1/* 2 * dbgp.c -- EHCI Debug Port device gadget 3 * 4 * Copyright (C) 2010 Stephane Duverger 5 * 6 * Released under the GPLv2. 7 */ 8 9/* verbose messages */ 10#include <linux/kernel.h> 11#include <linux/device.h> 12#include <linux/module.h> 13#include <linux/usb/ch9.h> 14#include <linux/usb/gadget.h> 15 16/* See comments in "zero.c" */ 17#include "epautoconf.c" 18 19#ifdef CONFIG_USB_G_DBGP_SERIAL 20#include "u_serial.c" 21#endif 22 23#define DRIVER_VENDOR_ID 0x0525 /* NetChip */ 24#define DRIVER_PRODUCT_ID 0xc0de /* undefined */ 25 26#define USB_DEBUG_MAX_PACKET_SIZE 8 27#define DBGP_REQ_EP0_LEN 128 28#define DBGP_REQ_LEN 512 29 30static struct dbgp { 31 struct usb_gadget *gadget; 32 struct usb_request *req; 33 struct usb_ep *i_ep; 34 struct usb_ep *o_ep; 35#ifdef CONFIG_USB_G_DBGP_SERIAL 36 struct gserial *serial; 37#endif 38} dbgp; 39 40static struct usb_device_descriptor device_desc = { 41 .bLength = sizeof device_desc, 42 .bDescriptorType = USB_DT_DEVICE, 43 .bcdUSB = __constant_cpu_to_le16(0x0200), 44 .bDeviceClass = USB_CLASS_VENDOR_SPEC, 45 .idVendor = __constant_cpu_to_le16(DRIVER_VENDOR_ID), 46 .idProduct = __constant_cpu_to_le16(DRIVER_PRODUCT_ID), 47 .bNumConfigurations = 1, 48}; 49 50static struct usb_debug_descriptor dbg_desc = { 51 .bLength = sizeof dbg_desc, 52 .bDescriptorType = USB_DT_DEBUG, 53}; 54 55static struct usb_endpoint_descriptor i_desc = { 56 .bLength = USB_DT_ENDPOINT_SIZE, 57 .bDescriptorType = USB_DT_ENDPOINT, 58 .bmAttributes = USB_ENDPOINT_XFER_BULK, 59 .bEndpointAddress = USB_DIR_IN, 60}; 61 62static struct usb_endpoint_descriptor o_desc = { 63 .bLength = USB_DT_ENDPOINT_SIZE, 64 .bDescriptorType = USB_DT_ENDPOINT, 65 .bmAttributes = USB_ENDPOINT_XFER_BULK, 66 .bEndpointAddress = USB_DIR_OUT, 67}; 68 69#ifdef CONFIG_USB_G_DBGP_PRINTK 70static int dbgp_consume(char *buf, unsigned len) 71{ 72 char c; 73 74 if (!len) 75 return 0; 76 77 c = buf[len-1]; 78 if (c != 0) 79 buf[len-1] = 0; 80 81 printk(KERN_NOTICE "%s%c", buf, c); 82 return 0; 83} 84 85static void __disable_ep(struct usb_ep *ep) 86{ 87 if (ep && ep->driver_data == dbgp.gadget) { 88 usb_ep_disable(ep); 89 ep->driver_data = NULL; 90 } 91} 92 93static void dbgp_disable_ep(void) 94{ 95 __disable_ep(dbgp.i_ep); 96 __disable_ep(dbgp.o_ep); 97} 98 99static void dbgp_complete(struct usb_ep *ep, struct usb_request *req) 100{ 101 int stp; 102 int err = 0; 103 int status = req->status; 104 105 if (ep == dbgp.i_ep) { 106 stp = 1; 107 goto fail; 108 } 109 110 if (status != 0) { 111 stp = 2; 112 goto release_req; 113 } 114 115 dbgp_consume(req->buf, req->actual); 116 117 req->length = DBGP_REQ_LEN; 118 err = usb_ep_queue(ep, req, GFP_ATOMIC); 119 if (err < 0) { 120 stp = 3; 121 goto release_req; 122 } 123 124 return; 125 126release_req: 127 kfree(req->buf); 128 usb_ep_free_request(dbgp.o_ep, req); 129 dbgp_disable_ep(); 130fail: 131 dev_dbg(&dbgp.gadget->dev, 132 "complete: failure (%d:%d) ==> %d\n", stp, err, status); 133} 134 135static int dbgp_enable_ep_req(struct usb_ep *ep) 136{ 137 int err, stp; 138 struct usb_request *req; 139 140 req = usb_ep_alloc_request(ep, GFP_KERNEL); 141 if (!req) { 142 err = -ENOMEM; 143 stp = 1; 144 goto fail_1; 145 } 146 147 req->buf = kmalloc(DBGP_REQ_LEN, GFP_KERNEL); 148 if (!req->buf) { 149 err = -ENOMEM; 150 stp = 2; 151 goto fail_2; 152 } 153 154 req->complete = dbgp_complete; 155 req->length = DBGP_REQ_LEN; 156 err = usb_ep_queue(ep, req, GFP_ATOMIC); 157 if (err < 0) { 158 stp = 3; 159 goto fail_3; 160 } 161 162 return 0; 163 164fail_3: 165 kfree(req->buf); 166fail_2: 167 usb_ep_free_request(dbgp.o_ep, req); 168fail_1: 169 dev_dbg(&dbgp.gadget->dev, 170 "enable ep req: failure (%d:%d)\n", stp, err); 171 return err; 172} 173 174static int __enable_ep(struct usb_ep *ep, struct usb_endpoint_descriptor *desc) 175{ 176 int err; 177 ep->desc = desc; 178 err = usb_ep_enable(ep); 179 ep->driver_data = dbgp.gadget; 180 return err; 181} 182 183static int dbgp_enable_ep(void) 184{ 185 int err, stp; 186 187 err = __enable_ep(dbgp.i_ep, &i_desc); 188 if (err < 0) { 189 stp = 1; 190 goto fail_1; 191 } 192 193 err = __enable_ep(dbgp.o_ep, &o_desc); 194 if (err < 0) { 195 stp = 2; 196 goto fail_2; 197 } 198 199 err = dbgp_enable_ep_req(dbgp.o_ep); 200 if (err < 0) { 201 stp = 3; 202 goto fail_3; 203 } 204 205 return 0; 206 207fail_3: 208 __disable_ep(dbgp.o_ep); 209fail_2: 210 __disable_ep(dbgp.i_ep); 211fail_1: 212 dev_dbg(&dbgp.gadget->dev, "enable ep: failure (%d:%d)\n", stp, err); 213 return err; 214} 215#endif 216 217static void dbgp_disconnect(struct usb_gadget *gadget) 218{ 219#ifdef CONFIG_USB_G_DBGP_PRINTK 220 dbgp_disable_ep(); 221#else 222 gserial_disconnect(dbgp.serial); 223#endif 224} 225 226static void dbgp_unbind(struct usb_gadget *gadget) 227{ 228#ifdef CONFIG_USB_G_DBGP_SERIAL 229 kfree(dbgp.serial); 230#endif 231 if (dbgp.req) { 232 kfree(dbgp.req->buf); 233 usb_ep_free_request(gadget->ep0, dbgp.req); 234 } 235 236 gadget->ep0->driver_data = NULL; 237} 238 239static int __init dbgp_configure_endpoints(struct usb_gadget *gadget) 240{ 241 int stp; 242 243 usb_ep_autoconfig_reset(gadget); 244 245 dbgp.i_ep = usb_ep_autoconfig(gadget, &i_desc); 246 if (!dbgp.i_ep) { 247 stp = 1; 248 goto fail_1; 249 } 250 251 dbgp.i_ep->driver_data = gadget; 252 i_desc.wMaxPacketSize = 253 __constant_cpu_to_le16(USB_DEBUG_MAX_PACKET_SIZE); 254 255 dbgp.o_ep = usb_ep_autoconfig(gadget, &o_desc); 256 if (!dbgp.o_ep) { 257 dbgp.i_ep->driver_data = NULL; 258 stp = 2; 259 goto fail_2; 260 } 261 262 dbgp.o_ep->driver_data = gadget; 263 o_desc.wMaxPacketSize = 264 __constant_cpu_to_le16(USB_DEBUG_MAX_PACKET_SIZE); 265 266 dbg_desc.bDebugInEndpoint = i_desc.bEndpointAddress; 267 dbg_desc.bDebugOutEndpoint = o_desc.bEndpointAddress; 268 269#ifdef CONFIG_USB_G_DBGP_SERIAL 270 dbgp.serial->in = dbgp.i_ep; 271 dbgp.serial->out = dbgp.o_ep; 272 273 dbgp.serial->in->desc = &i_desc; 274 dbgp.serial->out->desc = &o_desc; 275 276 if (gserial_setup(gadget, 1) < 0) { 277 stp = 3; 278 goto fail_3; 279 } 280 281 return 0; 282 283fail_3: 284 dbgp.o_ep->driver_data = NULL; 285#else 286 return 0; 287#endif 288fail_2: 289 dbgp.i_ep->driver_data = NULL; 290fail_1: 291 dev_dbg(&dbgp.gadget->dev, "ep config: failure (%d)\n", stp); 292 return -ENODEV; 293} 294 295static int __init dbgp_bind(struct usb_gadget *gadget) 296{ 297 int err, stp; 298 299 dbgp.gadget = gadget; 300 301 dbgp.req = usb_ep_alloc_request(gadget->ep0, GFP_KERNEL); 