From patchwork Wed Jul 18 08:45:48 2018 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Guido Kiener X-Patchwork-Id: 10531549 Return-Path: Received: from mail.wl.linuxfoundation.org (pdx-wl-mail.web.codeaurora.org [172.30.200.125]) by pdx-korg-patchwork.web.codeaurora.org (Postfix) with ESMTP id 4376960633 for ; Wed, 18 Jul 2018 07:54:10 +0000 (UTC) Received: from mail.wl.linuxfoundation.org (localhost [127.0.0.1]) by mail.wl.linuxfoundation.org (Postfix) with ESMTP id 347E3291C6 for ; Wed, 18 Jul 2018 07:54:10 +0000 (UTC) Received: by mail.wl.linuxfoundation.org (Postfix, from userid 486) id 28AA2291C8; Wed, 18 Jul 2018 07:54:10 +0000 (UTC) X-Spam-Checker-Version: SpamAssassin 3.3.1 (2010-03-16) on pdx-wl-mail.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-7.9 required=2.0 tests=BAYES_00, MAILING_LIST_MULTI, RCVD_IN_DNSWL_HI autolearn=ham version=3.3.1 Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.wl.linuxfoundation.org (Postfix) with ESMTP id A452D291C7 for ; Wed, 18 Jul 2018 07:54:09 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1729698AbeGRIao (ORCPT ); Wed, 18 Jul 2018 04:30:44 -0400 Received: from mr07.mx01.tldhost.de ([62.108.44.247]:58734 "EHLO mr07.mx01.tldhost.de" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1729180AbeGRIan (ORCPT ); Wed, 18 Jul 2018 04:30:43 -0400 Received: from mx01.tldhost.de (localhost [127.0.0.1]) by mx01.tldhost.de (Postfix) with ESMTP id 3CD0F120EED for ; Wed, 18 Jul 2018 09:48:18 +0200 (CEST) Received: by mx01.tldhost.de (Postfix, from userid 1001) id 32F73120ED0; Wed, 18 Jul 2018 09:48:18 +0200 (CEST) Received: from server12.tldhost.de (server12.tldhost.de [84.19.26.112]) by mx01.tldhost.de (Postfix) with ESMTPS id 24119120EE9; Wed, 18 Jul 2018 09:48:16 +0200 (CEST) From: Guido Kiener To: gregkh@linuxfoundation.org, linux-usb@vger.kernel.org, guido.kiener@rohde-schwarz.com, steve_bayless@keysight.com, dpenkler@gmail.com Cc: Guido Kiener Subject: [PATCH v2 15/29] usb: usbtmc: Add ioctl USBTMC488_IOCTL_WAIT_SRQ Date: Wed, 18 Jul 2018 10:45:48 +0200 Message-Id: <20180718084602.10568-16-guido@kiener-muenchen.de> In-Reply-To: <20180718084602.10568-1-guido@kiener-muenchen.de> References: <20180718084602.10568-1-guido@kiener-muenchen.de> X-PPP-Message-ID: <20180718074816.13309.8376@server12.tldhost.de> X-PPP-Vhost: kiener-muenchen.de X-POWERED-BY: TLDHost.de - AV:CLEAN SPAM:OK Sender: linux-usb-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-usb@vger.kernel.org X-Virus-Scanned: ClamAV using ClamSMTP Wait until an SRQ (service request) is received on the interrupt pipe or until the given period of time is expired. In contrast to the poll() function this ioctl does not return when other (a)synchronous I/O operations fail with EPOLLERR. Signed-off-by: Guido Kiener Reviewed-by: Steve Bayless --- drivers/usb/class/usbtmc.c | 57 ++++++++++++++++++++++++++++++++++++ include/uapi/linux/usb/tmc.h | 1 + 2 files changed, 58 insertions(+) diff --git a/drivers/usb/class/usbtmc.c