[PATCH AUTOSEL 4.14 4/8] HID: logitech-hidpp: Reconcile USB and Unifying serials

From: Sasha Levin
Date: Sat May 06 2023 - 20:56:10 EST


From: Bastien Nocera <hadess@xxxxxxxxxx>

[ Upstream commit 5b3691d15e04b6d5a32c915577b8dbc5cfb56382 ]

Now that USB HID++ devices can gather a serial number that matches the
one that would be gathered when connected through a Unifying receiver,
remove the last difference by dropping the product ID as devices
usually have different product IDs when connected through USB or
Unifying.

For example, on the serials on a G903 wired/wireless mouse:
- Unifying before patch: 4067-e8-ce-cd-45
- USB before patch: c086-e8-ce-cd-45
- Unifying and USB after patch: e8-ce-cd-45

Signed-off-by: Bastien Nocera <hadess@xxxxxxxxxx>
Link: https://lore.kernel.org/r/20230302130117.3975-2-hadess@xxxxxxxxxx
Signed-off-by: Benjamin Tissoires <benjamin.tissoires@xxxxxxxxxx>
Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx>
---
drivers/hid/hid-logitech-hidpp.c | 6 ++----
1 file changed, 2 insertions(+), 4 deletions(-)

diff --git a/drivers/hid/hid-logitech-hidpp.c b/drivers/hid/hid-logitech-hidpp.c
index e2db4731eb825..1588508b3e7b7 100644
--- a/drivers/hid/hid-logitech-hidpp.c
+++ b/drivers/hid/hid-logitech-hidpp.c
@@ -675,8 +675,7 @@ static int hidpp_unifying_init(struct hidpp_device *hidpp)
if (ret)
return ret;

- snprintf(hdev->uniq, sizeof(hdev->uniq), "%04x-%4phD",
- hdev->product, &serial);
+ snprintf(hdev->uniq, sizeof(hdev->uniq), "%4phD", &serial);
dbg_hid("HID++ Unifying: Got serial: %s\n", hdev->uniq);

name = hidpp_unifying_get_name(hidpp);
@@ -819,8 +818,7 @@ static int hidpp_serial_init(struct hidpp_device *hidpp)
if (ret)
return ret;

- snprintf(hdev->uniq, sizeof(hdev->uniq), "%04x-%4phD",
- hdev->product, &serial);
+ snprintf(hdev->uniq, sizeof(hdev->uniq), "%4phD", &serial);
dbg_hid("HID++ DeviceInformation: Got serial: %s\n", hdev->uniq);

return 0;
--
2.39.2