input/tablet/kbtab.c

0001 // SPDX-License-Identifier: GPL-2.0-only
0002 #include <linux/kernel.h>
0003 #include <linux/slab.h>
0004 #include <linux/module.h>
0005 #include <linux/usb/input.h>
0006 #include <asm/unaligned.h>
0007
0008 /*
0009  * Pressure-threshold modules param code from Alex Perry <alex.perry@ieee.org>
0010  */
0011
0012 MODULE_AUTHOR("Josh Myer <josh@joshisanerd.com>");
0013 MODULE_DESCRIPTION("USB KB Gear JamStudio Tablet driver");
0014 MODULE_LICENSE("GPL");
0015
0016 #define USB_VENDOR_ID_KBGEAR    0x084e
0017
0018 static int kb_pressure_click = 0x10;
0019 module_param(kb_pressure_click, int, 0);
0020 MODULE_PARM_DESC(kb_pressure_click, "pressure threshold for clicks");
0021
0022 struct kbtab {
0023     unsigned char *data;
0024     dma_addr_t data_dma;
0025     struct input_dev *dev;
0026     struct usb_interface *intf;
0027     struct urb *irq;
0028     char phys[32];
0029 };
0030
0031 static void kbtab_irq(struct urb *urb)
0032 {
0033     struct kbtab *kbtab = urb->context;
0034     unsigned char *data = kbtab->data;
0035     struct input_dev *dev = kbtab->dev;
0036     int pressure;
0037     int retval;
0038
0039     switch (urb->status) {
0040     case 0:
0041         /* success */
0042         break;
0043     case -ECONNRESET:
0044     case -ENOENT:
0045     case -ESHUTDOWN:
0046         /* this urb is terminated, clean up */
0047         dev_dbg(&kbtab->intf->dev,
0048             "%s - urb shutting down with status: %d\n",
0049             __func__, urb->status);
0050         return;
0051     default:
0052         dev_dbg(&kbtab->intf->dev,
0053             "%s - nonzero urb status received: %d\n",
0054             __func__, urb->status);
0055         goto exit;
0056     }
0057
0058
0059     input_report_key(dev, BTN_TOOL_PEN, 1);
0060
0061     input_report_abs(dev, ABS_X, get_unaligned_le16(&data[1]));
0062     input_report_abs(dev, ABS_Y, get_unaligned_le16(&data[3]));
0063
0064     /*input_report_key(dev, BTN_TOUCH , data[0] & 0x01);*/
0065     input_report_key(dev, BTN_RIGHT, data[0] & 0x02);
0066
0067     pressure = data[5];
0068     if (kb_pressure_click == -1)
0069         input_report_abs(dev, ABS_PRESSURE, pressure);
0070     else
0071         input_report_key(dev, BTN_LEFT, pressure > kb_pressure_click ? 1 : 0);
0072
0073     input_sync(dev);
0074
0075  exit:
0076     retval = usb_submit_urb(urb, GFP_ATOMIC);
0077     if (retval)
0078         dev_err(&kbtab->intf->dev,
0079             "%s - usb_submit_urb failed with result %d\n",
0080             __func__, retval);
0081 }
0082
0083 static const struct usb_device_id kbtab_ids[] = {
0084     { USB_DEVICE(USB_VENDOR_ID_KBGEAR, 0x1001), .driver_info = 0 },
0085     { }
0086 };
0087
0088 MODULE_DEVICE_TABLE(usb, kbtab_ids);
0089
0090 static int kbtab_open(struct input_dev *dev)
0091 {
0092     struct kbtab *kbtab = input_get_drvdata(dev);
0093     struct usb_device *udev = interface_to_usbdev(kbtab->intf);
0094
0095     kbtab->irq->dev = udev;
0096     if (usb_submit_urb(kbtab->irq, GFP_KERNEL))
0097         return -EIO;
0098
0099     return 0;
0100 }
0101
0102 static void kbtab_close(struct input_dev *dev)
0103 {
0104     struct kbtab *kbtab = input_get_drvdata(dev);
0105
0106     usb_kill_urb(kbtab->irq);
0107 }
0108
