diff options
Diffstat (limited to 'drivers/gpio/gpiolib.c')
| -rw-r--r-- | drivers/gpio/gpiolib.c | 34 |
1 files changed, 29 insertions, 5 deletions
diff --git a/drivers/gpio/gpiolib.c b/drivers/gpio/gpiolib.c index 40f2d7f69be2..182136d98b97 100644 --- a/drivers/gpio/gpiolib.c +++ b/drivers/gpio/gpiolib.c @@ -1158,8 +1158,19 @@ static void gpio_desc_to_lineinfo(struct gpio_desc *desc, struct gpioline_info *info) { struct gpio_chip *gc = desc->gdev->chip; + bool ok_for_pinctrl; unsigned long flags; + /* + * This function takes a mutex so we must check this before taking + * the spinlock. + * + * FIXME: find a non-racy way to retrieve this information. Maybe a + * lock common to both frameworks? + */ + ok_for_pinctrl = + pinctrl_gpio_can_use_line(gc->base + info->line_offset); + spin_lock_irqsave(&gpio_lock, flags); if (desc->name) { @@ -1186,7 +1197,7 @@ static void gpio_desc_to_lineinfo(struct gpio_desc *desc, test_bit(FLAG_USED_AS_IRQ, &desc->flags) || test_bit(FLAG_EXPORT, &desc->flags) || test_bit(FLAG_SYSFS, &desc->flags) || - !pinctrl_gpio_can_use_line(gc->base + info->line_offset)) + !ok_for_pinctrl) info->flags |= GPIOLINE_FLAG_KERNEL; if (test_bit(FLAG_IS_OUT, &desc->flags)) info->flags |= GPIOLINE_FLAG_IS_OUT; @@ -1227,6 +1238,7 @@ static long gpio_ioctl(struct file *filp, unsigned int cmd, unsigned long arg) void __user *ip = (void __user *)arg; struct gpio_desc *desc; __u32 offset; + int hwgpio; /* We fail any subsequent ioctl():s when the chip is gone */ if (!gc) @@ -1259,13 +1271,19 @@ static long gpio_ioctl(struct file *filp, unsigned int cmd, unsigned long arg) if (IS_ERR(desc)) return PTR_ERR(desc); + hwgpio = gpio_chip_hwgpio(desc); + + if (cmd == GPIO_GET_LINEINFO_WATCH_IOCTL && + test_bit(hwgpio, priv->watched_lines)) + return -EBUSY; + gpio_desc_to_lineinfo(desc, &lineinfo); if (copy_to_user(ip, &lineinfo, sizeof(lineinfo))) return -EFAULT; if (cmd == GPIO_GET_LINEINFO_WATCH_IOCTL) - set_bit(gpio_chip_hwgpio(desc), priv->watched_lines); + set_bit(hwgpio, priv->watched_lines); return 0; } else if (cmd == GPIO_GET_LINEHANDLE_IOCTL) { @@ -1280,7 +1298,12 @@ static long gpio_ioctl(struct file *filp, unsigned int cmd, unsigned long arg) if (IS_ERR(desc)) return PTR_ERR(desc); - clear_bit(gpio_chip_hwgpio(desc), priv->watched_lines); + hwgpio = gpio_chip_hwgpio(desc); + + if (!test_bit(hwgpio, priv->watched_lines)) + return -EBUSY; + + clear_bit(hwgpio, priv->watched_lines); return 0; } return -EINVAL; @@ -5289,8 +5312,9 @@ static int __init gpiolib_dev_init(void) gpiolib_initialized = true; gpiochip_setup_devs(); - if (IS_ENABLED(CONFIG_OF_DYNAMIC)) - WARN_ON(of_reconfig_notifier_register(&gpio_of_notifier)); +#if IS_ENABLED(CONFIG_OF_DYNAMIC) && IS_ENABLED(CONFIG_OF_GPIO) + WARN_ON(of_reconfig_notifier_register(&gpio_of_notifier)); +#endif /* CONFIG_OF_DYNAMIC && CONFIG_OF_GPIO */ return ret; } |