From mboxrd@z Thu Jan 1 00:00:00 1970 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: base64 Subject: [-next] usb: ftdi-elan: Fix if == else warnings in ftdi_elan_respond_engine From: Greg Kroah-Hartman Message-Id: <20190123134147.GC24700@kroah.com> Date: Wed, 23 Jan 2019 14:41:48 +0100 To: YueHaibing Cc: linux-kernel@vger.kernel.org, linux-usb@vger.kernel.org List-ID: T24gV2VkLCBKYW4gMjMsIDIwMTkgYXQgMDk6MTc6MzhQTSArMDgwMCwgWXVlSGFpYmluZyB3cm90 ZToKPiBPbiAyMDE5LzEvMjMgMjA6NDMsIEdyZWcgS0ggd3JvdGU6Cj4gPiBPbiBXZWQsIEphbiAy MywgMjAxOSBhdCAwODozNDo0MlBNICswODAwLCBZdWVIYWliaW5nIHdyb3RlOgo+ID4+IC4vZHJp dmVycy91c2IvbWlzYy9mdGRpLWVsYW4uYzo5NzI6MTAtMTI6IFdBUk5JTkc6IHBvc3NpYmxlIGNv bmRpdGlvbiB3aXRoIG5vIGVmZmVjdCAoaWYgPT0gZWxzZSkKPiA+PiAuL2RyaXZlcnMvdXNiL21p c2MvZnRkaS1lbGFuLmM6OTgzOjktMTE6IFdBUk5JTkc6IHBvc3NpYmxlIGNvbmRpdGlvbiB3aXRo IG5vIGVmZmVjdCAoaWYgPT0gZWxzZSkKPiA+PiAuL2RyaXZlcnMvdXNiL21pc2MvZnRkaS1lbGFu LmM6MjA1MjoxMS0xMzogV0FSTklORzogcG9zc2libGUgY29uZGl0aW9uIHdpdGggbm8gZWZmZWN0 IChpZiA9PSBlbHNlKQo+ID4+Cj4gPj4gU2lnbmVkLW9mZi1ieTogWXVlSGFpYmluZyA8eXVlaGFp YmluZ0BodWF3ZWkuY29tPgo+ID4gCj4gPiBZb3UgY2FuIG5vdCBqdXN0IHByb3ZpZGUgdGhlIG91 dHB1dCBvZiBhIHRvb2wgYXMgYSBjaGFuZ2Vsb2cgdGV4dCwKPiA+IHNvcnJ5Lgo+ID4gCj4gPiBQ bGVhc2UgZXhwbGFpbiB3aGF0IHRob3NlIGxpbmVzIG1lYW4sIGFuZCB3aHkgeW91IGFyZSBtYWtp bmcgdGhlIGNoYW5nZQo+ID4gdGhhdCB5b3UgYXJlLgo+IAo+IG9rLCB3aWxsIGRvIHRoYXQuCj4g Cj4gPiAKPiA+PiAtLS0KPiA+PiAgZHJpdmVycy91c2IvbWlzYy9mdGRpLWVsYW4uYyB8IDI2IC0t LS0tLS0tLS0tLS0tLS0tLS0tLS0tLS0tCj4gPj4gIDEgZmlsZSBjaGFuZ2VkLCAyNiBkZWxldGlv bnMoLSkKPiA+Pgo+ID4+IGRpZmYgLS1naXQgYS9kcml2ZXJzL3VzYi9taXNjL2Z0ZGktZWxhbi5j IGIvZHJpdmVycy91c2IvbWlzYy9mdGRpLWVsYW4uYwo+ID4+IGluZGV4IDc2YzcxOGEuLjI1N2Vm YWMgMTAwNjQ0Cj4gPj4gLS0tIGEvZHJpdmVycy91c2IvbWlzYy9mdGRpLWVsYW4uYwo+ID4+ICsr KyBiL2RyaXZlcnMvdXNiL21pc2MvZnRkaS1lbGFuLmMKPiA+PiBAQCAtOTE1LDcgKzkxNSw2IEBA IHN0YXRpYyBpbnQgZnRkaV9lbGFuX3Jlc3BvbmRfZW5naW5lKHN0cnVjdCB1c2JfZnRkaSAqZnRk aSkKPiA+PiAgCWludCBieXRlc19yZWFkID0gMDsKPiA+PiAgCWludCByZXRyeV9vbl9lbXB0eSA9 IDE7Cj4gPj4gIAlpbnQgcmV0cnlfb25fdGltZW91dCA9IDM7Cj4gPj4gLQlpbnQgZW1wdHlfcGFj a2V0cyA9IDA7Cj4gPj4gIHJlYWQ6ewo+ID4+ICAJCWludCBwYWNrZXRfYnl0ZXMgPSAwOwo+ID4+ ICAJCWludCByZXR2YWwgPSB1c2JfYnVsa19tc2coZnRkaS0+dWRldiwKPiA+PiBAQCAtOTYwLDMx