302 if (!dbgp.req) { 303 err = -ENOMEM; 304 stp = 1; 305 goto fail; 306 } 307 308 dbgp.req->buf = kmalloc(DBGP_REQ_EP0_LEN, GFP_KERNEL); 309 if (!dbgp.req->buf) { 310 err = -ENOMEM; 311 stp = 2; 312 goto fail; 313 } 314 315 dbgp.req->length = DBGP_REQ_EP0_LEN; 316 gadget->ep0->driver_data = gadget; 317 318#ifdef CONFIG_USB_G_DBGP_SERIAL 319 dbgp.serial = kzalloc(sizeof(struct gserial), GFP_KERNEL); 320 if (!dbgp.serial) { 321 stp = 3; 322 err = -ENOMEM; 323 goto fail; 324 } 325#endif 326 err = dbgp_configure_endpoints(gadget); 327 if (err < 0) { 328 stp = 4; 329 goto fail; 330 } 331 332 dev_dbg(&dbgp.gadget->dev, "bind: success\n"); 333 return 0; 334 335fail: 336 dev_dbg(&gadget->dev, "bind: failure (%d:%d)\n", stp, err); 337 dbgp_unbind(gadget); 338 return err; 339} 340 341static void dbgp_setup_complete(struct usb_ep *ep, 342 struct usb_request *req) 343{ 344 dev_dbg(&dbgp.gadget->dev, "setup complete: %d, %d/%d\n", 345 req->status, req->actual, req->length); 346} 347 348static int dbgp_setup(struct usb_gadget *gadget, 349 const struct usb_ctrlrequest *ctrl) 350{ 351 struct usb_request *req = dbgp.req; 352 u8 request = ctrl->bRequest; 353 u16 value = le16_to_cpu(ctrl->wValue); 354 u16 length = le16_to_cpu(ctrl->wLength); 355 int err = -EOPNOTSUPP; 356 void *data = NULL; 357 u16 len = 0; 358 359 gadget->ep0->driver_data = gadget; 360 361 if (request == USB_REQ_GET_DESCRIPTOR) { 362 switch (value>>8) { 363 case USB_DT_DEVICE: 364 dev_dbg(&dbgp.gadget->dev, "setup: desc device\n"); 365 len = sizeof device_desc; 366 data = &device_desc; 367 device_desc.bMaxPacketSize0 = gadget->ep0->maxpacket; 368 break; 369 case USB_DT_DEBUG: 370 dev_dbg(&dbgp.gadget->dev, "setup: desc debug\n"); 371 len = sizeof dbg_desc; 372 data = &dbg_desc; 373 break; 374 default: 375 goto fail; 376 } 377 err = 0; 378 } else if (request == USB_REQ_SET_FEATURE && 379 value == USB_DEVICE_DEBUG_MODE) { 380 dev_dbg(&dbgp.gadget->dev, "setup: feat debug\n"); 381#ifdef CONFIG_USB_G_DBGP_PRINTK 382 err = dbgp_enable_ep(); 383#else 384 err = gserial_connect(dbgp.serial, 0); 385#endif 386 if (err < 0) 387 goto fail; 388 } else 389 goto fail; 390 391 req->length = min(length, len); 392 req->zero = len < req->length; 393 if (data && req->length) 394 memcpy(req->buf, data, req->length); 395 396 req->complete = dbgp_setup_complete; 397 return usb_ep_queue(gadget->ep0, req, GFP_ATOMIC); 398 399fail: 400 dev_dbg(&dbgp.gadget->dev, 401 "setup: failure req %x v %x\n", request, value); 402 return err; 403} 404 405static struct usb_gadget_driver dbgp_driver = { 406 .function = "dbgp", 407 .max_speed = USB_SPEED_HIGH, 408 .unbind = dbgp_unbind, 409 .setup = dbgp_setup, 410 .disconnect = dbgp_disconnect, 411 .driver = { 412 .owner = THIS_MODULE, 413 .name = "dbgp" 414 }, 415}; 416 417static int __init dbgp_init(void) 418{ 419 return usb_gadget_probe_driver(&dbgp_driver, dbgp_bind); 420} 421 422static void __exit dbgp_exit(void) 423{ 424 usb_gadget_unregister_driver(&dbgp_driver); 425#ifdef CONFIG_USB_G_DBGP_SERIAL 426 gserial_cleanup(); 427#endif 428} 429 430MODULE_AUTHOR("Stephane Duverger"); 431MODULE_LICENSE("GPL"); 432module_init(dbgp_init); 433module_exit(dbgp_exit); 434