[1/2] gpio: xilinx: Add clock adaptation support
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Message ID 1581937039-12964-1-git-send-email-srinivas.neeli@xilinx.com
State New
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  • [1/2] gpio: xilinx: Add clock adaptation support
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Commit Message

Srinivas Neeli Feb. 17, 2020, 10:57 a.m. UTC
Add support of clock adaptation for AXI GPIO driver.

Signed-off-by: Srinivas Neeli <srinivas.neeli@xilinx.com>
---
 drivers/gpio/gpio-xilinx.c | 105 ++++++++++++++++++++++++++++++++++++++++++++-
 1 file changed, 103 insertions(+), 2 deletions(-)

Comments

Bartosz Golaszewski Feb. 18, 2020, 4:02 p.m. UTC | #1
pon., 17 lut 2020 o 11:57 Srinivas Neeli <srinivas.neeli@xilinx.com> napisał(a):
>
> Add support of clock adaptation for AXI GPIO driver.
>
> Signed-off-by: Srinivas Neeli <srinivas.neeli@xilinx.com>
> ---
>  drivers/gpio/gpio-xilinx.c | 105 ++++++++++++++++++++++++++++++++++++++++++++-
>  1 file changed, 103 insertions(+), 2 deletions(-)
>
> diff --git a/drivers/gpio/gpio-xilinx.c b/drivers/gpio/gpio-xilinx.c
> index a9748b5198e6..26753ae58295 100644
> --- a/drivers/gpio/gpio-xilinx.c
> +++ b/drivers/gpio/gpio-xilinx.c
> @@ -14,6 +14,8 @@
>  #include <linux/io.h>
>  #include <linux/gpio/driver.h>
>  #include <linux/slab.h>
> +#include <linux/pm_runtime.h>
> +#include <linux/clk.h>
>
>  /* Register Offset Definitions */
>  #define XGPIO_DATA_OFFSET   (0x0)      /* Data register  */
> @@ -38,6 +40,7 @@
>   * @gpio_state: GPIO state shadow register
>   * @gpio_dir: GPIO direction shadow register
>   * @gpio_lock: Lock used for synchronization
> + * @clk: clock resource for this driver
>   */
>  struct xgpio_instance {
>         struct gpio_chip gc;
> @@ -45,7 +48,8 @@ struct xgpio_instance {
>         unsigned int gpio_width[2];
>         u32 gpio_state[2];
>         u32 gpio_dir[2];
> -       spinlock_t gpio_lock[2];
> +       spinlock_t gpio_lock[2];        /* For serializing operations */
> +       struct clk *clk;
>  };
>
>  static inline int xgpio_index(struct xgpio_instance *chip, int gpio)
> @@ -255,6 +259,70 @@ 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 = 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 platform_device *pdev = to_platform_device(dev);
> +       int irq = platform_get_irq(pdev, 0);
> +       struct irq_data *data = irq_get_irq_data(irq);
> +
> +       if (!irqd_is_wakeup_set(data))
> +               return pm_runtime_force_suspend(dev);
> +
> +       return 0;
> +}
> +
> +static int __maybe_unused xgpio_resume(struct device *dev)
> +{
> +       struct platform_device *pdev = to_platform_device(dev);
> +       int irq = platform_get_irq(pdev, 0);
> +       struct irq_data *data = irq_get_irq_data(irq);
> +
> +       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_of_probe - Probe method for the GPIO device.
>   * @pdev: pointer to the platform device
> @@ -323,6 +391,8 @@ static int xgpio_probe(struct platform_device *pdev)
>         chip->gc.direction_output = xgpio_dir_out;
>         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);
> @@ -333,15 +403,45 @@ static int xgpio_probe(struct platform_device *pdev)
>                 return PTR_ERR(chip->regs);
>         }
>
> +       chip->clk = devm_clk_get(&pdev->dev, "s_axi_aclk");
> +       if (IS_ERR(chip->clk)) {
> +               if (PTR_ERR(chip->clk) != -ENOENT) {
> +                       if (PTR_ERR(chip->clk) != -EPROBE_DEFER)
> +                               dev_err(&pdev->dev, "Input clock not found\n");
> +                       return PTR_ERR(chip->clk);
> +               }
> +               /*
> +                * Clock framework support is optional, continue on
> +                * anyways if we don't find a matching clock.
> +                */

Why not use devm_clk_get_optional() then?

