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authorFrank Yang <puilp0502@gmail.com>2020-08-20 21:16:50 +0300
committerJiri Kosina <jkosina@suse.cz>2020-10-23 14:23:44 +0300
commit652f3d00de523a17b0cebe7b90debccf13aa8c31 (patch)
tree67ea2fbd48bbc54f38728d4540c1747a9c6077de /drivers/hid/hid-cypress.c
parent3c785a06dee99501a17f8e8cf29b2b7e3f1e94ea (diff)
downloadlinux-652f3d00de523a17b0cebe7b90debccf13aa8c31.tar.xz
HID: cypress: Support Varmilo Keyboards' media hotkeys
The Varmilo VA104M Keyboard (04b4:07b1, reported as Varmilo Z104M) exposes media control hotkeys as a USB HID consumer control device, but these keys do not work in the current (5.8-rc1) kernel due to the incorrect HID report descriptor. Fix the problem by modifying the internal HID report descriptor. More specifically, the keyboard report descriptor specifies the logical boundary as 572~10754 (0x023c ~ 0x2a02) while the usage boundary is specified as 0~10754 (0x00 ~ 0x2a02). This results in an incorrect interpretation of input reports, causing inputs to be ignored. By setting the Logical Minimum to zero, we align the logical boundary with the Usage ID boundary. Some notes: * There seem to be multiple variants of the VA104M keyboard. This patch specifically targets 04b4:07b1 variant. * The device works out-of-the-box on Windows platform with the generic consumer control device driver (hidserv.inf). This suggests that Windows either ignores the Logical Minimum/Logical Maximum or interprets the Usage ID assignment differently from the linux implementation; Maybe there are other devices out there that only works on Windows due to this problem? Signed-off-by: Frank Yang <puilp0502@gmail.com> Signed-off-by: Jiri Kosina <jkosina@suse.cz>
Diffstat (limited to 'drivers/hid/hid-cypress.c')
-rw-r--r--drivers/hid/hid-cypress.c44
1 files changed, 39 insertions, 5 deletions
diff --git a/drivers/hid/hid-cypress.c b/drivers/hid/hid-cypress.c
index a50ba4a4a1d7..b88f889b3932 100644
--- a/drivers/hid/hid-cypress.c
+++ b/drivers/hid/hid-cypress.c
@@ -23,19 +23,17 @@
#define CP_2WHEEL_MOUSE_HACK 0x02
#define CP_2WHEEL_MOUSE_HACK_ON 0x04
+#define VA_INVAL_LOGICAL_BOUNDARY 0x08
+
/*
* Some USB barcode readers from cypress have usage min and usage max in
* the wrong order
*/
-static __u8 *cp_report_fixup(struct hid_device *hdev, __u8 *rdesc,
+static __u8 *cp_rdesc_fixup(struct hid_device *hdev, __u8 *rdesc,
unsigned int *rsize)
{
- unsigned long quirks = (unsigned long)hid_get_drvdata(hdev);
unsigned int i;
- if (!(quirks & CP_RDESC_SWAPPED_MIN_MAX))
- return rdesc;
-
if (*rsize < 4)
return rdesc;
@@ -48,6 +46,40 @@ static __u8 *cp_report_fixup(struct hid_device *hdev, __u8 *rdesc,
return rdesc;
}
+static __u8 *va_logical_boundary_fixup(struct hid_device *hdev, __u8 *rdesc,
+ unsigned int *rsize)
+{
+ /*
+ * Varmilo VA104M (with VID Cypress and device ID 07B1) incorrectly
+ * reports Logical Minimum of its Consumer Control device as 572
+ * (0x02 0x3c). Fix this by setting its Logical Minimum to zero.
+ */
+ if (*rsize == 25 &&
+ rdesc[0] == 0x05 && rdesc[1] == 0x0c &&
+ rdesc[2] == 0x09 && rdesc[3] == 0x01 &&
+ rdesc[6] == 0x19 && rdesc[7] == 0x00 &&
+ rdesc[11] == 0x16 && rdesc[12] == 0x3c && rdesc[13] == 0x02) {
+ hid_info(hdev,
+ "fixing up varmilo VA104M consumer control report descriptor\n");
+ rdesc[12] = 0x00;
+ rdesc[13] = 0x00;
+ }
+ return rdesc;
+}
+
+static __u8 *cp_report_fixup(struct hid_device *hdev, __u8 *rdesc,
+ unsigned int *rsize)
+{
+ unsigned long quirks = (unsigned long)hid_get_drvdata(hdev);
+
+ if (quirks & CP_RDESC_SWAPPED_MIN_MAX)
+ rdesc = cp_rdesc_fixup(hdev, rdesc, rsize);
+ if (quirks & VA_INVAL_LOGICAL_BOUNDARY)
+ rdesc = va_logical_boundary_fixup(hdev, rdesc, rsize);
+
+ return rdesc;
+}
+
static int cp_input_mapped(struct hid_device *hdev, struct hid_input *hi,
struct hid_field *field, struct hid_usage *usage,
unsigned long **bit, int *max)
@@ -128,6 +160,8 @@ static const struct hid_device_id cp_devices[] = {
.driver_data = CP_RDESC_SWAPPED_MIN_MAX },
{ HID_USB_DEVICE(USB_VENDOR_ID_CYPRESS, USB_DEVICE_ID_CYPRESS_MOUSE),
.driver_data = CP_2WHEEL_MOUSE_HACK },
+ { HID_USB_DEVICE(USB_VENDOR_ID_CYPRESS, USB_DEVICE_ID_CYPRESS_VARMILO_VA104M_07B1),
+ .driver_data = VA_INVAL_LOGICAL_BOUNDARY },
{ }
};
MODULE_DEVICE_TABLE(hid, cp_devices);