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=-6.8 required=3.0 tests=DKIMWL_WL_HIGH,DKIM_SIGNED, DKIM_VALID,HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_PATCH,MAILING_LIST_MULTI, SIGNED_OFF_BY,SPF_HELO_NONE,SPF_PASS,URIBL_BLOCKED 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 B57E3C433DF for ; Sat, 4 Jul 2020 06:04:52 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 8FB9F208D5 for ; Sat, 4 Jul 2020 06:04:52 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1593842692; bh=/8vSxFn9V0oswGlBEN5dRRU1JZ7ExkRloN1fTwm5oNE=; h=Date:From:To:Cc:Subject:References:In-Reply-To:List-ID:From; b=lf/54FuRMjiAIssUD1vYO2GGAXg704NPqG8Iunf4TDHnmFN/cp6Bn+ROY1MHoe2fP IH3Q3XgWGrnB1SrAVf64guDtfQJAg6XcgjfEHclTBiYAymJNIfpumiTMgE4laeuQDV EedoDMu0i62s9PnJ1Jj95EP6HMFyEso4fhbB6amE= Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1727071AbgGDGEv (ORCPT ); Sat, 4 Jul 2020 02:04:51 -0400 Received: from mail.kernel.org ([198.145.29.99]:54594 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1725822AbgGDGEu (ORCPT ); Sat, 4 Jul 2020 02:04:50 -0400 Received: from localhost (83-86-89-107.cable.dynamic.v4.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 B1DCC207D4; Sat, 4 Jul 2020 06:04:49 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1593842690; bh=/8vSxFn9V0oswGlBEN5dRRU1JZ7ExkRloN1fTwm5oNE=; h=Date:From:To:Cc:Subject:References:In-Reply-To:From; b=iItwMtHdFCkvptr3+wC5oBSGGXbOgDNx2gPwmgsCTOB9hZaNp9x1NukOjke8PsoZm LU6UKJAFh7leBTlINaLmf8/tik/QF8IhaHYbr1woCmpOwenN8aJ6AMdSu0uNm3QREh su1Am+O/L4hv41K8lDOtafcHW541qbu7l2T4hx4A= Date: Sat, 4 Jul 2020 08:04:46 +0200 From: Greg KH To: Lee Jones Cc: Minas Harutyunyan , "linux-arm-kernel@lists.infradead.org" , "linux-kernel@vger.kernel.org" , "linux-usb@vger.kernel.org" , Ben Dooks Subject: Re: [PATCH 11/30] usb: dwc2: gadget: Avoid pointless read of EP control register Message-ID: <20200704060446.GA20254@kroah.com> References: <20200702144625.2533530-1-lee.jones@linaro.org> <20200702144625.2533530-12-lee.jones@linaro.org> <20200703072926.GA2322133@kroah.com> <20200703171626.GC2743379@dell> MIME-Version: 1.0 Content-Type: text/plain; charset=utf-8 Content-Disposition: inline Content-Transfer-Encoding: 8bit In-Reply-To: <20200703171626.GC2743379@dell> Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Fri, Jul 03, 2020 at 06:16:26PM +0100, Lee Jones wrote: > On Fri, 03 Jul 2020, Minas Harutyunyan wrote: > > > Hi, > > > > On 7/3/2020 11:29 AM, Greg KH wrote: > > > On Thu, Jul 02, 2020 at 03:46:06PM +0100, Lee Jones wrote: > > >> Commit ec1f9d9f01384 ("usb: dwc2: gadget: parity fix in isochronous mode") moved > > >> these checks to dwc2_hsotg_change_ep_iso_parity() back in 2015. The assigned > > >> value hasn't been read back since. Let's remove the unnecessary H/W read. > > >> > > >> Fixes the following W=1 warning: > > >> > > >> drivers/usb/dwc2/gadget.c: In function ‘dwc2_hsotg_epint’: > > >> drivers/usb/dwc2/gadget.c:2981:6: warning: variable ‘ctrl’ set but not used [-Wunused-but-set-variable] > > >> 2981 | u32 ctrl; > > >> | ^~~~ > > >> > > >> Cc: Minas Harutyunyan > > >> Cc: Ben Dooks > > >> Signed-off-by: Lee Jones > > >> --- > > >> drivers/usb/dwc2/gadget.c | 2 -- > > >> 1 file changed, 2 deletions(-) > > >> > > >> diff --git a/drivers/usb/dwc2/gadget.c b/drivers/usb/dwc2/gadget.c > > >> index 116e6175c7a48..fa07e3fcb8841 100644 > > >> --- a/drivers/usb/dwc2/gadget.c > > >> +++ b/drivers/usb/dwc2/gadget.c > > >> @@ -2975,10 +2975,8 @@ static void dwc2_hsotg_epint(struct dwc2_hsotg *hsotg, unsigned int idx, > > >> u32 epctl_reg = dir_in ? DIEPCTL(idx) : DOEPCTL(idx); > > >> u32 epsiz_reg = dir_in ? DIEPTSIZ(idx) : DOEPTSIZ(idx); > > >> u32 ints; > > >> - u32 ctrl; > > >> > > >> ints = dwc2_gadget_read_ep_interrupts(hsotg, idx, dir_in); > > >> - ctrl = dwc2_readl(hsotg, epctl_reg); > > > > > > As you know, lots of hardware requires reads to happen to do things, so > > > are you sure it is safe to remove this read call? > > > > > > > Greg, yes, it's Ok to remove this unnecessary read which remained from > > previous implementations. > > > > Lee, please add "Fixes:" tag and resubmit v2. > > Is this suitable for Stable Greg? Does it fix something that people have ever noticed or care about? Given the age of the bug, I doubt it :) thanks, greg k-h 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=-6.8 required=3.0 tests=DKIMWL_WL_HIGH,DKIM_SIGNED, DKIM_VALID,HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_PATCH,MAILING_LIST_MULTI, SIGNED_OFF_BY,SPF_HELO_NONE,SPF_PASS,URIBL_BLOCKED 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 C07A5C433E0 for ; Sat, 4 Jul 2020 06:06:42 +0000 (UTC) Received: from merlin.infradead.org (merlin.infradead.org [205.233.59.134]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPS id 88642206B7 for ; Sat, 4 Jul 2020 06:06:42 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (2048-bit key) header.d=lists.infradead.org header.i=@lists.infradead.org header.b="l+vM2qTV"; dkim=fail reason="signature verification failed" (1024-bit key) header.d=kernel.org header.i=@kernel.org header.b="iItwMtHd" DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 88642206B7 Authentication-Results: mail.kernel.org; dmarc=none (p=none dis=none) header.from=linuxfoundation.org Authentication-Results: mail.kernel.org; spf=none smtp.mailfrom=linux-arm-kernel-bounces+linux-arm-kernel=archiver.kernel.org@lists.infradead.org DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=lists.infradead.org; s=merlin.20170209; h=Sender:Content-Transfer-Encoding: Content-Type:Cc:List-Subscribe:List-Help:List-Post:List-Archive: List-Unsubscribe:List-Id:In-Reply-To:MIME-Version:References:Message-ID: Subject:To:From:Date:Reply-To:Content-ID:Content-Description:Resent-Date: Resent-From:Resent-Sender:Resent-To:Resent-Cc:Resent-Message-ID:List-Owner; bh=XSSmSRZkU2WTkday3gzWQSh54QH8qjKIQkzbsG3zI+8=; b=l+vM2qTVcTmi8Xot3QR8QrYfM 1WuTqT3pLfo66mZMkHRTNopABz52bNSnureZOqDanNL3pj+c2gSgR6RdLLK/YotZRuUqLe256EOfu YZ2OgUQ1vBL9Ly0o51a7hJeBKonJh/LKxML6JF4UjtWsti1l1StlGegJpTdp26QuhP0iWtyV1Bt1Q 0BZ3hQiooU9y1zs5qPB42J9omw9pNlHxENAXSUARHfwFgmDtklB31orlbXT12dkNC+984Xr2MS1AA 9p3dD7SCqu90DEIPen+GHm9fkHto219Q/ivAj9a1tqdj5vpZT2Kuz1hX79RnqnBRTwYR/9LwrPH5m UmsdI+n2w==; Received: from localhost ([::1] helo=merlin.infradead.org) by merlin.infradead.org with esmtp (Exim 4.92.3 #3 (Red Hat Linux)) id 1jrbIG-0005pN-6P; Sat, 04 Jul 2020 06:04:56 +0000 Received: from mail.kernel.org ([198.145.29.99]) by merlin.infradead.org with esmtps (Exim 4.92.3 #3 (Red Hat Linux)) id 1jrbID-0005oi-1F for linux-arm-kernel@lists.infradead.org; Sat, 04 Jul 2020 06:04:54 +0000 Received: from localhost (83-86-89-107.cable.dynamic.v4.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 B1DCC207D4; Sat, 4 Jul 2020 06:04:49 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1593842690; bh=/8vSxFn9V0oswGlBEN5dRRU1JZ7ExkRloN1fTwm5oNE=; h=Date:From:To:Cc:Subject:References:In-Reply-To:From; b=iItwMtHdFCkvptr3+wC5oBSGGXbOgDNx2gPwmgsCTOB9hZaNp9x1NukOjke8PsoZm LU6UKJAFh7leBTlINaLmf8/tik/QF8IhaHYbr1woCmpOwenN8aJ6AMdSu0uNm3QREh su1Am+O/L4hv41K8lDOtafcHW541qbu7l2T4hx4A= Date: Sat, 4 Jul 2020 08:04:46 +0200 From: Greg KH To: Lee Jones Subject: Re: [PATCH 11/30] usb: dwc2: gadget: Avoid pointless read of EP control register Message-ID: <20200704060446.GA20254@kroah.com> References: <20200702144625.2533530-1-lee.jones@linaro.org> <20200702144625.2533530-12-lee.jones@linaro.org> <20200703072926.GA2322133@kroah.com> <20200703171626.GC2743379@dell> MIME-Version: 1.0 Content-Disposition: inline In-Reply-To: <20200703171626.GC2743379@dell> X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.8.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20200704_020453_160702_36108326 X-CRM114-Status: GOOD ( 20.22 ) X-BeenThere: linux-arm-kernel@lists.infradead.org X-Mailman-Version: 2.1.29 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Cc: Ben Dooks , "linux-usb@vger.kernel.org" , Minas Harutyunyan , "linux-arm-kernel@lists.infradead.org" , "linux-kernel@vger.kernel.org" Content-Type: text/plain; charset="utf-8" Content-Transfer-Encoding: base64 Sender: "linux-arm-kernel" Errors-To: linux-arm-kernel-bounces+linux-arm-kernel=archiver.kernel.org@lists.infradead.org T24gRnJpLCBKdWwgMDMsIDIwMjAgYXQgMDY6MTY6MjZQTSArMDEwMCwgTGVlIEpvbmVzIHdyb3Rl Ogo+IE9uIEZyaSwgMDMgSnVsIDIwMjAsIE1pbmFzIEhhcnV0eXVueWFuIHdyb3RlOgo+IAo+ID4g SGksCj4gPiAKPiA+IE9uIDcvMy8yMDIwIDExOjI5IEFNLCBHcmVnIEtIIHdyb3RlOgo+ID4gPiBP