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Commit b62a9c20 authored by Linus Torvalds's avatar Linus Torvalds
Browse files

Merge tag 'gpio-v3.19-4' of git://git.kernel.org/pub/scm/linux/kernel/git/linusw/linux-gpio 

Pull GPIO fixes from Linus Walleij:
 "Here is a set of fixes that mainly appeared when Johan Hovold started
  exercising the removal path of the GPIO library, dealing with
  hotplugging of GPIO controllers. Details from tag:

  A slew of fixes dealing with some irritating bugs (non-regressions)
  that have been around forever in the GPIO subsystem, most of them also
  tagged for stable:

   - A large slew of fixes from Johan Hovold who is finally testing and
     reviewing the removal path of the GPIO drivers.

   - Fix of_get_named_gpiod_flags() so it works as expected.

   - Fix an IRQ handling bug in the crystalcove driver"

* tag 'gpio-v3.19-4' of git://git.kernel.org/pub/scm/linux/kernel/git/linusw/linux-gpio:
  gpiolib: of: Correct error handling in of_get_named_gpiod_flags
  gpio: sysfs: fix gpio attribute-creation race
  gpio: sysfs: fix gpio device-attribute leak
  gpio: sysfs: fix gpio-chip device-attribute leak
  gpio: unregister gpiochip device before removing it
  gpio: fix sleep-while-atomic in gpiochip_remove
  gpio: fix memory leak and sleep-while-atomic
  gpio: clean up gpiochip_add error handling
  gpio: fix gpio-chip list corruption
  gpio: fix memory and reference leaks in gpiochip_add error path
  gpio: crystalcove: use handle_nested_irq
parents 66893885 7b8792bb

drivers/gpio/gpio-crystalcove.c

+1 −1
Original line number Diff line number Diff line
@@ -272,7 +272,7 @@ static irqreturn_t crystalcove_gpio_irq_handler(int irq, void *data) 
	for (gpio = 0; gpio < CRYSTALCOVE_GPIO_NUM; gpio++) {

		if (pending & BIT(gpio)) {

			virq = irq_find_mapping(cg->chip.irqdomain, gpio);

			generic_handle_irq(virq);

			handle_nested_irq(virq);

		}

	}

drivers/gpio/gpiolib-of.c

+8 −2
Original line number Diff line number Diff line
@@ -45,8 +45,14 @@ static int of_gpiochip_find_and_xlate(struct gpio_chip *gc, void *data) 
		return false;



	ret = gc->of_xlate(gc, &gg_data->gpiospec, gg_data->flags);

	if (ret < 0)

		return false;

	if (ret < 0) {

		/* We've found the gpio chip, but the translation failed.

		 * Return true to stop looking and return the translation

		 * error via out_gpio

		 */

		gg_data->out_gpio = ERR_PTR(ret);

		return true;

	 }



	gg_data->out_gpio = gpiochip_get_desc(gc, ret);

	return true;

drivers/gpio/gpiolib-sysfs.c

+52 −40
Original line number Diff line number Diff line
@@ -128,7 +128,7 @@ static ssize_t gpio_value_store(struct device *dev, 
	return status;

}



static const DEVICE_ATTR(value, 0644,

static DEVICE_ATTR(value, 0644,

		gpio_value_show, gpio_value_store);



static irqreturn_t gpio_sysfs_irq(int irq, void *priv)
@@ -353,17 +353,46 @@ static ssize_t gpio_active_low_store(struct device *dev, 
	return status ? : size;

}



static const DEVICE_ATTR(active_low, 0644,

static DEVICE_ATTR(active_low, 0644,

		gpio_active_low_show, gpio_active_low_store);



static const struct attribute *gpio_attrs[] = {

static umode_t gpio_is_visible(struct kobject *kobj, struct attribute *attr,

			       int n)

{

	struct device *dev = container_of(kobj, struct device, kobj);

	struct gpio_desc *desc = dev_get_drvdata(dev);

	umode_t mode = attr->mode;

	bool show_direction = test_bit(FLAG_SYSFS_DIR, &desc->flags);



	if (attr == &dev_attr_direction.attr) {

		if (!show_direction)

			mode = 0;

	} else if (attr == &dev_attr_edge.attr) {

		if (gpiod_to_irq(desc) < 0)

			mode = 0;

		if (!show_direction && test_bit(FLAG_IS_OUT, &desc->flags))

			mode = 0;

