#define FLAG_TRIG_FALL 5 /* trigger on falling edge */
#define FLAG_TRIG_RISE 6 /* trigger on rising edge */
#define FLAG_ACTIVE_LOW 7 /* sysfs value has active low */
+#define FLAG_SYSFS_DIR 10 /* show sysfs direction attribute */
#define ID_SHIFT 16 /* add new flags before this one */
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)
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 mode_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);
+ unsigned gpio = desc - gpio_desc;
+ mode_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 (gpio_to_irq(gpio) < 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
};
/*
}
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
*/
int gpio_export(unsigned gpio, bool direction_may_change)
{
+ struct gpio_chip *chip;
unsigned long flags;
struct gpio_desc *desc;
- int status = -EINVAL;
+ int status;
const char *ioname = NULL;
+ struct device *dev;
/* can't export until sysfs is available ... */
if (!gpio_class.p) {
return -ENOENT;
}
- if (!gpio_is_valid(gpio))
- goto done;
+ if (!gpio_is_valid(gpio)) {
+ pr_debug("%s: gpio %d is not valid\n", __func__, gpio);
+ return -EINVAL;
+ }
+
+ desc = &gpio_desc[gpio];
+ chip = desc->chip;
mutex_lock(&sysfs_lock);
+ /* check if chip is being removed */
+ if (!chip || !chip->exported) {
+ status = -ENODEV;
+ goto fail_unlock;
+ }
+
spin_lock_irqsave(&gpio_lock, flags);
- desc = &gpio_desc[gpio];
- if (test_bit(FLAG_REQUESTED, &desc->flags)
- && !test_bit(FLAG_EXPORT, &desc->flags)) {
- status = 0;
- if (!desc->chip->direction_input
- || !desc->chip->direction_output)
- direction_may_change = false;
+ if (!test_bit(FLAG_REQUESTED, &desc->flags) ||
+ test_bit(FLAG_EXPORT, &desc->flags)) {
+ spin_unlock_irqrestore(&gpio_lock, flags);
+ pr_debug("%s: gpio %d unavailable (requested=%d, exported=%d)\n",
+ __func__, gpio,
+ test_bit(FLAG_REQUESTED, &desc->flags),
+ test_bit(FLAG_EXPORT, &desc->flags));
+ return -EPERM;
}
+
+ 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);
if (desc->chip->names && desc->chip->names[gpio - desc->chip->base])
ioname = desc->chip->names[gpio - desc->chip->base];
- if (status == 0) {
- struct device *dev;
-
- dev = device_create(&gpio_class, desc->chip->dev, MKDEV(0, 0),
- desc, ioname ? ioname : "gpio%u", gpio);
- if (!IS_ERR(dev)) {
- status = sysfs_create_group(&dev->kobj,
- &gpio_attr_group);
-
- if (!status && direction_may_change)
- status = device_create_file(dev,
- &dev_attr_direction);
-
- if (!status && gpio_to_irq(gpio) >= 0
- && (direction_may_change
- || !test_bit(FLAG_IS_OUT,
- &desc->flags)))
- status = device_create_file(dev,
- &dev_attr_edge);
-
- if (status != 0)
- device_unregister(dev);
- } else
- status = PTR_ERR(dev);
- if (status == 0)
- set_bit(FLAG_EXPORT, &desc->flags);
+ dev = device_create_with_groups(&gpio_class, desc->chip->dev,
+ MKDEV(0, 0), desc, gpio_groups,
+ ioname ? ioname : "gpio%u", gpio);
+ if (IS_ERR(dev)) {
+ status = PTR_ERR(dev);
+ goto fail_unlock;
}
+ set_bit(FLAG_EXPORT, &desc->flags);
mutex_unlock(&sysfs_lock);
+ return 0;
-done:
- if (status)
- pr_debug("%s: gpio%d status %d\n", __func__, gpio, status);
-
+fail_unlock:
+ mutex_unlock(&sysfs_lock);
+ pr_debug("%s: gpio%d status %d\n", __func__, gpio, status);
return status;
}
EXPORT_SYMBOL_GPL(gpio_export);
if (tdev != NULL) {
status = sysfs_create_link(&dev->kobj, &tdev->kobj,
name);
+ put_device(tdev);
} else {
status = -ENODEV;
}
}
status = sysfs_set_active_low(desc, dev, value);
-
+ put_device(dev);
unlock:
mutex_unlock(&sysfs_lock);
{
struct gpio_desc *desc;
int status = 0;
+ struct device *dev = NULL;
if (!gpio_is_valid(gpio)) {
status = -EINVAL;
desc = &gpio_desc[gpio];
if (test_bit(FLAG_EXPORT, &desc->flags)) {
- struct device *dev = NULL;
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);
- put_device(dev);
- device_unregister(dev);
} else
status = -ENODEV;
}
mutex_unlock(&sysfs_lock);
+ if (dev) {
+ device_unregister(dev);
+ put_device(dev);
+ }
done:
if (status)
pr_debug("%s: gpio%d status %d\n", __func__, gpio, status);
/* 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,
- "gpiochip%d", chip->base);
- if (!IS_ERR(dev)) {
- status = sysfs_create_group(&dev->kobj,
- &gpiochip_attr_group);
- } else
+ dev = device_create_with_groups(&gpio_class, chip->dev, MKDEV(0, 0),
+ chip, gpiochip_groups,
+ "gpiochip%d", chip->base);
+ if (IS_ERR(dev))
status = PTR_ERR(dev);
+ else
+ status = 0;
chip->exported = (status == 0);
mutex_unlock(&sysfs_lock);
{
int status;
struct device *dev;
+ struct gpio_desc *desc;
+ unsigned int i;
mutex_lock(&sysfs_lock);
dev = class_find_device(&gpio_class, NULL, chip, match_export);
if (dev) {
put_device(dev);
device_unregister(dev);
+ /* prevent further gpiod exports */
chip->exported = 0;
status = 0;
} else
if (status)
pr_debug("%s: chip %s status %d\n", __func__,
chip->label, status);
+
+ /* unregister gpio class devices owned by sysfs */
+ for (i = 0; i < chip->ngpio; i++) {
+ desc = &gpio_desc[chip->base + i];
+ if (test_and_clear_bit(FLAG_SYSFS, &desc->flags))
+ gpio_free(chip->base + i);
+ }
}
static int __init gpiolib_sysfs_init(void)
? (1 << FLAG_IS_OUT)
: 0;
}
- }
- of_gpiochip_add(chip);
+ of_gpiochip_add(chip);
+ }
unlock:
spin_unlock_irqrestore(&gpio_lock, flags);
goto fail;
status = gpiochip_export(chip);
- if (status)
+ if (status) {
+ of_gpiochip_remove(chip);
goto fail;
+ }
return 0;
fail:
int status = 0;
unsigned id;
+ gpiochip_unexport(chip);
+
spin_lock_irqsave(&gpio_lock, flags);
of_gpiochip_remove(chip);
spin_unlock_irqrestore(&gpio_lock, flags);
- if (status == 0)
- gpiochip_unexport(chip);
-
return status;
}
EXPORT_SYMBOL_GPL(gpiochip_remove);