gpio: zynq: Do PM initialization earlier to support gpio hogs

GPIO hogs registration is call at the end of gpiochip_add() function.
Calling sequence is:
gpiochip_add -> of_gpiochip_add -> of_gpiochip_scan_hogs ->
gpiod_hog -> gpiochip_request_own_desc -> __gpiod_request ->
chip->request -> zynq_gpio_request which calls pm_runtime_get_sync()
which returns -13 because PM is not initialized yet.

Initialize PM before gpiochip_add is called to fix this issue.

Signed-off-by: Michal Simek <michal.simek@xilinx.com>
Signed-off-by: Soren Brinkmann <soren.brinkmann@xilinx.com>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>

diff --git a/drivers/gpio/gpio-zynq.c b/drivers/gpio/gpio-zynq.c
index 8a04e00bef32c2f018ce20e6f0e240c98712b3f5..ba1150744b6160c08d5a95938bf47e0ebb355ac0 100644 (file)
--- a/drivers/gpio/gpio-zynq.c
+++ b/drivers/gpio/gpio-zynq.c
@@ -708,23 +708,23 @@ static int zynq_gpio_probe(struct platform_device *pdev)
        chip->base = -1;
        chip->ngpio = gpio->p_data->ngpio;
 
-       /* Enable GPIO clock */
+       /* Retrieve GPIO clock */
        gpio->clk = devm_clk_get(&pdev->dev, NULL);
        if (IS_ERR(gpio->clk)) {
                dev_err(&pdev->dev, "input clock not found.\n");
                return PTR_ERR(gpio->clk);
        }
-       ret = clk_prepare_enable(gpio->clk);
-       if (ret) {
-               dev_err(&pdev->dev, "Unable to enable clock.\n");
+
+       pm_runtime_enable(&pdev->dev);
+       ret = pm_runtime_get_sync(&pdev->dev);
+       if (ret < 0)
                return ret;
-       }
 
        /* report a bug if gpio chip registration fails */
        ret = gpiochip_add(chip);
        if (ret) {
                dev_err(&pdev->dev, "Failed to add gpio chip\n");
-               goto err_disable_clk;
+               goto err_pm_put;
        }
 
        /* disable interrupts for all banks */
@@ -742,15 +742,14 @@ static int zynq_gpio_probe(struct platform_device *pdev)
        gpiochip_set_chained_irqchip(chip, &zynq_gpio_edge_irqchip, gpio->irq,
                                     zynq_gpio_irqhandler);
 
-       pm_runtime_set_active(&pdev->dev);
-       pm_runtime_enable(&pdev->dev);
+       pm_runtime_put(&pdev->dev);
 
        return 0;
 
 err_rm_gpiochip:
        gpiochip_remove(chip);
-err_disable_clk:
-       clk_disable_unprepare(gpio->clk);
+err_pm_put:
+       pm_runtime_put(&pdev->dev);
 
        return ret;
 }