/*
* HID driver for Huion devices not fully compliant with HID standard
*
* Copyright (c) 2013 Martin Rusko
*/
/*
* 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 "usbhid/usbhid.h"
#include "hid-ids.h"
/* Original Huion 580 report descriptor size */
#define HUION_580_RDESC_ORIG_SIZE 177
/* Fixed Huion 580 report descriptor */
static __u8 huion_580_rdesc_fixed[] = {
0x05, 0x0D, /* Usage Page (Digitizer), */
0x09, 0x02, /* Usage (Pen), */
0xA1, 0x01, /* Collection (Application), */
0x85, 0x07, /* Report ID (7), */
0x09, 0x20, /* Usage (Stylus), */
0xA0, /* Collection (Physical), */
0x14, /* Logical Minimum (0), */
0x25, 0x01, /* Logical Maximum (1), */
0x75, 0x01, /* Report Size (1), */
0x09, 0x42, /* Usage (Tip Switch), */
0x09, 0x44, /* Usage (Barrel Switch), */
0x09, 0x46, /* Usage (Tablet Pick), */
0x95, 0x03, /* Report Count (3), */
0x81, 0x02, /* Input (Variable), */
0x95, 0x03, /* Report Count (3), */
0x81, 0x03, /* Input (Constant, Variable), */
0x09, 0x32, /* Usage (In Range), */
0x95, 0x01, /* Report Count (1), */
0x81, 0x02, /* Input (Variable), */
0x95, 0x01, /* Report Count (1), */
0x81, 0x03, /* Input (Constant, Variable), */
0x75, 0x10, /* Report Size (16), */
0x95, 0x01, /* Report Count (1), */
0xA4, /* Push, */
0x05, 0x01, /* Usage Page (Desktop), */
0x65, 0x13, /* Unit (Inch), */
0x55, 0xFD, /* Unit Exponent (-3), */
0x34, /* Physical Minimum (0), */
0x09, 0x30, /* Usage (X), */
0x46, 0x40, 0x1F, /* Physical Maximum (8000), */
0x26, 0x00, 0x7D, /* Logical Maximum (32000), */
0x81, 0x02, /* Input (Variable), */
0x09, 0x31, /* Usage (Y), */
0x46, 0x88, 0x13, /* Physical Maximum (5000), */
0x26, 0x20, 0x4E, /* Logical Maximum (20000), */
0x81, 0x02, /* Input (Variable), */
0xB4, /* Pop, */
0x09, 0x30, /* Usage (Tip Pressure), */
0x26, 0xFF, 0x07, /* Logical Maximum (2047), */
0x81, 0x02, /* Input (Variable), */
0xC0, /* End Collection, */
0xC0 /* End Collection */
};
static __u8 *huion_report_fixup(struct hid_device *hdev, __u8 *rdesc,
unsigned int *rsize)
{
switch (hdev->product) {
case USB_DEVICE_ID_HUION_580:
if (*rsize == HUION_580_RDESC_ORIG_SIZE) {
rdesc = huion_580_rdesc_fixed;
*rsize = sizeof(huion_580_rdesc_fixed);
}
break;
}
return rdesc;
}
/**
* Enable fully-functional tablet mode by reading special string
* descriptor.
*
* @hdev: HID device
*
* The specific string descriptor and data were discovered by sniffing
* the Windows driver traffic.
*/
static int huion_tablet_enable(struct hid_device *hdev)
{
int rc;
char buf[22];
rc = usb_string(hid_to_usb_dev(hdev), 0x64, buf, sizeof(buf));
if (rc < 0)
return rc;
return 0;
}
static int huion_probe(struct hid_device *hdev, const struct hid_device_id *id)
{
int ret;
struct usb_interface *intf = to_usb_interface(hdev->dev.parent);
/* Ignore interfaces 1 (mouse) and 2 (keyboard) for Huion 580 tablet,
* as they are not used
*/
switch (id->product) {
case USB_DEVICE_ID_HUION_580:
if (intf->cur_altsetting->desc.bInterfaceNumber != 0x00)
return -ENODEV;
break;
}
ret = hid_parse(hdev);
if (ret) {
hid_err(hdev, "parse failed\n");
goto err;
}
ret = hid_hw_start(hdev, HID_CONNECT_DEFAULT);
if (ret) {
hid_err(hdev, "hw start failed\n");
goto err;
}
switch (id->product) {
case USB_DEVICE_ID_HUION_580:
ret = huion_tablet_enable(hdev);
if (ret) {
hid_err(hdev, "tablet enabling failed\n");
goto enabling_err;
}
break;
}
return 0;
enabling_err:
hid_hw_stop(hdev);
err:
return ret;
}
static int huion_raw_event(struct hid_device *hdev, struct hid_report *report,
u8 *data, int size)
{
/* If this is a pen input report then invert the in-range bit */
if (report->type == HID_INPUT_REPORT && report->id == 0x07 && size >= 2)
data[1] ^= 0x40;
return 0;
}
static const struct hid_device_id huion_devices[] = {
{ HID_USB_DEVICE(USB_VENDOR_ID_HUION, USB_DEVICE_ID_HUION_580) },
{ }
};
MODULE_DEVICE_TABLE(hid, huion_devices);
static struct hid_driver huion_driver = {
.name = "huion",
.id_table = huion_devices,
.probe = huion_probe,
.report_fixup = huion_report_fixup,
.raw_event = huion_raw_event,
};
module_hid_driver(huion_driver);
MODULE_AUTHOR("Martin Rusko");
MODULE_DESCRIPTION("Huion HID driver");
MODULE_LICENSE("GPL");
