4.19-stable review patch. If anyone has any objections, please let me know.
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From: Benjamin Tissoires benjamin.tissoires@redhat.com
[ Upstream commit 1e839143d674603b0bbbc4c513bca35404967dbc ]
This unique identifier is currently used only for ensuring uniqueness in sysfs. However, this could be handful for userspace to refer to a specific hid_device by this id.
2 use cases are in my mind: LEDs (and their naming convention), and HID-BPF.
Reviewed-by: Greg Kroah-Hartman gregkh@linuxfoundation.org Signed-off-by: Benjamin Tissoires benjamin.tissoires@redhat.com Link: https://lore.kernel.org/r/20220902132938.2409206-9-benjamin.tissoires@redhat... Stable-dep-of: fc43e9c857b7 ("HID: fix HID device resource race between HID core and debugging support") Signed-off-by: Sasha Levin sashal@kernel.org --- drivers/hid/hid-core.c | 4 +++- include/linux/hid.h | 2 ++ 2 files changed, 5 insertions(+), 1 deletion(-)
diff --git a/drivers/hid/hid-core.c b/drivers/hid/hid-core.c index c8d687f795caa..99eb26bcb1dd3 100644 --- a/drivers/hid/hid-core.c +++ b/drivers/hid/hid-core.c @@ -2259,10 +2259,12 @@ int hid_add_device(struct hid_device *hdev) hid_warn(hdev, "bad device descriptor (%d)\n", ret); }
+ hdev->id = atomic_inc_return(&id); + /* XXX hack, any other cleaner solution after the driver core * is converted to allow more than 20 bytes as the device name? */ dev_set_name(&hdev->dev, "%04X:%04X:%04X.%04X", hdev->bus, - hdev->vendor, hdev->product, atomic_inc_return(&id)); + hdev->vendor, hdev->product, hdev->id);
hid_debug_register(hdev, dev_name(&hdev->dev)); ret = device_add(&hdev->dev); diff --git a/include/linux/hid.h b/include/linux/hid.h index 79c6c3b4e0044..10b41b2b20857 100644 --- a/include/linux/hid.h +++ b/include/linux/hid.h @@ -625,6 +625,8 @@ struct hid_device { /* device report descriptor */ struct list_head debug_list; spinlock_t debug_list_lock; wait_queue_head_t debug_wait; + + unsigned int id; /* system unique id */ };
#define to_hid_device(pdev) \