/*
* HID driver for Huion devices not fully compliant with HID standard
*
* Copyright (c) 2013 Martin Rusko
* Copyright (c) 2014 Nikolai Kondrashov
*/
/*
* 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 <asm/unaligned.h>
#include "usbhid/usbhid.h"
#include "hid-ids.h"
/* Report descriptor template placeholder head */
#define HUION_PH_HEAD 0xFE, 0xED, 0x1D
/* Report descriptor template placeholder IDs */
enum huion_ph_id {
HUION_PH_ID_X_LM,
HUION_PH_ID_X_PM,
HUION_PH_ID_Y_LM,
HUION_PH_ID_Y_PM,
HUION_PH_ID_PRESSURE_LM,
HUION_PH_ID_NUM
};
/* Report descriptor template placeholder */
#define HUION_PH(_ID) HUION_PH_HEAD, HUION_PH_ID_##_ID
/* Fixed report descriptor template */
static const __u8 huion_tablet_rdesc_template[] = {
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), */
0x27, HUION_PH(X_LM), /* Logical Maximum (PLACEHOLDER), */
0x47, HUION_PH(X_PM), /* Physical Maximum (PLACEHOLDER), */
0x81, 0x02, /* Input (Variable), */
0x09, 0x31, /* Usage (Y), */
0x27, HUION_PH(Y_LM), /* Logical Maximum (PLACEHOLDER), */
0x47, HUION_PH(Y_PM), /* Physical Maximum (PLACEHOLDER), */
0x81, 0x02, /* Input (Variable), */
0xB4, /* Pop, */
0x09, 0x30, /* Usage (Tip Pressure), */
0x27,
HUION_PH(PRESSURE_LM), /* Logical Maximum (PLACEHOLDER), */
0x81, 0x02, /* Input (Variable), */
0xC0, /* End Collection, */
0xC0 /* End Collection */
};
/* Parameter indices */
enum huion_prm {
HUION_PRM_X_LM = 1,
HUION_PRM_Y_LM = 2,
HUION_PRM_PRESSURE_LM = 4,
HUION_PRM_RESOLUTION = 5,
HUION_PRM_NUM
};
/* Driver data */
struct huion_drvdata {
__u8 *rdesc;
unsigned int rsize;
};
static __u8 *huion_report_fixup(struct hid_device *hdev, __u8 *rdesc,
unsigned int *rsize)
{
struct huion_drvdata *drvdata = hid_get_drvdata(hdev);
switch (hdev->product) {
case USB_DEVICE_ID_HUION_TABLET:
if (drvdata->rdesc != NULL) {
rdesc = drvdata->rdesc;
*rsize = drvdata->rsize;
}
break;
}
return rdesc;
}
/**
* Enable fully-functional tablet mode and determine device parameters.
*
* @hdev: HID device
*/
static int huion_tablet_enable(struct hid_device *hdev)
{
int rc;
struct usb_device *usb_dev = hid_to_usb_dev(hdev);
struct huion_drvdata *drvdata = hid_get_drvdata(hdev);
__le16 *buf = NULL;
size_t len;
s32 params[HUION_PH_ID_NUM];
s32 resolution;
__u8 *p;
s32 v;
/*
* Read string descriptor containing tablet parameters. The specific
* string descriptor and data were discovered by sniffing the Windows
* driver traffic.
* NOTE: This enables fully-functional tablet mode.
