/*
* zero.c -- Gadget Zero, for USB development
*
* Copyright (C) 2003-2008 David Brownell
* Copyright (C) 2008 by Nokia Corporation
*
* This program is free software; you can redistribute it and/or modify
* it under the terms of the GNU General Public License as published by
* the Free Software Foundation; either version 2 of the License, or
* (at your option) any later version.
*/
/*
* Gadget Zero only needs two bulk endpoints, and is an example of how you
* can write a hardware-agnostic gadget driver running inside a USB device.
* Some hardware details are visible, but don't affect most of the driver.
*
* Use it with the Linux host/master side "usbtest" driver to get a basic
* functional test of your device-side usb stack, or with "usb-skeleton".
*
* It supports two similar configurations. One sinks whatever the usb host
* writes, and in return sources zeroes. The other loops whatever the host
* writes back, so the host can read it.
*
* Many drivers will only have one configuration, letting them be much
* simpler if they also don't support high speed operation (like this
* driver does).
*
* Why is *this* driver using two configurations, rather than setting up
* two interfaces with different functions? To help verify that multiple
* configuration infrastucture is working correctly; also, so that it can
* work with low capability USB controllers without four bulk endpoints.
*/
/*
* driver assumes self-powered hardware, and
* has no way for users to trigger remote wakeup.
*/
/* #define VERBOSE_DEBUG */
#include <linux/kernel.h>
#include <linux/slab.h>
#include <linux/device.h>
#include "g_zero.h"
#include "gadget_chips.h"
/*-------------------------------------------------------------------------*/
/*
* Kbuild is not very cooperative with respect to linking separately
* compiled library objects into one module. So for now we won't use
* separate compilation ... ensuring init/exit sections work to shrink
* the runtime footprint, and giving us at least some parts of what
* a "gcc --combine ... part1.c part2.c part3.c ... " build would.
*/
#include "f_sourcesink.c"
#include "f_loopback.c"
/*-------------------------------------------------------------------------*/
USB_GADGET_COMPOSITE_OPTIONS();
#define DRIVER_VERSION "Cinco de Mayo 2008"
static const char longname[] = "Gadget Zero";
unsigned buflen = 4096; /* only used for bulk endpoints */
module_param(buflen, uint, 0);
/*
* Normally the "loopback" configuration is second (index 1) so
* it's not the default. Here's where to change that order, to
* work better with hosts where config changes are problematic or
* controllers (like original superh) that only support one config.
*/
static bool loopdefault = 0;
module_param(loopdefault, bool, S_IRUGO|S_IWUSR);
/*-------------------------------------------------------------------------*/
/* Thanks to NetChip Technologies for donating this product ID.
*
* DO NOT REUSE THESE IDs with a protocol-incompatible driver!! Ever!!
* Instead: allocate your own, using normal USB-IF procedures.
*/
#ifndef CONFIG_USB_ZERO_HNPTEST
#define DRIVER_VENDOR_NUM 0x0525 /* NetChip */
#define DRIVER_PRODUCT_NUM 0xa4a0 /* Linux-USB "Gadget Zero" */
#define DEFAULT_AUTORESUME 0
#else
#define DRIVER_VENDOR_NUM 0x1a0a /* OTG test device IDs */
#define DRIVER_PRODUCT_NUM 0xbadd
#define DEFAULT_AUTORESUME 5
#endif
/* If the optional "autoresume" mode is enabled, it provides good
* functional coverage for the "USBCV" test harness from USB-IF.
* It's always set if OTG mode is enabled.
*/
unsigned autoresume = DEFAULT_AUTORESUME;
module_param(autoresume, uint, S_IRUGO);
MODULE_PARM_DESC(autoresume, "zero, or seconds before remote wakeup");
/*-------------------------------------------------------------------------*/
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_NUM),
.idProduct = cpu_to_le16(DRIVER_PRODUCT_NUM),
.bNumConfigurations = 2,
};
#ifdef CONFIG_USB_OTG
static struct usb_otg_descriptor otg_descriptor = {
.bLength = sizeof otg_descriptor,
.bDescriptorType = USB_DT_OTG,
/* REVISIT SRP-only hardware is possible, although
* it would not be called "OTG" ...
