From 57f0f512b273f60d52568b8c6b77e17f5636edc0 Mon Sep 17 00:00:00 2001 From: André Fabian Silva Delgado Date: Wed, 5 Aug 2015 17:04:01 -0300 Subject: Initial import --- drivers/usb/gadget/function/f_loopback.c | 568 +++++++++++++++++++++++++++++++ 1 file changed, 568 insertions(+) create mode 100644 drivers/usb/gadget/function/f_loopback.c (limited to 'drivers/usb/gadget/function/f_loopback.c') diff --git a/drivers/usb/gadget/function/f_loopback.c b/drivers/usb/gadget/function/f_loopback.c new file mode 100644 index 000000000..39f49f1ad --- /dev/null +++ b/drivers/usb/gadget/function/f_loopback.c @@ -0,0 +1,568 @@ +/* + * f_loopback.c - USB peripheral loopback configuration driver + * + * 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. + */ + +/* #define VERBOSE_DEBUG */ + +#include +#include +#include +#include +#include +#include + +#include "g_zero.h" +#include "u_f.h" + +/* + * LOOPBACK FUNCTION ... a testing vehicle for USB peripherals, + * + * This takes messages of various sizes written OUT to a device, and loops + * them back so they can be read IN from it. It has been used by certain + * test applications. It supports limited testing of data queueing logic. + * + * + * This is currently packaged as a configuration driver, which can't be + * combined with other functions to make composite devices. However, it + * can be combined with other independent configurations. + */ +struct f_loopback { + struct usb_function function; + + struct usb_ep *in_ep; + struct usb_ep *out_ep; +}; + +static inline struct f_loopback *func_to_loop(struct usb_function *f) +{ + return container_of(f, struct f_loopback, function); +} + +static unsigned qlen; +static unsigned buflen; + +/*-------------------------------------------------------------------------*/ + +static struct usb_interface_descriptor loopback_intf = { + .bLength = sizeof loopback_intf, + .bDescriptorType = USB_DT_INTERFACE, + + .bNumEndpoints = 2, + .bInterfaceClass = USB_CLASS_VENDOR_SPEC, + /* .iInterface = DYNAMIC */ +}; + +/* full speed support: */ + +static struct usb_endpoint_descriptor fs_loop_source_desc = { + .bLength = USB_DT_ENDPOINT_SIZE, + .bDescriptorType = USB_DT_ENDPOINT, + + .bEndpointAddress = USB_DIR_IN, + .bmAttributes = USB_ENDPOINT_XFER_BULK, +}; + +static struct usb_endpoint_descriptor fs_loop_sink_desc = { + .bLength = USB_DT_ENDPOINT_SIZE, + .bDescriptorType = USB_DT_ENDPOINT, + + .bEndpointAddress = USB_DIR_OUT, + .bmAttributes = USB_ENDPOINT_XFER_BULK, +}; + +static struct usb_descriptor_header *fs_loopback_descs[] = { + (struct usb_descriptor_header *) &loopback_intf, + (struct usb_descriptor_header *) &fs_loop_sink_desc, + (struct usb_descriptor_header *) &fs_loop_source_desc, + NULL, +}; + +/* high speed support: */ + +static struct usb_endpoint_descriptor hs_loop_source_desc = { + .bLength = USB_DT_ENDPOINT_SIZE, + .bDescriptorType = USB_DT_ENDPOINT, + + .bmAttributes = USB_ENDPOINT_XFER_BULK, + .wMaxPacketSize = cpu_to_le16(512), +}; + +static struct usb_endpoint_descriptor hs_loop_sink_desc = { + .bLength = USB_DT_ENDPOINT_SIZE, + .bDescriptorType = USB_DT_ENDPOINT, + + .bmAttributes = USB_ENDPOINT_XFER_BULK, + .wMaxPacketSize = cpu_to_le16(512), +}; + +static struct usb_descriptor_header *hs_loopback_descs[] = { + (struct usb_descriptor_header *) &loopback_intf, + (struct usb_descriptor_header *) &hs_loop_source_desc, + (struct usb_descriptor_header *) &hs_loop_sink_desc, + NULL, +}; + +/* super speed support: */ + +static struct usb_endpoint_descriptor ss_loop_source_desc = { + .bLength = USB_DT_ENDPOINT_SIZE, + .bDescriptorType = USB_DT_ENDPOINT, + + .bmAttributes = USB_ENDPOINT_XFER_BULK, + .wMaxPacketSize = cpu_to_le16(1024), +}; + +static struct usb_ss_ep_comp_descriptor ss_loop_source_comp_desc = { + .bLength = USB_DT_SS_EP_COMP_SIZE, + .bDescriptorType = USB_DT_SS_ENDPOINT_COMP, + .bMaxBurst = 0, + .bmAttributes = 0, + .wBytesPerInterval = 0, +}; + +static struct usb_endpoint_descriptor ss_loop_sink_desc = { + .bLength = USB_DT_ENDPOINT_SIZE, + .bDescriptorType = USB_DT_ENDPOINT, + + .bmAttributes = USB_ENDPOINT_XFER_BULK, + .wMaxPacketSize = cpu_to_le16(1024), +}; + +static struct usb_ss_ep_comp_descriptor ss_loop_sink_comp_desc = { + .bLength = USB_DT_SS_EP_COMP_SIZE, + .bDescriptorType = USB_DT_SS_ENDPOINT_COMP, + .bMaxBurst = 0, + .bmAttributes = 0, + .wBytesPerInterval = 0, +}; + +static struct usb_descriptor_header *ss_loopback_descs[] = { + (struct usb_descriptor_header *) &loopback_intf, + (struct usb_descriptor_header *) &ss_loop_source_desc, + (struct usb_descriptor_header *) &ss_loop_source_comp_desc, + (struct usb_descriptor_header *) &ss_loop_sink_desc, + (struct usb_descriptor_header *) &ss_loop_sink_comp_desc, + NULL, +}; + +/* function-specific strings: */ + +static struct usb_string strings_loopback[] = { + [0].s = "loop input to output", + { } /* end of list */ +}; + +static struct usb_gadget_strings stringtab_loop = { + .language = 0x0409, /* en-us */ + .strings = strings_loopback, +}; + +static struct usb_gadget_strings *loopback_strings[] = { + &stringtab_loop, + NULL, +}; + +/*-------------------------------------------------------------------------*/ + +static int loopback_bind(struct usb_configuration *c, struct usb_function *f) +{ + struct usb_composite_dev *cdev = c->cdev; + struct f_loopback *loop = func_to_loop(f); + int id; + int ret; + + /* allocate interface ID(s) */ + id = usb_interface_id(c, f); + if (id < 0) + return id; + loopback_intf.bInterfaceNumber = id; + + id = usb_string_id(cdev); + if (id < 0) + return id; + strings_loopback[0].id = id; + loopback_intf.iInterface = id; + + /* allocate endpoints */ + + loop->in_ep = usb_ep_autoconfig(cdev->gadget, &fs_loop_source_desc); + if (!loop->in_ep) { +autoconf_fail: + ERROR(cdev, "%s: can't autoconfigure on %s\n", + f->name, cdev->gadget->name); + return -ENODEV; + } + loop->in_ep->driver_data = cdev; /* claim */ + + loop->out_ep = usb_ep_autoconfig(cdev->gadget, &fs_loop_sink_desc); + if (!loop->out_ep) + goto autoconf_fail; + loop->out_ep->driver_data = cdev; /* claim */ + + /* support high speed hardware */ + hs_loop_source_desc.bEndpointAddress = + fs_loop_source_desc.bEndpointAddress; + hs_loop_sink_desc.bEndpointAddress = fs_loop_sink_desc.bEndpointAddress; + + /* support super speed hardware */ + ss_loop_source_desc.bEndpointAddress = + fs_loop_source_desc.bEndpointAddress; + ss_loop_sink_desc.bEndpointAddress = fs_loop_sink_desc.bEndpointAddress; + + ret = usb_assign_descriptors(f, fs_loopback_descs, hs_loopback_descs, + ss_loopback_descs); + if (ret) + return ret; + + DBG(cdev, "%s speed %s: IN/%s, OUT/%s\n", + (gadget_is_superspeed(c->cdev->gadget) ? "super" : + (gadget_is_dualspeed(c->cdev->gadget) ? "dual" : "full")), + f->name, loop->in_ep->name, loop->out_ep->name); + return 0; +} + +static void lb_free_func(struct usb_function *f) +{ + struct f_lb_opts *opts; + + opts = container_of(f->fi, struct f_lb_opts, func_inst); + + mutex_lock(&opts->lock); + opts->refcnt--; + mutex_unlock(&opts->lock); + + usb_free_all_descriptors(f); + kfree(func_to_loop(f)); +} + +static void loopback_complete(struct usb_ep *ep, struct usb_request *req) +{ + struct f_loopback *loop = ep->driver_data; + struct