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>

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;
 }
 

include/linux/mfd/abx500/ab8500.h

@@ -274,6 +274,7 @@ struct ab8500_codec_platform_data;
 /**
  * struct ab8500_platform_data - AB8500 platform data
  * @irq_base: start of AB8500 IRQs, AB8500_NR_IRQS will be used
+ * @pm_power_off: Should machine pm power off hook be registered or not
  * @init: board-specific initialization after detection of ab8500
  * @num_regulator_reg_init: number of regulator init registers
  * @regulator_reg_init: regulator init registers
@@ -282,6 +283,7 @@ struct ab8500_codec_platform_data;
  */
 struct ab8500_platform_data {
 	int irq_base;
+	bool pm_power_off;
 	void (*init) (struct ab8500 *);
 	int num_regulator_reg_init;
 	struct ab8500_regulator_reg_init *regulator_reg_init;