From patchwork Fri Apr 29 11:41:13 2022 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Jose Ignacio Tornos Martinez X-Patchwork-Id: 567577 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id AE52BC433F5 for ; Fri, 29 Apr 2022 11:41:29 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1358586AbiD2Lop (ORCPT ); Fri, 29 Apr 2022 07:44:45 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:59526 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S233241AbiD2Lon (ORCPT ); Fri, 29 Apr 2022 07:44:43 -0400 Received: from us-smtp-delivery-124.mimecast.com (us-smtp-delivery-124.mimecast.com [170.10.133.124]) by lindbergh.monkeyblade.net (Postfix) with ESMTP id E8221252AB for ; Fri, 29 Apr 2022 04:41:23 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=redhat.com; s=mimecast20190719; t=1651232483; h=from:from:reply-to:subject:subject:date:date:message-id:message-id: to:to:cc:cc:mime-version:mime-version: content-transfer-encoding:content-transfer-encoding; bh=dTDdSIiixWPV+JPy4nNDKS4YnArMT0+pldgLQzhjmJw=; b=DijlqYvwhuUGQCof/g0nNm0LF5KGgDkiGh4mu6E43ThMXtWMVFa17x8++BmQtrPQ7nteFm xpJf3o00Nb6IFucfZ9QKIEbi9Gs7LCAUXBQ9l7ppnmPpeVy6tARqOVwBvqGLWrWws5CZ/R 1JfDtuPm2/kwK4HrwA4CVVmiMmVNGUU= Received: from mimecast-mx02.redhat.com (mimecast-mx02.redhat.com [66.187.233.88]) by relay.mimecast.com with ESMTP with STARTTLS (version=TLSv1.2, cipher=TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384) id us-mta-592-0iCvrH-FPbGdH9x0BS84Iw-1; Fri, 29 Apr 2022 07:41:18 -0400 X-MC-Unique: 0iCvrH-FPbGdH9x0BS84Iw-1 Received: from smtp.corp.redhat.com (int-mx02.intmail.prod.int.rdu2.redhat.com [10.11.54.2]) (using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits)) (No client certificate requested) by mimecast-mx02.redhat.com (Postfix) with ESMTPS id 60FB91014A64; Fri, 29 Apr 2022 11:41:18 +0000 (UTC) Received: from fedora.redhat.com (unknown [10.39.192.165]) by smtp.corp.redhat.com (Postfix) with ESMTP id 0104F40C1244; Fri, 29 Apr 2022 11:41:16 +0000 (UTC) From: Jose Ignacio Tornos Martinez To: marcel@holtmann.org, johan.hedberg@gmail.com, luiz.dentz@gmail.com, linux-bluetooth@vger.kernel.org Cc: Jose Ignacio Tornos Martinez Subject: [PATCH] btusb: CSR chip hangs when unbound Date: Fri, 29 Apr 2022 13:41:13 +0200 Message-Id: <20220429114113.356263-1-jtornosm@redhat.com> MIME-Version: 1.0 X-Scanned-By: MIMEDefang 2.84 on 10.11.54.2 Precedence: bulk List-ID: X-Mailing-List: linux-bluetooth@vger.kernel.org Bluetooth Dongles with CSR chip (i.e. USB Bluetooth V4.0 Dongle by Trust) hang when they are unbound from 'unbind' sysfs entry and can not be bound again. The reason is CSR chip hangs when usb configuration command with index 0 (used to unconfigure) is sent during disconnection. To avoid this unwanted result, it is necessary not to send this command for CSR chip when usb device is unbound. Besides, "skip_unconfigure" sysfs entry has been created for testing purposes with these or other devices. Athough device is not unconfigured, it is better to avoid device hanging to be able to operate. Even bluetooth can be previously turned off. On the other hand, this is not important if usb device is going to be bound again (normal behavior), i.e. with usbip. Signed-off-by: Jose Ignacio Tornos Martinez --- drivers/bluetooth/btusb.c | 6 ++++++ drivers/usb/core/generic.c | 2 +- drivers/usb/core/sysfs.c | 36 ++++++++++++++++++++++++++++++++++++ include/linux/usb.h | 2 ++ 4 files changed, 45 insertions(+), 1 