usb_composite_dev *cdev = loop->function.config->cdev; + int status = req->status; + + switch (status) { + + case 0: /* normal completion? */ + if (ep == loop->out_ep) { + req->zero = (req->actual < req->length); + req->length = req->actual; + } + + /* queue the buffer for some later OUT packet */ + req->length = buflen; + status = usb_ep_queue(ep, req, GFP_ATOMIC); + if (status == 0) + return; + + /* "should never get here" */ + /* FALLTHROUGH */ + + default: + ERROR(cdev, "%s loop complete --> %d, %d/%d\n", ep->name, + status, req->actual, req->length); + /* FALLTHROUGH */ + + /* NOTE: since this driver doesn't maintain an explicit record + * of requests it submitted (just maintains qlen count), we + * rely on the hardware driver to clean up on disconnect or + * endpoint disable. + */ + case -ECONNABORTED: /* hardware forced ep reset */ + case -ECONNRESET: /* request dequeued */ + case -ESHUTDOWN: /* disconnect from host */ + free_ep_req(ep, req); + return; + } +} + +static void disable_loopback(struct f_loopback *loop) +{ + struct usb_composite_dev *cdev; + + cdev = loop->function.config->cdev; + disable_endpoints(cdev, loop->in_ep, loop->out_ep, NULL, NULL); + VDBG(cdev, "%s disabled\n", loop->function.name); +} + +static inline struct usb_request *lb_alloc_ep_req(struct usb_ep *ep, int len) +{ + return alloc_ep_req(ep, len, buflen); +} + +static int enable_endpoint(struct usb_composite_dev *cdev, struct f_loopback *loop, + struct usb_ep *ep) +{ + struct usb_request *req; + unsigned i; + int result; + + /* + * one endpoint writes data back IN to the host while another endpoint + * just reads OUT packets + */ + result = config_ep_by_speed(cdev->gadget, &(loop->function), ep); + if (result) + goto fail0; + result = usb_ep_enable(ep); + if (result < 0) + goto fail0; + ep->driver_data = loop; + + /* + * allocate a bunch of read buffers and queue them all at once. + * we buffer at most 'qlen' transfers; fewer if any need more + * than 'buflen' bytes each. + */ + for (i = 0; i < qlen && result == 0; i++) { + req = lb_alloc_ep_req(ep, 0); + if (!req) + goto fail1; + + req->complete = loopback_complete; + result = usb_ep_queue(ep, req, GFP_ATOMIC); + if (result) { + ERROR(cdev, "%s queue req --> %d\n", + ep->name, result); + goto fail1; + } + } + + return 0; + +fail1: + usb_ep_disable(ep); + +fail0: + return result; +} + +static int +enable_loopback(struct usb_composite_dev *cdev, struct f_loopback *loop) +{ + int result = 0; + + result = enable_endpoint(cdev, loop, loop->in_ep); + if (result) + return result; + + result = enable_endpoint(cdev, loop, loop->out_ep); + if (result) + return result; + + DBG(cdev, "%s enabled\n", loop->function.name); + return result; +} + +static int loopback_set_alt(struct usb_function *f, + unsigned intf, unsigned alt) +{ + struct f_loopback *loop = func_to_loop(f); + struct usb_composite_dev *cdev = f->config->cdev; + + /* we know alt is zero */ + if (loop->in_ep->driver_data) + disable_loopback(loop); + return enable_loopback(cdev, loop); +} + +static void loopback_disable(struct usb_function *f) +{ + struct f_loopback *loop = func_to_loop(f); + + disable_loopback(loop); +} + +static struct usb_function *loopback_alloc(struct usb_function_instance *fi) +{ + struct f_loopback *loop; + struct f_lb_opts *lb_opts; + + loop = kzalloc(sizeof *loop, GFP_KERNEL); + if (!loop) + return ERR_PTR(-ENOMEM); + + lb_opts = container_of(fi, struct f_lb_opts, func_inst); + + mutex_lock(&lb_opts->lock); + lb_opts->refcnt++; + mutex_unlock(&lb_opts->lock); + + buflen = lb_opts->bulk_buflen; + qlen = lb_opts->qlen; + if (!qlen) + qlen = 32; + + loop->function.name = "loopback"; + loop->function.bind = loopback_bind; + loop->function.set_alt = loopback_set_alt; + loop->function.disable = loopback_disable; + loop->function.strings = loopback_strings; + + loop->function.free_func = lb_free_func; + + return &loop->function; +} + +static inline struct f_lb_opts *to_f_lb_opts(struct config_item *item) +{ + return container_of(to_config_group(item), struct f_lb_opts, + func_inst.group); +} + +CONFIGFS_ATTR_STRUCT(f_lb_opts); +CONFIGFS_ATTR_OPS(f_lb_opts); + +static void lb_attr_release(struct config_item *item) +{ + struct f_lb_opts *lb_opts = to_f_lb_opts(item); + + usb_put_function_instance(&lb_opts->func_inst); +} + +static struct configfs_item_operations lb_item_ops = { + .release = lb_attr_release, + .show_attribute = f_lb_opts_attr_show, + .store_attribute = f_lb_opts_attr_store, +}; + +static ssize_t f_lb_opts_qlen_show(struct f_lb_opts *opts, char *page) +{ + int result; + + mutex_lock(&opts->lock); + result = sprintf(page, "%d", opts->qlen); + mutex_unlock(&opts->lock); + + return result; +} + +static ssize_t f_lb_opts_qlen_store(struct f_lb_opts *opts, + const char *page, size_t len) +{ + int ret; + u32 num; + + mutex_lock(&opts->lock); + if (opts->refcnt) { + ret = -EBUSY; + goto end; + } + + ret = kstrtou32(page, 0, &num); + if (ret) + goto end; + + opts->qlen = num; + ret = len; +end: + mutex_unlock(&opts->lock); + return ret; +} + +static struct f_lb_opts_attribute f_lb_opts_qlen = + __CONFIGFS_ATTR(qlen, S_IRUGO | S_IWUSR, + f_lb_opts_qlen_show, + f_lb_opts_qlen_store); + +static ssize_t f_lb_opts_bulk_buflen_show(struct f_lb_opts *opts, char *page) +{ + int result; + + mutex_lock(&opts->lock); + result = sprintf(page, "%d", opts->bulk_buflen); + mutex_unlock(&opts->lock); + + return result; +} + +static ssize_t f_lb_opts_bulk_buflen_store(struct f_lb_opts *opts, + const char *page, size_t len) +{ + int ret; + u32 num; + + mutex_lock(&opts->lock); + if (opts->refcnt) { + ret = -EBUSY; + goto end; + } + + ret = kstrtou32(page, 0, &num); + if (ret) + goto end; + + opts->bulk_buflen = num; + ret = len; +end: + mutex_unlock(&opts->lock); + return ret; +} + +static struct f_lb_opts_attribute f_lb_opts_bulk_buflen = + __CONFIGFS_ATTR(buflen, S_IRUGO | S_IWUSR, + f_lb_opts_bulk_buflen_show, + f_lb_opts_bulk_buflen_store); + +static struct configfs_attribute *lb_attrs[] = { + &f_lb_opts_qlen.attr, + &f_lb_opts_bulk_buflen.attr, + NULL, +}; + +static struct config_item_type lb_func_type = { + .ct_item_ops = &lb_item_ops, + .ct_attrs = lb_attrs, + .ct_owner = THIS_MODULE, +}; + +static void lb_free_instance(struct usb_function_instance *fi) +{ + struct f_lb_opts *lb_opts; + + lb_opts = container_of(fi, struct f_lb_opts, func_inst); + kfree(lb_opts); +} + +static struct usb_function_instance *loopback_alloc_instance(void) +{ + struct f_lb_opts *lb_opts; + + lb_opts = kzalloc(sizeof(*lb_opts), GFP_KERNEL); + if (!lb_opts) + return ERR_PTR(-ENOMEM); + mutex_init(&lb_opts->lock); + lb_opts->func_inst.free_func_inst = lb_free_instance; + lb_opts->bulk_buflen = GZERO_BULK_BUFLEN; + lb_opts->qlen = GZERO_QLEN; + + config_group_init_type_name(&lb_opts->func_inst.group, "", + &lb_func_type); + + return &lb_opts->func_inst; +} +DECLARE_USB_FUNCTION(Loopback, loopback_alloc_instance, loopback_alloc); + +int __init lb_modinit(void) +{ + int ret; + + ret = usb_function_register(&Loopbackusb_func); + if (ret) + return ret; + return ret; +} +void __exit lb_modexit(void) +{ + usb_function_unregister(&Loopbackusb_func); +} + +MODULE_LICENSE("GPL"); -- cgit v1.2.3-54-g00ecf