xref: /linux/drivers/hid/usbhid/usbkbd.c (revision 9e56ff53b4115875667760445b028357848b4748)
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 
24 /*
25  * Version Information
26  */
27 #define DRIVER_VERSION ""
28 #define DRIVER_AUTHOR "Vojtech Pavlik <vojtech@ucw.cz>"
29 #define DRIVER_DESC "USB HID Boot Protocol keyboard driver"
30 
31 MODULE_AUTHOR(DRIVER_AUTHOR);
32 MODULE_DESCRIPTION(DRIVER_DESC);
33 MODULE_LICENSE("GPL");
34 
35 static const unsigned char usb_kbd_keycode[256] = {
36 	  0,  0,  0,  0, 30, 48, 46, 32, 18, 33, 34, 35, 23, 36, 37, 38,
37 	 50, 49, 24, 25, 16, 19, 31, 20, 22, 47, 17, 45, 21, 44,  2,  3,
38 	  4,  5,  6,  7,  8,  9, 10, 11, 28,  1, 14, 15, 57, 12, 13, 26,
39 	 27, 43, 43, 39, 40, 41, 51, 52, 53, 58, 59, 60, 61, 62, 63, 64,
40 	 65, 66, 67, 68, 87, 88, 99, 70,119,110,102,104,111,107,109,106,
41 	105,108,103, 69, 98, 55, 74, 78, 96, 79, 80, 81, 75, 76, 77, 71,
42 	 72, 73, 82, 83, 86,127,116,117,183,184,185,186,187,188,189,190,
43 	191,192,193,194,134,138,130,132,128,129,131,137,133,135,136,113,
44 	115,114,  0,  0,  0,121,  0, 89, 93,124, 92, 94, 95,  0,  0,  0,
45 	122,123, 90, 91, 85,  0,  0,  0,  0,  0,  0,  0,  0,  0,  0,  0,
46 	  0,  0,  0,  0,  0,  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 	 29, 42, 56,125, 97, 54,100,126,164,166,165,163,161,115,114,113,
51 	150,158,159,128,136,177,178,176,142,152,173,140
52 };
53 
54 
55 /**
56  * struct usb_kbd - state of each attached keyboard
57  * @dev:	input device associated with this keyboard
58  * @usbdev:	usb device associated with this keyboard
59  * @old:	data received in the past from the @irq URB representing which
60  *		keys were pressed. By comparing with the current list of keys
61  *		that are pressed, we are able to see key releases.
62  * @irq:	URB for receiving a list of keys that are pressed when a
63  *		new key is pressed or a key that was pressed is released.
64  * @led:	URB for sending LEDs (e.g. numlock, ...)
65  * @newleds:	data that will be sent with the @led URB representing which LEDs
66  *		should be on
67  * @name:	Name of the keyboard. @dev's name field points to this buffer
68  * @phys:	Physical path of the keyboard. @dev's phys field points to this
69  *		buffer
70  * @new:	Buffer for the @irq URB
71  * @cr:		Control request for @led URB
72  * @leds:	Buffer for the @led URB
73  * @new_dma:	DMA address for @irq URB
74  * @leds_dma:	DMA address for @led URB
75  * @leds_lock:	spinlock that protects @leds, @newleds, and @led_urb_submitted
76  * @led_urb_submitted: indicates whether @led is in progress, i.e. it has been
77  *		submitted and its completion handler has not returned yet
78  *		without	resubmitting @led
79  */
80 struct usb_kbd {
81 	struct input_dev *dev;
82 	struct usb_device *usbdev;
83 	unsigned char old[8];
84 	struct urb *irq, *led;
85 	unsigned char newleds;
86 	char name[128];
87 	char phys[64];
88 
89 	unsigned char *new;
90 	struct usb_ctrlrequest *cr;
91 	unsigned char *leds;
