xref: /linux/drivers/hid/usbhid/usbkbd.c (revision bba2c3615bd6cfee7456d1130f2e6b01b3f4e9ba)
1 // SPDX-License-Identifier: GPL-2.0-or-later
2 /*
3  *  Copyright (c) 1999-2001 Vojtech Pavlik
4  *
5  *  USB HIDBP Keyboard support
6  */
7 
8 /*
9  *
10  * Should you need to contact me, the author, you can do so either by
11  * e-mail - mail your message to <vojtech@ucw.cz>, or by paper mail:
12  * Vojtech Pavlik, Simunkova 1594, Prague 8, 182 00 Czech Republic
13  */
14 
15 #define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
16 
17 #include <linux/kernel.h>
18 #include <linux/slab.h>
19 #include <linux/module.h>
20 #include <linux/init.h>
21 #include <linux/usb/input.h>
22 #include <linux/hid.h>
23 #include <linux/seq_buf.h>
24 
25 /*
26  * Version Information
27  */
28 #define DRIVER_VERSION ""
29 #define DRIVER_AUTHOR "Vojtech Pavlik <vojtech@ucw.cz>"
30 #define DRIVER_DESC "USB HID Boot Protocol keyboard driver"
31 
32 MODULE_AUTHOR(DRIVER_AUTHOR);
33 MODULE_DESCRIPTION(DRIVER_DESC);
34 MODULE_LICENSE("GPL");
35 
36 static const unsigned char usb_kbd_keycode[256] = {
37 	  0,  0,  0,  0, 30, 48, 46, 32, 18, 33, 34, 35, 23, 36, 37, 38,
38 	 50, 49, 24, 25, 16, 19, 31, 20, 22, 47, 17, 45, 21, 44,  2,  3,
39 	  4,  5,  6,  7,  8,  9, 10, 11, 28,  1, 14, 15, 57, 12, 13, 26,
40 	 27, 43, 43, 39, 40, 41, 51, 52, 53, 58, 59, 60, 61, 62, 63, 64,
41 	 65, 66, 67, 68, 87, 88, 99, 70,119,110,102,104,111,107,109,106,
42 	105,108,103, 69, 98, 55, 74, 78, 96, 79, 80, 81, 75, 76, 77, 71,
43 	 72, 73, 82, 83, 86,127,116,117,183,184,185,186,187,188,189,190,
44 	191,192,193,194,134,138,130,132,128,129,131,137,133,135,136,113,
45 	115,114,  0,  0,  0,121,  0, 89, 93,124, 92, 94, 95,  0,  0,  0,
46 	122,123, 90, 91, 85,  0,  0,  0,  0,  0,  0,  0,  0,  0,  0,  0,
47 	  0,  0,  0,  0,  0,  0,  0,  0,  0,  0,  0,  0,  0,  0,  0,  0,
48 	  0,  0,  0,  0,  0,  0,  0,  0,  0,  0,  0,  0,  0,  0,  0,  0,
49 	  0,  0,  0,  0,  0,  0,  0,  0,  0,  0,  0,  0,  0,  0,  0,  0,
50 	  0,  0,  0,  0,  0,  0,  0,  0,  0,  0,  0,  0,  0,  0,  0,  0,
51 	 29, 42, 56,125, 97, 54,100,126,164,166,165,163,161,115,114,113,
52 	150,158,159,128,136,177,178,176,142,152,173,140
53 };
54 
55 
56 /**
57  * struct usb_kbd - state of each attached keyboard
58  * @dev:	input device associated with this keyboard
59  * @usbdev:	usb device associated with this keyboard
60  * @old:	data received in the past from the @irq URB representing which
61  *		keys were pressed. By comparing with the current list of keys
62  *		that are pressed, we are able to see key releases.
63  * @irq:	URB for receiving a list of keys that are pressed when a
64  *		new key is pressed or a key that was pressed is released.
65  * @led:	URB for sending LEDs (e.g. numlock, ...)
