diff options
Diffstat (limited to 'drivers/usb/gadget/zero.c')
-rw-r--r-- | drivers/usb/gadget/zero.c | 353 |
1 files changed, 353 insertions, 0 deletions
diff --git a/drivers/usb/gadget/zero.c b/drivers/usb/gadget/zero.c new file mode 100644 index 00000000..31d34832 --- /dev/null +++ b/drivers/usb/gadget/zero.c @@ -0,0 +1,353 @@ +/* + * 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/utsname.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 "composite.c" +#include "usbstring.c" +#include "config.c" +#include "epautoconf.c" + +#include "f_sourcesink.c" +#include "f_loopback.c" + +/*-------------------------------------------------------------------------*/ + +#define DRIVER_VERSION "Cinco de Mayo 2008" + +static const char longname[] = "Gadget Zero"; + +unsigned buflen = 4096; +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 */ + +#define STRING_MANUFACTURER_IDX 0 +#define STRING_PRODUCT_IDX 1 +#define STRING_SERIAL_IDX 2 + +static char manufacturer[50]; + +/* default serial number takes at least two packets */ +static char serial[] = "0123456789.0123456789.0123456789"; + +static struct usb_string strings_dev[] = { + [STRING_MANUFACTURER_IDX].s = manufacturer, + [STRING_PRODUCT_IDX].s = longname, + [STRING_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) +{ + struct usb_request *req; + + req = usb_ep_alloc_request(ep, GFP_ATOMIC); + if (req) { + req->length = buflen; + req->buf = kmalloc(buflen, 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) +{ + disable_ep(cdev, in); + disable_ep(cdev, 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 gcnum; + struct usb_gadget *gadget = cdev->gadget; + int id; + + /* Allocate string descriptor numbers ... note that string + * contents can be overridden by the composite_dev glue. + */ + id = usb_string_id(cdev); + if (id < 0) + return id; + strings_dev[STRING_MANUFACTURER_IDX].id = id; + device_desc.iManufacturer = id; + + id = usb_string_id(cdev); + if (id < 0) + return id; + strings_dev[STRING_PRODUCT_IDX].id = id; + device_desc.iProduct = id; + + id = usb_string_id(cdev); + if (id < 0) + return id; + strings_dev[STRING_SERIAL_IDX].id = id; + device_desc.iSerialNumber = 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); + } + + gcnum = usb_gadget_controller_number(gadget); + if (gcnum >= 0) + device_desc.bcdDevice = cpu_to_le16(0x0200 + gcnum); + else { + /* gadget zero is so simple (for now, no altsettings) that + * it SHOULD NOT have problems with bulk-capable hardware. + * so just warn about unrcognized controllers -- don't panic. + * + * things like configuration and altsetting numbering + * can need hardware-specific attention though. + */ + pr_warning("%s: controller '%s' not recognized\n", + longname, gadget->name); + device_desc.bcdDevice = cpu_to_le16(0x9999); + } + + + INFO(cdev, "%s, version: " DRIVER_VERSION "\n", longname); + + snprintf(manufacturer, sizeof manufacturer, "%s %s with %s", + init_utsname()->sysname, init_utsname()->release, + gadget->name); + + return 0; +} + +static int zero_unbind(struct usb_composite_dev *cdev) +{ + del_timer_sync(&autoresume_timer); + return 0; +} + +static struct usb_composite_driver zero_driver = { + .name = "zero", + .dev = &device_desc, + .strings = dev_strings, + .max_speed = USB_SPEED_SUPER, + .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, zero_bind); +} +module_init(init); + +static void __exit cleanup(void) +{ + usb_composite_unregister(&zero_driver); +} +module_exit(cleanup); |