diff mbox

[2/2] gpio: xilinx: Add clock support

Message ID 1478581990-28276-2-git-send-email-shubhrajyoti.datta@xilinx.com
State New
Headers show

Commit Message

Shubhrajyoti Datta Nov. 8, 2016, 5:13 a.m. UTC
Add basic clock support for xilinx gpio.

Signed-off-by: Shubhrajyoti Datta <shubhrajyoti.datta@xilinx.com>
---
 drivers/gpio/gpio-xilinx.c |   22 ++++++++++++++++++++++
 1 files changed, 22 insertions(+), 0 deletions(-)

Comments

Soren Brinkmann Nov. 8, 2016, 2:52 p.m. UTC | #1
On Tue, 2016-11-08 at 10:43:10 +0530, Shubhrajyoti Datta wrote:
> Add basic clock support for xilinx gpio.
> 
> Signed-off-by: Shubhrajyoti Datta <shubhrajyoti.datta@xilinx.com>
> ---
>  drivers/gpio/gpio-xilinx.c |   22 ++++++++++++++++++++++
>  1 files changed, 22 insertions(+), 0 deletions(-)
> 
> diff --git a/drivers/gpio/gpio-xilinx.c b/drivers/gpio/gpio-xilinx.c
> index 14b2a62..923cab8 100644
> --- a/drivers/gpio/gpio-xilinx.c
> +++ b/drivers/gpio/gpio-xilinx.c
> @@ -13,6 +13,7 @@
>   */
>  
>  #include <linux/bitops.h>
> +#include <linux/clk.h>
>  #include <linux/init.h>
>  #include <linux/errno.h>
>  #include <linux/module.h>
> @@ -45,6 +46,7 @@
>   * @gpio_state: GPIO state shadow register
>   * @gpio_dir: GPIO direction shadow register
>   * @gpio_lock: Lock used for synchronization
> + * @clk: Clock resource for this controller
>   */
>  struct xgpio_instance {
>  	struct of_mm_gpio_chip mmchip;
> @@ -52,6 +54,7 @@ struct xgpio_instance {
>  	u32 gpio_state[2];
>  	u32 gpio_dir[2];
>  	spinlock_t gpio_lock[2];
> +	struct clk *clk;
>  };
>  
>  static inline int xgpio_index(struct xgpio_instance *chip, int gpio)
> @@ -282,6 +285,7 @@ static int xgpio_remove(struct platform_device *pdev)
>  	struct xgpio_instance *chip = platform_get_drvdata(pdev);
>  
>  	of_mm_gpiochip_remove(&chip->mmchip);
> +	clk_disable_unprepare(chip->clk);
>  
>  	return 0;
>  }
> @@ -307,6 +311,23 @@ static int xgpio_probe(struct platform_device *pdev)
>  
>  	platform_set_drvdata(pdev, chip);
>  
> +	/* Retrieve GPIO clock */
> +	chip->clk = devm_clk_get(&pdev->dev, NULL);
> +	if (IS_ERR(chip->clk)) {
> +		if (PTR_ERR(chip->clk) == -ENOENT) {
> +			dev_info(&pdev->dev, "No clocks found for clk\n");
> +			chip->clk = NULL;
> +		} else {
> +			dev_err(&pdev->dev, "axi clock error\n");
> +			return PTR_ERR(chip->clk);
> +		}
> +	}

In the bindings you document 'clocks' as required, but it's handled as
optional here. Things should be consistent and given that the existing
binding doesn't require clocks, we're probably stuck with having the
clock optional.

	Sören
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diff mbox

Patch

diff --git a/drivers/gpio/gpio-xilinx.c b/drivers/gpio/gpio-xilinx.c
index 14b2a62..923cab8 100644
--- a/drivers/gpio/gpio-xilinx.c
+++ b/drivers/gpio/gpio-xilinx.c
@@ -13,6 +13,7 @@ 
  */
 
 #include <linux/bitops.h>
+#include <linux/clk.h>
 #include <linux/init.h>
 #include <linux/errno.h>
 #include <linux/module.h>
@@ -45,6 +46,7 @@ 
  * @gpio_state: GPIO state shadow register
  * @gpio_dir: GPIO direction shadow register
  * @gpio_lock: Lock used for synchronization
+ * @clk: Clock resource for this controller
  */
 struct xgpio_instance {
 	struct of_mm_gpio_chip mmchip;
@@ -52,6 +54,7 @@  struct xgpio_instance {
 	u32 gpio_state[2];
 	u32 gpio_dir[2];
 	spinlock_t gpio_lock[2];
+	struct clk *clk;
 };
 
 static inline int xgpio_index(struct xgpio_instance *chip, int gpio)
@@ -282,6 +285,7 @@  static int xgpio_remove(struct platform_device *pdev)
 	struct xgpio_instance *chip = platform_get_drvdata(pdev);
 
 	of_mm_gpiochip_remove(&chip->mmchip);
+	clk_disable_unprepare(chip->clk);
 
 	return 0;
 }
@@ -307,6 +311,23 @@  static int xgpio_probe(struct platform_device *pdev)
 
 	platform_set_drvdata(pdev, chip);
 
+	/* Retrieve GPIO clock */
+	chip->clk = devm_clk_get(&pdev->dev, NULL);
+	if (IS_ERR(chip->clk)) {
+		if (PTR_ERR(chip->clk) == -ENOENT) {
+			dev_info(&pdev->dev, "No clocks found for clk\n");
+			chip->clk = NULL;
+		} else {
+			dev_err(&pdev->dev, "axi clock error\n");
+			return PTR_ERR(chip->clk);
+		}
+	}
+	status = clk_prepare_enable(chip->clk);
+	if (status) {
+		dev_err(&pdev->dev, "Unable to enable clock.\n");
+		return status;
+	}
+
 	/* Update GPIO state shadow register with default value */
 	of_property_read_u32(np, "xlnx,dout-default", &chip->gpio_state[0]);
 
@@ -362,6 +383,7 @@  static int xgpio_probe(struct platform_device *pdev)
 	if (status) {
 		pr_err("%s: error in probe function with status %d\n",
 		       np->full_name, status);
+		clk_disable_unprepare(chip->clk);
 		return status;
 	}