66  * @newleds:	data that will be sent with the @led URB representing which LEDs
67  *		should be on
68  * @name:	Name of the keyboard. @dev's name field points to this buffer
69  * @phys:	Physical path of the keyboard. @dev's phys field points to this
70  *		buffer
71  * @new:	Buffer for the @irq URB
72  * @cr:		Control request for @led URB
73  * @leds:	Buffer for the @led URB
74  * @new_dma:	DMA address for @irq URB
75  * @leds_dma:	DMA address for @led URB
76  * @leds_lock:	spinlock that protects @leds, @newleds, and @led_urb_submitted
77  * @led_urb_submitted: indicates whether @led is in progress, i.e. it has been
78  *		submitted and its completion handler has not returned yet
79  *		without	resubmitting @led
80  */
81 struct usb_kbd {
82 	struct input_dev *dev;
83 	struct usb_device *usbdev;
84 	unsigned char old[8];
85 	struct urb *irq, *led;
86 	unsigned char newleds;
87 	char name[128];
88 	char phys[64];
89 
90 	unsigned char *new;
91 	struct usb_ctrlrequest *cr;
92 	unsigned char *leds;
93 	dma_addr_t new_dma;
94 	dma_addr_t leds_dma;
95 
96 	spinlock_t leds_lock;
97 	bool led_urb_submitted;
98 
99 };
100 
101 static void usb_kbd_irq(struct urb *urb)
102 {
103 	struct usb_kbd *kbd = urb->context;
104 	int i;
105 
106 	switch (urb->status) {
107 	case 0:			/* success */
108 		break;
109 	case -ECONNRESET:	/* unlink */
110 	case -ENOENT:
111 	case -ESHUTDOWN:
112 		return;
113 	/* -EPIPE:  should clear the halt */
114 	default:		/* error */
115 		goto resubmit;
116 	}
117 
118 	for (i = 0; i < 8; i++)
119 		input_report_key(kbd->dev, usb_kbd_keycode[i + 224], (kbd->new[0] >> i) & 1);
120 
121 	for (i = 2; i < 8; i++) {
122 
123 		if (kbd->old[i] > 3 && memscan(kbd->new + 2, kbd->old[i], 6) == kbd->new + 8) {
124 			if (usb_kbd_keycode[kbd->old[i]])
125 				input_report_key(kbd->dev, usb_kbd_keycode[kbd->old[i]], 0);
126 			else
127 				hid_info(urb->dev,
128 					 "Unknown key (scancode %#x) released.\n",
129 					 kbd->old[i]);
130 		}
131 
132 		if (kbd->new[i] > 3 && memscan(kbd->old + 2, kbd->new[i], 6) == kbd->old + 8) {
133 			if (usb_kbd_keycode[kbd->new[i]])
134 				input_report_key(kbd->dev, usb_kbd_keycode[kbd->new[i]], 1);
135 			else
136 				hid_info(urb->dev,
137 					 "Unknown key (scancode %#x) pressed.\n",
138 					 kbd->new[i]);
139 		}
140 	}
141 
142 	input_sync(kbd->dev);
143 
144 	memcpy(kbd->old, kbd->new, 8);
145 
146 resubmit:
147 	i = usb_submit_urb (urb, GFP_ATOMIC);
148 	if (i)
149 		hid_err(urb->dev, "can't resubmit intr, %s-%s/input0, status %d",
150 			kbd->usbdev->bus->bus_name,
151 			kbd->usbdev->devpath, i);
152 }
153 
154 static int usb_kbd_event(struct input_dev *dev, unsigned int type,
155 			 unsigned int code, int value)
156 {
157 	unsigned long flags;
158 	struct usb_kbd *kbd = input_get_drvdata(dev);
159 
160 	if (type != EV_LED)
161 		return -1;
162 
163 	spin_lock_irqsave(&kbd->leds_lock, flags);
164 	kbd->newleds = (!!test_bit(LED_KANA,    dev->led) << 4) | (!!test_bit(LED_COMPOSE, dev->led) << 3) |
165 		       (!!test_bit(LED_SCROLLL, dev->led) << 2) | (!!test_bit(LED_CAPSL,   dev->led) << 1) |
166 		       (!!test_bit(LED_NUML,    dev->led));
167 
168 	if (kbd->led_urb_submitted){
169 		spin_unlock_irqrestore(&kbd->leds_lock, flags);
170 		return 0;
171 	}
172 
173 	if (*(kbd->leds) == kbd->newleds){
