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Release 4.7 drivers/usb/gadget/function/f_loopback.c

/*
 * 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 <linux/slab.h>
#include <linux/kernel.h>
#include <linux/device.h>
#include <linux/module.h>
#include <linux/err.h>
#include <linux/usb/composite.h>

#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.
 */

struct f_loopback {
	
struct usb_function	function;

	
struct usb_ep		*in_ep;
	
struct usb_ep		*out_ep;

	
unsigned                qlen;
	
unsigned                buflen;
};


static inline struct f_loopback *func_to_loop(struct usb_function *f) { return container_of(f, struct f_loopback, function); }

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david brownelldavid brownell25100.00%1100.00%
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/*-------------------------------------------------------------------------*/ 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->out_ep = usb_ep_autoconfig(cdev->gadget, &fs_loop_sink_desc); if (!loop->out_ep) goto autoconf_fail; /* 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, NULL); 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; }

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david brownelldavid brownell19068.35%233.33%
sebastian andrzej siewiorsebastian andrzej siewior5118.35%233.33%
amit blayamit blay3512.59%116.67%
john younjohn youn20.72%116.67%
Total278100.00%6100.00%


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)); }

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andrzej pietrasiewiczandrzej pietrasiewicz4062.50%125.00%
david brownelldavid brownell1828.12%125.00%
sebastian andrzej siewiorsebastian andrzej siewior69.38%250.00%
Total64100.00%4100.00%


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) { /* * We received some data from the host so let's * queue it so host can read the from our in ep */ struct usb_request *in_req = req->context; in_req->zero = (req->actual < req->length); in_req->length = req->actual; ep = loop->in_ep; req = in_req; } else { /* * We have just looped back a bunch of data * to host. Now let's wait for some more data. */ req = req->context; ep = loop->out_ep; } /* queue the buffer back to host or for next bunch of data */ status = usb_ep_queue(ep, req, GFP_ATOMIC); if (status == 0) { return; } else { ERROR(cdev, "Unable to loop back buffer to %s: %d\n", ep->name, status); goto free_req; } /* "should never get here" */ 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_req: usb_ep_free_request(ep == loop->in_ep ? loop->out_ep : loop->in_ep, req->context); free_ep_req(ep, req); return; } }

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david brownelldavid brownell15566.24%125.00%
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felipe balbifelipe balbi10.43%125.00%
Total234100.00%4100.00%


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); }

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david brownelldavid brownell5292.86%150.00%
paul zimmermanpaul zimmerman47.14%150.00%
Total56100.00%2100.00%


static inline struct usb_request *lb_alloc_ep_req(struct usb_ep *ep, int len) { struct f_loopback *loop = ep->driver_data; return alloc_ep_req(ep, len, loop->buflen); }

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andrzej pietrasiewiczandrzej pietrasiewicz2771.05%150.00%
krzysztof opasiakkrzysztof opasiak1128.95%150.00%
Total38100.00%2100.00%


static int alloc_requests(struct usb_composite_dev *cdev, struct f_loopback *loop) { struct usb_request *in_req, *out_req; int i; int result = 0; /* * allocate a bunch of read buffers and queue them all at once. * we buffer at most 'qlen' transfers; We allocate buffers only * for out transfer and reuse them in IN transfers to implement * our loopback functionality */ for (i = 0; i < loop->qlen && result == 0; i++) { result = -ENOMEM; in_req = usb_ep_alloc_request(loop->in_ep, GFP_ATOMIC); if (!in_req) goto fail; out_req = lb_alloc_ep_req(loop->out_ep, 0); if (!out_req) goto fail_in; in_req->complete = loopback_complete; out_req->complete = loopback_complete; in_req->buf = out_req->buf; /* length will be set in complete routine */ in_req->context = out_req; out_req->context = in_req; result = usb_ep_queue(loop->out_ep, out_req, GFP_ATOMIC); if (result) { ERROR(cdev, "%s queue req --> %d\n", loop->out_ep->name, result); goto fail_out; } } return 0; fail_out: free_ep_req(loop->out_ep, out_req); fail_in: usb_ep_free_request(loop->in_ep, in_req); fail: return result; }

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krzysztof opasiakkrzysztof opasiak10251.78%228.57%
david brownelldavid brownell7739.09%114.29%
felipe balbifelipe balbi147.11%114.29%
paul zimmermanpaul zimmerman21.02%114.29%
andrzej pietrasiewiczandrzej pietrasiewicz10.51%114.29%
peter chenpeter chen10.51%114.29%
Total197100.00%7100.00%


static int enable_endpoint(struct usb_composite_dev *cdev, struct f_loopback *loop, struct usb_ep *ep) { int result; result = config_ep_by_speed(cdev->gadget, &(loop->function), ep); if (result) goto out; result = usb_ep_enable(ep); if (result < 0) goto out; ep->driver_data = loop; result = 0; out: return result; }

