Date: Thu, 8 Oct 2020 11:30:22 +0000 (UTC) From: Hans Petter Selasky <hselasky@FreeBSD.org> To: src-committers@freebsd.org, svn-src-all@freebsd.org, svn-src-head@freebsd.org Subject: svn commit: r366536 - head/sys/dev/usb Message-ID: <202010081130.098BUMe9006774@repo.freebsd.org>
next in thread | raw e-mail | index | archive | help
Author: hselasky Date: Thu Oct 8 11:30:22 2020 New Revision: 366536 URL: https://svnweb.freebsd.org/changeset/base/366536 Log: Try a bit harder to get the USB device descriptor in case the initial read fails. MFC after: 1 week Sponsored by: Mellanox Technologies // NVIDIA Networking Modified: head/sys/dev/usb/usb_request.c Modified: head/sys/dev/usb/usb_request.c ============================================================================== --- head/sys/dev/usb/usb_request.c Thu Oct 8 11:25:19 2020 (r366535) +++ head/sys/dev/usb/usb_request.c Thu Oct 8 11:30:22 2020 (r366536) @@ -1973,9 +1973,23 @@ usbd_setup_device_desc(struct usb_device *udev, struct /* get partial device descriptor, some devices crash on this */ err = usbd_req_get_desc(udev, mtx, NULL, &udev->ddesc, USB_MAX_IPACKET, USB_MAX_IPACKET, 0, UDESC_DEVICE, 0, 0); - if (err != 0) - break; - + if (err != 0) { + DPRINTF("Trying fallback for getting the USB device descriptor\n"); + /* try 8 bytes bMaxPacketSize */ + udev->ddesc.bMaxPacketSize = 8; + /* get full device descriptor */ + err = usbd_req_get_device_desc(udev, mtx, &udev->ddesc); + if (err == 0) + break; + /* try 16 bytes bMaxPacketSize */ + udev->ddesc.bMaxPacketSize = 16; + /* get full device descriptor */ + err = usbd_req_get_device_desc(udev, mtx, &udev->ddesc); + if (err == 0) + break; + /* try 32/64 bytes bMaxPacketSize */ + udev->ddesc.bMaxPacketSize = 32; + } /* get the full device descriptor */ err = usbd_req_get_device_desc(udev, mtx, &udev->ddesc); break;
Want to link to this message? Use this URL: <https://mail-archive.FreeBSD.org/cgi/mid.cgi?202010081130.098BUMe9006774>