Input: HID - add a quirk for the Logitech USB Receiver

Logitech USB Receiver (046d:c101) has two interfaces. The first one
contains fields from HID_UP_KEYBOARD and HID_UP_LED, and the other one
contains fields from HID_UP_CONSUMER and HID_UP_LOGIVENDOR. This device
is used with multiple wireless Logitech products, including UltraX Media
Remote.

All fields on both interfaces are either keys or leds. All fields in the
first interface are marked as Absolute, while the fields in the second
interface are marked as Relative. Marking the keys as relative causes
hidinput_hid_event() to send release events right after key press
events.

The device has EV_REP set, so the userspace expects the device to send
repeat events if a key is held down. However, as hidinput_hid_event()
sends release events immediately, repeat events are not sent at all. In
fact, the userspace has no way of knowing if a key is being held down.

Fix this by adding a quirk for 046d:c101 which changes relative keys to
absolute ones.

Signed-off-by: Anssi Hannula <anssi.hannula@gmail.com>
Signed-off-by: Dmitry Torokhov <dtor@mail.ru>

drivers/usb/input/hid-core.c

@@ -1643,6 +1643,9 @@ void hid_init_reports(struct hid_device *hid)
 #define USB_VENDOR_ID_AIRCABLE		0x16CA
 #define USB_DEVICE_ID_AIRCABLE1		0x1502
 
+#define USB_VENDOR_ID_LOGITECH		0x046d
+#define USB_DEVICE_ID_LOGITECH_USB_RECEIVER	0xc101
+
 /*
  * Alphabetically sorted blacklist by quirk type.
  */
@@ -1811,7 +1814,9 @@ static const struct hid_blacklist {
 	{ USB_VENDOR_ID_PANJIT, 0x0004, HID_QUIRK_IGNORE },
 
 	{ USB_VENDOR_ID_TURBOX, USB_DEVICE_ID_TURBOX_KEYBOARD, HID_QUIRK_NOGET },
-	
+
+	{ USB_VENDOR_ID_LOGITECH, USB_DEVICE_ID_LOGITECH_USB_RECEIVER, HID_QUIRK_BAD_RELATIVE_KEYS },
+
 	{ 0, 0 }
 };
 

drivers/usb/input/hid-input.c

@@ -564,6 +564,10 @@ static void hidinput_configure_usage(struct hid_input *hidinput, struct hid_fiel
 		|| ((device->quirks & HID_QUIRK_2WHEEL_MOUSE_HACK_7) && (usage->hid == 0x00090007)))
 		goto ignore;
 
+	if ((device->quirks & HID_QUIRK_BAD_RELATIVE_KEYS) &&
+	    usage->type == EV_KEY && (field->flags & HID_MAIN_ITEM_RELATIVE))
+		field->flags &= ~HID_MAIN_ITEM_RELATIVE;
+
 	set_bit(usage->type, input->evbit);
 
 	while (usage->code <= max && test_and_set_bit(usage->code, bit))

drivers/usb/input/hid.h

@@ -260,6 +260,7 @@ struct hid_item {
 #define HID_QUIRK_POWERBOOK_HAS_FN		0x00001000
 #define HID_QUIRK_POWERBOOK_FN_ON		0x00002000
 #define HID_QUIRK_INVERT_HWHEEL			0x00004000
+#define HID_QUIRK_BAD_RELATIVE_KEYS		0x00008000
 
 /*
  * This is the global environment of the parser. This information is