> +               chip->clk = NULL;
> +       }
> +       status = clk_prepare_enable(chip->clk);
> +       if (status < 0) {
> +               dev_err(&pdev->dev, "Failed to prepare clk\n");
> +               return status;
> +       }
> +       pm_runtime_enable(&pdev->dev);
> +       status = pm_runtime_get_sync(&pdev->dev);
> +       if (status < 0)
> +               goto err_unprepare_clk;
> +
>         xgpio_save_regs(chip);
>
>         status = devm_gpiochip_add_data(&pdev->dev, &chip->gc, chip);
>         if (status) {
>                 dev_err(&pdev->dev, "failed to add GPIO chip\n");
> -               return status;
> +               goto err_pm_put;
>         }
>
> +       pm_runtime_put(&pdev->dev);
>         return 0;
> +err_pm_put:
> +       pm_runtime_put(&pdev->dev);
> +err_unprepare_clk:
> +       pm_runtime_disable(&pdev->dev);
> +       clk_unprepare(chip->clk);
> +       return status;
>  }
>
>  static const struct of_device_id xgpio_of_match[] = {
> @@ -356,6 +456,7 @@ static struct platform_driver xgpio_plat_driver = {
>         .driver         = {
>                         .name = "gpio-xilinx",
>                         .of_match_table = xgpio_of_match,
> +                       .pm = &xgpio_dev_pm_ops,
>         },
>  };
>
> --
> 2.7.4
>
Srinivas Neeli Feb. 19, 2020, 11:23 a.m. UTC | #2
Hi,
I agree ,will address comments in V2.

