323 lines
9.2 KiB
C
323 lines
9.2 KiB
C
|
// SPDX-License-Identifier: GPL-2.0-only
|
||
|
/*
|
||
|
* Copyright (c) 2021 Hans de Goede <hdegoede@redhat.com>
|
||
|
*
|
||
|
* Driver for the LetSketch / VSON WP9620N drawing tablet.
|
||
|
* This drawing tablet is also sold under other brand names such as Case U,
|
||
|
* presumably this driver will work for all of them. But it has only been
|
||
|
* tested with a LetSketch WP9620N model.
|
||
|
*
|
||
|
* These tablets also work without a special HID driver, but then only part
|
||
|
* of the active area works and both the pad and stylus buttons are hardwired
|
||
|
* to special key-combos. E.g. the 2 stylus buttons send right mouse clicks /
|
||
|
* resp. "e" key presses.
|
||
|
*
|
||
|
* This device has 4 USB interfaces:
|
||
|
*
|
||
|
* Interface 0 EP 0x81 bootclass mouse, rdesc len 18, report id 0x08,
|
||
|
* Application(ff00.0001)
|
||
|
* This interface sends raw event input reports in a custom format, but only
|
||
|
* after doing the special dance from letsketch_probe(). After enabling this
|
||
|
* interface the other 3 interfaces are disabled.
|
||
|
*
|
||
|
* Interface 1 EP 0x82 bootclass mouse, rdesc len 83, report id 0x0a, Tablet
|
||
|
* This interface sends absolute events for the pen, including pressure,
|
||
|
* but only for some part of the active area due to special "aspect ratio"
|
||
|
* correction and only half by default since it assumes it will be used
|
||
|
* with a phone in portraid mode, while using the tablet in landscape mode.
|
||
|
* Also stylus + pad button events are not reported here.
|
||
|
*
|
||
|
* Interface 2 EP 0x83 bootclass keybd, rdesc len 64, report id none, Std Kbd
|
||
|
* This interfaces send various hard-coded key-combos for the pad buttons
|
||
|
* and "e" keypresses for the 2nd stylus button
|
||
|
*
|
||
|
* Interface 3 EP 0x84 bootclass mouse, rdesc len 75, report id 0x01, Std Mouse
|
||
|
* This reports right-click mouse-button events for the 1st stylus button
|
||
|
*/
|
||
|
#include <linux/device.h>
|
||
|
#include <linux/input.h>
|
||
|
#include <linux/hid.h>
|
||
|
#include <linux/module.h>
|
||
|
#include <linux/timer.h>
|
||
|
#include <linux/usb.h>
|
||
|
|
||
|
#include <asm/unaligned.h>
|
||
|
|
||
|
#include "hid-ids.h"
|
||
|
|
||
|
#define LETSKETCH_RAW_IF 0
|
||
|
|
||
|
#define LETSKETCH_RAW_DATA_LEN 12
|
||
|
#define LETSKETCH_RAW_REPORT_ID 8
|
||
|
|
||
|
#define LETSKETCH_PAD_BUTTONS 5
|
||
|
|
||
|
#define LETSKETCH_INFO_STR_IDX_BEGIN 0xc8
|
||
|
#define LETSKETCH_INFO_STR_IDX_END 0xca
|
||
|
|
||
|
#define LETSKETCH_GET_STRING_RETRIES 5
|
||
|
|
||
|
struct letsketch_data {
|
||
