gpio: gpio-rcar: Support S2RAM

This patch adds an implementation that saves and restores the state of
GPIO configuration on suspend and resume.

Signed-off-by: Hien Dang <hien.dang.eb@renesas.com>
Signed-off-by: Takeshi Kihara <takeshi.kihara.df@renesas.com>
[Modify structure of the bank info to simplify a saving registers]
[Remove DEV_PM_OPS macro]
Signed-off-by: Yoshihiro Kaneko <ykaneko0929@gmail.com>
Tested-by: Nguyen Viet Dung <dung.nguyen.aj@renesas.com>
Reviewed-by: Simon Horman <horms+renesas@verge.net.au>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>

diff --git a/drivers/gpio/gpio-rcar.c b/drivers/gpio/gpio-rcar.c
index e76de57..e5b0dbe 100644 (file)
--- a/drivers/gpio/gpio-rcar.c
+++ b/drivers/gpio/gpio-rcar.c
@@ -31,6 +31,16 @@
 #include <linux/spinlock.h>
 #include <linux/slab.h>
 
+struct gpio_rcar_bank_info {
+       u32 iointsel;
+       u32 inoutsel;
+       u32 outdt;
+       u32 posneg;
+       u32 edglevel;
+       u32 bothedge;
+       u32 intmsk;
+};
+
 struct gpio_rcar_priv {
        void __iomem *base;
        spinlock_t lock;
@@ -41,6 +51,7 @@ struct gpio_rcar_priv {
        unsigned int irq_parent;
        bool has_both_edge_trigger;
        bool needs_clk;
+       struct gpio_rcar_bank_info bank_info;
 };
 
 #define IOINTSEL 0x00  /* General IO/Interrupt Switching Register */
@@ -531,11 +542,66 @@ static int gpio_rcar_remove(struct platform_device *pdev)
        return 0;
 }
 
+#ifdef CONFIG_PM_SLEEP
+static int gpio_rcar_suspend(struct device *dev)
+{
+       struct gpio_rcar_priv *p = dev_get_drvdata(dev);
+
+       p->bank_info.iointsel = gpio_rcar_read(p, IOINTSEL);
+       p->bank_info.inoutsel = gpio_rcar_read(p, INOUTSEL);
+       p->bank_info.outdt = gpio_rcar_read(p, OUTDT);
+       p->bank_info.intmsk = gpio_rcar_read(p, INTMSK);
+       p->bank_info.posneg = gpio_rcar_read(p, POSNEG);
+       p->bank_info.edglevel = gpio_rcar_read(p, EDGLEVEL);
+       if (p->has_both_edge_trigger)
+               p->bank_info.bothedge = gpio_rcar_read(p, BOTHEDGE);
+
+       return 0;
+}
+
+static int gpio_rcar_resume(struct device *dev)
+{
+       struct gpio_rcar_priv *p = dev_get_drvdata(dev);
+       unsigned int offset;
+       u32 mask;
+
+       for (offset = 0; offset < p->gpio_chip.ngpio; offset++) {
+               mask = BIT(offset);
+               /* I/O pin */
+               if (!(p->bank_info.iointsel & mask)) {
+                       if (p->bank_info.inoutsel & mask)
+                               gpio_rcar_direction_output(
+                                       &p->gpio_chip, offset,
+                                       !!(p->bank_info.outdt & mask));
+                       else
+                               gpio_rcar_direction_input(&p->gpio_chip,
+                                                         offset);
+               } else {
+                       /* Interrupt pin */
+                       gpio_rcar_config_interrupt_input_mode(
+                               p,
+                               offset,
+                               !(p->bank_info.posneg & mask),
+                               !(p->bank_info.edglevel & mask),
+                               !!(p->bank_info.bothedge & mask));
+
+                       if (p->bank_info.intmsk & mask)
+                               gpio_rcar_write(p, MSKCLR, mask);
+               }
+       }
+
+       return 0;
+}
+#endif /* CONFIG_PM_SLEEP*/
+
+static SIMPLE_DEV_PM_OPS(gpio_rcar_pm_ops, gpio_rcar_suspend, gpio_rcar_resume);
+
 static struct platform_driver gpio_rcar_device_driver = {
        .probe          = gpio_rcar_probe,
        .remove         = gpio_rcar_remove,
        .driver         = {
                .name   = "gpio_rcar",
+               .pm     = &gpio_rcar_pm_ops,
                .of_match_table = of_match_ptr(gpio_rcar_of_table),
        }
 };