From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-14.0 required=3.0 tests=BAYES_00,INCLUDES_CR_TRAILER, INCLUDES_PATCH,MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS autolearn=unavailable autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id 33DE7C433FE for ; Fri, 4 Dec 2020 09:56:24 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id E11B622795 for ; Fri, 4 Dec 2020 09:56:23 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1729143AbgLDJ4G (ORCPT ); Fri, 4 Dec 2020 04:56:06 -0500 Received: from mail-lj1-f193.google.com ([209.85.208.193]:36668 "EHLO mail-lj1-f193.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726014AbgLDJ4G (ORCPT ); Fri, 4 Dec 2020 04:56:06 -0500 Received: by mail-lj1-f193.google.com with SMTP id a1so4576182ljq.3; Fri, 04 Dec 2020 01:55:49 -0800 (PST) X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:date:from:to:cc:subject:message-id:references :mime-version:content-disposition:in-reply-to; bh=KR7bvZk9IL0aVDrbxk4V05QNkr638YolAIwhooQDGYw=; b=SLz70pkvYSPiw8T9+rXImQMdadAiemzeNeM6PtS1s3au+XWjIhvU4xDxttxoURP9Bh WGrBtDn2g5hgwGH14X74hGo4AehWSWQh/soaqyVpfDd1X0gedIcAbjnldAlSiq1nAD6+ R33QXL49+xouYo4DleuVJh5UTk4uHwSBl/vZ5ZqXJwdKPQIPDF9Jl97JtHSi9XHwC6pX D9mAiXLClsvjnwYS/VQytJ6Ar31IkQk6VX0UmaAsCMf51E7kpMOnZtMLSboCtc+dUcSs 6kSrtBlSzt705efFBn+FxkJbIEhmQGTd2tWb8n0igaQ9GkQe7cmqfpxFd+Gg5Dn8kNQq PB3g== X-Gm-Message-State: AOAM532bC4scZZixv45U9chJsUAbRclY4tAvKheZvcOPtI9hasfHfzE9 gDKTRkkDrZUjY5zaQaFLC+o= X-Google-Smtp-Source: ABdhPJwYmkZIAkj2nS8w7vSQfiok7d0nOZTQfC3LwYpXyrsx61HYASrW0XIagI6VSqfdyyUVNwyf4Q== X-Received: by 2002:a05:651c:1195:: with SMTP id w21mr3043489ljo.427.1607075724025; Fri, 04 Dec 2020 01:55:24 -0800 (PST) Received: from xi.terra (c-beaee455.07-184-6d6c6d4.bbcust.telenor.se. [85.228.174.190]) by smtp.gmail.com with ESMTPSA id f21sm1545449ljk.0.2020.12.04.01.55.23 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Fri, 04 Dec 2020 01:55:23 -0800 (PST) Received: from johan by xi.terra with local (Exim 4.93.0.4) (envelope-from ) id 1kl7oi-0005Qc-D0; Fri, 04 Dec 2020 10:55:57 +0100 Date: Fri, 4 Dec 2020 10:55:56 +0100 From: Johan Hovold To: Himadri Pandya Cc: johan@kernel.org, gregkh@linuxfoundation.org, linux-usb@vger.kernel.org, linux-kernel@vger.kernel.org, linux-kernel-mentees@lists.linuxfoundation.org Subject: Re: [PATCH 07/15] usb: serial: f81534: use usb_control_msg_recv() and usb_control_msg_send() Message-ID: References: <20201104064703.15123-1-himadrispandya@gmail.com> <20201104064703.15123-8-himadrispandya@gmail.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20201104064703.15123-8-himadrispandya@gmail.com> Precedence: bulk List-ID: X-Mailing-List: linux-usb@vger.kernel.org On Wed, Nov 04, 2020 at 12:16:55PM +0530, Himadri Pandya wrote: > The new usb_control_msg_recv() and usb_control_msg_send() nicely wraps > usb_control_msg() with proper error check. Hence use the wrappers > instead of calling usb_control_msg() directly. > > Signed-off-by: Himadri Pandya > --- > drivers/usb/serial/f81534.c | 63 +++++++++++-------------------------- > 1 file changed, 18 insertions(+), 45 deletions(-) > > diff --git a/drivers/usb/serial/f81534.c b/drivers/usb/serial/f81534.c > index 5661fd03e545..23eb17a2c052 100644 > --- a/drivers/usb/serial/f81534.c > +++ b/drivers/usb/serial/f81534.c > @@ -217,38 +217,26 @@ static int f81534_set_register(struct usb_serial *serial, u16 reg, u8 data) > struct usb_device *dev = serial->dev; > size_t count = F81534_USB_MAX_RETRY; > int status; > - u8 *tmp; > - > - tmp = kmalloc(sizeof(u8), GFP_KERNEL); > - if (!tmp) > - return -ENOMEM; > - > - *tmp = data; > > /* > * Our device maybe not reply when heavily loading, We'll retry for > * F81534_USB_MAX_RETRY times. > */ > while (count--) { > - status = usb_control_msg(dev, usb_sndctrlpipe(dev, 0), > - F81534_SET_GET_REGISTER, > - USB_TYPE_VENDOR | USB_DIR_OUT, > - reg, 0, tmp, sizeof(u8), > - F81534_USB_TIMEOUT); > - if (status > 0) { > - status = 0; > - break; > - } else if (status == 0) { > - status = -EIO; > + status = usb_control_msg_send(dev, 0, F81534_SET_GET_REGISTER, > + USB_TYPE_VENDOR | USB_DIR_OUT, > + reg, 0, &data, sizeof(u8), > + F81534_USB_TIMEOUT, GFP_KERNEL); > + if (status) { > + /* Try again */ > + continue; > } > } Here too this change breaks the logic and the control transfer is now repeated also after successful transfer (ten times!). This change would also introduce an additional malloc + memcpy for every retry. As this is a function that is used often and the comment suggest that having to retry isn't that rare, I suggest dropping this patch as well. Johan