|
struct hid_device *hdev;
|
||
|
struct input_dev *input_tablet;
|
||
|
struct input_dev *input_tablet_pad;
|
||
|
struct timer_list inrange_timer;
|
||
|
};
|
||
|
|
||
|
static int letsketch_open(struct input_dev *dev)
|
||
|
{
|
||
|
struct letsketch_data *data = input_get_drvdata(dev);
|
||
|
|
||
|
return hid_hw_open(data->hdev);
|
||
|
}
|
||
|
|
||
|
static void letsketch_close(struct input_dev *dev)
|
||
|
{
|
||
|
struct letsketch_data *data = input_get_drvdata(dev);
|
||
|
|
||
|
hid_hw_close(data->hdev);
|
||
|
}
|
||
|
|
||
|
static struct input_dev *letsketch_alloc_input_dev(struct letsketch_data *data)
|
||
|
{
|
||
|
struct input_dev *input;
|
||
|
|
||
|
input = devm_input_allocate_device(&data->hdev->dev);
|
||
|
if (!input)
|
||
|
return NULL;
|
||
|
|
||
|
input->id.bustype = data->hdev->bus;
|
||
|
input->id.vendor = data->hdev->vendor;
|
||
|
input->id.product = data->hdev->product;
|
||
|
input->id.version = data->hdev->bus;
|
||
|
input->phys = data->hdev->phys;
|
||
|
input->uniq = data->hdev->uniq;
|
||
|
input->open = letsketch_open;
|
||
|
input->close = letsketch_close;
|
||
|
|
||
|
input_set_drvdata(input, data);
|
||
|
|
||
|
return input;
|
||
|
}
|
||
|
|
||
|
static int letsketch_setup_input_tablet(struct letsketch_data *data)
|
||
|
{
|
||
|
struct input_dev *input;
|
||
|
|
||
|
input = letsketch_alloc_input_dev(data);
|
||
|
if (!input)
|
||
|
return -ENOMEM;
|
||
|
|
||
|
input_set_abs_params(input, ABS_X, 0, 50800, 0, 0);
|
||
|
input_set_abs_params(input, ABS_Y, 0, 31750, 0, 0);
|
||
|
input_set_abs_params(input, ABS_PRESSURE, 0, 8192, 0, 0);
|
||
|
input_abs_set_res(input, ABS_X, 240);
|
||
|
input_abs_set_res(input, ABS_Y, 225);
|
||
|
input_set_capability(input, EV_KEY, BTN_TOUCH);
|
||
|
input_set_capability(input, EV_KEY, BTN_TOOL_PEN);
|
||
|
input_set_capability(input, EV_KEY, BTN_STYLUS);
|
||
|
input_set_capability(input, EV_KEY, BTN_STYLUS2);
|
||
|
|
||
|
/* All known brands selling this tablet use WP9620[N] as model name */
|
||
|
input->name = "WP9620 Tablet";
|
||
|
|
||
|
data->input_tablet = input;
|
||
|
|
||
|
return input_register_device(data->input_tablet);
|
||
|
}
|
||
|
|
||
|
static int letsketch_setup_input_tablet_pad(struct letsketch_data *data)
|
||
|
{
|
||
|
struct input_dev *input;
|
||
|
int i;
|
||
|
|
||
|
input = letsketch_alloc_input_dev(data);
|
||
|
if (!input)
|
||
|
return -ENOMEM;
|
||
|
|
||
|
for (i = 0; i < LETSKETCH_PAD_BUTTONS; i++)
|
||
|
input_set_capability(input, EV_KEY, BTN_0 + i);
|
||
|
|
||
|
/*
|
||
|
* These are never send on the pad input_dev, but must be set
|
||
|
* on the Pad to make udev / libwacom happy.