b/drivers/usb/class/usbtmc.c index 71c81ceaf7e7..8ab8c6f33cec 100644 --- a/drivers/usb/class/usbtmc.c +++ b/drivers/usb/class/usbtmc.c @@ -130,6 +130,7 @@ struct usbtmc_file_data { u32 timeout; u8 srq_byte; atomic_t srq_asserted; + atomic_t closing; u8 eom_val; u8 term_char; @@ -213,6 +214,8 @@ static int usbtmc_open(struct inode *inode, struct file *filp) mutex_lock(&data->io_mutex); file_data->data = data; + atomic_set(&file_data->closing, 0); + /* copy default values from device settings */ file_data->timeout = USBTMC_TIMEOUT; file_data->term_char = data->TermChar; @@ -243,6 +246,7 @@ static int usbtmc_flush(struct file *file, fl_owner_t id) if (file_data == NULL) return -ENODEV; + atomic_set(&file_data->closing, 1); data = file_data->data; /* wait for io to stop */ @@ -596,6 +600,54 @@ static int usbtmc488_ioctl_read_stb(struct usbtmc_file_data *file_data, return rv; } +static int usbtmc488_ioctl_wait_srq(struct usbtmc_file_data *file_data, + __u32 __user *arg) +{ + struct usbtmc_device_data *data = file_data->data; + struct device *dev = &data->intf->dev; + int rv; + u32 timeout; + unsigned long expire; + + if (!data->iin_ep_present) { + dev_dbg(dev, "no interrupt endpoint present\n"); + return -EFAULT; + } + + if (get_user(timeout, arg)) + return -EFAULT; + + expire = msecs_to_jiffies(timeout); + + mutex_unlock(&data->io_mutex); + + rv = wait_event_interruptible_timeout( + data->waitq, + atomic_read(&file_data->srq_asserted) != 0 || + atomic_read(&file_data->closing), + expire); + + mutex_lock(&data->io_mutex); + + /* Note! disconnect or close could be called in the meantime */ + if (atomic_read(&file_data->closing) || data->zombie) + rv = -ENODEV; + + if (rv < 0) { + /* dev can be invalid now! */ + pr_debug("%s - wait interrupted %d\n", __func__, rv); + return rv; + } + + if (rv == 0) { + dev_dbg(dev, "%s - wait timed out\n", __func__); + return -ETIMEDOUT; + } + + dev_dbg(dev, "%s - srq asserted\n", __func__); + return 0; +} + static int usbtmc488_ioctl_simple(struct usbtmc_device_data *data, void __user *arg, unsigned int cmd) { @@ -2290,6 +2342,11 @@ static long usbtmc_ioctl(struct file *file, unsigned int cmd, unsigned long arg) retval = usbtmc488_ioctl_trigger(file_data); break; + case USBTMC488_IOCTL_WAIT_SRQ: + retval = usbtmc488_ioctl_wait_srq(file_data, + (__u32 __user *)arg); + break; + case USBTMC_IOCTL_CANCEL_IO: retval = usbtmc_ioctl_cancel_io(file_data); break; diff --git a/include/uapi/linux/usb/tmc.h b/include/uapi/linux/usb/tmc.h index 60da62e02d9c..76d11af19aaa 100644 --- a/include/uapi/linux/usb/tmc.h +++ b/include/uapi/linux/usb/tmc.h @@ -96,6 +96,7 @@ struct usbtmc_message { #define USBTMC488_IOCTL_GOTO_LOCAL _IO(USBTMC_IOC_NR, 20) #define USBTMC488_IOCTL_LOCAL_LOCKOUT _IO(USBTMC_IOC_NR, 21) #define USBTMC488_IOCTL_TRIGGER _IO(USBTMC_IOC_NR, 22) +#define USBTMC488_IOCTL_WAIT_SRQ _IOW(USBTMC_IOC_NR, 23, __u32) /* Cancel and cleanup asynchronous calls */ #define USBTMC_IOCTL_CANCEL_IO _IO(USBTMC_IOC_NR, 35)