HID: Add driver to fix Speedlink VAD Cezanne support
Speedlink VAD Cezanne have a hardware bug that makes the cursor "jump" from one
place to another every now and then. The issue are relative motion events
erroneously reported by the device, each having a distance value of +256. This
256 can in fact never occur due to real motion, therefore those events can
safely be ignored. The driver also drops useless EV_REL events with a value of
0, that the device sends every time it sends an "real" EV_REL or EV_KEY event.
Signed-off-by: Stefan Kriwanek <mail@stefankriwanek.de>
Signed-off-by: Jiri Kosina <jkosina@suse.cz>
diff --git a/drivers/hid/hid-speedlink.c b/drivers/hid/hid-speedlink.c
new file mode 100644
index 0000000..6020137
--- /dev/null
+++ b/drivers/hid/hid-speedlink.c
@@ -0,0 +1,89 @@
+/*
+ * HID driver for Speedlink Vicious and Divine Cezanne (USB mouse).
+ * Fixes "jumpy" cursor and removes nonexistent keyboard LEDS from
+ * the HID descriptor.
+ *
+ * Copyright (c) 2011 Stefan Kriwanek <mail@stefankriwanek.de>
+ */
+
+/*
+ * This program is free software; you can redistribute it and/or modify it
+ * under the terms of the GNU General Public License as published by the Free
+ * Software Foundation; either version 2 of the License, or (at your option)
+ * any later version.
+ */
+
+#include <linux/device.h>
+#include <linux/hid.h>
+#include <linux/module.h>
+#include <linux/usb.h>
+
+#include "hid-ids.h"
+#include "usbhid/usbhid.h"
+
+static const struct hid_device_id speedlink_devices[] = {
+ { HID_USB_DEVICE(USB_VENDOR_ID_X_TENSIONS, USB_DEVICE_ID_SPEEDLINK_VAD_CEZANNE)},
+ { }
+};
+
+static int speedlink_input_mapping(struct hid_device *hdev,
+ struct hid_input *hi,
+ struct hid_field *field, struct hid_usage *usage,
+ unsigned long **bit, int *max)
+{
+ /*
+ * The Cezanne mouse has a second "keyboard" USB endpoint for it is
+ * able to map keyboard events to the button presses.
+ * It sends a standard keyboard report descriptor, though, whose
+ * LEDs we ignore.
+ */
+ switch (usage->hid & HID_USAGE_PAGE) {
+ case HID_UP_LED:
+ return -1;
+ }
+ return 0;
+}
+
+static int speedlink_event(struct hid_device *hdev, struct hid_field *field,
+ struct hid_usage *usage, __s32 value)
+{
+ /* No other conditions due to usage_table. */
+ /* Fix "jumpy" cursor (invalid events sent by device). */
+ if (value == 256)
+ return 1;
+ /* Drop useless distance 0 events (on button clicks etc.) as well */
+ if (value == 0)
+ return 1;
+
+ return 0;
+}
+
+MODULE_DEVICE_TABLE(hid, speedlink_devices);
+
+static const struct hid_usage_id speedlink_grabbed_usages[] = {
+ { HID_GD_X, EV_REL, 0 },
+ { HID_GD_Y, EV_REL, 1 },
+ { HID_ANY_ID - 1, HID_ANY_ID - 1, HID_ANY_ID - 1}
+};
+
+static struct hid_driver speedlink_driver = {
+ .name = "speedlink",
+ .id_table = speedlink_devices,
+ .usage_table = speedlink_grabbed_usages,
+ .input_mapping = speedlink_input_mapping,
+ .event = speedlink_event,
+};
+
+static int __init speedlink_init(void)
+{
+ return hid_register_driver(&speedlink_driver);
+}
+
+static void __exit speedlink_exit(void)
+{
+ hid_unregister_driver(&speedlink_driver);
+}
+
+module_init(speedlink_init);
+module_exit(speedlink_exit);
+MODULE_LICENSE("GPL");