gpio: gpio-xilinx: Add support for suspend and resume

Add support for suspend and resume, pm runtime suspend and resume.
Added free and request calls.

Signed-off-by: Srinivas Neeli <srinivas.neeli@xilinx.com>
Reviewed-by: Linus Walleij <linus.walleij@linaro.org>
Signed-off-by: Bartosz Golaszewski <bgolaszewski@baylibre.com>

diff --git a/drivers/gpio/gpio-xilinx.c b/drivers/gpio/gpio-xilinx.c
index 62deb75..acd5747 100644 (file)
--- a/drivers/gpio/gpio-xilinx.c
+++ b/drivers/gpio/gpio-xilinx.c
@@ -16,6 +16,7 @@
 #include <linux/module.h>
 #include <linux/of_device.h>
 #include <linux/of_platform.h>
+#include <linux/pm_runtime.h>
 #include <linux/slab.h>
 
 /* Register Offset Definitions */
@@ -278,6 +279,39 @@ static void xgpio_save_regs(struct xgpio_instance *chip)
                       chip->gpio_dir[1]);
 }
 
+static int xgpio_request(struct gpio_chip *chip, unsigned int offset)
+{
+       int ret;
+
+       ret = pm_runtime_get_sync(chip->parent);
+       /*
+        * If the device is already active pm_runtime_get() will return 1 on
+        * success, but gpio_request still needs to return 0.
+        */
+       return ret < 0 ? ret : 0;
+}
+
+static void xgpio_free(struct gpio_chip *chip, unsigned int offset)
+{
+       pm_runtime_put(chip->parent);
+}
+
+static int __maybe_unused xgpio_suspend(struct device *dev)
+{
+       struct xgpio_instance *gpio = dev_get_drvdata(dev);
+       struct irq_data *data = irq_get_irq_data(gpio->irq);
+
+       if (!data) {
+               dev_err(dev, "irq_get_irq_data() failed\n");
+               return -EINVAL;
+       }
+
+       if (!irqd_is_wakeup_set(data))
+               return pm_runtime_force_suspend(dev);
+
+       return 0;
+}
+
 /**
  * xgpio_remove - Remove method for the GPIO device.
  * @pdev: pointer to the platform device
@@ -290,6 +324,9 @@ static int xgpio_remove(struct platform_device *pdev)
 {
        struct xgpio_instance *gpio = platform_get_drvdata(pdev);
 
+       pm_runtime_get_sync(&pdev->dev);
+       pm_runtime_put_noidle(&pdev->dev);
+       pm_runtime_disable(&pdev->dev);
        clk_disable_unprepare(gpio->clk);
 
        return 0;
@@ -305,6 +342,46 @@ static void xgpio_irq_ack(struct irq_data *irq_data)
 {
 }
 
+static int __maybe_unused xgpio_resume(struct device *dev)
+{
+       struct xgpio_instance *gpio = dev_get_drvdata(dev);
+       struct irq_data *data = irq_get_irq_data(gpio->irq);
+
+       if (!data) {
+               dev_err(dev, "irq_get_irq_data() failed\n");
+               return -EINVAL;
+       }
+
+       if (!irqd_is_wakeup_set(data))
+               return pm_runtime_force_resume(dev);
+
+       return 0;
+}
+
+static int __maybe_unused xgpio_runtime_suspend(struct device *dev)
+{
+       struct platform_device *pdev = to_platform_device(dev);
+       struct xgpio_instance *gpio = platform_get_drvdata(pdev);
+
+       clk_disable(gpio->clk);
+
+       return 0;
+}
+
+static int __maybe_unused xgpio_runtime_resume(struct device *dev)
+{
+       struct platform_device *pdev = to_platform_device(dev);
+       struct xgpio_instance *gpio = platform_get_drvdata(pdev);
+
+       return clk_enable(gpio->clk);
+}
+
+static const struct dev_pm_ops xgpio_dev_pm_ops = {
+       SET_SYSTEM_SLEEP_PM_OPS(xgpio_suspend, xgpio_resume)
+       SET_RUNTIME_PM_OPS(xgpio_runtime_suspend,
+                          xgpio_runtime_resume, NULL)
+};
+
 /**
  * xgpio_irq_mask - Write the specified signal of the GPIO device.
  * @irq_data: per IRQ and chip data passed down to chip functions
@@ -546,6 +623,8 @@ static int xgpio_probe(struct platform_device *pdev)
        chip->gc.of_gpio_n_cells = cells;
        chip->gc.get = xgpio_get;
        chip->gc.set = xgpio_set;
+       chip->gc.request = xgpio_request;
+       chip->gc.free = xgpio_free;
        chip->gc.set_multiple = xgpio_set_multiple;
 
        chip->gc.label = dev_name(&pdev->dev);
@@ -565,6 +644,9 @@ static int xgpio_probe(struct platform_device *pdev)
                dev_err(&pdev->dev, "Failed to prepare clk\n");
                return status;
        }
+       pm_runtime_get_noresume(&pdev->dev);
+       pm_runtime_set_active(&pdev->dev);
+       pm_runtime_enable(&pdev->dev);
 
        xgpio_save_regs(chip);
 
@@ -595,7 +677,7 @@ static int xgpio_probe(struct platform_device *pdev)
                                     GFP_KERNEL);
        if (!girq->parents) {
                status = -ENOMEM;
-               goto err_unprepare_clk;
+               goto err_pm_put;
        }
        girq->parents[0] = chip->irq;
        girq->default_type = IRQ_TYPE_NONE;
@@ -605,12 +687,15 @@ skip_irq:
        status = devm_gpiochip_add_data(&pdev->dev, &chip->gc, chip);
        if (status) {
                dev_err(&pdev->dev, "failed to add GPIO chip\n");
-               goto err_unprepare_clk;
+               goto err_pm_put;
        }
 
+       pm_runtime_put(&pdev->dev);
        return 0;
 
-err_unprepare_clk:
+err_pm_put:
+       pm_runtime_disable(&pdev->dev);
+       pm_runtime_put_noidle(&pdev->dev);
        clk_disable_unprepare(chip->clk);
        return status;
 }
@@ -628,6 +713,7 @@ static struct platform_driver xgpio_plat_driver = {
        .driver         = {
                        .name = "gpio-xilinx",
                        .of_match_table = xgpio_of_match,
+                       .pm = &xgpio_dev_pm_ops,
        },
 };