diff options
Diffstat (limited to 'drivers/hid/hid-core.c')
| -rw-r--r-- | drivers/hid/hid-core.c | 23 |
1 files changed, 23 insertions, 0 deletions
diff --git a/drivers/hid/hid-core.c b/drivers/hid/hid-core.c index 3942ee61bd1c..402ad974b31c 100644 --- a/drivers/hid/hid-core.c +++ b/drivers/hid/hid-core.c @@ -1939,6 +1939,29 @@ static int hid_bus_match(struct device *dev, struct device_driver *drv) return hid_match_device(hdev, hdrv) != NULL; } +/** + * hid_compare_device_paths - check if both devices share the same path + * @hdev_a: hid device + * @hdev_b: hid device + * @separator: char to use as separator + * + * Check if two devices share the same path up to the last occurrence of + * the separator char. Both paths must exist (i.e., zero-length paths + * don't match). + */ +bool hid_compare_device_paths(struct hid_device *hdev_a, + struct hid_device *hdev_b, char separator) +{ + int n1 = strrchr(hdev_a->phys, separator) - hdev_a->phys; + int n2 = strrchr(hdev_b->phys, separator) - hdev_b->phys; + + if (n1 != n2 || n1 <= 0 || n2 <= 0) + return false; + + return !strncmp(hdev_a->phys, hdev_b->phys, n1); +} +EXPORT_SYMBOL_GPL(hid_compare_device_paths); + static int hid_device_probe(struct device *dev) { struct hid_driver *hdrv = to_hid_driver(dev->driver); |