ARM: OMAP2+: gpmc: Low power transition support

GPMC is hardware controller for external memory interfaces.
This patch adds suspend/resume support for GPMC driver.
It also preserves GPMC register configurations across device low-power states
in which GPMC hardware can be powered-off.
gpmc_suspend()/gpmc_resume() are called by default by core PM framework as part
of driver's runtime PM callbacks.

Signed-off-by: Philip Avinash <avinashphilip@ti.com>
Signed-off-by: Pekon Gupta <pekon@ti.com>
Signed-off-by: Tony Lindgren <tony@atomide.com>

1 files changed, 19 insertions, 2 deletions

diff --git a/arch/arm/mach-omap2/gpmc.c b/arch/arm/mach-omap2/gpmc.c
index bac18b3ebbfb..1c7969e965d7 100644
--- a/arch/arm/mach-omap2/gpmc.c
+++ b/arch/arm/mach-omap2/gpmc.c
@@ -1669,6 +1669,24 @@ static int gpmc_remove(struct platform_device *pdev)
         return 0;
 }
 
+#ifdef CONFIG_PM_SLEEP
+static int gpmc_suspend(struct device *dev)
+{
+        omap3_gpmc_save_context();
+        pm_runtime_put_sync(dev);
+        return 0;
+}
+
+static int gpmc_resume(struct device *dev)
+{
+        pm_runtime_get_sync(dev);
+        omap3_gpmc_restore_context();
+        return 0;
+}
+#endif
+
+static SIMPLE_DEV_PM_OPS(gpmc_pm_ops, gpmc_suspend, gpmc_resume);
+
 static struct platform_driver gpmc_driver = {
         .probe          = gpmc_probe,
         .remove         = gpmc_remove,
@@ -1676,6 +1694,7 @@ static struct platform_driver gpmc_driver = {
                 .name   = DEVICE_NAME,
                 .owner  = THIS_MODULE,
                 .of_match_table = of_match_ptr(gpmc_dt_ids),
+                .pm     = &gpmc_pm_ops,
         },
 };
 
@@ -1738,7 +1757,6 @@ static irqreturn_t gpmc_handle_irq(int irq, void *dev)
         return IRQ_HANDLED;
 }
 
-#ifdef CONFIG_ARCH_OMAP3
 static struct omap3_gpmc_regs gpmc_context;
 
 void omap3_gpmc_save_context(void)
@@ -1803,4 +1821,3 @@ void omap3_gpmc_restore_context(void)
                 }
         }
 }
-#endif /* CONFIG_ARCH_OMAP3 */