/drivers/input/tablet/kbtab.c

  1// SPDX-License-Identifier: GPL-2.0-only
  2#include <linux/kernel.h>
  3#include <linux/slab.h>
  4#include <linux/module.h>
  5#include <linux/usb/input.h>
  6#include <asm/unaligned.h>
  7
  8/*
  9 * Pressure-threshold modules param code from Alex Perry <alex.perry@ieee.org>
 10 */
 11
 12MODULE_AUTHOR("Josh Myer <josh@joshisanerd.com>");
 13MODULE_DESCRIPTION("USB KB Gear JamStudio Tablet driver");
 14MODULE_LICENSE("GPL");
 15
 16#define USB_VENDOR_ID_KBGEAR	0x084e
 17
 18static int kb_pressure_click = 0x10;
 19module_param(kb_pressure_click, int, 0);
 20MODULE_PARM_DESC(kb_pressure_click, "pressure threshold for clicks");
 21
 22struct kbtab {
 23	unsigned char *data;
 24	dma_addr_t data_dma;
 25	struct input_dev *dev;
 26	struct usb_interface *intf;
 27	struct urb *irq;
 28	char phys[32];
 29};
 30
 31static void kbtab_irq(struct urb *urb)
 32{
 33	struct kbtab *kbtab = urb->context;
 34	unsigned char *data = kbtab->data;
 35	struct input_dev *dev = kbtab->dev;
 36	int pressure;
 37	int retval;
 38
 39	switch (urb->status) {
 40	case 0:
 41		/* success */
 42		break;
 43	case -ECONNRESET:
 44	case -ENOENT:
 45	case -ESHUTDOWN:
 46		/* this urb is terminated, clean up */
 47		dev_dbg(&kbtab->intf->dev,
 48			"%s - urb shutting down with status: %d\n",
 49			__func__, urb->status);
 50		return;
 51	default:
 52		dev_dbg(&kbtab->intf->dev,
 53			"%s - nonzero urb status received: %d\n",
 54			__func__, urb->status);
 55		goto exit;
 56	}
 57
 58
 59	input_report_key(dev, BTN_TOOL_PEN, 1);
 60
 61	input_report_abs(dev, ABS_X, get_unaligned_le16(&data[1]));
 62	input_report_abs(dev, ABS_Y, get_unaligned_le16(&data[3]));
 63
 64	/*input_report_key(dev, BTN_TOUCH , data[0] & 0x01);*/
 65	input_report_key(dev, BTN_RIGHT, data[0] & 0x02);
 66
 67	pressure = data[5];
 68	if (kb_pressure_click == -1)
 69		input_report_abs(dev, ABS_PRESSURE, pressure);
 70	else
 71		input_report_key(dev, BTN_LEFT, pressure > kb_pressure_click ? 1 : 0);
 72
 73	input_sync(dev);
 74
 75 exit:
 76	retval = usb_submit_urb(urb, GFP_ATOMIC);
 77	if (retval)
 78		dev_err(&kbtab->intf->dev,
 79			"%s - usb_submit_urb failed with result %d\n",
 80			__func__, retval);
 81}
 82
 83static const struct usb_device_id kbtab_ids[] = {
 84	{ USB_DEVICE(USB_VENDOR_ID_KBGEAR, 0x1001), .driver_info = 0 },
 85	{ }
 86};
 87
 88MODULE_DEVICE_TABLE(usb, kbtab_ids);
 89
 90static int kbtab_open(struct input_dev *dev)
 91{
 92	struct kbtab *kbtab = input_get_drvdata(dev);
 93	struct usb_device *udev = interface_to_usbdev(kbtab->intf);
 94
 95	kbtab->irq->dev = udev;
 96	if (usb_submit_urb(kbtab->irq, GFP_KERNEL))
 97		return -EIO;
 98
 99	return 0;
100}
101
102static void kbtab_close(struct input_dev *dev)
103{
104	struct kbtab *kbtab = input_get_drvdata(dev);
105
106	usb_kill_urb(kbtab->irq);
107}
108
