This patch enables suspend and resume mode for the power management, and
it is based on Josef Ahmad's previous work.
Reviewed-by: Hock Leong Kweh <hock.leong.kweh@xxxxxxxxx>
Reviewed-by: Shevchenko, Andriy <andriy.shevchenko@xxxxxxxxx>
Signed-off-by: Weike Chen <alvin.chen@xxxxxxxxx>
---
drivers/gpio/gpio-dwapb.c | 67 +++++++++++++++++++++++++++++++++++++++++++++
1 file changed, 67 insertions(+)
diff --git a/drivers/gpio/gpio-dwapb.c b/drivers/gpio/gpio-dwapb.c
index e0ab988..1055cb3 100644
--- a/drivers/gpio/gpio-dwapb.c
+++ b/drivers/gpio/gpio-dwapb.c
@@ -560,10 +560,77 @@ static const struct of_device_id dwapb_of_match[] = {
};
MODULE_DEVICE_TABLE(of, dwapb_of_match);
+#if defined CONFIG_PM_SLEEP
+/* Store GPIO context across system-wide suspend/resume transitions */
+static struct gpio_saved_regs {
+ unsigned long data;
+ unsigned long dir;
+ unsigned long int_en;
+ unsigned long int_mask;
+ unsigned long int_type;
+ unsigned long int_pol;
+ unsigned long int_deb;
+} saved_regs;
+
+static int dwapb_gpio_suspend(struct device *dev)
+{
+ struct platform_device *pdev = to_platform_device(dev);
+ struct dwapb_gpio *gpio = platform_get_drvdata(pdev);
+ struct bgpio_chip *bgc = &gpio->ports[0].bgc;
+ unsigned long flags;
+
+ spin_lock_irqsave(&bgc->lock, flags);
+
+ saved_regs.int_mask = dwapb_read(gpio, GPIO_INTMASK);
+ saved_regs.int_en = dwapb_read(gpio, GPIO_INTEN);
+ saved_regs.int_deb = dwapb_read(gpio, GPIO_PORTA_DEBOUNCE);
+ saved_regs.int_pol = dwapb_read(gpio, GPIO_INT_POLARITY);
+ saved_regs.int_type = dwapb_read(gpio, GPIO_INTTYPE_LEVEL);
+ saved_regs.dir = dwapb_read(gpio, GPIO_SWPORTA_DDR);
+ saved_regs.data = dwapb_read(gpio, GPIO_SWPORTA_DR);
+
+ /* Mask out interrupts */
+ dwapb_write(gpio, GPIO_INTMASK, 0xffffffff);
+
+ spin_unlock_irqrestore(&bgc->lock, flags);
+
+ return 0;
+}
+
+static int dwapb_gpio_resume(struct device *dev)
+{
+ struct platform_device *pdev = to_platform_device(dev);
+ struct dwapb_gpio *gpio = platform_get_drvdata(pdev);
+ struct bgpio_chip *bgc = &gpio->ports[0].bgc;
+ unsigned long flags;
+
+ spin_lock_irqsave(&bgc->lock, flags);
+
+ dwapb_write(gpio, GPIO_SWPORTA_DR, saved_regs.data);
+ dwapb_write(gpio, GPIO_SWPORTA_DDR, saved_regs.dir);
+ dwapb_write(gpio, GPIO_INTTYPE_LEVEL, saved_regs.int_type);
+ dwapb_write(gpio, GPIO_INT_POLARITY, saved_regs.int_pol);
+ dwapb_write(gpio, GPIO_PORTA_DEBOUNCE, saved_regs.int_deb);
+ dwapb_write(gpio, GPIO_INTEN, saved_regs.int_en);
+ dwapb_write(gpio, GPIO_INTMASK, saved_regs.int_mask);
+
+ /* Clear out spurious interrupts */
+ dwapb_write(gpio, GPIO_PORTA_EOI, 0xffffffff);
+
+ spin_unlock_irqrestore(&bgc->lock, flags);
+
+ return 0;
+}
+#endif
+
+static SIMPLE_DEV_PM_OPS(dwapb_gpio_pm_ops, dwapb_gpio_suspend,
+ dwapb_gpio_resume);
+
static struct platform_driver dwapb_gpio_driver = {
.driver = {
.name = "gpio-dwapb",
.owner = THIS_MODULE,
+ .pm = &dwapb_gpio_pm_ops,
.of_match_table = of_match_ptr(dwapb_of_match),
},
.probe = dwapb_gpio_probe,
--
1.7.9.5
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