174 		spin_unlock_irqrestore(&kbd->leds_lock, flags);
175 		return 0;
176 	}
177 
178 	*(kbd->leds) = kbd->newleds;
179 
180 	kbd->led->dev = kbd->usbdev;
181 	if (usb_submit_urb(kbd->led, GFP_ATOMIC))
182 		pr_err("usb_submit_urb(leds) failed\n");
183 	else
184 		kbd->led_urb_submitted = true;
185 
186 	spin_unlock_irqrestore(&kbd->leds_lock, flags);
187 
188 	return 0;
189 }
190 
191 static void usb_kbd_led(struct urb *urb)
192 {
193 	unsigned long flags;
194 	struct usb_kbd *kbd = urb->context;
195 
196 	if (urb->status)
197 		hid_warn(urb->dev, "led urb status %d received\n",
198 			 urb->status);
199 
200 	spin_lock_irqsave(&kbd->leds_lock, flags);
201 
202 	if (*(kbd->leds) == kbd->newleds){
203 		kbd->led_urb_submitted = false;
204 		spin_unlock_irqrestore(&kbd->leds_lock, flags);
205 		return;
206 	}
207 
208 	*(kbd->leds) = kbd->newleds;
209 
210 	kbd->led->dev = kbd->usbdev;
211 	if (usb_submit_urb(kbd->led, GFP_ATOMIC)){
212 		hid_err(urb->dev, "usb_submit_urb(leds) failed\n");
213 		kbd->led_urb_submitted = false;
214 	}
215 	spin_unlock_irqrestore(&kbd->leds_lock, flags);
216 
217 }
218 
219 static int usb_kbd_open(struct input_dev *dev)
220 {
221 	struct usb_kbd *kbd = input_get_drvdata(dev);
222 
223 	kbd->irq->dev = kbd->usbdev;
224 	if (usb_submit_urb(kbd->irq, GFP_KERNEL))
225 		return -EIO;
226 
227 	return 0;
228 }
229 
230 static void usb_kbd_close(struct input_dev *dev)
231 {
232 	struct usb_kbd *kbd = input_get_drvdata(dev);
233 
234 	usb_kill_urb(kbd->irq);
235 }
236 
237 static int usb_kbd_alloc_mem(struct usb_device *dev, struct usb_kbd *kbd)
238 {
239 	if (!(kbd->irq = usb_alloc_urb(0, GFP_KERNEL)))
240 		return -1;
241 	if (!(kbd->led = usb_alloc_urb(0, GFP_KERNEL)))
242 		return -1;
243 	if (!(kbd->new = usb_alloc_coherent(dev, 8, GFP_KERNEL, &kbd->new_dma)))
244 		return -1;
245 	if (!(kbd->cr = kmalloc_obj(struct usb_ctrlrequest)))
246 		return -1;
247 	if (!(kbd->leds = usb_alloc_coherent(dev, 1, GFP_KERNEL, &kbd->leds_dma)))
248 		return -1;
249 
250 	return 0;
251 }
252 
253 static void usb_kbd_free_mem(struct usb_device *dev, struct usb_kbd *kbd)
254 {
255 	usb_free_urb(kbd->irq);
256 	usb_free_urb(kbd->led);
257 	usb_free_coherent(dev, 8, kbd->new, kbd->new_dma);
258 	kfree(kbd->cr);
259 	usb_free_coherent(dev, 1, kbd->leds, kbd->leds_dma);
260 }
261 
262 static int usb_kbd_probe(struct usb_interface *iface,
263 			 const struct usb_device_id *id)
264 {
265 	struct usb_device *dev = interface_to_usbdev(iface);
266 	struct usb_host_interface *interface;
267 	struct usb_endpoint_descriptor *endpoint;
268 	struct usb_kbd *kbd;
269 	struct input_dev *input_dev;
270 	struct seq_buf kbd_name;
271 	int i, pipe, maxp;
272 	int error = -ENOMEM;
273 	size_t len;
274 
275 	interface = iface->cur_altsetting;
276 
277 	if (interface->desc.bNumEndpoints != 1)
278 		return -ENODEV;
279 
280 	endpoint = &interface->endpoint[0].desc;
281 	if (!usb_endpoint_is_int_in(endpoint))
282 		return -ENODEV;
283 
284 	pipe = usb_rcvintpipe(dev, endpoint->bEndpointAddress);
285 	maxp = usb_maxpacket(dev, pipe);
286 
287 	kbd = kzalloc_obj(struct usb_kbd);
288 	input_dev = input_allocate_device();
289 	if (!kbd || !input_dev)
290 		goto fail1;
291 
292 	if (usb_kbd_alloc_mem(dev, kbd))
293 		goto fail2;
294 
295 	kbd->usbdev = dev;
296 	kbd->dev = input_dev;
297 	spin_lock_init(&kbd->leds_lock);
