Re: [RESEND PATCH 1/2] extcon: gpio: Add dt support for the driver

From: Chanwoo Choi
Date: Tue Nov 11 2014 - 20:10:20 EST

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Hi George,

How do you test this patch? This patch cannot test it
because this patch has not compatible string for binding through DT.

You have to add following of_device_id for extcon-gpio:

+#if defined(CONFIG_OF)
+static const struct of_device_id gpio_extcon_of_match[] = {
+ { .compatible = "extcon-gpio", },
+ {},
+};
+MODULE_DEVICE_TABLE(of, gpio_extcon_of_match);
+#endif
+
static struct platform_driver gpio_extcon_driver = {
.probe = gpio_extcon_probe,
.remove = gpio_extcon_remove,
.driver = {
.name = "extcon-gpio",
.owner = THIS_MODULE,
+ .of_match_table = of_match_ptr(gpio_extcon_of_match),
.pm = &gpio_extcon_pm_ops,
},
};

On 11/06/2014 12:29 AM, George Cherian wrote:
> Add device tree support to extcon-gpio driver.
> Add devicetree binding documentation
>
> While at that
> - Cleanup the pdata as there are no users for the same.
> - Convert the driver to use gpiod_* API's.
> - Some gpio's can sleep while reading, so always use gpio_get_value_cansleep
> to get data. This fixes warning from gpiolib due to wrong API usage.
>
> Signed-off-by: George Cherian <george.cherian@xxxxxx>
> ---
> .../devicetree/bindings/extcon/extcon-gpio.txt | 21 ++++++
> drivers/extcon/extcon-gpio.c | 83 +++++++---------------
> include/linux/extcon/extcon-gpio.h | 59 ---------------
> 3 files changed, 46 insertions(+), 117 deletions(-)
> create mode 100644 Documentation/devicetree/bindings/extcon/extcon-gpio.txt
> delete mode 100644 include/linux/extcon/extcon-gpio.h
>
> diff --git a/Documentation/devicetree/bindings/extcon/extcon-gpio.txt b/Documentation/devicetree/bindings/extcon/extcon-gpio.txt
> new file mode 100644
> index 0000000..30aa2e1
> --- /dev/null
> +++ b/Documentation/devicetree/bindings/extcon/extcon-gpio.txt
> @@ -0,0 +1,21 @@
> +GPIO based EXTCON
> +
> +EXTCON GPIO
> +-----------
> +
> +Required Properties:
> + - compatible: should be:
> + * "linux,extcon-gpio"

I prefer to use simply "extcon-gpio" compatible" instead of "linux,extcon-gpio".

> + - gpios: specifies the gpio pin used.
> +
> +Optional Properties:
> + - debounce: Debounce time for GPIO IRQ in ms
> +
> +

Remove unneeded blank line.

> +Eg:
> +
> + extcon1: am43_usbid_extcon1 {

I want to change the example of extcon-gpio as following:
"extcon1: am43_usbid_extcon1" -> "usb_extcon: extcon-gpio0"

> + compatible = "linux,extcon-gpio";

ditto.

> + gpios = <&gpio3 12 GPIO_ACTIVE_HIGH>;
> + debounce = <20>;
> + };

You have to fix indentation of brace.

