/* $NetBSD: usbdi_util.c,v 1.70.4.2 2020/04/13 08:04:51 martin Exp $ */ /* * Copyright (c) 1998, 2012 The NetBSD Foundation, Inc. * All rights reserved. * * This code is derived from software contributed to The NetBSD Foundation * by Lennart Augustsson (lennart@augustsson.net) at * Carlstedt Research & Technology and Matthew R. Green (mrg@eterna.com.au). * * Redistribution and use in source and binary forms, with or without * modification, are permitted provided that the following conditions * are met: * 1. Redistributions of source code must retain the above copyright * notice, this list of conditions and the following disclaimer. * 2. Redistributions in binary form must reproduce the above copyright * notice, this list of conditions and the following disclaimer in the * documentation and/or other materials provided with the distribution. * * THIS SOFTWARE IS PROVIDED BY THE NETBSD FOUNDATION, INC. AND CONTRIBUTORS * ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED * TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR * PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE FOUNDATION OR CONTRIBUTORS * BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE * POSSIBILITY OF SUCH DAMAGE. */ #include __KERNEL_RCSID(0, "$NetBSD: usbdi_util.c,v 1.70.4.2 2020/04/13 08:04:51 martin Exp $"); #ifdef _KERNEL_OPT #include "opt_usb.h" #endif #include #include #include #include #include #include #include #include #include #include #include #include #include #include #define DPRINTF(FMT,A,B,C,D) USBHIST_LOGN(usbdebug,1,FMT,A,B,C,D) #define DPRINTFN(N,FMT,A,B,C,D) USBHIST_LOGN(usbdebug,N,FMT,A,B,C,D) usbd_status usbd_get_desc(struct usbd_device *dev, int type, int index, int len, void *desc) { usb_device_request_t req; usbd_status err; USBHIST_FUNC(); USBHIST_CALLARGS(usbdebug, "type=%jd, index=%jd, len=%jd", type, index, len, 0); /* * Provide hard-coded configuration descriptors * for devices that may corrupt it. This cannot * be done for device descriptors which are used * to identify the device. */ if (type != UDESC_DEVICE && dev->ud_quirks->uq_flags & UQ_DESC_CORRUPT) { err = usbd_get_desc_fake(dev, type, index, len, desc); goto out; } req.bmRequestType = UT_READ_DEVICE; req.bRequest = UR_GET_DESCRIPTOR; USETW2(req.wValue, type, index); USETW(req.wIndex, 0); USETW(req.wLength, len); err = usbd_do_request(dev, &req, desc); out: return err; } usbd_status usbd_get_config_desc(struct usbd_device *dev, int confidx, usb_config_descriptor_t *d) { USBHIST_FUNC(); USBHIST_CALLARGS(usbdebug, "confidx=%jd", confidx, 0, 0, 0); usbd_status err; err = usbd_get_desc(dev, UDESC_CONFIG, confidx, USB_CONFIG_DESCRIPTOR_SIZE, d); if (err) return err; if (d->bDescriptorType != UDESC_CONFIG) { DPRINTFN(1, "confidx=%jd, bad desc len=%jd type=%jd", confidx, d->bLength, d->bDescriptorType, 0); return USBD_INVAL; } return USBD_NORMAL_COMPLETION; } usbd_status usbd_get_config_desc_full(struct usbd_device *dev, int conf, void *d, int size) { USBHIST_FUNC(); USBHIST_CALLARGS(usbdebug, "conf=%jd", conf, 0, 0, 0); return usbd_get_desc(dev, UDESC_CONFIG, conf, size, d); } usbd_status