biBUaHUsIEp1bCAwMiwgMjAyMCBhdCAwMzo0NjowNlBNICswMTAwLCBMZWUgSm9uZXMgd3JvdGU6 Cj4gPiA+PiBDb21taXQgZWMxZjlkOWYwMTM4NCAoInVzYjogZHdjMjogZ2FkZ2V0OiBwYXJpdHkg Zml4IGluIGlzb2Nocm9ub3VzIG1vZGUiKSBtb3ZlZAo+ID4gPj4gdGhlc2UgY2hlY2tzIHRvIGR3 YzJfaHNvdGdfY2hhbmdlX2VwX2lzb19wYXJpdHkoKSBiYWNrIGluIDIwMTUuICBUaGUgYXNzaWdu ZWQKPiA+ID4+IHZhbHVlIGhhc24ndCBiZWVuIHJlYWQgYmFjayBzaW5jZS4gIExldCdzIHJlbW92 ZSB0aGUgdW5uZWNlc3NhcnkgSC9XIHJlYWQuCj4gPiA+Pgo+ID4gPj4gRml4ZXMgdGhlIGZvbGxv d2luZyBXPTEgd2FybmluZzoKPiA+ID4+Cj4gPiA+PiAgIGRyaXZlcnMvdXNiL2R3YzIvZ2FkZ2V0 LmM6IEluIGZ1bmN0aW9uIOKAmGR3YzJfaHNvdGdfZXBpbnTigJk6Cj4gPiA+PiAgIGRyaXZlcnMv dXNiL2R3YzIvZ2FkZ2V0LmM6Mjk4MTo2OiB3YXJuaW5nOiB2YXJpYWJsZSDigJhjdHJs4oCZIHNl dCBidXQgbm90IHVzZWQgWy1XdW51c2VkLWJ1dC1zZXQtdmFyaWFibGVdCj4gPiA+PiAgIDI5ODEg fCB1MzIgY3RybDsKPiA+ID4+ICAgfCBefn5+Cj4gPiA+Pgo+ID4gPj4gQ2M6IE1pbmFzIEhhcnV0 eXVueWFuIDxobWluYXNAc3lub3BzeXMuY29tPgo+ID4gPj4gQ2M6IEJlbiBEb29rcyA8YmVuQHNp bXRlYy5jby51az4KPiA+ID4+IFNpZ25lZC1vZmYtYnk6IExlZSBKb25lcyA8bGVlLmpvbmVzQGxp bmFyby5vcmc+Cj4gPiA+PiAtLS0KPiA+ID4+ICAgZHJpdmVycy91c2IvZHdjMi9nYWRnZXQuYyB8 IDIgLS0KPiA+ID4+ICAgMSBmaWxlIGNoYW5nZWQsIDIgZGVsZXRpb25zKC0pCj4gPiA+Pgo+ID4g Pj4gZGlmZiAtLWdpdCBhL2RyaXZlcnMvdXNiL2R3YzIvZ2FkZ2V0LmMgYi9kcml2ZXJzL3VzYi9k d2MyL2dhZGdldC5jCj4gPiA+PiBpbmRleCAxMTZlNjE3NWM3YTQ4Li5mYTA3ZTNmY2I4ODQxIDEw MDY0NAo+ID4gPj4gLS0tIGEvZHJpdmVycy91c2IvZHdjMi9nYWRnZXQuYwo+ID4gPj4gKysrIGIv ZHJpdmVycy91c2IvZHdjMi9nYWRnZXQuYwo+ID4gPj4gQEAgLTI5NzUsMTAgKzI5NzUsOCBAQCBz dGF0aWMgdm9pZCBkd2MyX2hzb3RnX2VwaW50KHN0cnVjdCBkd2MyX2hzb3RnICpoc290ZywgdW5z aWduZWQgaW50IGlkeCwKPiA+ID4+ICAgCXUzMiBlcGN0bF9yZWcgPSBkaXJfaW4gPyBESUVQQ1RM KGlkeCkgOiBET0VQQ1RMKGlkeCk7Cj4gPiA+PiAgIAl1MzIgZXBzaXpfcmVnID0gZGlyX2luID8g RElFUFRTSVooaWR4KSA6IERPRVBUU0laKGlkeCk7Cj4gPiA+PiAgIAl1MzIgaW50czsKPiA+ID4+ IC0JdTMyIGN0cmw7Cj4gPiA+PiAgIAo+ID4gPj4gICAJaW50cyA9IGR3YzJfZ2FkZ2V0X3JlYWRf ZXBfaW50ZXJydXB0cyhoc290ZywgaWR4LCBkaXJfaW4pOwo+ID4gPj4gLQljdHJsID0gZHdjMl9y ZWFkbChoc290ZywgZXBjdGxfcmVnKTsKPiA+ID4gCj4gPiA+IEFzIHlvdSBrbm93LCBsb3RzIG9m IGhhcmR3YXJlIHJlcXVpcmVzIHJlYWRzIHRvIGhhcHBlbiB0byBkbyB0aGluZ3MsIHNvCj4gPiA+ IGFyZSB5b3Ugc3VyZSBpdCBpcyBzYWZlIHRvIHJlbW92ZSB0aGlzIHJlYWQgY2FsbD8KPiA+ID4g Cj4gPiAKPiA+IEdyZWcsIHllcywgaXQncyBPayB0byByZW1vdmUgdGhpcyB1bm5lY2Vzc2FyeSBy ZWFkIHdoaWNoIHJlbWFpbmVkIGZyb20gCj4gPiBwcmV2aW91cyBpbXBsZW1lbnRhdGlvbnMuCj4g PiAKPiA+IExlZSwgcGxlYXNlIGFkZCAiRml4ZXM6IiB0YWcgYW5kIHJlc3VibWl0IHYyLgo+IAo+ IElzIHRoaXMgc3VpdGFibGUgZm9yIFN0YWJsZSBHcmVnPwoKRG9lcyBpdCBmaXggc29tZXRoaW5n IHRoYXQgcGVvcGxlIGhhdmUgZXZlciBub3RpY2VkIG9yIGNhcmUgYWJvdXQ/CkdpdmVuIHRoZSBh Z2Ugb2YgdGhlIGJ1ZywgSSBkb3VidCBpdCA6KQoKdGhhbmtzLAoKZ3JlZyBrLWgKCl9fX19fX19f X19fX19fX19fX19fX19fX19fX19fX19fX19fX19fX19fX19fX19fCmxpbnV4LWFybS1rZXJuZWwg bWFpbGluZyBsaXN0CmxpbnV4LWFybS1rZXJuZWxAbGlzdHMuaW5mcmFkZWFkLm9yZwpodHRwOi8v bGlzdHMuaW5mcmFkZWFkLm9yZy9tYWlsbWFuL2xpc3RpbmZvL2xpbnV4LWFybS1rZXJuZWwK