> diff --git a/drivers/extcon/extcon-gpio.c b/drivers/extcon/extcon-gpio.c
> index 72f19a3..85795de 100644
> --- a/drivers/extcon/extcon-gpio.c
> +++ b/drivers/extcon/extcon-gpio.c
> @@ -21,26 +21,23 @@
> */
>
> #include <linux/extcon.h>
> -#include <linux/extcon/extcon-gpio.h>
> #include <linux/gpio.h>
> #include <linux/init.h>
> #include <linux/interrupt.h>
> +#include <linux/irq.h>
> #include <linux/kernel.h>
> #include <linux/module.h>
> +#include <linux/of_gpio.h>
> #include <linux/platform_device.h>
> #include <linux/slab.h>
> #include <linux/workqueue.h>
>
> struct gpio_extcon_data {
> struct extcon_dev *edev;
> - unsigned gpio;
> - bool gpio_active_low;
> - const char *state_on;
> - const char *state_off;
> + struct gpio_desc *gpiod;
> int irq;
> struct delayed_work work;
> unsigned long debounce_jiffies;
> - bool check_on_resume;
> };
>
> static void gpio_extcon_work(struct work_struct *work)
> @@ -50,9 +47,7 @@ static void gpio_extcon_work(struct work_struct *work)
> container_of(to_delayed_work(work), struct gpio_extcon_data,
> work);
>
> - state = gpio_get_value(data->gpio);
> - if (data->gpio_active_low)
> - state = !state;
> + state = gpiod_get_value_cansleep(data->gpiod);
> extcon_set_state(data->edev, state);
> }
>
> @@ -65,34 +60,16 @@ static irqreturn_t gpio_irq_handler(int irq, void *dev_id)
> return IRQ_HANDLED;
> }
>
> -static ssize_t extcon_gpio_print_state(struct extcon_dev *edev, char *buf)
> -{
> - struct device *dev = edev->dev.parent;
> - struct gpio_extcon_data *extcon_data = dev_get_drvdata(dev);
> - const char *state;
> -
> - if (extcon_get_state(edev))
> - state = extcon_data->state_on;
> - else
> - state = extcon_data->state_off;
> -
> - if (state)
> - return sprintf(buf, "%s\n", state);
> - return -EINVAL;
> -}
> -
> static int gpio_extcon_probe(struct platform_device *pdev)
> {
> - struct gpio_extcon_platform_data *pdata = dev_get_platdata(&pdev->dev);
> + struct device_node *np = pdev->dev.of_node;
> struct gpio_extcon_data *extcon_data;
> + unsigned int irq_flags;
> + unsigned int debounce = 0;
> int ret;
>
> - if (!pdata)
> - return -EBUSY;
> - if (!pdata->irq_flags) {
> - dev_err(&pdev->dev, "IRQ flag is not specified.\n");
> + if (!np)
> return -EINVAL;
> - }
>
> extcon_data = devm_kzalloc(&pdev->dev, sizeof(struct gpio_extcon_data),
> GFP_KERNEL);
> @@ -104,27 +81,23 @@ static int gpio_extcon_probe(struct platform_device *pdev)
> dev_err(&pdev->dev, "failed to allocate extcon device\n");
> return -ENOMEM;
> }
> - extcon_data->edev->name = pdata->name;
> -
> - extcon_data->gpio = pdata->gpio;
> - extcon_data->gpio_active_low = pdata->gpio_active_low;
> - extcon_data->state_on = pdata->state_on;
> - extcon_data->state_off = pdata->state_off;
> - extcon_data->check_on_resume = pdata->check_on_resume;
> - if (pdata->state_on && pdata->state_off)
> - extcon_data->edev->print_state = extcon_gpio_print_state;
> -
> - ret = devm_gpio_request_one(&pdev->dev, extcon_data->gpio, GPIOF_DIR_IN,
> - pdev->name);
> - if (ret < 0)
> - return ret;
> + extcon_data->edev->name = np->name;
> + extcon_data->gpiod = gpiod_get(&pdev->dev, NULL);
> + if (IS_ERR(extcon_data->gpiod))
> + return PTR_ERR(extcon_data->gpiod);
>
> - if (pdata->debounce) {
> - ret = gpio_set_debounce(extcon_data->gpio,
> - pdata->debounce * 1000);
> + extcon_data->irq = gpiod_to_irq(extcon_data->gpiod);
> + if (extcon_data->irq < 0)
> + return extcon_data->irq;
> +
> + irq_flags = irq_get_trigger_type(extcon_data->irq);

I recommend to use interrupt flags as following:
irqflags = IRQF_TRIGGER_RISING | IRQF_TRIGGER_FALLING;

> + of_property_read_u32(np, "debounce", &debounce);

I don't want to use additional variable ('debounce').
You better to use 'data->debounce_jiffies' direclty instead of 'debounce'
Also, I prefer to check the return value of of_property_read_u32().

