Bootlin logo

Elixir Cross Referencer

  1
  2
  3
  4
  5
  6
  7
  8
  9
 10
 11
 12
 13
 14
 15
 16
 17
 18
 19
 20
 21
 22
 23
 24
 25
 26
 27
 28
 29
 30
 31
 32
 33
 34
 35
 36
 37
 38
 39
 40
 41
 42
 43
 44
 45
 46
 47
 48
 49
 50
 51
 52
 53
 54
 55
 56
 57
 58
 59
 60
 61
 62
 63
 64
 65
 66
 67
 68
 69
 70
 71
 72
 73
 74
 75
 76
 77
 78
 79
 80
 81
 82
 83
 84
 85
 86
 87
 88
 89
 90
 91
 92
 93
 94
 95
 96
 97
 98
 99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
299
300
301
302
303
304
305
306
307
308
309
310
311
312
313
314
315
316
317
318
319
320
321
322
323
324
325
326
327
328
329
330
331
332
333
334
335
336
337
338
339
340
341
342
343
344
345
346
347
348
349
350
351
352
353
354
355
356
357
358
359
360
361
362
363
364
365
366
367
368
369
370
371
372
373
374
375
376
377
378
379
380
381
382
383
384
385
386
387
388
389
390
391
392
393
394
395
396
397
398
399
400
401
402
403
404
405
406
407
408
409
410
411
412
413
414
415
416
417
418
419
420
421
422
423
424
425
426
427
428
429
430
431
432
433
434
435
436
437
438
439
/*
 * dbgp.c -- EHCI Debug Port device gadget
 *
 * Copyright (C) 2010 Stephane Duverger
 *
 * Released under the GPLv2.
 */

/* verbose messages */
#include <linux/kernel.h>
#include <linux/device.h>
#include <linux/module.h>
#include <linux/usb/ch9.h>
#include <linux/usb/gadget.h>

#include "u_serial.h"

#define DRIVER_VENDOR_ID	0x0525 /* NetChip */
#define DRIVER_PRODUCT_ID	0xc0de /* undefined */

#define USB_DEBUG_MAX_PACKET_SIZE     8
#define DBGP_REQ_EP0_LEN              128
#define DBGP_REQ_LEN                  512

static struct dbgp {
	struct usb_gadget  *gadget;
	struct usb_request *req;
	struct usb_ep      *i_ep;
	struct usb_ep      *o_ep;
#ifdef CONFIG_USB_G_DBGP_SERIAL
	struct gserial     *serial;
#endif
} dbgp;

static struct usb_device_descriptor device_desc = {
	.bLength = sizeof device_desc,
	.bDescriptorType = USB_DT_DEVICE,
	.bcdUSB = __constant_cpu_to_le16(0x0200),
	.bDeviceClass =	USB_CLASS_VENDOR_SPEC,
	.idVendor = __constant_cpu_to_le16(DRIVER_VENDOR_ID),
	.idProduct = __constant_cpu_to_le16(DRIVER_PRODUCT_ID),
	.bNumConfigurations = 1,
};

static struct usb_debug_descriptor dbg_desc = {
	.bLength = sizeof dbg_desc,
	.bDescriptorType = USB_DT_DEBUG,
};

static struct usb_endpoint_descriptor i_desc = {
	.bLength = USB_DT_ENDPOINT_SIZE,
	.bDescriptorType = USB_DT_ENDPOINT,
	.bmAttributes = USB_ENDPOINT_XFER_BULK,
	.bEndpointAddress = USB_DIR_IN,
};

static struct usb_endpoint_descriptor o_desc = {
	.bLength = USB_DT_ENDPOINT_SIZE,
	.bDescriptorType = USB_DT_ENDPOINT,
	.bmAttributes = USB_ENDPOINT_XFER_BULK,
	.bEndpointAddress = USB_DIR_OUT,
};

#ifdef CONFIG_USB_G_DBGP_PRINTK
static int dbgp_consume(char *buf, unsigned len)
{
	char c;

	if (!len)
		return 0;

	c = buf[len-1];
	if (c != 0)
		buf[len-1] = 0;

	printk(KERN_NOTICE "%s%c", buf, c);
	return 0;
}

static void __disable_ep(struct usb_ep *ep)
{
	if (ep && ep->driver_data == dbgp.gadget) {
		usb_ep_disable(ep);
		ep->driver_data = NULL;
	}
}

static void dbgp_disable_ep(void)
{
	__disable_ep(dbgp.i_ep);
	__disable_ep(dbgp.o_ep);
}

static void dbgp_complete(struct usb_ep *ep, struct usb_request *req)
{
	int stp;
	int err = 0;
	int status = req->status;

	if (ep == dbgp.i_ep) {
		stp = 1;
		goto fail;
	}

	if (status != 0) {
		stp = 2;
		goto release_req;
	}

	dbgp_consume(req->buf, req->actual);