0109 static int kbtab_probe(struct usb_interface *intf, const struct usb_device_id *id)
0110 {
0111     struct usb_device *dev = interface_to_usbdev(intf);
0112     struct usb_endpoint_descriptor *endpoint;
0113     struct kbtab *kbtab;
0114     struct input_dev *input_dev;
0115     int error = -ENOMEM;
0116
0117     if (intf->cur_altsetting->desc.bNumEndpoints < 1)
0118         return -ENODEV;
0119
0120     endpoint = &intf->cur_altsetting->endpoint[0].desc;
0121     if (!usb_endpoint_is_int_in(endpoint))
0122         return -ENODEV;
0123
0124     kbtab = kzalloc(sizeof(struct kbtab), GFP_KERNEL);
0125     input_dev = input_allocate_device();
0126     if (!kbtab || !input_dev)
0127         goto fail1;
0128
0129     kbtab->data = usb_alloc_coherent(dev, 8, GFP_KERNEL, &kbtab->data_dma);
0130     if (!kbtab->data)
0131         goto fail1;
0132
0133     kbtab->irq = usb_alloc_urb(0, GFP_KERNEL);
0134     if (!kbtab->irq)
0135         goto fail2;
0136
0137     kbtab->intf = intf;
0138     kbtab->dev = input_dev;
0139
0140     usb_make_path(dev, kbtab->phys, sizeof(kbtab->phys));
0141     strlcat(kbtab->phys, "/input0", sizeof(kbtab->phys));
0142
0143     input_dev->name = "KB Gear Tablet";
0144     input_dev->phys = kbtab->phys;
0145     usb_to_input_id(dev, &input_dev->id);
0146     input_dev->dev.parent = &intf->dev;
0147
0148     input_set_drvdata(input_dev, kbtab);
0149
0150     input_dev->open = kbtab_open;
0151     input_dev->close = kbtab_close;
0152
0153     input_dev->evbit[0] |= BIT_MASK(EV_KEY) | BIT_MASK(EV_ABS);
0154     input_dev->keybit[BIT_WORD(BTN_LEFT)] |=
0155         BIT_MASK(BTN_LEFT) | BIT_MASK(BTN_RIGHT);
0156     input_dev->keybit[BIT_WORD(BTN_DIGI)] |=
0157         BIT_MASK(BTN_TOOL_PEN) | BIT_MASK(BTN_TOUCH);
0158     input_set_abs_params(input_dev, ABS_X, 0, 0x2000, 4, 0);
0159     input_set_abs_params(input_dev, ABS_Y, 0, 0x1750, 4, 0);
0160     input_set_abs_params(input_dev, ABS_PRESSURE, 0, 0xff, 0, 0);
0161
0162     usb_fill_int_urb(kbtab->irq, dev,
0163              usb_rcvintpipe(dev, endpoint->bEndpointAddress),
0164              kbtab->data, 8,
0165              kbtab_irq, kbtab, endpoint->bInterval);
0166     kbtab->irq->transfer_dma = kbtab->data_dma;
0167     kbtab->irq->transfer_flags |= URB_NO_TRANSFER_DMA_MAP;
0168
0169     error = input_register_device(kbtab->dev);
0170     if (error)
0171         goto fail3;
0172
0173     usb_set_intfdata(intf, kbtab);
0174
0175     return 0;
0176
0177  fail3: usb_free_urb(kbtab->irq);
0178  fail2: usb_free_coherent(dev, 8, kbtab->data, kbtab->data_dma);
0179  fail1: input_free_device(input_dev);
0180     kfree(kbtab);
0181     return error;
0182 }
0183
0184 static void kbtab_disconnect(struct usb_interface *intf)
0185 {
0186     struct kbtab *kbtab = usb_get_intfdata(intf);
0187     struct usb_device *udev = interface_to_usbdev(intf);
0188
0189     usb_set_intfdata(intf, NULL);
0190
0191     input_unregister_device(kbtab->dev);
0192     usb_free_urb(kbtab->irq);
0193     usb_free_coherent(udev, 8, kbtab->data, kbtab->data_dma);
0194     kfree(kbtab);
0195 }
0196
0197 static struct usb_driver kbtab_driver = {
0198     .name =     "kbtab",
0199     .probe =    kbtab_probe,
0200     .disconnect =   kbtab_disconnect,
0201     .id_table = kbtab_ids,
0202 };
0203
0204 module_usb_driver(kbtab_driver);