diff options
Diffstat (limited to 'drivers/usb/gadget/legacy/dbgp.c')
| -rw-r--r-- | drivers/usb/gadget/legacy/dbgp.c | 439 |
1 files changed, 439 insertions, 0 deletions
diff --git a/drivers/usb/gadget/legacy/dbgp.c b/drivers/usb/gadget/legacy/dbgp.c new file mode 100644 index 000000000..6bcbad382 --- /dev/null +++ b/drivers/usb/gadget/legacy/dbgp.c @@ -0,0 +1,439 @@ +// SPDX-License-Identifier: GPL-2.0 +/* + * 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 = cpu_to_le16(0x0200), + .bDeviceClass = USB_CLASS_VENDOR_SPEC, + .idVendor = cpu_to_le16(DRIVER_VENDOR_ID), + .idProduct = 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) +{ + usb_ep_disable(ep); +} + +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 = kzalloc(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); + 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; + } +} + +#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; + } + + i_desc.wMaxPacketSize = + cpu_to_le16(USB_DEBUG_MAX_PACKET_SIZE); + + dbgp.o_ep = usb_ep_autoconfig(gadget, &o_desc); + if (!dbgp.o_ep) { + stp = 2; + goto fail_1; + } + + o_desc.wMaxPacketSize = + 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_1: + dev_dbg(&dbgp.gadget->dev, "ep config: failure (%d)\n", stp); + return -ENODEV; +} + +static int 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; + +#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; + + if (length > DBGP_REQ_LEN) { + if (ctrl->bRequestType & USB_DIR_IN) { + /* Cast away the const, we are going to overwrite on purpose. */ + __le16 *temp = (__le16 *)&ctrl->wLength; + + *temp = cpu_to_le16(DBGP_REQ_LEN); + length = DBGP_REQ_LEN; + } else { + return err; + } + } + + + 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 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); |