109static int kbtab_probe(struct usb_interface *intf, const struct usb_device_id *id)
110{
111	struct usb_device *dev = interface_to_usbdev(intf);
112	struct usb_endpoint_descriptor *endpoint;
113	struct kbtab *kbtab;
114	struct input_dev *input_dev;
115	int error = -ENOMEM;
116
117	if (intf->cur_altsetting->desc.bNumEndpoints < 1)
118		return -ENODEV;
119
120	endpoint = &intf->cur_altsetting->endpoint[0].desc;
121	if (!usb_endpoint_is_int_in(endpoint))
122		return -ENODEV;
123
124	kbtab = kzalloc(sizeof(struct kbtab), GFP_KERNEL);
125	input_dev = input_allocate_device();
126	if (!kbtab || !input_dev)
127		goto fail1;
128
129	kbtab->data = usb_alloc_coherent(dev, 8, GFP_KERNEL, &kbtab->data_dma);
130	if (!kbtab->data)
131		goto fail1;
132
133	kbtab->irq = usb_alloc_urb(0, GFP_KERNEL);
134	if (!kbtab->irq)
135		goto fail2;
136
137	kbtab->intf = intf;
138	kbtab->dev = input_dev;
139
140	usb_make_path(dev, kbtab->phys, sizeof(kbtab->phys));
141	strlcat(kbtab->phys, "/input0", sizeof(kbtab->phys));
142
143	input_dev->name = "KB Gear Tablet";
144	input_dev->phys = kbtab->phys;
145	usb_to_input_id(dev, &input_dev->id);
146	input_dev->dev.parent = &intf->dev;
147
148	input_set_drvdata(input_dev, kbtab);
149
150	input_dev->open = kbtab_open;
151	input_dev->close = kbtab_close;
152
153	input_dev->evbit[0] |= BIT_MASK(EV_KEY) | BIT_MASK(EV_ABS);
154	input_dev->keybit[BIT_WORD(BTN_LEFT)] |=
155		BIT_MASK(BTN_LEFT) | BIT_MASK(BTN_RIGHT);
156	input_dev->keybit[BIT_WORD(BTN_DIGI)] |=
157		BIT_MASK(BTN_TOOL_PEN) | BIT_MASK(BTN_TOUCH);
158	input_set_abs_params(input_dev, ABS_X, 0, 0x2000, 4, 0);
159	input_set_abs_params(input_dev, ABS_Y, 0, 0x1750, 4, 0);
160	input_set_abs_params(input_dev, ABS_PRESSURE, 0, 0xff, 0, 0);
161
162	usb_fill_int_urb(kbtab->irq, dev,
163			 usb_rcvintpipe(dev, endpoint->bEndpointAddress),
164			 kbtab->data, 8,
165			 kbtab_irq, kbtab, endpoint->bInterval);
166	kbtab->irq->transfer_dma = kbtab->data_dma;
167	kbtab->irq->transfer_flags |= URB_NO_TRANSFER_DMA_MAP;
168
169	error = input_register_device(kbtab->dev);
170	if (error)
171		goto fail3;
172
173	usb_set_intfdata(intf, kbtab);
174
175	return 0;
176
177 fail3:	usb_free_urb(kbtab->irq);
178 fail2:	usb_free_coherent(dev, 8, kbtab->data, kbtab->data_dma);
179 fail1:	input_free_device(input_dev);
180	kfree(kbtab);
181	return error;
182}
183
184static void kbtab_disconnect(struct usb_interface *intf)
185{
186	struct kbtab *kbtab = usb_get_intfdata(intf);
187	struct usb_device *udev = interface_to_usbdev(intf);
188
189	usb_set_intfdata(intf, NULL);
190
191	input_unregister_device(kbtab->dev);
192	usb_free_urb(kbtab->irq);
193	usb_free_coherent(udev, 8, kbtab->data, kbtab->data_dma);
194	kfree(kbtab);
195}
196
197static struct usb_driver kbtab_driver = {
198	.name =		"kbtab",
199	.probe =	kbtab_probe,
200	.disconnect =	kbtab_disconnect,
201	.id_table =	kbtab_ids,
202};
203
204module_usb_driver(kbtab_driver);