92 	dma_addr_t new_dma;
93 	dma_addr_t leds_dma;
94 
95 	spinlock_t leds_lock;
96 	bool led_urb_submitted;
97 
98 };
99 
100 static void usb_kbd_irq(struct urb *urb)
101 {
102 	struct usb_kbd *kbd = urb->context;
103 	int i;
104 
105 	switch (urb->status) {
106 	case 0:			/* success */
107 		break;
108 	case -ECONNRESET:	/* unlink */
109 	case -ENOENT:
110 	case -ESHUTDOWN:
111 		return;
112 	/* -EPIPE:  should clear the halt */
113 	default:		/* error */
114 		goto resubmit;
115 	}
116 
117 	for (i = 0; i < 8; i++)
118 		input_report_key(kbd->dev, usb_kbd_keycode[i + 224], (kbd->new[0] >> i) & 1);
119 
120 	for (i = 2; i < 8; i++) {
121 
122 		if (kbd->old[i] > 3 && memscan(kbd->new + 2, kbd->old[i], 6) == kbd->new + 8) {
123 			if (usb_kbd_keycode[kbd->old[i]])
124 				input_report_key(kbd->dev, usb_kbd_keycode[kbd->old[i]], 0);
125 			else
126 				hid_info(urb->dev,
127 					 "Unknown key (scancode %#x) released.\n",
128 					 kbd->old[i]);
129 		}
130 
131 		if (kbd->new[i] > 3 && memscan(kbd->old + 2, kbd->new[i], 6) == kbd->old + 8) {
132 			if (usb_kbd_keycode[kbd->new[i]])
133 				input_report_key(kbd->dev, usb_kbd_keycode[kbd->new[i]], 1);
134 			else
135 				hid_info(urb->dev,
136 					 "Unknown key (scancode %#x) pressed.\n",
137 					 kbd->new[i]);
138 		}
139 	}
140 
141 	input_sync(kbd->dev);
142 
143 	memcpy(kbd->old, kbd->new, 8);
144 
145 resubmit:
146 	i = usb_submit_urb (urb, GFP_ATOMIC);
147 	if (i)
148 		hid_err(urb->dev, "can't resubmit intr, %s-%s/input0, status %d",
149 			kbd->usbdev->bus->bus_name,
150 			kbd->usbdev->devpath, i);
151 }
152 
153 static int usb_kbd_event(struct input_dev *dev, unsigned int type,
154 			 unsigned int code, int value)
155 {
156 	unsigned long flags;
157 	struct usb_kbd *kbd = input_get_drvdata(dev);
158 
159 	if (type != EV_LED)
160 		return -1;
161 
162 	spin_lock_irqsave(&kbd->leds_lock, flags);
163 	kbd->newleds = (!!test_bit(LED_KANA,    dev->led) << 3) | (!!test_bit(LED_COMPOSE, dev->led) << 3) |
164 		       (!!test_bit(LED_SCROLLL, dev->led) << 2) | (!!test_bit(LED_CAPSL,   dev->led) << 1) |
165 		       (!!test_bit(LED_NUML,    dev->led));
166 
167 	if (kbd->led_urb_submitted){
168 		spin_unlock_irqrestore(&kbd->leds_lock, flags);
169 		return 0;
170 	}
171 
172 	if (*(kbd->leds) == kbd->newleds){
173 		spin_unlock_irqrestore(&kbd->leds_lock, flags);
174 		return 0;
175 	}
176 
177 	*(kbd->leds) = kbd->newleds;
178 
179 	kbd->led->dev = kbd->usbdev;
180 	if (usb_submit_urb(kbd->led, GFP_ATOMIC))
181 		pr_err("usb_submit_urb(leds) failed\n");
182 	else
183 		kbd->led_urb_submitted = true;
184 
185 	spin_unlock_irqrestore(&kbd->leds_lock, flags);
186 
187 	return 0;
188 }
189 
190 static void usb_kbd_led(struct urb *urb)
191 {
192 	unsigned long flags;
193 	struct usb_kbd *kbd = urb->context;
194 
195 	if (urb->status)
196 		hid_warn(urb->dev, "led urb status %d received\n",
197 			 urb->status);
198 
199 	spin_lock_irqsave(&kbd->leds_lock, flags);
