1 // SPDX-License-Identifier: GPL-2.0
3 * dbgp.c -- EHCI Debug Port device gadget
5 * Copyright (C) 2010 Stephane Duverger
7 * Released under the GPLv2.
10 /* verbose messages */
11 #include <linux/kernel.h>
12 #include <linux/device.h>
13 #include <linux/module.h>
14 #include <linux/usb/ch9.h>
15 #include <linux/usb/gadget.h>
19 #define DRIVER_VENDOR_ID 0x0525 /* NetChip */
20 #define DRIVER_PRODUCT_ID 0xc0de /* undefined */
22 #define USB_DEBUG_MAX_PACKET_SIZE 8
23 #define DBGP_REQ_EP0_LEN 128
24 #define DBGP_REQ_LEN 512
27 struct usb_gadget *gadget;
28 struct usb_request *req;
31 #ifdef CONFIG_USB_G_DBGP_SERIAL
32 struct gserial *serial;
36 static struct usb_device_descriptor device_desc = {
37 .bLength = sizeof device_desc,
38 .bDescriptorType = USB_DT_DEVICE,
39 .bcdUSB = cpu_to_le16(0x0200),
40 .bDeviceClass = USB_CLASS_VENDOR_SPEC,
41 .idVendor = cpu_to_le16(DRIVER_VENDOR_ID),
42 .idProduct = cpu_to_le16(DRIVER_PRODUCT_ID),
43 .bNumConfigurations = 1,
46 static struct usb_debug_descriptor dbg_desc = {
47 .bLength = sizeof dbg_desc,
48 .bDescriptorType = USB_DT_DEBUG,
51 static struct usb_endpoint_descriptor i_desc = {
52 .bLength = USB_DT_ENDPOINT_SIZE,
53 .bDescriptorType = USB_DT_ENDPOINT,
54 .bmAttributes = USB_ENDPOINT_XFER_BULK,
55 .bEndpointAddress = USB_DIR_IN,
58 static struct usb_endpoint_descriptor o_desc = {
59 .bLength = USB_DT_ENDPOINT_SIZE,
60 .bDescriptorType = USB_DT_ENDPOINT,
61 .bmAttributes = USB_ENDPOINT_XFER_BULK,
62 .bEndpointAddress = USB_DIR_OUT,
65 #ifdef CONFIG_USB_G_DBGP_PRINTK
66 static int dbgp_consume(char *buf, unsigned len)
77 printk(KERN_NOTICE "%s%c", buf, c);
81 static void __disable_ep(struct usb_ep *ep)
86 static void dbgp_disable_ep(void)
88 __disable_ep(dbgp.i_ep);
89 __disable_ep(dbgp.o_ep);
92 static void dbgp_complete(struct usb_ep *ep, struct usb_request *req)
96 int status = req->status;
98 if (ep == dbgp.i_ep) {
108 dbgp_consume(req->buf, req->actual);
110 req->length = DBGP_REQ_LEN;
111 err = usb_ep_queue(ep, req, GFP_ATOMIC);
121 usb_ep_free_request(dbgp.o_ep, req);
124 dev_dbg(&dbgp.gadget->dev,
125 "complete: failure (%d:%d) ==> %d\n", stp, err, status);
128 static int dbgp_enable_ep_req(struct usb_ep *ep)
131 struct usb_request *req;
133 req = usb_ep_alloc_request(ep, GFP_KERNEL);
140 req->buf = kzalloc(DBGP_REQ_LEN, GFP_KERNEL);
147 req->complete = dbgp_complete;
148 req->length = DBGP_REQ_LEN;
149 err = usb_ep_queue(ep, req, GFP_ATOMIC);
160 usb_ep_free_request(dbgp.o_ep, req);
162 dev_dbg(&dbgp.gadget->dev,
163 "enable ep req: failure (%d:%d)\n", stp, err);
167 static int __enable_ep(struct usb_ep *ep, struct usb_endpoint_descriptor *desc)
171 err = usb_ep_enable(ep);
175 static int dbgp_enable_ep(void)
179 err = __enable_ep(dbgp.i_ep, &i_desc);
185 err = __enable_ep(dbgp.o_ep, &o_desc);
191 err = dbgp_enable_ep_req(dbgp.o_ep);
200 __disable_ep(dbgp.o_ep);
202 __disable_ep(dbgp.i_ep);
204 dev_dbg(&dbgp.gadget->dev, "enable ep: failure (%d:%d)\n", stp, err);
209 static void dbgp_disconnect(struct usb_gadget *gadget)
211 #ifdef CONFIG_USB_G_DBGP_PRINTK
214 gserial_disconnect(dbgp.serial);
218 static void dbgp_unbind(struct usb_gadget *gadget)
220 #ifdef CONFIG_USB_G_DBGP_SERIAL
225 kfree(dbgp.req->buf);
226 usb_ep_free_request(gadget->ep0, dbgp.req);
231 #ifdef CONFIG_USB_G_DBGP_SERIAL
232 static unsigned char tty_line;
