From patchwork Sun Jun 28 01:57:31 2020 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: "Zhang, Qiang" X-Patchwork-Id: 11629879 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 2EB13618 for ; Sun, 28 Jun 2020 01:47:53 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 203A420768 for ; Sun, 28 Jun 2020 01:47:53 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1726607AbgF1Brl (ORCPT ); Sat, 27 Jun 2020 21:47:41 -0400 Received: from mail1.windriver.com ([147.11.146.13]:37707 "EHLO mail1.windriver.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726378AbgF1Brl (ORCPT ); Sat, 27 Jun 2020 21:47:41 -0400 Received: from ALA-HCA.corp.ad.wrs.com (ala-hca.corp.ad.wrs.com [147.11.189.40]) by mail1.windriver.com (8.15.2/8.15.2) with ESMTPS id 05S1lQp5013284 (version=TLSv1 cipher=DHE-RSA-AES256-SHA bits=256 verify=FAIL); Sat, 27 Jun 2020 18:47:26 -0700 (PDT) Received: from pek-lpg-core1-vm1.wrs.com (128.224.156.106) by ALA-HCA.corp.ad.wrs.com (147.11.189.40) with Microsoft SMTP Server id 14.3.487.0; Sat, 27 Jun 2020 18:47:10 -0700 From: To: CC: , , Subject: [PATCH] usb: gadget: function: printer: The device interface is reset and should return error code Date: Sun, 28 Jun 2020 09:57:31 +0800 Message-ID: <20200628015731.16566-1-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. 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;