200 
201 	if (*(kbd->leds) == kbd->newleds){
202 		kbd->led_urb_submitted = false;
203 		spin_unlock_irqrestore(&kbd->leds_lock, flags);
204 		return;
205 	}
206 
207 	*(kbd->leds) = kbd->newleds;
208 
209 	kbd->led->dev = kbd->usbdev;
210 	if (usb_submit_urb(kbd->led, GFP_ATOMIC)){
211 		hid_err(urb->dev, "usb_submit_urb(leds) failed\n");
212 		kbd->led_urb_submitted = false;
213 	}
214 	spin_unlock_irqrestore(&kbd->leds_lock, flags);
215 
216 }
217 
218 static int usb_kbd_open(struct input_dev *dev)
219 {
220 	struct usb_kbd *kbd = input_get_drvdata(dev);
221 
222 	kbd->irq->dev = kbd->usbdev;
223 	if (usb_submit_urb(kbd->irq, GFP_KERNEL))
224 		return -EIO;
225 
226 	return 0;
227 }
228 
229 static void usb_kbd_close(struct input_dev *dev)
230 {
231 	struct usb_kbd *kbd = input_get_drvdata(dev);
232 
233 	usb_kill_urb(kbd->irq);
234 }
235 
236 static int usb_kbd_alloc_mem(struct usb_device *dev, struct usb_kbd *kbd)
237 {
238 	if (!(kbd->irq = usb_alloc_urb(0, GFP_KERNEL)))
239 		return -1;
240 	if (!(kbd->led = usb_alloc_urb(0, GFP_KERNEL)))
241 		return -1;
242 	if (!(kbd->new = usb_alloc_coherent(dev, 8, GFP_KERNEL, &kbd->new_dma)))
243 		return -1;
244 	if (!(kbd->cr = kmalloc(sizeof(struct usb_ctrlrequest), GFP_KERNEL)))
245 		return -1;
246 	if (!(kbd->leds = usb_alloc_coherent(dev, 1, GFP_KERNEL, &kbd->leds_dma)))
247 		return -1;
248 
249 	return 0;
250 }
251 
252 static void usb_kbd_free_mem(struct usb_device *dev, struct usb_kbd *kbd)
253 {
254 	usb_free_urb(kbd->irq);
255 	usb_free_urb(kbd->led);
256 	usb_free_coherent(dev, 8, kbd->new, kbd->new_dma);
257 	kfree(kbd->cr);
258 	usb_free_coherent(dev, 1, kbd->leds, kbd->leds_dma);
259 }
260 
261 static int usb_kbd_probe(struct usb_interface *iface,
262 			 const struct usb_device_id *id)
263 {
264 	struct usb_device *dev = interface_to_usbdev(iface);
265 	struct usb_host_interface *interface;
266 	struct usb_endpoint_descriptor *endpoint;
267 	struct usb_kbd *kbd;
268 	struct input_dev *input_dev;
269 	int i, pipe, maxp;
270 	int error = -ENOMEM;
271 
272 	interface = iface->cur_altsetting;
273 
274 	if (interface->desc.bNumEndpoints != 1)
275 		return -ENODEV;
276 
277 	endpoint = &interface->endpoint[0].desc;
278 	if (!usb_endpoint_is_int_in(endpoint))
279 		return -ENODEV;
280 
281 	pipe = usb_rcvintpipe(dev, endpoint->bEndpointAddress);
282 	maxp = usb_maxpacket(dev, pipe);
283 
284 	kbd = kzalloc(sizeof(struct usb_kbd), GFP_KERNEL);
285 	input_dev = input_allocate_device();
286 	if (!kbd || !input_dev)
287 		goto fail1;
288 
289 	if (usb_kbd_alloc_mem(dev, kbd))
290 		goto fail2;
291 
292 	kbd->usbdev = dev;
293 	kbd->dev = input_dev;
294 	spin_lock_init(&kbd->leds_lock);
295 
296 	if (dev->manufacturer)
297 		strscpy(kbd->name, dev->manufacturer, sizeof(kbd->name));
298 
299 	if (dev->product) {
300 		if (dev->manufacturer)
301 			strlcat(kbd->name, " ", sizeof(kbd->name));
302 		strlcat(kbd->name, dev->product, sizeof(kbd->name));
303 	}
304 