|
||
|
*/
|
||
|
input_set_abs_params(input, ABS_X, 0, 1, 0, 0);
|
||
|
input_set_abs_params(input, ABS_Y, 0, 1, 0, 0);
|
||
|
input_set_capability(input, EV_KEY, BTN_STYLUS);
|
||
|
|
||
|
input->name = "WP9620 Pad";
|
||
|
|
||
|
data->input_tablet_pad = input;
|
||
|
|
||
|
return input_register_device(data->input_tablet_pad);
|
||
|
}
|
||
|
|
||
|
static void letsketch_inrange_timeout(struct timer_list *t)
|
||
|
{
|
||
|
struct letsketch_data *data = from_timer(data, t, inrange_timer);
|
||
|
struct input_dev *input = data->input_tablet;
|
||
|
|
||
|
input_report_key(input, BTN_TOOL_PEN, 0);
|
||
|
input_sync(input);
|
||
|
}
|
||
|
|
||
|
static int letsketch_raw_event(struct hid_device *hdev,
|
||
|
struct hid_report *report,
|
||
|
u8 *raw_data, int size)
|
||
|
{
|
||
|
struct letsketch_data *data = hid_get_drvdata(hdev);
|
||
|
struct input_dev *input;
|
||
|
int i;
|
||
|
|
||
|
if (size != LETSKETCH_RAW_DATA_LEN || raw_data[0] != LETSKETCH_RAW_REPORT_ID)
|
||
|
return 0;
|
||
|
|
||
|
switch (raw_data[1] & 0xf0) {
|
||
|
case 0x80: /* Pen data */
|
||
|
input = data->input_tablet;
|
||
|
input_report_key(input, BTN_TOOL_PEN, 1);
|
||
|
input_report_key(input, BTN_TOUCH, raw_data[1] & 0x01);
|
||
|
input_report_key(input, BTN_STYLUS, raw_data[1] & 0x02);
|
||
|
input_report_key(input, BTN_STYLUS2, raw_data[1] & 0x04);
|
||
|
input_report_abs(input, ABS_X,
|
||
|
get_unaligned_le16(raw_data + 2));
|
||
|
input_report_abs(input, ABS_Y,
|
||
|
get_unaligned_le16(raw_data + 4));
|
||
|
input_report_abs(input, ABS_PRESSURE,
|
||
|
get_unaligned_le16(raw_data + 6));
|
||
|
/*
|
||
|
* There is no out of range event, so use a timer for this
|
||
|
* when in range we get an event approx. every 8 ms.
|
||
|
*/
|
||
|
mod_timer(&data->inrange_timer, jiffies + msecs_to_jiffies(100));
|
||
|
break;
|
||
|
case 0xe0: /* Pad data */
|
||
|
input = data->input_tablet_pad;
|
||
|
for (i = 0; i < LETSKETCH_PAD_BUTTONS; i++)
|
||
|
input_report_key(input, BTN_0 + i, raw_data[4] == (i + 1));
|
||
|
break;
|
||
|
default:
|
||
|
hid_warn(data->hdev, "Warning unknown data header: 0x%02x\n",
|
||
|
raw_data[0]);
|
||
|
return 0;
|
||
|
}
|
||
|
|
||
|
input_sync(input);
|
||
|
return 0;
|
||
|
}
|
||
|
|
||
|
/*
|
||
|
* The tablets magic handshake to put it in raw mode relies on getting
|
||
|
* string descriptors. But the firmware is buggy and does not like it if
|
||
|
* we do this too fast. Even if we go slow sometimes the usb_string() call
|
||
|
* fails. Ignore errors and retry it a couple of times if necessary.
|
||
|
*/
|
||
|
static int letsketch_get_string(struct usb_device *udev, int index, char *buf, int size)
|
||
|
{
|
||
|
int i, ret;
|
||
|
|
||
|
for (i = 0; i < LETSKETCH_GET_STRING_RETRIES; i++) {
|
||
|
usleep_range(5000, 7000);
|
||
|
ret = usb_string(udev, index, buf, size);
|
||
|
if (ret > 0)
|
||
|
return 0;
|
||
|
}
|
||
|
|
||
|
dev_err(&udev->dev, "Max retries (%d) exceeded reading string descriptor %d\n",
|
||
|
LETSKETCH_GET_STRING_RETRIES, index);
|
||
|
return ret ? ret : -EIO;
|
||
|
}
|
||
|
|
||
|
static int letsketch_probe(struct hid_device *hdev, const struct hid_device_id *id)
|
||
|
{
|
||
|
struct device *dev = &hdev->dev;
|
||
|
struct letsketch_data *data;
|
||
|
struct usb_interface *intf;
|
||
|
struct usb_device *udev;
|
||
|
char buf[256];
|
||
|
int i, ret;
|
||
|
|
||
|
if (!hid_is_using_ll_driver(hdev, &usb_hid_driver))
|
||
|
return -ENODEV;
|
||
|
|
||
|
intf = to_usb_interface(hdev->dev.parent);
|
||
|
if (intf->altsetting->desc.bInterfaceNumber != LETSKETCH_RAW_IF)
|
||
|
return -ENODEV; /* Ignore the other interfaces */
|
||
|
|
||
|
udev = interface_to_usbdev(intf);
|
||
|
|
||
|
/*
|
||
|
* Instead of using a set-feature request, or even a custom USB ctrl
|
||
|
* message the tablet needs this elaborate magic reading of USB
|
||
|
* string descriptors to kick it into raw mode. This is what the
|
||
|
* Windows drivers are seen doing in an USB trace under Windows.
