[PATCH 1/4] HID: i2c-hid: Use wVersionID for device version

[Daniel Schaefer <dhs@frame.work>]

Use wVersionID instead of bcdVersion for hid->version. Per the HID
over I2C Protocol Specification (Rev 1.0, Section 4.2), the HID
descriptor contains two version fields with distinct purposes:

  - bcdVersion: HID specification version (always 0x0100 for HID 1.0)
  - wVersionID: Device-specific version number

The current code incorrectly uses bcdVersion, which always reports
the HID spec version rather than the actual device/firmware version.
This change aligns I2C HID behavior with USB HID, which correctly
uses bcdDevice (the device version) for hid->version.

Currently wVersionID is not exposed to userspace at all. It is useful
because some firmwares use this as their firmware version. It's not
possible to check those device's firmware version on Linux, only
Windows.

Cc: Jiri Kosina <jikos@kernel.org>
Cc: Benjamin Tissoires <bentiss@kernel.org>
Cc: linux-input@vger.kernel.org
Cc: linux@frame.work
Signed-off-by: Daniel Schaefer <dhs@frame.work>
---
 drivers/hid/i2c-hid/i2c-hid-core.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/drivers/hid/i2c-hid/i2c-hid-core.c b/drivers/hid/i2c-hid/i2c-hid-core.c
index 5a183af3d5c6..41327e32f359 100644
--- a/drivers/hid/i2c-hid/i2c-hid-core.c
+++ b/drivers/hid/i2c-hid/i2c-hid-core.c
@@ -1056,7 +1056,7 @@ static int __i2c_hid_core_probe(struct i2c_hid *ihid)
 		return ret;
 	}
 
-	hid->version = le16_to_cpu(ihid->hdesc.bcdVersion);
+	hid->version = le16_to_cpu(ihid->hdesc.wVersionID);
 	hid->vendor = le16_to_cpu(ihid->hdesc.wVendorID);
 	hid->product = le16_to_cpu(ihid->hdesc.wProductID);
 
-- 
2.52.0