*/
.bmAttributes = USB_OTG_SRP | USB_OTG_HNP,
};
const struct usb_descriptor_header *otg_desc[] = {
(struct usb_descriptor_header *) &otg_descriptor,
NULL,
};
#endif
/* string IDs are assigned dynamically */
/* default serial number takes at least two packets */
static char serial[] = "0123456789.0123456789.0123456789";
static struct usb_string strings_dev[] = {
[USB_GADGET_MANUFACTURER_IDX].s = "",
[USB_GADGET_PRODUCT_IDX].s = longname,
[USB_GADGET_SERIAL_IDX].s = serial,
{ } /* end of list */
};
static struct usb_gadget_strings stringtab_dev = {
.language = 0x0409, /* en-us */
.strings = strings_dev,
};
static struct usb_gadget_strings *dev_strings[] = {
&stringtab_dev,
NULL,
};
/*-------------------------------------------------------------------------*/
struct usb_request *alloc_ep_req(struct usb_ep *ep, int len)
{
struct usb_request *req;
req = usb_ep_alloc_request(ep, GFP_ATOMIC);
if (req) {
if (len)
req->length = len;
else
req->length = buflen;
req->buf = kmalloc(req->length, GFP_ATOMIC);
if (!req->buf) {
usb_ep_free_request(ep, req);
req = NULL;
}
}
return req;
}
void free_ep_req(struct usb_ep *ep, struct usb_request *req)
{
kfree(req->buf);
usb_ep_free_request(ep, req);
}
static void disable_ep(struct usb_composite_dev *cdev, struct usb_ep *ep)
{
int value;
if (ep->driver_data) {
value = usb_ep_disable(ep);
if (value < 0)
DBG(cdev, "disable %s --> %d\n",
ep->name, value);
ep->driver_data = NULL;
}
}
void disable_endpoints(struct usb_composite_dev *cdev,
struct usb_ep *in, struct usb_ep *out,
struct usb_ep *iso_in, struct usb_ep *iso_out)
{
disable_ep(cdev, in);
disable_ep(cdev, out);
if (iso_in)
disable_ep(cdev, iso_in);
if (iso_out)
disable_ep(cdev, iso_out);
}
/*-------------------------------------------------------------------------*/
static struct timer_list autoresume_timer;
static void zero_autoresume(unsigned long _c)
{
struct usb_composite_dev *cdev = (void *)_c;
struct usb_gadget *g = cdev->gadget;
/* unconfigured devices can't issue wakeups */
if (!cdev->config)
return;
/* Normally the host would be woken up for something
* more significant than just a timer firing; likely
* because of some direct user request.
*/
if (g->speed != USB_SPEED_UNKNOWN) {
int status = usb_gadget_wakeup(g);
INFO(cdev, "%s --> %d\n", __func__, status);
}
}
static void zero_suspend(struct usb_composite_dev *cdev)
{
if (cdev->gadget->speed == USB_SPEED_UNKNOWN)
return;
if (autoresume) {
mod_timer(&autoresume_timer, jiffies + (HZ * autoresume));
DBG(cdev, "suspend, wakeup in %d seconds\n", autoresume);
} else
DBG(cdev, "%s\n", __func__);
}
static void zero_resume(struct usb_composite_dev *cdev)
{
DBG(cdev, "%s\n", __func__);
del_timer(&autoresume_timer);
}
/*-------------------------------------------------------------------------*/
static int __init zero_bind(struct usb_composite_dev *cdev)
{
int status;
/* Allocate string descriptor numbers ... note that string
* contents can be overridden by the composite_dev glue.
*/
status = usb_string_ids_tab(cdev, strings_dev);
if (status < 0)
return status;
device_desc.iManufacturer = strings_dev[USB_GADGET_MANUFACTURER_IDX].id;
device_desc.iProduct = strings_dev[USB_GADGET_PRODUCT_IDX].id;
device_desc.iSerialNumber = strings_dev[USB_GADGET_SERIAL_IDX].id;
setup_timer(&autoresume_timer, zero_autoresume, (unsigned long) cdev);
/* Register primary, then secondary configuration. Note that
* SH3 only allows one config...
*/
if (loopdefault) {
loopback_add(cdev, autoresume != 0);
sourcesink_add(cdev, autoresume != 0);
} else {
sourcesink_add(cdev, autoresume != 0);
loopback_add(cdev, autoresume != 0);
}
usb_composite_overwrite_options(cdev, &coverwrite);
INFO(cdev, "%s, version: " DRIVER_VERSION "\n", longname);
return 0;
}
static int zero_unbind(struct usb_composite_dev *cdev)
{
del_timer_sync(&autoresume_timer);
return 0;
}
static __refdata struct usb_composite_driver zero_driver = {
.name = "zero",
.dev = &device_desc,
.strings = dev_strings,
.max_speed = USB_SPEED_SUPER,
.bind = zero_bind,
.unbind = zero_unbind,
.suspend = zero_suspend,
.resume = zero_resume,
};
MODULE_AUTHOR("David Brownell");
MODULE_LICENSE("GPL");
static int __init init(void)
{
return usb_composite_probe(&zero_driver);
}
module_init(init);
static void __exit cleanup(void)
{
usb_composite_unregister(&zero_driver);
}
module_exit(cleanup);