	req->length = DBGP_REQ_LEN;
	err = usb_ep_queue(ep, req, GFP_ATOMIC);
	if (err < 0) {
		stp = 3;
		goto release_req;
	}

	return;

release_req:
	kfree(req->buf);
	usb_ep_free_request(dbgp.o_ep, req);
	dbgp_disable_ep();
fail:
	dev_dbg(&dbgp.gadget->dev,
		"complete: failure (%d:%d) ==> %d\n", stp, err, status);
}

static int dbgp_enable_ep_req(struct usb_ep *ep)
{
	int err, stp;
	struct usb_request *req;

	req = usb_ep_alloc_request(ep, GFP_KERNEL);
	if (!req) {
		err = -ENOMEM;
		stp = 1;
		goto fail_1;
	}

	req->buf = kmalloc(DBGP_REQ_LEN, GFP_KERNEL);
	if (!req->buf) {
		err = -ENOMEM;
		stp = 2;
		goto fail_2;
	}

	req->complete = dbgp_complete;
	req->length = DBGP_REQ_LEN;
	err = usb_ep_queue(ep, req, GFP_ATOMIC);
	if (err < 0) {
		stp = 3;
		goto fail_3;
	}

	return 0;

fail_3:
	kfree(req->buf);
fail_2:
	usb_ep_free_request(dbgp.o_ep, req);
fail_1:
	dev_dbg(&dbgp.gadget->dev,
		"enable ep req: failure (%d:%d)\n", stp, err);
	return err;
}

static int __enable_ep(struct usb_ep *ep, struct usb_endpoint_descriptor *desc)
{
	int err;
	ep->desc = desc;
	err = usb_ep_enable(ep);
	ep->driver_data = dbgp.gadget;
	return err;
}

static int dbgp_enable_ep(void)
{
	int err, stp;

	err = __enable_ep(dbgp.i_ep, &i_desc);
	if (err < 0) {
		stp = 1;
		goto fail_1;
	}

	err = __enable_ep(dbgp.o_ep, &o_desc);
	if (err < 0) {
		stp = 2;
		goto fail_2;
	}

	err = dbgp_enable_ep_req(dbgp.o_ep);
	if (err < 0) {
		stp = 3;
		goto fail_3;
	}

	return 0;

fail_3:
	__disable_ep(dbgp.o_ep);
fail_2:
	__disable_ep(dbgp.i_ep);
fail_1:
	dev_dbg(&dbgp.gadget->dev, "enable ep: failure (%d:%d)\n", stp, err);
	return err;
}
#endif

static void dbgp_disconnect(struct usb_gadget *gadget)
{
#ifdef CONFIG_USB_G_DBGP_PRINTK
	dbgp_disable_ep();
#else
	gserial_disconnect(dbgp.serial);
#endif
}

static void dbgp_unbind(struct usb_gadget *gadget)
{
#ifdef CONFIG_USB_G_DBGP_SERIAL
	kfree(dbgp.serial);
	dbgp.serial = NULL;
#endif
	if (dbgp.req) {
		kfree(dbgp.req->buf);
		usb_ep_free_request(gadget->ep0, dbgp.req);
		dbgp.req = NULL;
	}

	gadget->ep0->driver_data = NULL;
}

#ifdef CONFIG_USB_G_DBGP_SERIAL
static unsigned char tty_line;
#endif

static int dbgp_configure_endpoints(struct usb_gadget *gadget)
{
	int stp;

	usb_ep_autoconfig_reset(gadget);

	dbgp.i_ep = usb_ep_autoconfig(gadget, &i_desc);
	if (!dbgp.i_ep) {
		stp = 1;
		goto fail_1;
	}

	dbgp.i_ep->driver_data = gadget;
	i_desc.wMaxPacketSize =
		__constant_cpu_to_le16(USB_DEBUG_MAX_PACKET_SIZE);

	dbgp.o_ep = usb_ep_autoconfig(gadget, &o_desc);
	if (!dbgp.o_ep) {
		dbgp.i_ep->driver_data = NULL;
		stp = 2;
		goto fail_2;
	}

	dbgp.o_ep->driver_data = gadget;
	o_desc.wMaxPacketSize =
		__constant_cpu_to_le16(USB_DEBUG_MAX_PACKET_SIZE);

	dbg_desc.bDebugInEndpoint = i_desc.bEndpointAddress;
	dbg_desc.bDebugOutEndpoint = o_desc.bEndpointAddress;