> -----Original Message-----
> From: Bartosz Golaszewski <bgolaszewski@baylibre.com>
> Sent: Tuesday, February 18, 2020 9:33 PM
> To: Srinivas Neeli <sneeli@xilinx.com>
> Cc: Michal Simek <michals@xilinx.com>; Shubhrajyoti Datta
> <shubhraj@xilinx.com>; Srinivas Goud <sgoud@xilinx.com>; Linus Walleij
> <linus.walleij@linaro.org>; LKML <linux-kernel@vger.kernel.org>; arm-soc
> <linux-arm-kernel@lists.infradead.org>; linux-gpio <linux-
> gpio@vger.kernel.org>; git <git@xilinx.com>
> Subject: Re: [PATCH 1/2] gpio: xilinx: Add clock adaptation support
> 
> pon., 17 lut 2020 o 11:57 Srinivas Neeli <srinivas.neeli@xilinx.com> napisał(a):
> >
> > Add support of clock adaptation for AXI GPIO driver.
> >
> > Signed-off-by: Srinivas Neeli <srinivas.neeli@xilinx.com>
> > ---
> >  drivers/gpio/gpio-xilinx.c | 105
> > ++++++++++++++++++++++++++++++++++++++++++++-
> >  1 file changed, 103 insertions(+), 2 deletions(-)
> >
> > diff --git a/drivers/gpio/gpio-xilinx.c b/drivers/gpio/gpio-xilinx.c
> > index a9748b5198e6..26753ae58295 100644
> > --- a/drivers/gpio/gpio-xilinx.c
> > +++ b/drivers/gpio/gpio-xilinx.c
> > @@ -14,6 +14,8 @@
> >  #include <linux/io.h>
> >  #include <linux/gpio/driver.h>
> >  #include <linux/slab.h>
> > +#include <linux/pm_runtime.h>
> > +#include <linux/clk.h>
> >
> >  /* Register Offset Definitions */
> >  #define XGPIO_DATA_OFFSET   (0x0)      /* Data register  */
> > @@ -38,6 +40,7 @@
> >   * @gpio_state: GPIO state shadow register
> >   * @gpio_dir: GPIO direction shadow register
> >   * @gpio_lock: Lock used for synchronization
> > + * @clk: clock resource for this driver
> >   */
> >  struct xgpio_instance {
> >         struct gpio_chip gc;
> > @@ -45,7 +48,8 @@ struct xgpio_instance {
> >         unsigned int gpio_width[2];
> >         u32 gpio_state[2];
> >         u32 gpio_dir[2];
> > -       spinlock_t gpio_lock[2];
> > +       spinlock_t gpio_lock[2];        /* For serializing operations */
> > +       struct clk *clk;
> >  };
> >
> >  static inline int xgpio_index(struct xgpio_instance *chip, int gpio)
> > @@ -255,6 +259,70 @@ 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 = 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 platform_device *pdev = to_platform_device(dev);
> > +       int irq = platform_get_irq(pdev, 0);
> > +       struct irq_data *data = irq_get_irq_data(irq);
> > +
> > +       if (!irqd_is_wakeup_set(data))
> > +               return pm_runtime_force_suspend(dev);
> > +
> > +       return 0;
> > +}
> > +
> > +static int __maybe_unused xgpio_resume(struct device *dev) {
> > +       struct platform_device *pdev = to_platform_device(dev);
> > +       int irq = platform_get_irq(pdev, 0);
> > +       struct irq_data *data = irq_get_irq_data(irq);
> > +
> > +       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_of_probe - Probe method for the GPIO device.
> >   * @pdev: pointer to the platform device @@ -323,6 +391,8 @@ static
> > int xgpio_probe(struct platform_device *pdev)
> >         chip->gc.direction_output = xgpio_dir_out;
> >         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); @@ -333,15 +403,45 @@
> > static int xgpio_probe(struct platform_device *pdev)
> >                 return PTR_ERR(chip->regs);
> >         }
> >
> > +       chip->clk = devm_clk_get(&pdev->dev, "s_axi_aclk");
> > +       if (IS_ERR(chip->clk)) {
> > +               if (PTR_ERR(chip->clk) != -ENOENT) {
> > +                       if (PTR_ERR(chip->clk) != -EPROBE_DEFER)
> > +                               dev_err(&pdev->dev, "Input clock not found\n");
> > +                       return PTR_ERR(chip->clk);
> > +               }
> > +               /*
> > +                * Clock framework support is optional, continue on
> > +                * anyways if we don't find a matching clock.
> > +                */
> 
> Why not use devm_clk_get_optional() then?
> 
> > +               chip->clk = NULL;
> > +       }
> > +       status = clk_prepare_enable(chip->clk);
> > +       if (status < 0) {
> > +               dev_err(&pdev->dev, "Failed to prepare clk\n");
> > +               return status;
> > +       }
> > +       pm_runtime_enable(&pdev->dev);
> > +       status = pm_runtime_get_sync(&pdev->dev);
> > +       if (status < 0)
> > +               goto err_unprepare_clk;
> > +
> >         xgpio_save_regs(chip);
> >
> >         status = devm_gpiochip_add_data(&pdev->dev, &chip->gc, chip);
> >         if (status) {
> >                 dev_err(&pdev->dev, "failed to add GPIO chip\n");
> > -               return status;
> > +               goto err_pm_put;
> >         }
> >
> > +       pm_runtime_put(&pdev->dev);
> >         return 0;
> > +err_pm_put:
> > +       pm_runtime_put(&pdev->dev);
> > +err_unprepare_clk:
> > +       pm_runtime_disable(&pdev->dev);
> > +       clk_unprepare(chip->clk);
> > +       return status;
> >  }
> >
> >  static const struct of_device_id xgpio_of_match[] = { @@ -356,6
> > +456,7 @@ static struct platform_driver xgpio_plat_driver = {
> >         .driver         = {
> >                         .name = "gpio-xilinx",
> >                         .of_match_table = xgpio_of_match,
> > +                       .pm = &xgpio_dev_pm_ops,
> >         },
> >  };
> >
> > --
> > 2.7.4
> >