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krzysztof opasiakkrzysztof opasiak7290.00%133.33%
felipe balbifelipe balbi56.25%133.33%
david brownelldavid brownell33.75%133.33%
Total80100.00%3100.00%


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) goto out; result = enable_endpoint(cdev, loop, loop->out_ep); if (result) goto disable_in; result = alloc_requests(cdev, loop); if (result) goto disable_out; DBG(cdev, "%s enabled\n", loop->function.name); return 0; disable_out: usb_ep_disable(loop->out_ep); disable_in: usb_ep_disable(loop->in_ep); out: return result; }

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felipe balbifelipe balbi5043.10%133.33%
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david brownelldavid brownell2218.97%133.33%
Total116100.00%3100.00%


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 */ disable_loopback(loop); return enable_loopback(cdev, loop); }

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static void loopback_disable(struct usb_function *f) { struct f_loopback *loop = func_to_loop(f); disable_loopback(loop); }

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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); loop->buflen = lb_opts->bulk_buflen; loop->qlen = lb_opts->qlen; if (!loop->qlen) loop->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; }

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david brownelldavid brownell7143.83%125.00%
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andrzej pietrasiewiczandrzej pietrasiewicz2112.96%125.00%
krzysztof opasiakkrzysztof opasiak84.94%125.00%
Total162100.00%4100.00%


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); }

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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); }

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static struct configfs_item_operations lb_item_ops = { .release = lb_attr_release, };
static ssize_t f_lb_opts_qlen_show(struct config_item *item, char *page) { struct f_lb_opts *opts = to_f_lb_opts(item); int result; mutex_lock(&opts->lock); result = sprintf(page, "%d\n", opts->qlen); mutex_unlock(&opts->lock); return result; }

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andrzej pietrasiewiczandrzej pietrasiewicz4778.33%133.33%
christoph hellwigchristoph hellwig1220.00%133.33%
krzysztof opasiakkrzysztof opasiak11.67%133.33%
Total60100.00%3100.00%


static ssize_t f_lb_opts_qlen_store(struct config_item *item, const char *page, size_t len) { struct f_lb_opts *opts = to_f_lb_opts(item); 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; }

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andrzej pietrasiewiczandrzej pietrasiewicz8988.12%150.00%
christoph hellwigchristoph hellwig1211.88%150.00%
Total101100.00%2100.00%

CONFIGFS_ATTR(f_lb_opts_, qlen);
static ssize_t f_lb_opts_bulk_buflen_show(struct config_item *item, char *page) { struct f_lb_opts *opts = to_f_lb_opts(item); int result; mutex_lock(&opts->lock); result = sprintf(page, "%d\n", opts->bulk_buflen); mutex_unlock(&opts->lock); return result; }

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andrzej pietrasiewiczandrzej pietrasiewicz4778.33%133.33%
christoph hellwigchristoph hellwig1220.00%133.33%
krzysztof opasiakkrzysztof opasiak11.67%133.33%
Total60100.00%3100.00%


static ssize_t f_lb_opts_bulk_buflen_store(struct config_item *item, const char *page, size_t len) { struct f_lb_opts *opts = to_f_lb_opts(item); 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; }

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Total101100.00%2100.00%

CONFIGFS_ATTR(f_lb_opts_, bulk_buflen); static struct configfs_attribute *lb_attrs[] = { &f_lb_opts_attr_qlen, &f_lb_opts_attr_bulk_buflen, 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); }

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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; }

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sebastian andrzej siewiorsebastian andrzej siewior4550.56%133.33%
andrzej pietrasiewiczandrzej pietrasiewicz3539.33%133.33%
david brownelldavid brownell910.11%133.33%
Total89100.00%3100.00%

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; }

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Total29100.00%2100.00%


void __exit lb_modexit(void) { usb_function_unregister(&Loopbackusb_func); }

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MODULE_LICENSE("GPL");

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david brownelldavid brownell100040.75%29.52%
andrzej pietrasiewiczandrzej pietrasiewicz51420.95%29.52%
krzysztof opasiakkrzysztof opasiak32613.28%419.05%
sebastian andrzej siewiorsebastian andrzej siewior26010.59%314.29%
amit blayamit blay2098.52%14.76%
felipe balbifelipe balbi702.85%14.76%
christoph hellwigchristoph hellwig582.36%14.76%
paul zimmermanpaul zimmerman60.24%14.76%
tejun heotejun heo30.12%14.76%
jingoo hanjingoo han20.08%14.76%
harvey harrisonharvey harrison20.08%14.76%
john younjohn youn20.08%14.76%
peter chenpeter chen10.04%14.76%
klaus schwarzkopfklaus schwarzkopf10.04%14.76%
Total2454100.00%21100.00%
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