> + if (debounce) {
> + ret = gpiod_set_debounce(extcon_data->gpiod,
> + debounce * 1000);
> if (ret < 0)
> extcon_data->debounce_jiffies =
> - msecs_to_jiffies(pdata->debounce);
> + msecs_to_jiffies(debounce);
> }

How about following codes?

if (of_property_read_u32(np, "debounce", &data->debounce_jiffies))
data->debounce_jiffies = 0;

ret = gpiod_set_debounce(data->gpiod, data->debounce_jiffies * 1000);
if (ret < 0)
data->debounce_jiffies
= msecs_to_jiffies(data->debounce_jiffies);

>
> ret = devm_extcon_dev_register(&pdev->dev, extcon_data->edev);
> @@ -132,13 +105,8 @@ static int gpio_extcon_probe(struct platform_device *pdev)
> return ret;
>
> INIT_DELAYED_WORK(&extcon_data->work, gpio_extcon_work);
> -
> - extcon_data->irq = gpio_to_irq(extcon_data->gpio);
> - if (extcon_data->irq < 0)
> - return extcon_data->irq;
> -
> ret = request_any_context_irq(extcon_data->irq, gpio_irq_handler,
> - pdata->irq_flags, pdev->name,
> + irq_flags, pdev->name,
> extcon_data);
> if (ret < 0)
> return ret;
> @@ -166,9 +134,8 @@ static int gpio_extcon_resume(struct device *dev)
> struct gpio_extcon_data *extcon_data;
>
> extcon_data = dev_get_drvdata(dev);
> - if (extcon_data->check_on_resume)

Why did you remove 'check_on_resume' flag without any description?

> - queue_delayed_work(system_power_efficient_wq,
> - &extcon_data->work, extcon_data->debounce_jiffies);
> + queue_delayed_work(system_power_efficient_wq,
> + &extcon_data->work, extcon_data->debounce_jiffies);
>
> return 0;
> }
> diff --git a/include/linux/extcon/extcon-gpio.h b/include/linux/extcon/extcon-gpio.h
> deleted file mode 100644
> index 0b17ad4..0000000
> --- a/include/linux/extcon/extcon-gpio.h
> +++ /dev/null
> @@ -1,59 +0,0 @@
> -/*
> - * External connector (extcon) class generic GPIO driver
> - *
> - * Copyright (C) 2012 Samsung Electronics
> - * Author: MyungJoo Ham <myungjoo.ham@xxxxxxxxxxx>
> - *
> - * based on switch class driver
> - * Copyright (C) 2008 Google, Inc.
> - * Author: Mike Lockwood <lockwood@xxxxxxxxxxx>
> - *
> - * This software is licensed under the terms of the GNU General Public
> - * License version 2, as published by the Free Software Foundation, and
> - * may be copied, distributed, and modified under those terms.
> - *
> - * This program is distributed in the hope that it will be useful,
> - * but WITHOUT ANY WARRANTY; without even the implied warranty of
> - * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
> - * GNU General Public License for more details.
> - *
> -*/
> -#ifndef __EXTCON_GPIO_H__
> -#define __EXTCON_GPIO_H__ __FILE__
> -
> -#include <linux/extcon.h>
> -
> -/**
> - * struct gpio_extcon_platform_data - A simple GPIO-controlled extcon device.
> - * @name: The name of this GPIO extcon device.
> - * @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).
> - * @state_on: print_state is overriden with state_on if attached.
> - * If NULL, default method of extcon class is used.
> - * @state_off: print_state is overriden with state_off if detached.
> - * If NUll, default method of extcon class is used.
> - * @check_on_resume: Boolean describing whether to check the state of gpio
> - * while resuming from sleep.
> - *
> - * Note that in order for state_on or state_off to be valid, both state_on
> - * and state_off should be not NULL. If at least one of them is NULL,
> - * the print_state is not overriden.
> - */
> -struct gpio_extcon_platform_data {
> - const char *name;
> - unsigned gpio;
> - bool gpio_active_low;
> - unsigned long debounce;
> - unsigned long irq_flags;
> -
> - /* if NULL, "0" or "1" will be printed */
> - const char *state_on;
> - const char *state_off;
> - bool check_on_resume;
> -};
> -
> -#endif /* __EXTCON_GPIO_H__ */
>

Thanks,
Chanwoo Choi
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Next message: Mariusz Gorski: "[PATCH 4/4] staging: panel: Use better names for two defined values"
Previous message: Wanpeng Li: "[PATCH v5] sched/deadline: support dl task migration during cpu hotplug"
Messages sorted by: [ date ] [ thread ] [ subject ] [ author ]