298 	seq_buf_init(&kbd_name, kbd->name, sizeof(kbd->name));
299 
300 	if (dev->manufacturer)
301 		seq_buf_puts(&kbd_name, dev->manufacturer);
302 
303 	if (dev->product) {
304 		if (dev->manufacturer)
305 			seq_buf_puts(&kbd_name, " ");
306 		seq_buf_puts(&kbd_name, dev->product);
307 	}
308 
309 	if (!seq_buf_used(&kbd_name))
310 		snprintf(kbd->name, sizeof(kbd->name),
311 			 "USB HIDBP Keyboard %04x:%04x",
312 			 le16_to_cpu(dev->descriptor.idVendor),
313 			 le16_to_cpu(dev->descriptor.idProduct));
314 
315 	usb_make_path(dev, kbd->phys, sizeof(kbd->phys));
316 	len = strnlen(kbd->phys, sizeof(kbd->phys));
317 	strscpy(kbd->phys + len, "/input0", sizeof(kbd->phys) - len);
318 
319 	input_dev->name = kbd->name;
320 	input_dev->phys = kbd->phys;
321 	usb_to_input_id(dev, &input_dev->id);
322 	input_dev->dev.parent = &iface->dev;
323 
324 	input_set_drvdata(input_dev, kbd);
325 
326 	input_dev->evbit[0] = BIT_MASK(EV_KEY) | BIT_MASK(EV_LED) |
327 		BIT_MASK(EV_REP);
328 	input_dev->ledbit[0] = BIT_MASK(LED_NUML) | BIT_MASK(LED_CAPSL) |
329 		BIT_MASK(LED_SCROLLL) | BIT_MASK(LED_COMPOSE) |
330 		BIT_MASK(LED_KANA);
331 
332 	for (i = 0; i < 255; i++)
333 		set_bit(usb_kbd_keycode[i], input_dev->keybit);
334 	clear_bit(0, input_dev->keybit);
335 
336 	input_dev->event = usb_kbd_event;
337 	input_dev->open = usb_kbd_open;
338 	input_dev->close = usb_kbd_close;
339 
340 	usb_fill_int_urb(kbd->irq, dev, pipe,
341 			 kbd->new, (maxp > 8 ? 8 : maxp),
342 			 usb_kbd_irq, kbd, endpoint->bInterval);
343 	kbd->irq->transfer_dma = kbd->new_dma;
344 	kbd->irq->transfer_flags |= URB_NO_TRANSFER_DMA_MAP;
345 
346 	kbd->cr->bRequestType = USB_TYPE_CLASS | USB_RECIP_INTERFACE;
347 	kbd->cr->bRequest = 0x09;
348 	kbd->cr->wValue = cpu_to_le16(0x200);
349 	kbd->cr->wIndex = cpu_to_le16(interface->desc.bInterfaceNumber);
350 	kbd->cr->wLength = cpu_to_le16(1);
351 
352 	usb_fill_control_urb(kbd->led, dev, usb_sndctrlpipe(dev, 0),
353 			     (void *) kbd->cr, kbd->leds, 1,
354 			     usb_kbd_led, kbd);
355 	kbd->led->transfer_dma = kbd->leds_dma;
356 	kbd->led->transfer_flags |= URB_NO_TRANSFER_DMA_MAP;
357 
358 	error = input_register_device(kbd->dev);
359 	if (error)
360 		goto fail2;
361 
362 	usb_set_intfdata(iface, kbd);
363 	device_set_wakeup_enable(&dev->dev, 1);
364 	return 0;
365 
366 fail2:
367 	usb_kbd_free_mem(dev, kbd);
368 fail1:
369 	input_free_device(input_dev);
370 	kfree(kbd);
371 	return error;
372 }
373 
374 static void usb_kbd_disconnect(struct usb_interface *intf)
375 {
376 	struct usb_kbd *kbd = usb_get_intfdata (intf);
377 
378 	usb_set_intfdata(intf, NULL);
379 	if (kbd) {
380 		usb_kill_urb(kbd->irq);
381 		input_unregister_device(kbd->dev);
382 		usb_kill_urb(kbd->led);
383 		usb_kbd_free_mem(interface_to_usbdev(intf), kbd);
384 		kfree(kbd);
385 	}
386 }
387 
388 static const struct usb_device_id usb_kbd_id_table[] = {
389 	{ USB_INTERFACE_INFO(USB_INTERFACE_CLASS_HID, USB_INTERFACE_SUBCLASS_BOOT,
390 		USB_INTERFACE_PROTOCOL_KEYBOARD) },
391 	{ }						/* Terminating entry */
392 };
393 
394 MODULE_DEVICE_TABLE (usb, usb_kbd_id_table);
395 
396 static struct usb_driver usb_kbd_driver = {
397 	.name =		"usbkbd",
398 	.probe =	usb_kbd_probe,
399 	.disconnect =	usb_kbd_disconnect,
400 	.id_table =	usb_kbd_id_table,
401 };
402 
403 module_usb_driver(usb_kbd_driver);
404