#ifdef CONFIG_USB_G_DBGP_SERIAL
	dbgp.serial->in = dbgp.i_ep;
	dbgp.serial->out = dbgp.o_ep;

	dbgp.serial->in->desc = &i_desc;
	dbgp.serial->out->desc = &o_desc;
#endif

	return 0;

fail_2:
	dbgp.i_ep->driver_data = NULL;
fail_1:
	dev_dbg(&dbgp.gadget->dev, "ep config: failure (%d)\n", stp);
	return -ENODEV;
}

static int __init dbgp_bind(struct usb_gadget *gadget,
		struct usb_gadget_driver *driver)
{
	int err, stp;

	dbgp.gadget = gadget;

	dbgp.req = usb_ep_alloc_request(gadget->ep0, GFP_KERNEL);
	if (!dbgp.req) {
		err = -ENOMEM;
		stp = 1;
		goto fail;
	}

	dbgp.req->buf = kmalloc(DBGP_REQ_EP0_LEN, GFP_KERNEL);
	if (!dbgp.req->buf) {
		err = -ENOMEM;
		stp = 2;
		goto fail;
	}

	dbgp.req->length = DBGP_REQ_EP0_LEN;
	gadget->ep0->driver_data = gadget;

#ifdef CONFIG_USB_G_DBGP_SERIAL
	dbgp.serial = kzalloc(sizeof(struct gserial), GFP_KERNEL);
	if (!dbgp.serial) {
		stp = 3;
		err = -ENOMEM;
		goto fail;
	}

	if (gserial_alloc_line(&tty_line)) {
		stp = 4;
		err = -ENODEV;
		goto fail;
	}
#endif

	err = dbgp_configure_endpoints(gadget);
	if (err < 0) {
		stp = 5;
		goto fail;
	}

	dev_dbg(&dbgp.gadget->dev, "bind: success\n");
	return 0;

fail:
	dev_dbg(&gadget->dev, "bind: failure (%d:%d)\n", stp, err);
	dbgp_unbind(gadget);
	return err;
}

static void dbgp_setup_complete(struct usb_ep *ep,
				struct usb_request *req)
{
	dev_dbg(&dbgp.gadget->dev, "setup complete: %d, %d/%d\n",
		req->status, req->actual, req->length);
}

static int dbgp_setup(struct usb_gadget *gadget,
		      const struct usb_ctrlrequest *ctrl)
{
	struct usb_request *req = dbgp.req;
	u8 request = ctrl->bRequest;
	u16 value = le16_to_cpu(ctrl->wValue);
	u16 length = le16_to_cpu(ctrl->wLength);
	int err = -EOPNOTSUPP;
	void *data = NULL;
	u16 len = 0;

	gadget->ep0->driver_data = gadget;

	if (request == USB_REQ_GET_DESCRIPTOR) {
		switch (value>>8) {
		case USB_DT_DEVICE:
			dev_dbg(&dbgp.gadget->dev, "setup: desc device\n");
			len = sizeof device_desc;
			data = &device_desc;
			device_desc.bMaxPacketSize0 = gadget->ep0->maxpacket;
			break;
		case USB_DT_DEBUG:
			dev_dbg(&dbgp.gadget->dev, "setup: desc debug\n");
			len = sizeof dbg_desc;
			data = &dbg_desc;
			break;
		default:
			goto fail;
		}
		err = 0;
	} else if (request == USB_REQ_SET_FEATURE &&
		   value == USB_DEVICE_DEBUG_MODE) {
		dev_dbg(&dbgp.gadget->dev, "setup: feat debug\n");
#ifdef CONFIG_USB_G_DBGP_PRINTK
		err = dbgp_enable_ep();
#else
		err = dbgp_configure_endpoints(gadget);
		if (err < 0) {
			goto fail;
		}
		err = gserial_connect(dbgp.serial, tty_line);
#endif
		if (err < 0)
			goto fail;
	} else
		goto fail;

	req->length = min(length, len);
	req->zero = len < req->length;
	if (data && req->length)
		memcpy(req->buf, data, req->length);

	req->complete = dbgp_setup_complete;
	return usb_ep_queue(gadget->ep0, req, GFP_ATOMIC);

fail:
	dev_dbg(&dbgp.gadget->dev,
		"setup: failure req %x v %x\n", request, value);
	return err;
}

static __refdata struct usb_gadget_driver dbgp_driver = {
	.function = "dbgp",
	.max_speed = USB_SPEED_HIGH,
	.bind = dbgp_bind,
	.unbind = dbgp_unbind,
	.setup = dbgp_setup,
	.reset = dbgp_disconnect,
	.disconnect = dbgp_disconnect,
	.driver	= {
		.owner = THIS_MODULE,
		.name = "dbgp"
	},
};

static int __init dbgp_init(void)
{
	return usb_gadget_probe_driver(&dbgp_driver);
}

static void __exit dbgp_exit(void)
{
	usb_gadget_unregister_driver(&dbgp_driver);
#ifdef CONFIG_USB_G_DBGP_SERIAL
	gserial_free_line(tty_line);
#endif
}

MODULE_AUTHOR("Stephane Duverger");
MODULE_LICENSE("GPL");
module_init(dbgp_init);
module_exit(dbgp_exit);