[ARM] 5264/2: [AT91] Suspend-to-RAM disables main oscillator

[linux-2.6-omap-h63xx.git] / arch / arm / mach-at91 / Kconfig

diff --git a/arch/arm/mach-at91/Kconfig b/arch/arm/mach-at91/Kconfig
index 68537e37387f7f8460b688cfc1d681df7e253759..5aafb2e2ca7a538335957df1508009f5784f0230 100644 (file)
--- a/arch/arm/mach-at91/Kconfig
+++ b/arch/arm/mach-at91/Kconfig
@@ -323,6 +323,19 @@ config AT91_PROGRAMMABLE_CLOCKS
          Select this if you need to program one or more of the PCK0..PCK3
          programmable clock outputs.
 
+config AT91_SLOW_CLOCK
+       bool "Suspend-to-RAM disables main oscillator"
+       depends on SUSPEND
+       help
+         Select this if you want Suspend-to-RAM to save the most power
+         possible (without powering off the CPU) by disabling the PLLs
+         and main oscillator so that only the 32 KiHz clock is available.
+
+         When only that slow-clock is available, some peripherals lose
+         functionality.  Many can't issue wakeup events unless faster
+         clocks are available.  Some lose their operating state and
+         need to be completely re-initialized.
+
 config AT91_TIMER_HZ
        int "Kernel HZ (jiffies per second)"
        range 32 1024