On 23/01/2015 at 17:50:20 +0100, Sylvain Rochet wrote :

Hello Wenyou,


On Tue, Jan 20, 2015 at 04:17:00PM +0800, Wenyou Yang wrote:

quoted

diff --git a/arch/arm/mach-at91/pm.c b/arch/arm/mach-at91/pm.c
index 691e6db..a1010f0 100644
--- a/arch/arm/mach-at91/pm.c
+++ b/arch/arm/mach-at91/pm.c

quoted

@@ -145,62 +145,51 @@ extern void at91_slow_clock(void __iomem *pmc, void __iomem *ramc0,
 			    void __iomem *ramc1, int memctrl);
 extern u32 at91_slow_clock_sz;
 
+static void at91_pm_suspend(suspend_state_t state)
+{

      (...)

quoted

+	slow_clock(at91_pmc_base, at91_ramc_base[0],
+			at91_ramc_base[1], pm_data);
+}

quoted

-			if (slow_clock) {
-				slow_clock(at91_pmc_base, at91_ramc_base[0],
-					   at91_ramc_base[1],
-					   at91_pm_data.memctrl);

      (...)

quoted

+               at91_pm_suspend(state);

By doing that you removed the condition "if (slow_clock)".

But slow_clock can still be NULL, see commit d2e4679, there are multiple 
reasons which ends up with a NULL slow_clock.

I would fix that by not calling suspend_set_ops(&at91_pm_ops) when
slow_clock is NULL in patch 6 (quick and easy) or copying the whole
at91_pm_sram_init() in at91_pm_init() and handle failures from there.


-- 
Alexandre Belloni, Free Electrons
Embedded Linux, Kernel and Android engineering
http://free-electrons.com