mfd: ab8500-sysctrl: Provide a platform specific pm_power_off() call-back

The kernel allows us to specify a function call-back which will be
invoked when a system power-off request has been received. Here we
provide one which is to be used when shutting down AB8500 based
platforms.

Signed-off-by: Lee Jones <lee.jones@linaro.org>

1 files changed, 22 insertions, 0 deletions

diff --git a/drivers/mfd/ab8500-sysctrl.c b/drivers/mfd/ab8500-sysctrl.c
index 8a33b2c7eead..888e066c715b 100644
--- a/drivers/mfd/ab8500-sysctrl.c
+++ b/drivers/mfd/ab8500-sysctrl.c
@@ -7,12 +7,29 @@
 #include <linux/err.h>
 #include <linux/module.h>
 #include <linux/platform_device.h>
+#include <linux/pm.h>
+#include <linux/signal.h>
 #include <linux/mfd/abx500.h>
 #include <linux/mfd/abx500/ab8500.h>
 #include <linux/mfd/abx500/ab8500-sysctrl.h>
 
 static struct device *sysctrl_dev;
 
+void ab8500_power_off(void)
+{
+        sigset_t old;
+        sigset_t all;
+
+        sigfillset(&all);
+
+        if (!sigprocmask(SIG_BLOCK, &all, &old)) {
+                (void)ab8500_sysctrl_set(AB8500_STW4500CTRL1,
+                                         AB8500_STW4500CTRL1_SWOFF |
+                                         AB8500_STW4500CTRL1_SWRESET4500N);
+                (void)sigprocmask(SIG_SETMASK, &old, NULL);
+        }
+}
+
 static inline bool valid_bank(u8 bank)
 {
         return ((bank == AB8500_SYS_CTRL1_BLOCK) ||
@@ -51,7 +68,12 @@ int ab8500_sysctrl_write(u16 reg, u8 mask, u8 value)
 
 static int ab8500_sysctrl_probe(struct platform_device *pdev)
 {
+        struct ab8500_platform_data *plat;
+
         sysctrl_dev = &pdev->dev;
+        plat = dev_get_platdata(pdev->dev.parent);
+        if (plat->pm_power_off)
+                pm_power_off = ab8500_power_off;
         return 0;
 }