usbd_get_bos_desc(struct usbd_device *dev, int confidx, usb_bos_descriptor_t *d) { USBHIST_FUNC(); USBHIST_CALLARGS(usbdebug, "confidx=%jd", confidx, 0, 0, 0); usbd_status err; err = usbd_get_desc(dev, UDESC_BOS, confidx, USB_BOS_DESCRIPTOR_SIZE, d); if (err) return err; if (d->bDescriptorType != UDESC_BOS) { DPRINTFN(1, "confidx=%jd, bad desc len=%jd type=%jd", confidx, d->bLength, d->bDescriptorType, 0); return USBD_INVAL; } return USBD_NORMAL_COMPLETION; } usbd_status usbd_get_bos_desc_full(struct usbd_device *dev, int conf, void *d, int size) { USBHIST_FUNC(); USBHIST_CALLARGS(usbdebug, "conf=%jd", conf, 0, 0, 0); return usbd_get_desc(dev, UDESC_BOS, conf, size, d); } usbd_status usbd_get_device_desc(struct usbd_device *dev, usb_device_descriptor_t *d) { USBHIST_FUNC(); USBHIST_CALLED(usbdebug); return usbd_get_desc(dev, UDESC_DEVICE, 0, USB_DEVICE_DESCRIPTOR_SIZE, d); } /* * Get the first 8 bytes of the device descriptor. * Do as Windows does: try to read 64 bytes -- there are devices which * recognize the initial descriptor fetch (before the control endpoint's * MaxPacketSize is known by the host) by exactly this length. */ usbd_status usbd_get_initial_ddesc(struct usbd_device *dev, usb_device_descriptor_t *desc) { USBHIST_FUNC(); USBHIST_CALLARGS(usbdebug, "dev %#jx", (uintptr_t)dev, 0, 0, 0); usb_device_request_t req; char buf[64]; int res, actlen; req.bmRequestType = UT_READ_DEVICE; req.bRequest = UR_GET_DESCRIPTOR; USETW2(req.wValue, UDESC_DEVICE, 0); USETW(req.wIndex, 0); USETW(req.wLength, 8); res = usbd_do_request_flags(dev, &req, buf, USBD_SHORT_XFER_OK, &actlen, USBD_DEFAULT_TIMEOUT); if (res) return res; if (actlen < 8) return USBD_SHORT_XFER; memcpy(desc, buf, 8); return USBD_NORMAL_COMPLETION; } usbd_status usbd_get_string_desc(struct usbd_device *dev, int sindex, int langid, usb_string_descriptor_t *sdesc, int *sizep) { USBHIST_FUNC(); USBHIST_CALLED(usbdebug); usb_device_request_t req; usbd_status err; int actlen; /* * Pass a full-sized buffer to usbd_do_request_len(). At least * one device has been seen returning additional data beyond the * provided buffers (2-bytes written shortly after the request * claims to have completed and returned the 2 byte header, * corrupting other memory.) */ req.bmRequestType = UT_READ_DEVICE; req.bRequest = UR_GET_DESCRIPTOR; USETW2(req.wValue, UDESC_STRING, sindex); USETW(req.wIndex, langid); USETW(req.wLength, 2); /* only size byte first */ err = usbd_do_request_len(dev, &req, sizeof(*sdesc), sdesc, USBD_SHORT_XFER_OK, &actlen, USBD_DEFAULT_TIMEOUT); if (err) return err; if (actlen < 2) return USBD_SHORT_XFER; if (sdesc->bLength > sizeof(*sdesc)) return USBD_INVAL; USETW(req.wLength, sdesc->bLength); /* the whole string */ err = usbd_do_request_len(dev, &req, sizeof(*sdesc), sdesc, USBD_SHORT_XFER_OK, &actlen, USBD_DEFAULT_TIMEOUT); if (err) return err; if (actlen != sdesc->bLength) { DPRINTF("expected %jd, got %jd", sdesc->bLength, actlen, 0, 0); } *sizep = actlen; return USBD_NORMAL_COMPLETION; } /* -------------------------------------------------------------------------- */ usbd_status usbd_get_device_status(struct usbd_device *dev, usb_status_t *st) { USBHIST_FUNC(); USBHIST_CALLED(usbdebug); usb_device_request_t req; req.bmRequestType = UT_READ_DEVICE; req.bRequest = UR_GET_STATUS; USETW(req.wValue, 0); USETW(req.wIndex, 0); USETW(req.wLength, sizeof(usb_status_t)); return usbd_do_request(dev, &req, st); } usbd_status usbd_get_hub_status(struct usbd_device *dev, usb_hub_status_t *st) { USBHIST_FUNC(); USBHIST_CALLARGS(usbdebug, "dev %#jx", (uintptr_t)dev, 0, 0, 0); usb_device_request_t req; req.bmRequestType = UT_READ_CLASS_DEVICE; req.bRequest = UR_GET_STATUS; USETW(req.wValue, 0); USETW(req.wIndex, 0); USETW(req.wLength, sizeof(usb_hub_status_t)); return usbd_do_request(dev, &req, st); } usbd_status usbd_get_port_status(struct usbd_device *dev, int port, usb_port_status_t *ps) { USBHIST_FUNC(); USBHIST_CALLARGS(usbdebug, "dev %#jx port %jd", (uintptr_t)dev, port, 0, 0); usb_device_request_t req; req.bmRequestType = UT_READ_CLASS_OTHER; req.bRequest = UR_GET_STATUS; USETW(req.wValue, 0); USETW(req.wIndex, port); USETW(req.wLength, sizeof(*ps)); return usbd_do_request(dev, &req, ps); } /* USB 3.1 10.16.2.6, 10.16.2.6.3 */ usbd_status usbd_get_port_status_ext(struct usbd_device *dev, int port, usb_port_status_ext_t *pse) { USBHIST_FUNC(); USBHIST_CALLARGS(usbdebug, "dev %#jx port %jd", (uintptr_t)dev, port, 0, 0); usb_device_request_t req; req.bmRequestType = UT_READ_CLASS_OTHER; req.bRequest = UR_GET_STATUS; USETW2(req.wValue, 0, UR_PST_EXT_PORT_STATUS); USETW(req.wIndex, port); USETW(req.wLength, sizeof(*pse)); return usbd_do_request(dev, &req, pse); } /* -------------------------------------------------------------------------- */ usbd_status usbd_clear_hub_feature(struct usbd_device *dev, int sel) { USBHIST_FUNC(); USBHIST_CALLARGS(usbdebug, "dev %#jx sel %jd", (uintptr_t)dev, sel, 0, 0); usb_device_request_t req; req.bmRequestType = UT_WRITE_CLASS_DEVICE; req.bRequest = UR_CLEAR_FEATURE; USETW(req.wValue, sel); USETW(req.wIndex, 0); USETW(req.wLength, 0); return usbd_do_request(dev, &req, 0); } usbd_status usbd_set_hub_feature(struct usbd_device *dev, int sel) { USBHIST_FUNC(); USBHIST_CALLARGS(usbdebug, "dev %#jx sel %jd", (uintptr_t)dev, sel, 0, 0); usb_device_request_t req; req.bmRequestType = UT_WRITE_CLASS_DEVICE; req.bRequest = UR_SET_FEATURE; USETW(req.wValue, sel); USETW(req.wIndex, 0); USETW(req.wLength, 0); return usbd_do_request(dev, &req, 0); } usbd_status usbd_clear_port_feature(struct usbd_device *dev, int port, int sel) { USBHIST_FUNC(); USBHIST_CALLARGS(usbdebug, "dev %#jx port %jd sel %jd", (uintptr_t)dev, port, sel, 0); usb_device_request_t req; req.bmRequestType = UT_WRITE_CLASS_OTHER; req.bRequest = UR_CLEAR_FEATURE; USETW(req.wValue, sel); USETW(req.wIndex, port); USETW(req.wLength, 0); return usbd_do_request(dev, &req, 0); } usbd_status usbd_set_port_feature(struct usbd_device *dev, int port, int sel) { USBHIST_FUNC(); USBHIST_CALLARGS(usbdebug, "dev %#jx port %jd sel %.d", (uintptr_t)dev, sel, 0, 0); usb_device_request_t req; req.bmRequestType = UT_WRITE_CLASS_OTHER; req.bRequest = UR_SET_FEATURE; USETW(req.wValue, sel); USETW(req.wIndex, port); USETW(req.wLength, 0); return usbd_do_request(dev, &req, 0); } usbd_status usbd_set_port_u1_timeout(struct usbd_device *dev, int port, int timeout) { USBHIST_FUNC(); USBHIST_CALLARGS(usbdebug, "dev %#jx port %jd timeout %.d", (uintptr_t)dev, port, timeout, 0); usb_device_request_t req; req.bmRequestType = UT_WRITE_CLASS_OTHER; req.bRequest = UR_SET_FEATURE; USETW(req.wValue, UHF_PORT_U1_TIMEOUT); USETW2(req.wIndex, timeout, port); USETW(req.wLength, 0); return usbd_do_request(dev, &req, 0); } usbd_status usbd_set_port_u2_timeout(struct usbd_device *dev, int port, int timeout) { USBHIST_FUNC(); USBHIST_CALLARGS(usbdebug, "dev %#jx port %jd timeout %jd", (uintptr_t)dev, port, timeout, 0); usb_device_request_t req; req.bmRequestType = UT_WRITE_CLASS_OTHER; req.bRequest = UR_SET_FEATURE; USETW(req.wValue, UHF_PORT_U2_TIMEOUT); USETW2(req.wIndex, timeout, port); USETW(req.wLength, 0); return usbd_do_request(dev, &req, 0); } usbd_status usbd_clear_endpoint_feature(struct usbd_device *dev, int epaddr, int sel) { USBHIST_FUNC(); USBHIST_CALLARGS(usbdebug, "dev %#jx epaddr %jd sel %jd", (uintptr_t)dev, epaddr, sel, 0); usb_device_request_t req; req.bmRequestType = UT_WRITE_ENDPOINT; req.bRequest = UR_CLEAR_FEATURE; USETW(req.wValue, sel); USETW(req.wIndex, epaddr); USETW(req.wLength, 0); return usbd_do_request(dev, &req, 0); } /* -------------------------------------------------------------------------- */ usbd_status usbd_get_config(struct usbd_device *dev, uint8_t *conf) { USBHIST_FUNC(); USBHIST_CALLARGS(usbdebug, "dev %#jx", (uintptr_t)dev, 0, 0, 0); usb_device_request_t req; req.bmRequestType = UT_READ_DEVICE; req.bRequest = UR_GET_CONFIG; USETW(req.wValue, 0); USETW(req.wIndex, 0); USETW(req.wLength, 1); return usbd_do_request(dev, &req, conf); } usbd_status usbd_set_config(struct usbd_device *dev, int conf) { USBHIST_FUNC(); USBHIST_CALLARGS(usbdebug, "dev %#jx conf %jd", (uintptr_t)dev, conf, 0, 0); usb_device_request_t req; req.bmRequestType = UT_WRITE_DEVICE; req.bRequest = UR_SET_CONFIG; USETW(req.wValue, conf); USETW(req.wIndex, 0); USETW(req.wLength, 0); return usbd_do_request(dev, &req, 0); } usbd_status usbd_set_address(struct usbd_device *dev, int addr) { USBHIST_FUNC(); USBHIST_CALLARGS(usbdebug, "dev %#jx addr %jd", (uintptr_t)dev, addr, 0, 0); usb_device_request_t req; req.bmRequestType = UT_WRITE_DEVICE; req.bRequest = UR_SET_ADDRESS; USETW(req.wValue, addr); USETW(req.wIndex, 0); USETW(req.wLength, 0); return usbd_do_request(dev, &req, 0); } usbd_status usbd_set_idle(struct usbd_interface *iface, int duration, int id) { usb_interface_descriptor_t *ifd = usbd_get_interface_descriptor(iface); struct usbd_device *dev; usb_device_request_t req; USBHIST_FUNC(); USBHIST_CALLARGS(usbdebug, "duration %jd id %jd", duration, id, 0, 0); if (ifd == NULL) return USBD_IOERROR; usbd_interface2device_handle(iface, &dev); req.bmRequestType = UT_WRITE_CLASS_INTERFACE; req.bRequest = UR_SET_IDLE; USETW2(req.wValue, duration, id); USETW(req.wIndex, ifd->bInterfaceNumber); USETW(req.wLength, 0); return usbd_do_request(dev, &req, 0); } /* -------------------------------------------------------------------------- */ usbd_status usbd_get_protocol(struct usbd_interface *iface, uint8_t *report) { usb_interface_descriptor_t *id = usbd_get_interface_descriptor(iface); struct usbd_device *dev; usb_device_request_t req; USBHIST_FUNC(); USBHIST_CALLARGS(usbdebug, "iface=%#jx, endpt=%jd", (uintptr_t)iface, id->bInterfaceNumber, 0, 0); if (id == NULL) return USBD_IOERROR; usbd_interface2device_handle(iface, &dev); req.bmRequestType = UT_READ_CLASS_INTERFACE; req.bRequest = UR_GET_PROTOCOL; USETW(req.wValue, 0); USETW(req.wIndex, id->bInterfaceNumber); USETW(req.wLength, 1); return usbd_do_request(dev, &req, report); } usbd_status usbd_set_protocol(struct usbd_interface *iface, int report) { usb_interface_descriptor_t *id = usbd_get_interface_descriptor(iface); struct usbd_device *dev; usb_device_request_t req; USBHIST_FUNC(); USBHIST_CALLARGS(usbdebug, "iface=%#jx, report=%jd, endpt=%jd", (uintptr_t)iface, report, id->bInterfaceNumber, 0); if (id == NULL) return USBD_IOERROR; usbd_interface2device_handle(iface, &dev); req.bmRequestType = UT_WRITE_CLASS_INTERFACE; req.bRequest = UR_SET_PROTOCOL; USETW(req.wValue, report); USETW(req.wIndex, id->bInterfaceNumber); USETW(req.wLength, 0); return usbd_do_request(dev, &req, 0); } /* -------------------------------------------------------------------------- */ usbd_status usbd_set_report(struct usbd_interface *iface, int type, int id, void *data, int len) { usb_interface_descriptor_t *ifd = usbd_get_interface_descriptor(iface); struct usbd_device *dev; usb_device_request_t req; USBHIST_FUNC(); USBHIST_CALLARGS(usbdebug, "len=%jd", len, 0, 0, 0); if (ifd == NULL) return USBD_IOERROR; usbd_interface2device_handle(iface, &dev); req.bmRequestType = UT_WRITE_CLASS_INTERFACE; req.bRequest = UR_SET_REPORT; USETW2(req.wValue, type, id); USETW(req.wIndex, ifd->bInterfaceNumber); USETW(req.wLength, len); return usbd_do_request(dev, &req, data); } usbd_status usbd_get_report(struct usbd_interface *iface, int type, int id, void *data, int len) { usb_interface_descriptor_t *ifd = usbd_get_interface_descriptor(iface); struct usbd_device *dev; usb_device_request_t req; USBHIST_FUNC(); USBHIST_CALLARGS(usbdebug, "len=%jd", len, 0, 0, 0); if (ifd == NULL) return USBD_IOERROR; usbd_interface2device_handle(iface, &dev); req.bmRequestType = UT_READ_CLASS_INTERFACE; req.bRequest = UR_GET_REPORT; USETW2(req.wValue, type, id); USETW(req.wIndex, ifd->bInterfaceNumber); USETW(req.wLength, len); return usbd_do_request(dev, &req, data); } usbd_status usbd_get_report_descriptor(struct usbd_device *dev, int ifcno, int size, void *d) { USBHIST_FUNC(); USBHIST_CALLARGS(usbdebug, "dev %#jx ifcno %jd size %jd", (uintptr_t)dev, ifcno, size, 0); usb_device_request_t req; req.bmRequestType = UT_READ_INTERFACE; req.bRequest = UR_GET_DESCRIPTOR; USETW2(req.wValue, UDESC_REPORT, 0); /* report id should be 0 */ USETW(req.wIndex, ifcno); USETW(req.wLength, size); return