Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1752487AbbFNOv7 (ORCPT ); Sun, 14 Jun 2015 10:51:59 -0400 Received: from mx1.redhat.com ([209.132.183.28]:38264 "EHLO mx1.redhat.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751615AbbFNOvu (ORCPT ); Sun, 14 Jun 2015 10:51:50 -0400 From: Jes Sorensen To: Nicholas Mc Guire Cc: Nicholas Mc Guire , Larry Finger , Greg Kroah-Hartman , Roberta Dobrescu , Joe Perches , Daniele Alessandrelli , Aleh Suprunovich , linux-wireless@vger.kernel.org, devel@driverdev.osuosl.org, linux-kernel@vger.kernel.org Subject: Re: [BUG ?] staging: rtl8723au: condition with no effect References: <1434191497-5611-1-git-send-email-hofrat@osadl.org> <20150614061941.GA27959@opentech.at> Date: Sun, 14 Jun 2015 10:51:46 -0400 In-Reply-To: <20150614061941.GA27959@opentech.at> (Nicholas Mc Guire's message of "Sun, 14 Jun 2015 08:19:41 +0200") Message-ID: User-Agent: Gnus/5.13 (Gnus v5.13) Emacs/24.5 (gnu/linux) MIME-Version: 1.0 Content-Type: text/plain Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 2295 Lines: 48 Nicholas Mc Guire writes: > On Sat, 13 Jun 2015, Jes Sorensen wrote: > >> Nicholas Mc Guire writes: >> > scanning for trivial bug-patters with coccinelle spatches returned: >> > ./drivers/staging/rtl8723au/hal/rtl8723a_hal_init.c:1395 >> > WARNING: condition with no effect (if branch == else) >> > >> > drivers/staging/rtl8723au/hal/rtl8723a_hal_init.c - line numbers >> > from 4.1-rc7 >> > 1395 if (bWithoutHWSM) { >> > 1396 /* value16 |= (APDM_HOST | FSM_HSUS |/PFM_ALDN); */ >> > 1397 /* 2010/08/31 According to Filen description, we need to >> > 1398 use HW to shut down 8051 automatically. */ >> > 1399 /* Because suspend operation need the asistance of 8051 >> > 1400 to wait for 3ms. */ >> > 1401 value16 = APDM_HOST | AFSM_HSUS | PFM_ALDN; >> > 1402 } else { >> > 1403 value16 = APDM_HOST | AFSM_HSUS | PFM_ALDN; >> > 1404 } >> > 1405 >> > 1406 rtl8723au_write16(padapter, REG_APS_FSMCO, value16); /* 0x4802 */ >> > >> > Not clear what the intent is but this looks like a typo/bug in the assigment >> > of value16 as the condition here has no effect. >> >> Doesn't look like a typo, looks like someone at some point had commented >> out PFM_ALDN in the bWithoutHWSM case. Why they did that and then later >> overrode it, I have no idea. >> > as far as its traceable in git log if == else was in there from the > very beginning (including that comment) - both the if and else were > updated in commit cffca68d7b2f ("staging: rtl8723au: _DisableAnalog(): Avoid > zero-init variables unnecessaril") but without changing PFM_ALDN - as there > are no comments to the meaning of these bits in the header file there is > no way to really come up with a resonable patch. anyway its either wrong > settings or the condition should be removed. There's a much longer history of this code going back to the vendor origin - it shouldn't be removed unless we can get clarification from them why that was. Jes -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/