ARM: mach-shmobile: Suspend-to-RAM support

This patch adds a simple Suspend-to-RAM implementation
for SH-Mobile ARM. The struct shmobile_suspend_ops are
kept global to allow cpu-specific code to override
the callbacks if needed.

Signed-off-by: Magnus Damm <damm@opensource.se>
Signed-off-by: Paul Mundt <lethal@linux-sh.org>

3 files changed, 51 insertions, 0 deletions

diff --git a/arch/arm/mach-shmobile/Makefile b/arch/arm/mach-shmobile/Makefile
index e2507f66f9d5..a3cad5360a71 100644
--- a/arch/arm/mach-shmobile/Makefile
+++ b/arch/arm/mach-shmobile/Makefile
@@ -30,6 +30,9 @@ obj-$(CONFIG_ARCH_SH7377)	+= entry-intc.o
 obj-$(CONFIG_ARCH_SH7372)	+= entry-intc.o
 obj-$(CONFIG_ARCH_SH73A0)	+= entry-gic.o
 
+# PM objects
+obj-$(CONFIG_SUSPEND)		+= suspend.o
+
 # Board objects
 obj-$(CONFIG_MACH_G3EVM)	+= board-g3evm.o
 obj-$(CONFIG_MACH_G4EVM)	+= board-g4evm.o
diff --git a/arch/arm/mach-shmobile/include/mach/common.h b/arch/arm/mach-shmobile/include/mach/common.h
index 013ac0ee8256..39b78bb80e09 100644
--- a/arch/arm/mach-shmobile/include/mach/common.h
+++ b/arch/arm/mach-shmobile/include/mach/common.h
@@ -8,6 +8,7 @@ struct clk;
 extern int clk_init(void);
 extern void shmobile_handle_irq_intc(struct pt_regs *);
 extern void shmobile_handle_irq_gic(struct pt_regs *);
+extern struct platform_suspend_ops shmobile_suspend_ops;
 
 extern void sh7367_init_irq(void);
 extern void sh7367_add_early_devices(void);
diff --git a/arch/arm/mach-shmobile/suspend.c b/arch/arm/mach-shmobile/suspend.c
new file mode 100644
index 000000000000..c1febe13f709
--- /dev/null
+++ b/arch/arm/mach-shmobile/suspend.c
@@ -0,0 +1,47 @@
+/*
+ * Suspend-to-RAM support code for SH-Mobile ARM
+ *
+ *  Copyright (C) 2011 Magnus Damm
+ *
+ * This file is subject to the terms and conditions of the GNU General Public
+ * License.  See the file "COPYING" in the main directory of this archive
+ * for more details.
+ */
+
+#include <linux/pm.h>
+#include <linux/suspend.h>
+#include <linux/module.h>
+#include <linux/err.h>
+#include <asm/system.h>
+#include <asm/io.h>
+
+static int shmobile_suspend_default_enter(suspend_state_t suspend_state)
+{
+	cpu_do_idle();
+	return 0;
+}
+
+static int shmobile_suspend_begin(suspend_state_t state)
+{
+	disable_hlt();
+	return 0;
+}
+
+static void shmobile_suspend_end(void)
+{
+	enable_hlt();
+}
+
+struct platform_suspend_ops shmobile_suspend_ops = {
+	.begin		= shmobile_suspend_begin,
+	.end		= shmobile_suspend_end,
+	.enter		= shmobile_suspend_default_enter,
+	.valid		= suspend_valid_only_mem,
+};
+
+static int __init shmobile_suspend_init(void)
+{
+	suspend_set_ops(&shmobile_suspend_ops);
+	return 0;
+}
+late_initcall(shmobile_suspend_init);