Patch
diff mbox series

diff --git a/drivers/gpio/gpio-xilinx.c b/drivers/gpio/gpio-xilinx.c
index a9748b5198e6..26753ae58295 100644
--- a/drivers/gpio/gpio-xilinx.c
+++ b/drivers/gpio/gpio-xilinx.c
@@ -14,6 +14,8 @@ 
 #include <linux/io.h>
 #include <linux/gpio/driver.h>
 #include <linux/slab.h>
+#include <linux/pm_runtime.h>
+#include <linux/clk.h>
 
 /* Register Offset Definitions */
 #define XGPIO_DATA_OFFSET   (0x0)	/* Data register  */
@@ -38,6 +40,7 @@ 
  * @gpio_state: GPIO state shadow register
  * @gpio_dir: GPIO direction shadow register
  * @gpio_lock: Lock used for synchronization
+ * @clk: clock resource for this driver
  */
 struct xgpio_instance {
 	struct gpio_chip gc;
@@ -45,7 +48,8 @@  struct xgpio_instance {
 	unsigned int gpio_width[2];
 	u32 gpio_state[2];
 	u32 gpio_dir[2];
-	spinlock_t gpio_lock[2];
+	spinlock_t gpio_lock[2];	/* For serializing operations */
+	struct clk *clk;
 };
 
 static inline int xgpio_index(struct xgpio_instance *chip, int gpio)
@@ -255,6 +259,70 @@  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 = 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 platform_device *pdev = to_platform_device(dev);
+	int irq = platform_get_irq(pdev, 0);
+	struct irq_data *data = irq_get_irq_data(irq);
+
+	if (!irqd_is_wakeup_set(data))
+		return pm_runtime_force_suspend(dev);
+
+	return 0;
+}
+
+static int __maybe_unused xgpio_resume(struct device *dev)
+{
+	struct platform_device *pdev = to_platform_device(dev);
+	int irq = platform_get_irq(pdev, 0);
+	struct irq_data *data = irq_get_irq_data(irq);
+
+	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_of_probe - Probe method for the GPIO device.
  * @pdev: pointer to the platform device
@@ -323,6 +391,8 @@  static int xgpio_probe(struct platform_device *pdev)
 	chip->gc.direction_output = xgpio_dir_out;
 	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);
@@ -333,15 +403,45 @@  static int xgpio_probe(struct platform_device *pdev)
 		return PTR_ERR(chip->regs);
 	}
 
+	chip->clk = devm_clk_get(&pdev->dev, "s_axi_aclk");
+	if (IS_ERR(chip->clk)) {
+		if (PTR_ERR(chip->clk) != -ENOENT) {
+			if (PTR_ERR(chip->clk) != -EPROBE_DEFER)
+				dev_err(&pdev->dev, "Input clock not found\n");
+			return PTR_ERR(chip->clk);
+		}
+		/*
+		 * Clock framework support is optional, continue on
+		 * anyways if we don't find a matching clock.
+		 */
+		chip->clk = NULL;
+	}
+	status = clk_prepare_enable(chip->clk);
+	if (status < 0) {
+		dev_err(&pdev->dev, "Failed to prepare clk\n");
+		return status;
+	}
+	pm_runtime_enable(&pdev->dev);
+	status = pm_runtime_get_sync(&pdev->dev);
+	if (status < 0)
+		goto err_unprepare_clk;
+
 	xgpio_save_regs(chip);
 
 	status = devm_gpiochip_add_data(&pdev->dev, &chip->gc, chip);
 	if (status) {
 		dev_err(&pdev->dev, "failed to add GPIO chip\n");
-		return status;
+		goto err_pm_put;
 	}
 
+	pm_runtime_put(&pdev->dev);
 	return 0;
+err_pm_put:
+	pm_runtime_put(&pdev->dev);
+err_unprepare_clk:
+	pm_runtime_disable(&pdev->dev);
+	clk_unprepare(chip->clk);
+	return status;
 }
 
 static const struct of_device_id xgpio_of_match[] = {
@@ -356,6 +456,7 @@  static struct platform_driver xgpio_plat_driver = {
 	.driver		= {
 			.name = "gpio-xilinx",
 			.of_match_table	= xgpio_of_match,
+			.pm = &xgpio_dev_pm_ops,
 	},
 };