usbd_do_request(dev, &req, d); } /* -------------------------------------------------------------------------- */ usb_hid_descriptor_t * usbd_get_hid_descriptor(struct usbd_interface *ifc) { usb_interface_descriptor_t *idesc = usbd_get_interface_descriptor(ifc); struct usbd_device *dev; usb_config_descriptor_t *cdesc; usb_hid_descriptor_t *hd; char *p, *end; if (idesc == NULL) return NULL; usbd_interface2device_handle(ifc, &dev); cdesc = usbd_get_config_descriptor(dev); p = (char *)idesc + idesc->bLength; end = (char *)cdesc + UGETW(cdesc->wTotalLength); for (; p < end; p += hd->bLength) { hd = (usb_hid_descriptor_t *)p; if (p + hd->bLength <= end && hd->bLength >= USB_HID_DESCRIPTOR_SIZE(0) && hd->bDescriptorType == UDESC_HID) return hd; if (hd->bDescriptorType == UDESC_INTERFACE) break; } return NULL; } usbd_status usbd_read_report_desc(struct usbd_interface *ifc, void **descp, int *sizep) { usb_interface_descriptor_t *id; usb_hid_descriptor_t *hid; struct usbd_device *dev; usbd_status err; usbd_interface2device_handle(ifc, &dev); id = usbd_get_interface_descriptor(ifc); if (id == NULL) return USBD_INVAL; hid = usbd_get_hid_descriptor(ifc); if (hid == NULL) return USBD_IOERROR; *sizep = UGETW(hid->descrs[0].wDescriptorLength); if (*sizep == 0) return USBD_INVAL; *descp = kmem_alloc(*sizep, KM_SLEEP); err = usbd_get_report_descriptor(dev, id->bInterfaceNumber, *sizep, *descp); if (err) { kmem_free(*descp, *sizep); *descp = NULL; return err; } return USBD_NORMAL_COMPLETION; } usbd_status usbd_bulk_transfer(struct usbd_xfer *xfer, struct usbd_pipe *pipe, uint16_t flags, uint32_t timeout, void *buf, uint32_t *size) { usbd_status err; USBHIST_FUNC(); USBHIST_CALLARGS(usbdebug, "start transfer %jd bytes", *size, 0, 0, 0); usbd_setup_xfer(xfer, 0, buf, *size, flags, timeout, NULL); err = usbd_sync_transfer_sig(xfer); usbd_get_xfer_status(xfer, NULL, NULL, size, NULL); DPRINTFN(1, "transferred %jd", *size, 0, 0, 0); if (err) { usbd_clear_endpoint_stall(pipe); } USBHIST_LOG(usbdebug, "<- done xfer %#jx err %jd", (uintptr_t)xfer, err, 0, 0); return err; } usbd_status usbd_intr_transfer(struct usbd_xfer *xfer, struct usbd_pipe *pipe, uint16_t flags, uint32_t timeout, void *buf, uint32_t *size) { usbd_status err; USBHIST_FUNC(); USBHIST_CALLARGS(usbdebug, "start transfer %jd bytes", *size, 0, 0, 0); usbd_setup_xfer(xfer, 0, buf, *size, flags, timeout, NULL); err = usbd_sync_transfer_sig(xfer); usbd_get_xfer_status(xfer, NULL, NULL, size, NULL); DPRINTFN(1, "transferred %jd", *size, 0, 0, 0); if (err) { usbd_clear_endpoint_stall(pipe); } USBHIST_LOG(usbdebug, "<- done xfer %#jx err %jd", (uintptr_t)xfer, err, 0, 0); return err; } void usb_detach_waitold(device_t dv) { USBHIST_FUNC(); USBHIST_CALLARGS(usbdebug, "waiting for dv %#jx", (uintptr_t)dv, 0, 0, 0); if (tsleep(dv, PZERO, "usbdet", hz * 60)) /* XXXSMP ok */ aprint_error_dev(dv, "usb_detach_waitold: didn't detach\n"); DPRINTFN(1, "done", 0, 0, 0, 0); } void usb_detach_wakeupold(device_t dv) { USBHIST_FUNC(); USBHIST_CALLARGS(usbdebug, "for dv %#jx", (uintptr_t)dv, 0, 0, 