[ARM] pxa: Avoid fiddling with CKEN register on suspend

The PXA manuals indicate that when in standby or sleep modes, clocks to
peripherals are shut off by the processor itself.  Eg:

PXA270 standby: "In standby mode, all clocks are disabled except those
 for the power manager and the RTC."

PXA270 sleep: "In sleep mode, all clocks are disabled to the processor
 and to all peripherals except the RTC."

PXA255 sleep: "In Sleep Mode, all processor and peripheral clocks are
 disabled, except the RTC."

Therefore, it should be safe to leave the clock enable register alone
prior to entering low power modes for these SoCs.

Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>

diff --git a/arch/arm/mach-pxa/pxa25x.c b/arch/arm/mach-pxa/pxa25x.c
index 962cfbb5500ea6ed2a27547534190e5d0359fc17..73a5f068e167df7087cf6098302a17f815c7c0d0 100644 (file)
--- a/arch/arm/mach-pxa/pxa25x.c
+++ b/arch/arm/mach-pxa/pxa25x.c
@@ -216,8 +216,6 @@ static void pxa25x_cpu_pm_restore(unsigned long *sleep_save)
 
 static void pxa25x_cpu_pm_enter(suspend_state_t state)
 {
-       CKEN = 0;
-
        switch (state) {
        case PM_SUSPEND_MEM:
                /* set resume return address */

diff --git a/arch/arm/mach-pxa/pxa27x.c b/arch/arm/mach-pxa/pxa27x.c
index f33c9d7ff87e8db15b648a46ed12de5bc83ef36e..db0c4c6fea9ba06ae2bb91673e8004cfb645901c 100644 (file)
--- a/arch/arm/mach-pxa/pxa27x.c
+++ b/arch/arm/mach-pxa/pxa27x.c
@@ -265,12 +265,6 @@ void pxa27x_cpu_pm_enter(suspend_state_t state)
 {
        extern void pxa_cpu_standby(void);
 
-       if (state == PM_SUSPEND_STANDBY)
-               CKEN = (1 << CKEN_MEMC) | (1 << CKEN_OSTIMER) |
-                       (1 << CKEN_LCD) | (1 << CKEN_PWM0);
-       else
-               CKEN = (1 << CKEN_MEMC) | (1 << CKEN_OSTIMER);
-
        /* ensure voltage-change sequencer not initiated, which hangs */
        PCFR &= ~PCFR_FVC;