ICs5NTksNiBAQCByZWFkOnsKPiA+PiAgCQkJZGV2X2VycigmZnRkaS0+dWRldi0+ZGV2LCAiZXJy b3IgPSAlZCB3aXRoIHBhY2tldF9ieXRlcyA9ICVkIHdpdGggdG90YWwgJWQgYnl0ZXMlc1xuIiwK PiA+PiAgCQkJCXJldHZhbCwgcGFja2V0X2J5dGVzLCBieXRlc19yZWFkLCBkaWFnKTsKPiA+PiAg CQkJcmV0dXJuIHJldHZhbDsKPiA+PiAtCQl9IGVsc2UgaWYgKHBhY2tldF9ieXRlcyA9PSAyKSB7 Cj4gPj4gLQkJCXVuc2lnbmVkIGNoYXIgczAgPSBmdGRpLT5idWxrX2luX2J1ZmZlclswXTsKPiA+ PiAtCQkJdW5zaWduZWQgY2hhciBzMSA9IGZ0ZGktPmJ1bGtfaW5fYnVmZmVyWzFdOwo+ID4+IC0J CQllbXB0eV9wYWNrZXRzICs9IDE7Cj4gPj4gLQkJCWlmIChzMCA9PSAweDMxICYmIHMxID09IDB4 NjApIHsKPiA+PiAtCQkJCWlmIChyZXRyeV9vbl9lbXB0eS0tID4gMCkgewo+ID4+IC0JCQkJCWdv dG8gbW9yZTsKPiA+PiAtCQkJCX0gZWxzZQo+ID4+IC0JCQkJCXJldHVybiAwOwo+ID4+IC0JCQl9 IGVsc2UgaWYgKHMwID09IDB4MzEgJiYgczEgPT0gMHgwMCkgewo+ID4+IC0JCQkJaWYgKHJldHJ5 X29uX2VtcHR5LS0gPiAwKSB7Cj4gPj4gLQkJCQkJZ290byBtb3JlOwo+ID4+IC0JCQkJfSBlbHNl Cj4gPj4gLQkJCQkJcmV0dXJuIDA7Cj4gPj4gLQkJCX0gZWxzZSB7Cj4gPj4gLQkJCQlpZiAocmV0 cnlfb25fZW1wdHktLSA+IDApIHsKPiA+PiAtCQkJCQlnb3RvIG1vcmU7Cj4gPj4gLQkJCQl9IGVs c2UKPiA+PiAtCQkJCQlyZXR1cm4gMDsKPiA+PiAtCQkJfQo+ID4+IC0JCX0gZWxzZSBpZiAocGFj a2V0X2J5dGVzID09IDEpIHsKPiA+PiAtCQkJaWYgKHJldHJ5X29uX2VtcHR5LS0gPiAwKSB7Cj4g Pj4gLQkJCQlnb3RvIG1vcmU7Cj4gPj4gLQkJCX0gZWxzZQo+ID4+IC0JCQkJcmV0dXJuIDA7Cj4g PiAKPiA+IEFyZSB5b3UgX3N1cmVfIHRoYXQgdGhlc2UgbGluZXMgYXJlIG5vdCBuZWVkZWQgYW5k IHRoYXQgdGhlIGNvbXBpbGVyIGlzCj4gPiBub3QgcmVhbGx5IHNlZWluZyB0aGVtPyAgQXMgaXQg ZG9lc24ndCBsb29rIHRoYXQgd2F5IHRvIG1lLCB3aGF0IGFtIEkKPiA+IG1pc3Npbmc/Cj4gCj4g SSBjaGVja2VkIGFuZCBtYWtlIHN1cmUgdGhhdCBBbGwgdGhlc2UgaWYvZWxzZSBpZiBicmFuY2gg anVzdCBkbyB0aGUgc2FtZSB0aGluZzoKPiAKPiAJaWYgKHJldHJ5X29uX2VtcHR5LS0gPiAwKSB7 Cj4gCQlnb3RvIG1vcmU7Cj4gCX0gZWxzZQo+IAkJcmV0dXJuIDA7Cj4gCj4gc28gaXQgY2FuIGJl IG1lcmdlZCBpbnRvIHRoZSBsYXN0IGVsc2UgYnJhbmNoLgo+IAo+IEFsc28gdGhlIHZhcmlhYmxl ICdlbXB0eV9wYWNrZXRzJyBkb2Vzbid0IHVzZSBpbiBhbnkgcGxhY2UsIGV4Y2VwdCBmb3Igc2Vs ZiBpbmNyZW1lbnQKCkRvbid0IGRvIHR3byBkaWZmZXJlbnQgdGhpbmdzIGluIHRoZSBzYW1lIHBh dGNoIDopCg== 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=-9.6 required=3.0 tests=DKIMWL_WL_HIGH,DKIM_SIGNED, DKIM_VALID,HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_PATCH,MAILING_LIST_MULTI, SIGNED_OFF_BY,SPF_PASS,USER_AGENT_MUTT autolearn=ham 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 082ECC282C0 for ; Wed, 23 Jan 2019 