0); wakeup(dv); /* XXXSMP ok */ } /* -------------------------------------------------------------------------- */ void usb_desc_iter_init(struct usbd_device *dev, usbd_desc_iter_t *iter) { const usb_config_descriptor_t *cd = usbd_get_config_descriptor(dev); iter->cur = (const uByte *)cd; iter->end = (const uByte *)cd + UGETW(cd->wTotalLength); } const usb_descriptor_t * usb_desc_iter_peek(usbd_desc_iter_t *iter) { const usb_descriptor_t *desc; if (iter->cur + sizeof(usb_descriptor_t) >= iter->end) { if (iter->cur != iter->end) printf("%s: bad descriptor\n", __func__); return NULL; } desc = (const usb_descriptor_t *)iter->cur; if (desc->bLength < USB_DESCRIPTOR_SIZE) { printf("%s: descriptor length too small\n", __func__); return NULL; } if (iter->cur + desc->bLength > iter->end) { printf("%s: descriptor length too large\n", __func__); return NULL; } return desc; } const usb_descriptor_t * usb_desc_iter_next(usbd_desc_iter_t *iter) { const usb_descriptor_t *desc = usb_desc_iter_peek(iter); if (desc == NULL) return NULL; iter->cur += desc->bLength; return desc; } /* Return the next interface descriptor, skipping over any other * descriptors. Returns NULL at the end or on error. */ const usb_interface_descriptor_t * usb_desc_iter_next_interface(usbd_desc_iter_t *iter) { const usb_descriptor_t *desc; while ((desc = usb_desc_iter_peek(iter)) != NULL && desc->bDescriptorType != UDESC_INTERFACE) { usb_desc_iter_next(iter); } return (const usb_interface_descriptor_t *)usb_desc_iter_next(iter); } /* Returns the next non-interface descriptor, returning NULL when the * next descriptor would be an interface descriptor. */ const usb_descriptor_t * usb_desc_iter_next_non_interface(usbd_desc_iter_t *iter) { const usb_descriptor_t *desc; if ((desc = usb_desc_iter_peek(iter)) != NULL && desc->bDescriptorType != UDESC_INTERFACE) { return usb_desc_iter_next(iter); } else { return NULL; } } const usb_cdc_descriptor_t * usb_find_desc(struct usbd_device *dev, int type, int subtype) { usbd_desc_iter_t iter; const usb_cdc_descriptor_t *desc; usb_desc_iter_init(dev, &iter); for (;;) { desc = (const usb_cdc_descriptor_t *)usb_desc_iter_next(&iter); if (!desc || (desc->bDescriptorType == type && (subtype == USBD_CDCSUBTYPE_ANY || subtype == desc->bDescriptorSubtype))) break; } return desc; } /* same as usb_find_desc(), but searches only in the specified interface. */ const usb_cdc_descriptor_t * usb_find_desc_if(struct usbd_device *dev, int type, int subtype, usb_interface_descriptor_t *id) { usbd_desc_iter_t iter; const usb_cdc_descriptor_t *desc; if (id == NULL) return usb_find_desc(dev, type, subtype); usb_desc_iter_init(dev, &iter); iter.cur = (void *)id; /* start from the interface desc */ usb_desc_iter_next(&iter); /* and skip it */ while ((desc = (const usb_cdc_descriptor_t *)usb_desc_iter_next(&iter)) != NULL) { if (desc->bDescriptorType == UDESC_INTERFACE) { /* we ran into the next interface --- not found */ return NULL; } if (desc->bDescriptorType == type && (subtype == USBD_CDCSUBTYPE_ANY || subtype == desc->bDescriptorSubtype)) break; } return desc; }