305 	if (!strlen(kbd->name))
306 		snprintf(kbd->name, sizeof(kbd->name),
307 			 "USB HIDBP Keyboard %04x:%04x",
308 			 le16_to_cpu(dev->descriptor.idVendor),
309 			 le16_to_cpu(dev->descriptor.idProduct));
310 
311 	usb_make_path(dev, kbd->phys, sizeof(kbd->phys));
312 	strlcat(kbd->phys, "/input0", sizeof(kbd->phys));
313 
314 	input_dev->name = kbd->name;
315 	input_dev->phys = kbd->phys;
316 	usb_to_input_id(dev, &input_dev->id);
317 	input_dev->dev.parent = &iface->dev;
318 
319 	input_set_drvdata(input_dev, kbd);
320 
321 	input_dev->evbit[0] = BIT_MASK(EV_KEY) | BIT_MASK(EV_LED) |
322 		BIT_MASK(EV_REP);
323 	input_dev->ledbit[0] = BIT_MASK(LED_NUML) | BIT_MASK(LED_CAPSL) |
324 		BIT_MASK(LED_SCROLLL) | BIT_MASK(LED_COMPOSE) |
325 		BIT_MASK(LED_KANA);
326 
327 	for (i = 0; i < 255; i++)
328 		set_bit(usb_kbd_keycode[i], input_dev->keybit);
329 	clear_bit(0, input_dev->keybit);
330 
331 	input_dev->event = usb_kbd_event;
332 	input_dev->open = usb_kbd_open;
333 	input_dev->close = usb_kbd_close;
334 
335 	usb_fill_int_urb(kbd->irq, dev, pipe,
336 			 kbd->new, (maxp > 8 ? 8 : maxp),
337 			 usb_kbd_irq, kbd, endpoint->bInterval);
338 	kbd->irq->transfer_dma = kbd->new_dma;
339 	kbd->irq->transfer_flags |= URB_NO_TRANSFER_DMA_MAP;
340 
341 	kbd->cr->bRequestType = USB_TYPE_CLASS | USB_RECIP_INTERFACE;
342 	kbd->cr->bRequest = 0x09;
343 	kbd->cr->wValue = cpu_to_le16(0x200);
344 	kbd->cr->wIndex = cpu_to_le16(interface->desc.bInterfaceNumber);
345 	kbd->cr->wLength = cpu_to_le16(1);
346 
347 	usb_fill_control_urb(kbd->led, dev, usb_sndctrlpipe(dev, 0),
348 			     (void *) kbd->cr, kbd->leds, 1,
349 			     usb_kbd_led, kbd);
350 	kbd->led->transfer_dma = kbd->leds_dma;
351 	kbd->led->transfer_flags |= URB_NO_TRANSFER_DMA_MAP;
352 
353 	error = input_register_device(kbd->dev);
354 	if (error)
355 		goto fail2;
356 
357 	usb_set_intfdata(iface, kbd);
358 	device_set_wakeup_enable(&dev->dev, 1);
359 	return 0;
360 
361 fail2:
362 	usb_kbd_free_mem(dev, kbd);
363 fail1:
364 	input_free_device(input_dev);
365 	kfree(kbd);
366 	return error;
367 }
368 
369 static void usb_kbd_disconnect(struct usb_interface *intf)
370 {
371 	struct usb_kbd *kbd = usb_get_intfdata (intf);
372 
373 	usb_set_intfdata(intf, NULL);
374 	if (kbd) {
375 		usb_kill_urb(kbd->irq);
376 		input_unregister_device(kbd->dev);
377 		usb_kill_urb(kbd->led);
378 		usb_kbd_free_mem(interface_to_usbdev(intf), kbd);
379 		kfree(kbd);
380 	}
381 }
382 
383 static const struct usb_device_id usb_kbd_id_table[] = {
384 	{ USB_INTERFACE_INFO(USB_INTERFACE_CLASS_HID, USB_INTERFACE_SUBCLASS_BOOT,
385 		USB_INTERFACE_PROTOCOL_KEYBOARD) },
386 	{ }						/* Terminating entry */
387 };
388 
389 MODULE_DEVICE_TABLE (usb, usb_kbd_id_table);
390 
391 static struct usb_driver usb_kbd_driver = {
392 	.name =		"usbkbd",
393 	.probe =	usb_kbd_probe,
394 	.disconnect =	usb_kbd_disconnect,
395 	.id_table =	usb_kbd_id_table,
396 };
397 
398 module_usb_driver(usb_kbd_driver);
399