_hlt at the very beginning
of the suspend sequence (ex. in omap3_pm_begin instead of
omap3_pm_prepare), and the call to enable_hlt at the very end of
the suspend sequence (ex. in omap3_pm_end instead of omap3_pm_finish).
Tested with RET and OFF on Beagle and OMAP3EVM.
Signed-off-by: Jean Pihet <j-pihet@ti.com>
Cc: Kevin Hilman <khilman@deeprootsystems.com>
Signed-off-by: Kevin Hilman <khilman@deeprootsystems.com>
diff --git a/arch/arm/mach-omap2/pm24xx.c b/arch/arm/mach-omap2/pm24xx.c
index aaeea49..aea7ced 100644
--- a/arch/arm/mach-omap2/pm24xx.c
+++ b/arch/arm/mach-omap2/pm24xx.c
@@ -301,14 +301,8 @@
static int omap2_pm_begin(suspend_state_t state)
{
- suspend_state = state;
- return 0;
-}
-
-static int omap2_pm_prepare(void)
-{
- /* We cannot sleep in idle until we have resumed */
disable_hlt();
+ suspend_state = state;
return 0;
}
@@ -349,21 +343,15 @@
return ret;
}
-static void omap2_pm_finish(void)
-{
- enable_hlt();
-}
-
static void omap2_pm_end(void)
{
suspend_state = PM_SUSPEND_ON;
+ enable_hlt();
}
static struct platform_suspend_ops omap_pm_ops = {
.begin = omap2_pm_begin,
- .prepare = omap2_pm_prepare,
.enter = omap2_pm_enter,
- .finish = omap2_pm_finish,
.end = omap2_pm_end,
.valid = suspend_valid_only_mem,
};
diff --git a/arch/arm/mach-omap2/pm34xx.c b/arch/arm/mach-omap2/pm34xx.c
index 648b8c5..5bf344a 100644
--- a/arch/arm/mach-omap2/pm34xx.c
+++ b/arch/arm/mach-omap2/pm34xx.c
@@ -529,12 +529,6 @@
}
#ifdef CONFIG_SUSPEND
-static int omap3_pm_prepare(void)
-{
- disable_hlt();
- return 0;
-}
-
static int omap3_pm_suspend(void)
{
struct power_state *pwrst;
@@ -597,14 +591,10 @@
return ret;
}
-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)
{
+ disable_hlt();
suspend_state = state;
omap_uart_enable_irqs(0);
return 0;
@@ -614,15 +604,14 @@
{
suspend_state = PM_SUSPEND_ON;
omap_uart_enable_irqs(1);
+ enable_hlt();
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,
.valid = suspend_valid_only_mem,
};
#endif /* CONFIG_SUSPEND */
diff --git a/arch/arm/mach-omap2/pm44xx.c b/arch/arm/mach-omap2/pm44xx.c
index 54544b4..6aff996 100644
--- a/arch/arm/mach-omap2/pm44xx.c
+++ b/arch/arm/mach-omap2/pm44xx.c
@@ -31,12 +31,6 @@
static LIST_HEAD(pwrst_list);
#ifdef CONFIG_SUSPEND
-static int omap4_pm_prepare(void)
-{
- disable_hlt();
- return 0;
-}
-
static int omap4_pm_suspend(void)
{
do_wfi();
@@ -59,28 +53,22 @@
return ret;
}
-static void omap4_pm_finish(void)
-{
- enable_hlt();
- return;
-}
-
static int omap4_pm_begin(suspend_state_t state)
{
+ disable_hlt();
return 0;
}
static void omap4_pm_end(void)
{
+ enable_hlt();
return;
}
static struct platform_suspend_ops omap_pm_ops = {
.begin = omap4_pm_begin,
.end = omap4_pm_end,
- .prepare = omap4_pm_prepare,
.enter = omap4_pm_enter,
- .finish = omap4_pm_finish,
.valid = suspend_valid_only_mem,
};
#endif /* CONFIG_SUSPEND */