Re: [PATCH 4/8] extcon: gpio: Convert to fully use GPIO descriptor

From: Chanwoo Choi
Date: Mon Sep 25 2017 - 22:18:10 EST


Hi Linus,

Looks good to me. But, there is one comment
of gpiod_to_irq()'s return value.

If you modify it, feel free to add my tag:
Acked-by: Chanwoo Choi <cw00.choi@xxxxxxxxxxx>

On 2017ë 09ì 24ì 23:56, Linus Walleij wrote:
> Since we are not getting the GPIO from any platform data and global
> GPIO numberspace, we simply get the named "extcon" GPIO directly from
> the device. Cut away "active low" since GPIO descriptors already know
> if the line is active high or low. Simplify a bit with a
> struct device *dev helper variable in probe() and cut the complex
> init() function.
>
> Signed-off-by: Linus Walleij <linus.walleij@xxxxxxxxxx>
> ---
> drivers/extcon/extcon-gpio.c | 66 ++++++++++----------------------------------
> 1 file changed, 15 insertions(+), 51 deletions(-)
>
> diff --git a/drivers/extcon/extcon-gpio.c b/drivers/extcon/extcon-gpio.c
> index 9c4094edd123..86f3ec6d6014 100644
> --- a/drivers/extcon/extcon-gpio.c
> +++ b/drivers/extcon/extcon-gpio.c
> @@ -18,7 +18,6 @@
> */
>
> #include <linux/extcon.h>
> -#include <linux/gpio.h>
> #include <linux/gpio/consumer.h>
> #include <linux/init.h>
> #include <linux/interrupt.h>
> @@ -35,12 +34,8 @@
> * @work: Work fired by the interrupt.
> * @debounce_jiffies: Number of jiffies to wait for the GPIO to stabilize, from the debounce
> * value.
> - * @id_gpiod: GPIO descriptor for this external connector.
> + * @gpiod: GPIO descriptor for this external connector.
> * @extcon_id: The unique id of specific external connector.
> - * @gpio: Corresponding GPIO.
> - * @gpio_active_low: Boolean describing whether gpio active state is 1 or 0
> - * If true, low state of gpio means active.
> - * If false, high state of gpio means active.
> * @debounce: Debounce time for GPIO IRQ in ms.
> * @irq_flags: IRQ Flags (e.g., IRQF_TRIGGER_LOW).
> * @check_on_resume: Boolean describing whether to check the state of gpio
> @@ -51,10 +46,8 @@ struct gpio_extcon_data {
> int irq;
> struct delayed_work work;
> unsigned long debounce_jiffies;
> - struct gpio_desc *id_gpiod;
> + struct gpio_desc *gpiod;
> unsigned int extcon_id;
> - unsigned gpio;
> - bool gpio_active_low;
> unsigned long debounce;
> unsigned long irq_flags;
> bool check_on_resume;
> @@ -67,10 +60,7 @@ static void gpio_extcon_work(struct work_struct *work)
> container_of(to_delayed_work(work), struct gpio_extcon_data,
> work);
>
> - state = gpiod_get_value_cansleep(data->id_gpiod);
> - if (data->gpio_active_low)
> - state = !state;
> -
> + state = gpiod_get_value_cansleep(data->gpiod);
> extcon_set_state_sync(data->edev, data->extcon_id, state);
> }
>
> @@ -83,60 +73,34 @@ static irqreturn_t gpio_irq_handler(int irq, void *dev_id)
> return IRQ_HANDLED;
> }
>
> -static int gpio_extcon_init(struct device *dev, struct gpio_extcon_data *data)
> -{
> - int ret;
> -
> - ret = devm_gpio_request_one(dev, data->gpio, GPIOF_DIR_IN,
> - dev_name(dev));
> - if (ret < 0)
> - return ret;
> -
> - data->id_gpiod = gpio_to_desc(data->gpio);
> - if (!data->id_gpiod)
> - return -EINVAL;
> -
> - if (data->debounce) {
> - ret = gpiod_set_debounce(data->id_gpiod,
> - data->debounce * 1000);
> - if (ret < 0)
> - data->debounce_jiffies =
> - msecs_to_jiffies(data->debounce);
> - }
> -
> - data->irq = gpiod_to_irq(data->id_gpiod);
> - if (data->irq < 0)
> - return data->irq;
> -
> - return 0;
> -}
> -
> static int gpio_extcon_probe(struct platform_device *pdev)
> {
> struct gpio_extcon_data *data;
> + struct device *dev = &pdev->dev;
> int ret;
>
> - data = devm_kzalloc(&pdev->dev, sizeof(struct gpio_extcon_data),
> - GFP_KERNEL);
> + data = devm_kzalloc(dev, sizeof(struct gpio_extcon_data), GFP_KERNEL);
> if (!data)
> return -ENOMEM;
>
> if (!data->irq_flags || data->extcon_id > EXTCON_NONE)
> return -EINVAL;
>
> - /* Initialize the gpio */
> - ret = gpio_extcon_init(&pdev->dev, data);
> - if (ret < 0)
> - return ret;
> + data->gpiod = devm_gpiod_get(dev, "extcon", GPIOD_IN);
> + if (IS_ERR(data->gpiod))
> + return PTR_ERR(data->gpiod);
> + data->irq = gpiod_to_irq(data->gpiod);
> + if (data->irq <= 0)

"if (data->irq < 0)" is enough. If irq is zero, gpiod_to_irq()
returns the -ENXIO.

> + return data->irq;
>
> /* Allocate the memory of extcon devie and register extcon device */
> - data->edev = devm_extcon_dev_allocate(&pdev->dev, &data->extcon_id);
> + data->edev = devm_extcon_dev_allocate(dev, &data->extcon_id);
> if (IS_ERR(data->edev)) {
> - dev_err(&pdev->dev, "failed to allocate extcon device\n");
> + dev_err(dev, "failed to allocate extcon device\n");
> return -ENOMEM;
> }
>
> - ret = devm_extcon_dev_register(&pdev->dev, data->edev);
> + ret = devm_extcon_dev_register(dev, data->edev);
> if (ret < 0)
> return ret;
>
> @@ -146,7 +110,7 @@ static int gpio_extcon_probe(struct platform_device *pdev)
> * Request the interrupt of gpio to detect whether external connector
> * is attached or detached.
> */
> - ret = devm_request_any_context_irq(&pdev->dev, data->irq,
> + ret = devm_request_any_context_irq(dev, data->irq,
> gpio_irq_handler, data->irq_flags,
> pdev->name, data);
> if (ret < 0)
>


--
Best Regards,
Chanwoo Choi
Samsung Electronics