deletion(-) diff --git a/drivers/bluetooth/btusb.c b/drivers/bluetooth/btusb.c index b7c72eb96c87..7eb951e47dc2 100644 --- a/drivers/bluetooth/btusb.c +++ b/drivers/bluetooth/btusb.c @@ -4836,7 +4836,13 @@ static int btusb_probe(struct usb_interface *intf, /* Fake CSR devices with broken commands */ if (le16_to_cpu(udev->descriptor.idVendor) == 0x0a12 && le16_to_cpu(udev->descriptor.idProduct) == 0x0001) + { hdev->setup = btusb_setup_csr; + /* This device hangs when configuration command with + * index 0 (unconfigure) is sent, avoid this at least + * if it is unbound */ + udev->skip_unconfigure = 1; + } } if (id->driver_info & BTUSB_SNIFFER) { diff --git a/drivers/usb/core/generic.c b/drivers/usb/core/generic.c index 26f9fb9f67ca..f25171284119 100644 --- a/drivers/usb/core/generic.c +++ b/drivers/usb/core/generic.c @@ -256,7 +256,7 @@ void usb_generic_driver_disconnect(struct usb_device *udev) /* if this is only an unbind, not a physical disconnect, then * unconfigure the device */ - if (udev->actconfig) + if (!udev->skip_unconfigure && udev->actconfig) usb_set_configuration(udev, -1); } diff --git a/drivers/usb/core/sysfs.c b/drivers/usb/core/sysfs.c index fa2e49d432ff..7cecc558e2c4 100644 --- a/drivers/usb/core/sysfs.c +++ b/drivers/usb/core/sysfs.c @@ -1189,6 +1189,41 @@ static struct device_attribute dev_attr_interface_authorized = __ATTR(authorized, S_IRUGO | S_IWUSR, interface_authorized_show, interface_authorized_store); +static ssize_t skip_unconfigure_show(struct device *dev, + struct device_attribute *attr, char *buf) +{ + struct usb_interface *intf = to_usb_interface(dev); + struct usb_device *udev = interface_to_usbdev(intf); + int val; + + if (usb_lock_device_interruptible(udev) < 0) + return -EINTR; + val = udev->skip_unconfigure; + usb_unlock_device(udev); + + return sprintf(buf, "%d\n", val); +} + +static ssize_t skip_unconfigure_store(struct device *dev, + struct device_attribute *attr, + const char *buf, size_t count) +{ + struct usb_interface *intf = to_usb_interface(dev); + struct usb_device *udev = interface_to_usbdev(intf); + int val; + + if (sscanf(buf, "%d", &val) != 1 || val < 0 || val > 1) + return -EINVAL; + + if (usb_lock_device_interruptible(udev) < 0) + return -EINTR; + udev->skip_unconfigure = val; + usb_unlock_device(udev); + + return count; +} +static DEVICE_ATTR_RW(skip_unconfigure); + static struct attribute *intf_attrs[] = { &dev_attr_bInterfaceNumber.attr, &dev_attr_bAlternateSetting.attr, @@ -1199,6 +1234,7 @@ static struct attribute *intf_attrs[] = { &dev_attr_modalias.attr, &dev_attr_supports_autosuspend.attr, &dev_attr_interface_authorized.attr, + &dev_attr_skip_unconfigure.attr, NULL, }; static const struct attribute_group intf_attr_grp = { diff --git a/include/linux/usb.h b/include/linux/usb.h index 86a73d834e38..55828cd0a0d1 100644 --- a/include/linux/usb.h +++ b/include/linux/usb.h @@ -618,6 +618,7 @@ struct usb3_lpm_parameters { * parent->hub_delay + wHubDelay + tTPTransmissionDelay (40ns) * Will be used as wValue for SetIsochDelay requests. * @use_generic_driver: ask driver core to reprobe using the generic driver. + * @skip_unconfigure: disable unconfigure operation for devices without support. * * Notes: * Usbcore drivers should not set usbdev->state directly. Instead use @@ -704,6 +705,7 @@ struct usb_device { u16 hub_delay; unsigned use_generic_driver:1; + unsigned skip_unconfigure:1; }; #define to_usb_device(d) container_of(d, struct usb_device, dev)