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authorDaniel M. Lambea <dmlambea@gmail.com>2018-07-18 00:35:36 +0300
committerJiri Kosina <jkosina@suse.cz>2018-07-23 12:35:05 +0300
commit1a8861f117608e269647fb09658ce77bd5899d42 (patch)
tree6ebd9e26f1bd3278c19f22f45ea96dcc6ff24153 /drivers/hid/hid-core.c
parent092150a25cb7bd6a79aa00bb1ad131063f58073d (diff)
downloadlinux-1a8861f117608e269647fb09658ce77bd5899d42.tar.xz
HID: cougar: make compare_device_paths reusable
The function compare_device_paths from wacom_sys.c is generic and useful for other drivers. Move the function to hid-core and rename it as hid_compare_device_paths. Signed-off-by: Daniel M. Lambea <dmlambea@gmail.com> Reviewed-by: Benjamin Tissoires <benjamin.tissoires@redhat.com> Signed-off-by: Jiri Kosina <jkosina@suse.cz>
Diffstat (limited to 'drivers/hid/hid-core.c')
-rw-r--r--drivers/hid/hid-core.c23
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);