gpiolib: Defer gpio device setup until after gpiolib initialization (159f3cd9) · Commits · 戴 / test

drivers/gpio/gpiolib.c

+67 −31

Original line number	Original line	Diff line number	Diff line
	@@ -68,6 +68,7 @@ LIST_HEAD(gpio_devices);
	static void gpiochip_free_hogs(struct gpio_chip *chip);		static void gpiochip_free_hogs(struct gpio_chip *chip);
	static void gpiochip_irqchip_remove(struct gpio_chip *gpiochip);		static void gpiochip_irqchip_remove(struct gpio_chip *gpiochip);

			static bool gpiolib_initialized;

	static inline void desc_set_label(struct gpio_desc d, const char label)		static inline void desc_set_label(struct gpio_desc d, const char label)
	{		{
	@@ -445,6 +446,58 @@ static void gpiodevice_release(struct device *dev)
	kfree(gdev);		kfree(gdev);
	}		}

			static int gpiochip_setup_dev(struct gpio_device *gdev)
			{
			int status;

			cdev_init(&gdev->chrdev, &gpio_fileops);
			gdev->chrdev.owner = THIS_MODULE;
			gdev->chrdev.kobj.parent = &gdev->dev.kobj;
			gdev->dev.devt = MKDEV(MAJOR(gpio_devt), gdev->id);
			status = cdev_add(&gdev->chrdev, gdev->dev.devt, 1);
			if (status < 0)
			chip_warn(gdev->chip, "failed to add char device %d:%d\n",
			MAJOR(gpio_devt), gdev->id);
			else
			chip_dbg(gdev->chip, "added GPIO chardev (%d:%d)\n",
			MAJOR(gpio_devt), gdev->id);
			status = device_add(&gdev->dev);
			if (status)
			goto err_remove_chardev;

			status = gpiochip_sysfs_register(gdev);
			if (status)
			goto err_remove_device;

			/* From this point, the .release() function cleans up gpio_device */
			gdev->dev.release = gpiodevice_release;
			get_device(&gdev->dev);
			pr_debug("%s: registered GPIOs %d to %d on device: %s (%s)\n",
			__func__, gdev->base, gdev->base + gdev->ngpio - 1,
			dev_name(&gdev->dev), gdev->chip->label ? : "generic");

			return 0;

			err_remove_device:
			device_del(&gdev->dev);
			err_remove_chardev:
			cdev_del(&gdev->chrdev);
			return status;
			}

			static void gpiochip_setup_devs(void)
			{
			struct gpio_device *gdev;
			int err;

			list_for_each_entry(gdev, &gpio_devices, list) {
			err = gpiochip_setup_dev(gdev);
			if (err)
			pr_err("%s: Failed to initialize gpio device (%d)\n",
			dev_name(&gdev->dev), err);
			}
			}

	/**		/**
	* gpiochip_add_data() - register a gpio_chip		* gpiochip_add_data() - register a gpio_chip
	* @chip: the chip to register, with chip->base initialized		* @chip: the chip to register, with chip->base initialized
	@@ -459,6 +512,9 @@ static void gpiodevice_release(struct device *dev)
	* the gpio framework's arch_initcall(). Otherwise sysfs initialization		* the gpio framework's arch_initcall(). Otherwise sysfs initialization
	* for GPIOs will fail rudely.		* for GPIOs will fail rudely.
	*		*
			* gpiochip_add_data() must only be called after gpiolib initialization,
			* ie after core_initcall().
			*
	* If chip->base is negative, this requests dynamic assignment of		* If chip->base is negative, this requests dynamic assignment of
	* a range of valid GPIOs.		* a range of valid GPIOs.
	*/		*/
	@@ -515,7 +571,7 @@ int gpiochip_add_data(struct gpio_chip chip, void data)
	if (chip->ngpio == 0) {		if (chip->ngpio == 0) {
	chip_err(chip, "tried to insert a GPIO chip with zero lines\n");		chip_err(chip, "tried to insert a GPIO chip with zero lines\n");
	status = -EINVAL;		status = -EINVAL;
	goto err_free_gdev;		goto err_free_descs;
	}		}

	if (chip->label)		if (chip->label)
	@@ -597,39 +653,16 @@ int gpiochip_add_data(struct gpio_chip chip, void data)
	* we get a device node entry in sysfs under		* we get a device node entry in sysfs under
	* /sys/bus/gpio/devices/gpiochipN/dev that can be used for		* /sys/bus/gpio/devices/gpiochipN/dev that can be used for
	* coldplug of device nodes and other udev business.		* coldplug of device nodes and other udev business.
			* We can do this only if gpiolib has been initialized.
			* Otherwise, defer until later.
	*/		*/
	cdev_init(&gdev->chrdev, &gpio_fileops);		if (gpiolib_initialized) {
	gdev->chrdev.owner = THIS_MODULE;		status = gpiochip_setup_dev(gdev);
	gdev->chrdev.kobj.parent = &gdev->dev.kobj;
	gdev->dev.devt = MKDEV(MAJOR(gpio_devt), gdev->id);
	status = cdev_add(&gdev->chrdev, gdev->dev.devt, 1);
	if (status < 0)
	chip_warn(chip, "failed to add char device %d:%d\n",
	MAJOR(gpio_devt), gdev->id);
	else
	chip_dbg(chip, "added GPIO chardev (%d:%d)\n",
	MAJOR(gpio_devt), gdev->id);
	status = device_add(&gdev->dev);
	if (status)		if (status)
	goto err_remove_chardev;		goto err_remove_chip;
			}
	status = gpiochip_sysfs_register(gdev);
	if (status)
	goto err_remove_device;

	/* From this point, the .release() function cleans up gpio_device */
	gdev->dev.release = gpiodevice_release;
	get_device(&gdev->dev);
	pr_debug("%s: registered GPIOs %d to %d on device: %s (%s)\n",
	__func__, gdev->base, gdev->base + gdev->ngpio - 1,
	dev_name(&gdev->dev), chip->label ? : "generic");

	return 0;		return 0;

	err_remove_device:
	device_del(&gdev->dev);
	err_remove_chardev:
	cdev_del(&gdev->chrdev);
	err_remove_chip:		err_remove_chip:
	acpi_gpiochip_remove(chip);		acpi_gpiochip_remove(chip);
	gpiochip_free_hogs(chip);		gpiochip_free_hogs(chip);
	@@ -2842,6 +2875,9 @@ static int __init gpiolib_dev_init(void)
	if (ret < 0) {		if (ret < 0) {
	pr_err("gpiolib: failed to allocate char dev region\n");		pr_err("gpiolib: failed to allocate char dev region\n");
	bus_unregister(&gpio_bus_type);		bus_unregister(&gpio_bus_type);
			} else {
			gpiolib_initialized = true;
			gpiochip_setup_devs();
	}		}
	return ret;		return ret;
	}		}

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