|
||
|
*/
|
||
|
for (i = LETSKETCH_INFO_STR_IDX_BEGIN; i <= LETSKETCH_INFO_STR_IDX_END; i++) {
|
||
|
ret = letsketch_get_string(udev, i, buf, sizeof(buf));
|
||
|
if (ret)
|
||
|
return ret;
|
||
|
|
||
|
hid_info(hdev, "Device info: %s\n", buf);
|
||
|
}
|
||
|
|
||
|
for (i = 1; i <= 250; i++) {
|
||
|
ret = letsketch_get_string(udev, i, buf, sizeof(buf));
|
||
|
if (ret)
|
||
|
return ret;
|
||
|
}
|
||
|
|
||
|
ret = letsketch_get_string(udev, 0x64, buf, sizeof(buf));
|
||
|
if (ret)
|
||
|
return ret;
|
||
|
|
||
|
ret = letsketch_get_string(udev, LETSKETCH_INFO_STR_IDX_BEGIN, buf, sizeof(buf));
|
||
|
if (ret)
|
||
|
return ret;
|
||
|
|
||
|
/*
|
||
|
* The tablet should be in raw mode now, end with a final delay before
|
||
|
* doing further IO to the device.
|
||
|
*/
|
||
|
usleep_range(5000, 7000);
|
||
|
|
||
|
ret = hid_parse(hdev);
|
||
|
if (ret)
|
||
|
return ret;
|
||
|
|
||
|
data = devm_kzalloc(dev, sizeof(*data), GFP_KERNEL);
|
||
|
if (!data)
|
||
|
return -ENOMEM;
|
||
|
|
||
|
data->hdev = hdev;
|
||
|
timer_setup(&data->inrange_timer, letsketch_inrange_timeout, 0);
|
||
|
hid_set_drvdata(hdev, data);
|
||
|
|
||
|
ret = letsketch_setup_input_tablet(data);
|
||
|
if (ret)
|
||
|
return ret;
|
||
|
|
||
|
ret = letsketch_setup_input_tablet_pad(data);
|
||
|
if (ret)
|
||
|
return ret;
|
||
|
|
||
|
return hid_hw_start(hdev, HID_CONNECT_HIDRAW);
|
||
|
}
|
||
|
|
||
|
static const struct hid_device_id letsketch_devices[] = {
|
||
|
{ HID_USB_DEVICE(USB_VENDOR_ID_LETSKETCH, USB_DEVICE_ID_WP9620N) },
|
||
|
{ }
|
||
|
};
|
||
|
MODULE_DEVICE_TABLE(hid, letsketch_devices);
|
||
|
|
||
|
static struct hid_driver letsketch_driver = {
|
||
|
.name = "letsketch",
|
||
|
.id_table = letsketch_devices,
|
||
|
.probe = letsketch_probe,
|
||
|
.raw_event = letsketch_raw_event,
|
||
|
};
|
||
|
module_hid_driver(letsketch_driver);
|
||
|
|
||
|
MODULE_AUTHOR("Hans de Goede <hdegoede@redhat.com>");
|
||
|
MODULE_LICENSE("GPL");
|