gpio/omap: handle save/restore context in GPIO driver

Modify omap_gpio_prepare_for_idle() & omap_gpio_resume_after_idle() functions
to handle save context & restore context respectively in the OMAP GPIO driver
itself instead of calling these functions from pm specific files.
For this, in gpio_prepare_for_idle(), call *_get_context_loss_count() and in
gpio_resume_after_idle() call it again. If the count is different, do restore
context.

Signed-off-by: Charulatha V <charu@ti.com>
Signed-off-by: Tarun Kanti DebBarma <tarun.kanti@ti.com>
Reviewed-by: Santosh Shilimkar <santosh.shilimkar@ti.com>
Acked-by: Tony Lindgren <tony@atomide.com>
Reviewed-by: Kevin Hilman <khilman@ti.com>
Signed-off-by: Kevin Hilman <khilman@ti.com>
diff --git a/arch/arm/mach-omap2/gpio.c b/arch/arm/mach-omap2/gpio.c
index 076be34..f84db8f 100644
--- a/arch/arm/mach-omap2/gpio.c
+++ b/arch/arm/mach-omap2/gpio.c
@@ -23,6 +23,7 @@
 
 #include <plat/omap_hwmod.h>
 #include <plat/omap_device.h>
+#include <plat/omap-pm.h>
 
 #include "powerdomain.h"
 
@@ -55,7 +56,7 @@
 	pdata->bank_width = dev_attr->bank_width;
 	pdata->dbck_flag = dev_attr->dbck_flag;
 	pdata->virtual_irq_start = IH_GPIO_BASE + 32 * (id - 1);
-
+	pdata->get_context_loss_count = omap_pm_get_dev_context_loss_count;
 	pdata->regs = kzalloc(sizeof(struct omap_gpio_reg_offs), GFP_KERNEL);
 	if (!pdata) {
 		pr_err("gpio%d: Memory allocation failed\n", id);