From patchwork Tue Jun 30 05:44:07 2020 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: "Zhang, Qiang" X-Patchwork-Id: 11635575 Return-Path: Received: from mail.kernel.org (pdx-korg-mail-1.web.codeaurora.org [172.30.200.123]) by pdx-korg-patchwork-2.web.codeaurora.org (Postfix) with ESMTP id 1CEEF92A for ; Wed, 1 Jul 2020 07:31:05 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 0D5FE206C3 for ; Wed, 1 Jul 2020 07:31:05 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1728238AbgGAHbD (ORCPT ); Wed, 1 Jul 2020 03:31:03 -0400 Received: from mail1.windriver.com ([147.11.146.13]:45764 "EHLO mail1.windriver.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1727981AbgGAHbC (ORCPT ); Wed, 1 Jul 2020 03:31:02 -0400 Received: from ALA-HCB.corp.ad.wrs.com (ala-hcb.corp.ad.wrs.com [147.11.189.41]) by mail1.windriver.com (8.15.2/8.15.2) with ESMTPS id 0617UigY016025 (version=TLSv1 cipher=DHE-RSA-AES256-SHA bits=256 verify=FAIL); Wed, 1 Jul 2020 00:30:45 -0700 (PDT) Received: from pek-lpg-core1-vm1.wrs.com (128.224.156.106) by ALA-HCB.corp.ad.wrs.com (147.11.189.41) with Microsoft SMTP Server id 14.3.487.0; Wed, 1 Jul 2020 00:30:25 -0700 From: To: CC: , Subject: [PATCH v2] usb: gadget: function: printer: Interface is disabled and returns error Date: Tue, 30 Jun 2020 13:44:07 +0800 Message-ID: <20200630054407.33165-1-qiang.zhang@windriver.com> X-Mailer: git-send-email 2.24.1 MIME-Version: 1.0 Sender: linux-usb-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-usb@vger.kernel.org From: Zqiang After the device is disconnected from the host side, the interface of the device is reset. If the userspace operates the device again, an error code should be returned. Acked-by: Felipe Balbi Signed-off-by: Zqiang --- drivers/usb/gadget/function/f_printer.c | 36 +++++++++++++++++++++++++ 1 file changed, 36 insertions(+) diff --git a/drivers/usb/gadget/function/f_printer.c b/drivers/usb/gadget/function/f_printer.c index 9c7ed2539ff7..2b45a61e4213 100644 --- a/drivers/usb/gadget/function/f_printer.c +++ b/drivers/usb/gadget/function/f_printer.c @@ -338,6 +338,11 @@ printer_open(struct inode *inode, struct file *fd) spin_lock_irqsave(&dev->lock, flags); + if (dev->interface < 0) { + spin_unlock_irqrestore(&dev->lock, flags); + return -ENODEV; + } + if (!dev->printer_cdev_open) { dev->printer_cdev_open = 1; fd->private_data = dev; @@ -430,6 +435,12 @@ printer_read(struct file *fd, char __user *buf, size_t len, loff_t *ptr) mutex_lock(&dev->lock_printer_io); spin_lock_irqsave(&dev->lock, flags); + if (dev->interface < 0) { + spin_unlock_irqrestore(&dev->lock, flags); + mutex_unlock(&dev->lock_printer_io); + return -ENODEV; + } + /* We will use this flag later to check if a printer reset happened * after we turn interrupts back on. */ @@ -561,6 +572,12 @@ printer_write(struct file *fd, const char __user *buf, size_t len, loff_t *ptr) mutex_lock(&dev->lock_printer_io); spin_lock_irqsave(&dev->lock, flags); + if (dev->interface < 0) { + spin_unlock_irqrestore(&dev->lock, flags); + mutex_unlock(&dev->lock_printer_io); + return -ENODEV; + } + /* Check if a printer reset happens while we have interrupts on */ dev->reset_printer = 0; @@ -667,6 +684,13 @@ printer_fsync(struct file *fd, loff_t start, loff_t end, int datasync) inode_lock(inode); spin_lock_irqsave(&dev->lock, flags); + + if (dev->interface < 0) { + spin_unlock_irqrestore(&dev->lock, flags); + inode_unlock(inode); + return -ENODEV; + } + tx_list_empty = (likely(list_empty(&dev->tx_reqs))); spin_unlock_irqrestore(&dev->lock, flags); @@ -689,6 +713,13 @@ printer_poll(struct file *fd, poll_table *wait) mutex_lock(&dev->lock_printer_io); spin_lock_irqsave(&dev->lock, flags); + + if (dev->interface < 0) { + spin_unlock_irqrestore(&dev->lock, flags); + mutex_unlock(&dev->lock_printer_io); + return EPOLLERR | EPOLLHUP; + } + setup_rx_reqs(dev); spin_unlock_irqrestore(&dev->lock, flags); mutex_unlock(&dev->lock_printer_io); @@ -722,6 +753,11 @@ printer_ioctl(struct file *fd, unsigned int code, unsigned long arg) spin_lock_irqsave(&dev->lock, flags); + if (dev->interface < 0) { + spin_unlock_irqrestore(&dev->lock, flags); + return -ENODEV; + } + switch (code) { case GADGET_GET_PRINTER_STATUS: status = (int)dev->printer_status;