	}



	return mode;

}



static struct attribute *gpio_attrs[] = {

	&dev_attr_direction.attr,

	&dev_attr_edge.attr,

	&dev_attr_value.attr,

	&dev_attr_active_low.attr,

	NULL,

};



static const struct attribute_group gpio_attr_group = {

	.attrs = (struct attribute **) gpio_attrs,

static const struct attribute_group gpio_group = {

	.attrs = gpio_attrs,

	.is_visible = gpio_is_visible,

};



static const struct attribute_group *gpio_groups[] = {

	&gpio_group,

	NULL

};



/*
@@ -400,16 +429,13 @@ static ssize_t chip_ngpio_show(struct device *dev, 
}

static DEVICE_ATTR(ngpio, 0444, chip_ngpio_show, NULL);



static const struct attribute *gpiochip_attrs[] = {

static struct attribute *gpiochip_attrs[] = {

	&dev_attr_base.attr,

	&dev_attr_label.attr,

	&dev_attr_ngpio.attr,

	NULL,

};



static const struct attribute_group gpiochip_attr_group = {

	.attrs = (struct attribute **) gpiochip_attrs,

};

ATTRIBUTE_GROUPS(gpiochip);



/*

 * /sys/class/gpio/export ... write-only
@@ -556,45 +582,30 @@ int gpiod_export(struct gpio_desc *desc, bool direction_may_change) 
		goto fail_unlock;

	}



	if (!desc->chip->direction_input || !desc->chip->direction_output)

		direction_may_change = false;

	if (desc->chip->direction_input && desc->chip->direction_output &&

			direction_may_change) {

		set_bit(FLAG_SYSFS_DIR, &desc->flags);

	}



	spin_unlock_irqrestore(&gpio_lock, flags);



	offset = gpio_chip_hwgpio(desc);

	if (desc->chip->names && desc->chip->names[offset])

		ioname = desc->chip->names[offset];



	dev = device_create(&gpio_class, desc->chip->dev, MKDEV(0, 0),

			    desc, ioname ? ioname : "gpio%u",

	dev = device_create_with_groups(&gpio_class, desc->chip->dev,

					MKDEV(0, 0), desc, gpio_groups,

					ioname ? ioname : "gpio%u",

					desc_to_gpio(desc));

	if (IS_ERR(dev)) {

		status = PTR_ERR(dev);

		goto fail_unlock;

	}



	status = sysfs_create_group(&dev->kobj, &gpio_attr_group);

	if (status)

		goto fail_unregister_device;



	if (direction_may_change) {

		status = device_create_file(dev, &dev_attr_direction);

		if (status)

			goto fail_unregister_device;

	}



	if (gpiod_to_irq(desc) >= 0 && (direction_may_change ||

				       !test_bit(FLAG_IS_OUT, &desc->flags))) {

		status = device_create_file(dev, &dev_attr_edge);

		if (status)

			goto fail_unregister_device;

	}



	set_bit(FLAG_EXPORT, &desc->flags);

	mutex_unlock(&sysfs_lock);

	return 0;



fail_unregister_device:

	device_unregister(dev);

fail_unlock:

	mutex_unlock(&sysfs_lock);

	gpiod_dbg(desc, "%s: status %d\n", __func__, status);
@@ -718,6 +729,7 @@ void gpiod_unexport(struct gpio_desc *desc) 
		dev = class_find_device(&gpio_class, NULL, desc, match_export);

		if (dev) {

			gpio_setup_irq(desc, dev, 0);

			clear_bit(FLAG_SYSFS_DIR, &desc->flags);

			clear_bit(FLAG_EXPORT, &desc->flags);

		} else

			status = -ENODEV;
@@ -750,13 +762,13 @@ int gpiochip_export(struct gpio_chip *chip) 


	/* use chip->base for the ID; it's already known to be unique */

	mutex_lock(&sysfs_lock);

	dev = device_create(&gpio_class, chip->dev, MKDEV(0, 0), chip,

	dev = device_create_with_groups(&gpio_class, chip->dev, MKDEV(0, 0),

					chip, gpiochip_groups,

					"gpiochip%d", chip->base);

	if (!IS_ERR(dev)) {

		status = sysfs_create_group(&dev->kobj,

				&gpiochip_attr_group);

