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.k...@intel.com>
Signed-off-by: Weike Chen <alvin.c...@intel.com>
---
drivers/gpio/gpio-dwapb.c | 109 +++++++++++++++++++++++++++++++++++++++++++++
1 file changed, 109 insertions(+)
diff --git a/drivers/gpio/gpio-dwapb.c b/drivers/gpio/gpio-dwapb.c
index 9a76e3c..14d83af 100644
--- a/drivers/gpio/gpio-dwapb.c
+++ b/drivers/gpio/gpio-dwapb.c
@@ -50,11 +50,14 @@
#define GPIO_SWPORT_DDR_SIZE (GPIO_SWPORTB_DDR - GPIO_SWPORTA_DDR)
struct dwapb_gpio;
+struct dwapb_context;
struct dwapb_gpio_port {
struct bgpio_chip bgc;
bool is_registered;
struct dwapb_gpio *gpio;
+ struct dwapb_context *ctx;
+ unsigned int idx;
};
struct dwapb_gpio {
@@ -377,6 +380,7 @@ static int dwapb_gpio_add_port(struct dwapb_gpio *gpio,
port = &gpio->ports[offs];
port->gpio = gpio;
+ port->idx = pp->idx;
dat = gpio->regs + GPIO_EXT_PORTA + (pp->idx * GPIO_EXT_PORT_SIZE);
set = gpio->regs + GPIO_SWPORTA_DR + (pp->idx * GPIO_SWPORT_DR_SIZE);
@@ -584,10 +588,115 @@ static const struct of_device_id dwapb_of_match[] = {
};
MODULE_DEVICE_TABLE(of, dwapb_of_match);
+#ifdef CONFIG_PM_SLEEP
+/* Store GPIO context across system-wide suspend/resume transitions */
+struct dwapb_context {
+ u32 data;
+ u32 dir;
+ u32 ext;
+ u32 int_en;
+ u32 int_mask;
+ u32 int_type;
+ u32 int_pol;
+ u32 int_deb;
+};
+
+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;
+ int i;
+
+ spin_lock_irqsave(&bgc->lock, flags);
+ for (i = 0; i < gpio->nr_ports; i++) {
+ unsigned int offset;
+ unsigned int idx = gpio->ports[i].idx;
+ struct dwapb_context *ctx = gpio->ports[i].ctx;
+
+ if (!ctx) {
+ ctx = devm_kzalloc(dev, sizeof(*ctx), GFP_KERNEL);
+ gpio->ports[i].ctx = ctx;
+ }
+
+ offset = GPIO_SWPORTA_DDR + (idx * GPIO_SWPORT_DDR_SIZE);
+ ctx->dir = dwapb_read(gpio, offset);
+
+ offset = GPIO_SWPORTA_DR + (idx * GPIO_SWPORT_DR_SIZE);
+ ctx->data = dwapb_read(gpio, offset);
+
+ offset = GPIO_EXT_PORTA + (idx * GPIO_EXT_PORT_SIZE);
+ ctx->ext = dwapb_read(gpio, offset);
+
+ /* Only port A can provide interrupts */
+ if (idx == 0) {
+ ctx->int_mask = dwapb_read(gpio, GPIO_INTMASK);
+ ctx->int_en = dwapb_read(gpio, GPIO_INTEN);
+ ctx->int_pol = dwapb_read(gpio, GPIO_INT_POLARITY);
+ ctx->int_type = dwapb_read(gpio, GPIO_INTTYPE_LEVEL);
+ ctx->int_deb = dwapb_read(gpio, GPIO_PORTA_DEBOUNCE);
+
+ /* 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;
+ int i;
+
+ spin_lock_irqsave(&bgc->lock, flags);
+ for (i = 0; i < gpio->nr_ports; i++) {
+ unsigned int offset;
+ unsigned int idx = gpio->ports[i].idx;
+ struct dwapb_context *ctx = gpio->ports[i].ctx;
+
+ BUG_ON(ctx == 0);
+
+ offset = GPIO_SWPORTA_DR + (idx * GPIO_SWPORT_DR_SIZE);
+ dwapb_write(gpio, offset, ctx->data);
+
+ offset = GPIO_SWPORTA_DDR + (idx * GPIO_SWPORT_DDR_SIZE);
+ dwapb_write(gpio, offset, ctx->dir);
+
+ offset = GPIO_EXT_PORTA + (idx * GPIO_EXT_PORT_SIZE);
+ dwapb_write(gpio, offset, ctx->ext);
+
+ /* Only port A can provide interrupts */
+ if (idx == 0) {
+ dwapb_write(gpio, GPIO_INTTYPE_LEVEL, ctx->int_type);
+ dwapb_write(gpio, GPIO_INT_POLARITY, ctx->int_pol);
+ dwapb_write(gpio, GPIO_PORTA_DEBOUNCE, ctx->int_deb);
+ dwapb_write(gpio, GPIO_INTEN, ctx->int_en);
+ dwapb_write(gpio, GPIO_INTMASK, ctx->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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