[PATCH] ARM: 2781/2: PXA27x Standby mode take 2

Patch from Todd Poynor

Add support for PXA27x Standby mode, a low-power mode that retains CPU
and some peripheral state (the existing "sleep" mode is a power-power
mode that retains less state). Activated via:
echo -n standby > /sys/power/state
From: David Burrage and Todd Poynor

Signed-off-by: Todd Poynor <tpoynor@mvista.com>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>

1 files changed, 8 insertions, 1 deletions

diff --git a/arch/arm/mach-pxa/pxa27x.c b/arch/arm/mach-pxa/pxa27x.c
index 893964fb9659..9a791b07118d 100644
--- a/arch/arm/mach-pxa/pxa27x.c
+++ b/arch/arm/mach-pxa/pxa27x.c
@@ -126,6 +126,7 @@ int pxa_cpu_pm_prepare(suspend_state_t state)
 {
         switch (state) {
         case PM_SUSPEND_MEM:
+        case PM_SUSPEND_STANDBY:
                 return 0;
         default:
                 return -EINVAL;
@@ -138,7 +139,10 @@ void pxa_cpu_pm_enter(suspend_state_t state)
         extern void pxa_cpu_suspend(unsigned int);
         extern void pxa_cpu_resume(void);
 
-        CKEN = CKEN22_MEMC | CKEN9_OSTIMER;
+        if (state == PM_SUSPEND_STANDBY)
+                CKEN = CKEN22_MEMC | CKEN9_OSTIMER | CKEN16_LCD |CKEN0_PWM0;
+        else
+                CKEN = CKEN22_MEMC | CKEN9_OSTIMER;
 
         /* ensure voltage-change sequencer not initiated, which hangs */
         PCFR &= ~PCFR_FVC;
@@ -147,6 +151,9 @@ void pxa_cpu_pm_enter(suspend_state_t state)
         PEDR = 0xDF12FE1B;
 
         switch (state) {
+        case PM_SUSPEND_STANDBY:
+                pxa_cpu_standby();
+                break;
         case PM_SUSPEND_MEM:
                 /* set resume return address */
                 PSPR = virt_to_phys(pxa_cpu_resume);