Merge tag 'v5.7-rc7' into devel

Linux 5.7-rc7

1 files changed, 29 insertions, 5 deletions

diff --git a/drivers/gpio/gpiolib.c b/drivers/gpio/gpiolib.c
index 449334732fbf..2e4aacbad8fe 100644
--- a/drivers/gpio/gpiolib.c
+++ b/drivers/gpio/gpiolib.c
@@ -1163,8 +1163,19 @@ 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) {
@@ -1191,7 +1202,7 @@ 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;
@@ -1232,6 +1243,7 @@ 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)
@@ -1264,13 +1276,19 @@ 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) {
@@ -1285,7 +1303,12 @@ 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;
@@ -5304,8 +5327,9 @@ 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;
 }