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| author | Blaž Hrastnik <blaz@mxxn.io> | 2019-11-06 20:02:46 +0900 |
|---|---|---|
| committer | Greg Kroah-Hartman <gregkh@linuxfoundation.org> | 2020-01-04 13:40:57 +0100 |
| commit | 6deeb4874ad7bd4d1097eae062bdfa265a1e4212 (patch) | |
| tree | 49a888541ce80ca3840236e7eed87e2cdfe74141 /drivers/hid/hid-core.c | |
| parent | 116d44d11e2791de5751a69c1a7c8fa4fa63caf6 (diff) | |
HID: Improve Windows Precision Touchpad detection.
[ Upstream commit 2dbc6f113acd74c66b04bf49fb027efd830b1c5a ]
Per Microsoft spec, usage 0xC5 (page 0xFF) returns a blob containing
data used to verify the touchpad as a Windows Precision Touchpad.
0x85, REPORTID_PTPHQA, // REPORT_ID (PTPHQA)
0x09, 0xC5, // USAGE (Vendor Usage 0xC5)
0x15, 0x00, // LOGICAL_MINIMUM (0)
0x26, 0xff, 0x00, // LOGICAL_MAXIMUM (0xff)
0x75, 0x08, // REPORT_SIZE (8)
0x96, 0x00, 0x01, // REPORT_COUNT (0x100 (256))
0xb1, 0x02, // FEATURE (Data,Var,Abs)
However, some devices, namely Microsoft's Surface line of products
instead implement a "segmented device certification report" (usage 0xC6)
which returns the same report, but in smaller chunks.
0x06, 0x00, 0xff, // USAGE_PAGE (Vendor Defined)
0x85, REPORTID_PTPHQA, // REPORT_ID (PTPHQA)
0x09, 0xC6, // USAGE (Vendor usage for segment #)
0x25, 0x08, // LOGICAL_MAXIMUM (8)
0x75, 0x08, // REPORT_SIZE (8)
0x95, 0x01, // REPORT_COUNT (1)
0xb1, 0x02, // FEATURE (Data,Var,Abs)
0x09, 0xC7, // USAGE (Vendor Usage)
0x26, 0xff, 0x00, // LOGICAL_MAXIMUM (0xff)
0x95, 0x20, // REPORT_COUNT (32)
0xb1, 0x02, // FEATURE (Data,Var,Abs)
By expanding Win8 touchpad detection to also look for the segmented
report, all Surface touchpads are now properly recognized by
hid-multitouch.
Signed-off-by: Blaž Hrastnik <blaz@mxxn.io>
Signed-off-by: Benjamin Tissoires <benjamin.tissoires@redhat.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
Diffstat (limited to 'drivers/hid/hid-core.c')
| -rw-r--r-- | drivers/hid/hid-core.c | 4 |
1 files changed, 4 insertions, 0 deletions
diff --git a/drivers/hid/hid-core.c b/drivers/hid/hid-core.c index 42d1b350afd2..c89eb3c3965c 100644 --- a/drivers/hid/hid-core.c +++ b/drivers/hid/hid-core.c @@ -761,6 +761,10 @@ static void hid_scan_feature_usage(struct hid_parser *parser, u32 usage) if (usage == 0xff0000c5 && parser->global.report_count == 256 && parser->global.report_size == 8) parser->scan_flags |= HID_SCAN_FLAG_MT_WIN_8; + + if (usage == 0xff0000c6 && parser->global.report_count == 1 && + parser->global.report_size == 8) + parser->scan_flags |= HID_SCAN_FLAG_MT_WIN_8; } static void hid_scan_collection(struct hid_parser *parser, unsigned type) |