235 static int dbgp_configure_endpoints(struct usb_gadget *gadget)
239 usb_ep_autoconfig_reset(gadget);
241 dbgp.i_ep = usb_ep_autoconfig(gadget, &i_desc);
247 i_desc.wMaxPacketSize =
248 cpu_to_le16(USB_DEBUG_MAX_PACKET_SIZE);
250 dbgp.o_ep = usb_ep_autoconfig(gadget, &o_desc);
256 o_desc.wMaxPacketSize =
257 cpu_to_le16(USB_DEBUG_MAX_PACKET_SIZE);
259 dbg_desc.bDebugInEndpoint = i_desc.bEndpointAddress;
260 dbg_desc.bDebugOutEndpoint = o_desc.bEndpointAddress;
262 #ifdef CONFIG_USB_G_DBGP_SERIAL
263 dbgp.serial->in = dbgp.i_ep;
264 dbgp.serial->out = dbgp.o_ep;
266 dbgp.serial->in->desc = &i_desc;
267 dbgp.serial->out->desc = &o_desc;
273 dev_dbg(&dbgp.gadget->dev, "ep config: failure (%d)\n", stp);
277 static int dbgp_bind(struct usb_gadget *gadget,
278 struct usb_gadget_driver *driver)
282 dbgp.gadget = gadget;
284 dbgp.req = usb_ep_alloc_request(gadget->ep0, GFP_KERNEL);
291 dbgp.req->buf = kmalloc(DBGP_REQ_EP0_LEN, GFP_KERNEL);
292 if (!dbgp.req->buf) {
298 dbgp.req->length = DBGP_REQ_EP0_LEN;
300 #ifdef CONFIG_USB_G_DBGP_SERIAL
301 dbgp.serial = kzalloc(sizeof(struct gserial), GFP_KERNEL);
308 if (gserial_alloc_line(&tty_line)) {
315 err = dbgp_configure_endpoints(gadget);
321 dev_dbg(&dbgp.gadget->dev, "bind: success\n");
325 dev_dbg(&gadget->dev, "bind: failure (%d:%d)\n", stp, err);
330 static void dbgp_setup_complete(struct usb_ep *ep,
331 struct usb_request *req)
333 dev_dbg(&dbgp.gadget->dev, "setup complete: %d, %d/%d\n",
334 req->status, req->actual, req->length);
337 static int dbgp_setup(struct usb_gadget *gadget,
338 const struct usb_ctrlrequest *ctrl)
340 struct usb_request *req = dbgp.req;
341 u8 request = ctrl->bRequest;
342 u16 value = le16_to_cpu(ctrl->wValue);
343 u16 length = le16_to_cpu(ctrl->wLength);
344 int err = -EOPNOTSUPP;
348 if (length > DBGP_REQ_LEN) {
349 if (ctrl->bRequestType & USB_DIR_IN) {
350 /* Cast away the const, we are going to overwrite on purpose. */
351 __le16 *temp = (__le16 *)&ctrl->wLength;
353 *temp = cpu_to_le16(DBGP_REQ_LEN);
354 length = DBGP_REQ_LEN;
361 if (request == USB_REQ_GET_DESCRIPTOR) {
364 dev_dbg(&dbgp.gadget->dev, "setup: desc device\n");
365 len = sizeof device_desc;
367 device_desc.bMaxPacketSize0 = gadget->ep0->maxpacket;
370 dev_dbg(&dbgp.gadget->dev, "setup: desc debug\n");
371 len = sizeof dbg_desc;
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();
384 err = dbgp_configure_endpoints(gadget);
388 err = gserial_connect(dbgp.serial, tty_line);
395 req->length = min(length, len);
396 req->zero = len < req->length;
397 if (data && req->length)
398 memcpy(req->buf, data, req->length);
400 req->complete = dbgp_setup_complete;
401 return usb_ep_queue(gadget->ep0, req, GFP_ATOMIC);
404 dev_dbg(&dbgp.gadget->dev,
405 "setup: failure req %x v %x\n", request, value);
409 static struct usb_gadget_driver dbgp_driver = {
411 .max_speed = USB_SPEED_HIGH,
413 .unbind = dbgp_unbind,
415 .reset = dbgp_disconnect,
416 .disconnect = dbgp_disconnect,
418 .owner = THIS_MODULE,
423 static int __init dbgp_init(void)
425 return usb_gadget_probe_driver(&dbgp_driver);
428 static void __exit dbgp_exit(void)
430 usb_gadget_unregister_driver(&dbgp_driver);
431 #ifdef CONFIG_USB_G_DBGP_SERIAL
432 gserial_free_line(tty_line);
436 MODULE_AUTHOR("Stephane Duverger");
437 MODULE_LICENSE("GPL");
438 module_init(dbgp_init);
439 module_exit(dbgp_exit);