	} else

	if (IS_ERR(dev))

		status = PTR_ERR(dev);

	else

		status = 0;

	chip->exported = (status == 0);

	mutex_unlock(&sysfs_lock);

drivers/gpio/gpiolib.c

+30 −28
Original line number Diff line number Diff line
@@ -248,29 +248,30 @@ int gpiochip_add(struct gpio_chip *chip) 
		base = gpiochip_find_base(chip->ngpio);

		if (base < 0) {

			status = base;

			goto unlock;

			spin_unlock_irqrestore(&gpio_lock, flags);

			goto err_free_descs;

		}

		chip->base = base;

	}



	status = gpiochip_add_to_list(chip);

	if (status) {

		spin_unlock_irqrestore(&gpio_lock, flags);

		goto err_free_descs;

	}



	if (status == 0) {

	for (id = 0; id < chip->ngpio; id++) {

		struct gpio_desc *desc = &descs[id];



		desc->chip = chip;



			/* REVISIT:  most hardware initializes GPIOs as

			 * inputs (often with pullups enabled) so power

			 * usage is minimized.  Linux code should set the

			 * gpio direction first thing; but until it does,

			 * and in case chip->get_direction is not set,

			 * we may expose the wrong direction in sysfs.

		/* REVISIT: most hardware initializes GPIOs as inputs (often

		 * with pullups enabled) so power usage is minimized. Linux

		 * code should set the gpio direction first thing; but until

		 * it does, and in case chip->get_direction is not set, we may

		 * expose the wrong direction in sysfs.

		 */

			desc->flags = !chip->direction_input

				? (1 << FLAG_IS_OUT)

				: 0;

		}

		desc->flags = !chip->direction_input ? (1 << FLAG_IS_OUT) : 0;

	}



	chip->desc = descs;
@@ -284,12 +285,9 @@ int gpiochip_add(struct gpio_chip *chip) 
	of_gpiochip_add(chip);

	acpi_gpiochip_add(chip);



	if (status)

		goto fail;



	status = gpiochip_export(chip);

	if (status)

		goto fail;

		goto err_remove_chip;



	pr_debug("%s: registered GPIOs %d to %d on device: %s\n", __func__,

		chip->base, chip->base + chip->ngpio - 1,
@@ -297,11 +295,15 @@ int gpiochip_add(struct gpio_chip *chip) 


	return 0;



unlock:

err_remove_chip:

	acpi_gpiochip_remove(chip);

	of_gpiochip_remove(chip);

	spin_lock_irqsave(&gpio_lock, flags);

	list_del(&chip->list);

	spin_unlock_irqrestore(&gpio_lock, flags);

fail:

	kfree(descs);

	chip->desc = NULL;

err_free_descs:

	kfree(descs);



	/* failures here can mean systems won't boot... */

	pr_err("%s: GPIOs %d..%d (%s) failed to register\n", __func__,
@@ -325,14 +327,15 @@ void gpiochip_remove(struct gpio_chip *chip) 
	unsigned long	flags;

	unsigned	id;



	acpi_gpiochip_remove(chip);



	spin_lock_irqsave(&gpio_lock, flags);

	gpiochip_unexport(chip);



	gpiochip_irqchip_remove(chip);



	acpi_gpiochip_remove(chip);

	gpiochip_remove_pin_ranges(chip);

	of_gpiochip_remove(chip);



	spin_lock_irqsave(&gpio_lock, flags);

	for (id = 0; id < chip->ngpio; id++) {

		if (test_bit(FLAG_REQUESTED, &chip->desc[id].flags))

			dev_crit(chip->dev, "REMOVING GPIOCHIP WITH GPIOS STILL REQUESTED\n");
@@ -342,7 +345,6 @@ void gpiochip_remove(struct gpio_chip *chip) 


	list_del(&chip->list);

	spin_unlock_irqrestore(&gpio_lock, flags);

	gpiochip_unexport(chip);



	kfree(chip->desc);

	chip->desc = NULL;

drivers/gpio/gpiolib.h

+1 −0
Original line number Diff line number Diff line
@@ -77,6 +77,7 @@ struct gpio_desc { 
#define FLAG_OPEN_DRAIN	7	/* Gpio is open drain type */

#define FLAG_OPEN_SOURCE 8	/* Gpio is open source type */

#define FLAG_USED_AS_IRQ 9	/* GPIO is connected to an IRQ */

#define FLAG_SYSFS_DIR	10	/* show sysfs direction attribute */



#define ID_SHIFT	16	/* add new flags before this one */