*/
len = HUION_PRM_NUM * sizeof(*buf);
buf = kmalloc(len, GFP_KERNEL);
if (buf == NULL) {
hid_err(hdev, "failed to allocate parameter buffer\n");
rc = -ENOMEM;
goto cleanup;
}
rc = usb_control_msg(usb_dev, usb_rcvctrlpipe(usb_dev, 0),
USB_REQ_GET_DESCRIPTOR, USB_DIR_IN,
(USB_DT_STRING << 8) + 0x64,
0x0409, buf, len,
USB_CTRL_GET_TIMEOUT);
if (rc == -EPIPE) {
hid_err(hdev, "device parameters not found\n");
rc = -ENODEV;
goto cleanup;
} else if (rc < 0) {
hid_err(hdev, "failed to get device parameters: %d\n", rc);
rc = -ENODEV;
goto cleanup;
} else if (rc != len) {
hid_err(hdev, "invalid device parameters\n");
rc = -ENODEV;
goto cleanup;
}
/* Extract device parameters */
params[HUION_PH_ID_X_LM] = le16_to_cpu(buf[HUION_PRM_X_LM]);
params[HUION_PH_ID_Y_LM] = le16_to_cpu(buf[HUION_PRM_Y_LM]);
params[HUION_PH_ID_PRESSURE_LM] =
le16_to_cpu(buf[HUION_PRM_PRESSURE_LM]);
resolution = le16_to_cpu(buf[HUION_PRM_RESOLUTION]);
if (resolution == 0) {
params[HUION_PH_ID_X_PM] = 0;
params[HUION_PH_ID_Y_PM] = 0;
} else {
params[HUION_PH_ID_X_PM] = params[HUION_PH_ID_X_LM] *
1000 / resolution;
params[HUION_PH_ID_Y_PM] = params[HUION_PH_ID_Y_LM] *
1000 / resolution;
}
/* Allocate fixed report descriptor */
drvdata->rdesc = devm_kmalloc(&hdev->dev,
sizeof(huion_tablet_rdesc_template),
GFP_KERNEL);
if (drvdata->rdesc == NULL) {
hid_err(hdev, "failed to allocate fixed rdesc\n");
rc = -ENOMEM;
goto cleanup;
}
drvdata->rsize = sizeof(huion_tablet_rdesc_template);
/* Format fixed report descriptor */
memcpy(drvdata->rdesc, huion_tablet_rdesc_template,
drvdata->rsize);
for (p = drvdata->rdesc;
p <= drvdata->rdesc + drvdata->rsize - 4;) {
if (p[0] == 0xFE && p[1] == 0xED && p[2] == 0x1D &&
p[3] < sizeof(params)) {
v = params[p[3]];
put_unaligned(cpu_to_le32(v), (s32 *)p);
p += 4;
} else {
p++;
}
}
rc = 0;
cleanup:
kfree(buf);
return rc;
}
static int huion_probe(struct hid_device *hdev, const struct hid_device_id *id)
{
int rc;
struct usb_interface *intf = to_usb_interface(hdev->dev.parent);
struct huion_drvdata *drvdata;
/* Allocate and assign driver data */
drvdata = devm_kzalloc(&hdev->dev, sizeof(*drvdata), GFP_KERNEL);
if (drvdata == NULL) {
hid_err(hdev, "failed to allocate driver data\n");
return -ENOMEM;
}
hid_set_drvdata(hdev, drvdata);
switch (id->product) {
case USB_DEVICE_ID_HUION_TABLET:
/* If this is the pen interface */
if (intf->cur_altsetting->desc.bInterfaceNumber == 0) {
rc = huion_tablet_enable(hdev);
if (rc) {
hid_err(hdev, "tablet enabling failed\n");
return rc;
}
}
break;
}
rc = hid_parse(hdev);
if (rc) {
hid_err(hdev, "parse failed\n");
return rc;
}
rc = hid_hw_start(hdev, HID_CONNECT_DEFAULT);
if (rc) {
hid_err(hdev, "hw start failed\n");
return rc;
}
return 0;
}
static int huion_raw_event(struct hid_device *hdev, struct hid_report *report,
u8 *data, int size)
{
struct usb_interface *intf = to_usb_interface(hdev->dev.parent);
/* If this is a pen input report */
if (intf->cur_altsetting->desc.bInterfaceNumber == 0 &&
report->type == HID_INPUT_REPORT &&
report->id == 0x07 && size >= 2)
/* Invert the in-range bit */
data[1] ^= 0x40;
return 0;
}
static const struct hid_device_id huion_devices[] = {
{ HID_USB_DEVICE(USB_VENDOR_ID_HUION, USB_DEVICE_ID_HUION_TABLET) },
{ HID_USB_DEVICE(USB_VENDOR_ID_UCLOGIC, USB_DEVICE_ID_HUION_TABLET) },
{ }
};
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");
