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authorDaniel Baumann <daniel.baumann@progress-linux.org>2024-04-07 18:49:45 +0000
committerDaniel Baumann <daniel.baumann@progress-linux.org>2024-04-07 18:49:45 +0000
commit2c3c1048746a4622d8c89a29670120dc8fab93c4 (patch)
tree848558de17fb3008cdf4d861b01ac7781903ce39 /drivers/hid/hid-letsketch.c
parentInitial commit. (diff)
downloadlinux-2c3c1048746a4622d8c89a29670120dc8fab93c4.tar.xz
linux-2c3c1048746a4622d8c89a29670120dc8fab93c4.zip
Adding upstream version 6.1.76.upstream/6.1.76
Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>
Diffstat (limited to 'drivers/hid/hid-letsketch.c')
-rw-r--r--drivers/hid/hid-letsketch.c322
1 files changed, 322 insertions, 0 deletions
diff --git a/drivers/hid/hid-letsketch.c b/drivers/hid/hid-letsketch.c
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index 000000000..74d17cf51
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+++ b/drivers/hid/hid-letsketch.c
@@ -0,0 +1,322 @@
+// 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");