13:41:54 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id C83902133D for ; Wed, 23 Jan 2019 13:41:53 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1548250913; bh=bhNsrBIzjCKhWx6dzhuEerxRchlI2MV0/XhG9VyGdSU=; h=Date:From:To:Cc:Subject:References:In-Reply-To:List-ID:From; b=I+A2YTW6PMZHZ6Y001HUjVNtBi5lLFD2gmbvbOBKKjO8UuxmaE4sLtobmE/xghO8q 2wOuknaElrVeMmOhElb7dAplTzzZf+ztFejWrlu/so+ePTi4v2J3YHof1NEjEAUK/i 53gGdZsQInghmbY8sXZR+d1tzdBSKfYpj7Tv7Py4= Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1726322AbfAWNlw (ORCPT ); Wed, 23 Jan 2019 08:41:52 -0500 Received: from mail.kernel.org ([198.145.29.99]:56082 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726029AbfAWNlv (ORCPT ); Wed, 23 Jan 2019 08:41:51 -0500 Received: from localhost (5356596B.cm-6-7b.dynamic.ziggo.nl [83.86.89.107]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPSA id E28BD20870; Wed, 23 Jan 2019 13:41:49 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1548250910; bh=bhNsrBIzjCKhWx6dzhuEerxRchlI2MV0/XhG9VyGdSU=; h=Date:From:To:Cc:Subject:References:In-Reply-To:From; b=a+SdaKaYT4B/rVemnsJPr85fmEkwRvBtNZnq4vq0T5LvH0EH9ikcA2zub9em5RVTE ALCsv2Iml5jxscNoUaqOSicH9n7rfjYymUoaguY+MJSS7Gyx7mIuiXtFB+sH4tA3e1 kmoCBg6Pj2PrlY7A2aELGnjhKZY03pi0XO45wBCc= Date: Wed, 23 Jan 2019 14:41:48 +0100 From: Greg KH To: YueHaibing Cc: linux-kernel@vger.kernel.org, linux-usb@vger.kernel.org Subject: Re: [PATCH -next] usb: ftdi-elan: Fix if == else warnings in ftdi_elan_respond_engine Message-ID: <20190123134147.GC24700@kroah.com> References: <20190123123442.5256-1-yuehaibing@huawei.com> <20190123124319.GB19703@kroah.com> <10d0f378-03ab-1855-1476-a39cf6b816ab@huawei.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <10d0f378-03ab-1855-1476-a39cf6b816ab@huawei.com> User-Agent: Mutt/1.11.2 (2019-01-07) Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Wed, Jan 23, 2019 at 09:17:38PM +0800, YueHaibing wrote: > On 2019/1/23 20:43, Greg KH wrote: > > On Wed, Jan 23, 2019 at 08:34:42PM +0800, YueHaibing wrote: > >> ./drivers/usb/misc/ftdi-elan.c:972:10-12: WARNING: possible condition with no effect (if == else) > >> ./drivers/usb/misc/ftdi-elan.c:983:9-11: WARNING: possible condition with no effect (if == else) > >> ./drivers/usb/misc/ftdi-elan.c:2052:11-13: WARNING: possible condition with no effect (if == else) > >> > >> Signed-off-by: YueHaibing > > > > You can not just provide the output of a tool as a changelog text, > > sorry. > > > > Please explain what those lines mean, and why you are making the change > > that you are. > > ok, will do that. > > > > >> --- > >> drivers/usb/misc/ftdi-elan.c | 26 -------------------------- > >> 1 file changed, 26 deletions(-) > >> > >> diff --git a/drivers/usb/misc/ftdi-elan.c b/drivers/usb/misc/ftdi-elan.c > >> index 76c718a..257efac 100644 > >> --- a/drivers/usb/misc/ftdi-elan.c > >> +++ b/drivers/usb/misc/ftdi-elan.c > >> @@ -915,7 +915,6 @@ static int ftdi_elan_respond_engine(struct usb_ftdi *ftdi) > >> int bytes_read = 0; > >> int retry_on_empty = 1; > >> int retry_on_timeout = 3; > >> - int empty_packets = 0; > >> read:{ > >> int packet_bytes = 0; > >> int retval = usb_bulk_msg(ftdi->udev, > >> @@ -960,31 +959,6 @@ read:{ > >> dev_err(&ftdi->udev->dev, "error = %d with packet_bytes = %d with total %d bytes%s\n", > >> retval, packet_bytes, bytes_read, diag); > >> return retval; > >> - } else if (packet_bytes == 2) { > >> - unsigned char s0 = ftdi->bulk_in_buffer[0]; > >> - unsigned char s1 = ftdi->bulk_in_buffer[1]; > >> - empty_packets += 1; > >> - if (s0 == 0x31 && s1 == 0x60) { > >> - if (retry_on_empty-- > 0) { > >> - goto more; > >> - } else > >> - return 0; > >> - } else if (s0 == 0x31 && s1 == 0x00) { > >> - if (retry_on_empty-- > 0) { > >> - goto more; > >> - } else > >> - return 0; > >> - } else { > >> - if (retry_on_empty-- > 0) { > >> - goto more; > >> - } else > >> - return 0; > >> - } > >> - } else if (packet_bytes == 1) { > >> - if (retry_on_empty-- > 0) { > >> - goto more; > >> - } else > >> - return 0; > > > > Are you _sure_ that these lines are not needed and that the compiler is > > not really seeing them? As it doesn't look that way to me, what am I > > missing? > > I checked and make sure that All these if/else if branch just do the same thing: > > if (retry_on_empty-- > 0) { > goto more; > } else > return 0; > > so it can be merged into the last else branch. > > Also the variable 'empty_packets' doesn't use in any place, except for self increment Don't do two different things in the same patch :)