ux500: add system shutdown support

This implementation is derived from Linus Walleij's similar
support for mach-u300 platforms. We write to the Ab8500 reset
register to shut off the board.

An ideal way is to request the PRCMU for a system reset,
which would be available only later on!

ST-Ericsson Change ID: ER254471

Signed-off-by: Sundar R Iyer <sundar.iyer@stericsson.com>
Signed-off-by: Mian Yousaf Kaukab <mian.yousaf.kaukab@stericsson.com>
Change-Id: I1571f5506aadac0ad55fa6db61246587de57fbcb
Reviewed-on: http://gerrit.lud.stericsson.com/gerrit/2360
Reviewed-by: Jonas ABERG <jonas.aberg@stericsson.com>

1 files changed, 26 insertions, 0 deletions

diff --git a/arch/arm/mach-ux500/pm.c b/arch/arm/mach-ux500/pm.c
index 509c2c59c02..96f040a8eda 100755
--- a/arch/arm/mach-ux500/pm.c
+++ b/arch/arm/mach-ux500/pm.c
@@ -32,6 +32,29 @@ static int u8500_pm_prepare(void)
 	return 0;
 }
 
+/* poweroff support */
+#include <linux/signal.h>
+#include <mach/ab8500.h>
+/*
+ * This function is used from pm.h to shut down the u8500 system by
+ * turning off the ab8500
+ */
+void u8500_pm_poweroff(void)
+{
+	sigset_t old, all;
+	int val;
+
+	sigfillset(&all);
+	if (!sigprocmask(SIG_BLOCK, &all, &old)) {
+		val = ab8500_read(AB8500_SYS_CTRL1_BLOCK, AB8500_CTRL1_REG);
+		val |= 0x1;
+		ab8500_write(AB8500_SYS_CTRL1_BLOCK, AB8500_CTRL1_REG, val);
+		(void) sigprocmask(SIG_SETMASK, &old, NULL);
+	}
+	return;
+}
+
+
 /* GPIO context */
 static struct ux500_gpio_regs gpio_context[UX500_NR_GPIO_BANKS];
 
@@ -827,6 +850,9 @@ static int __init u8500_pm_init(void)
 		return -ENOMEM;
 	}
 
+	/* register the global power off hook */
+	pm_power_off = u8500_pm_poweroff;
+
 	suspend_set_ops(&u8500_pm_ops);
 
 	return 0;