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=-8.2 required=3.0 tests=DKIM_SIGNED,DKIM_VALID, DKIM_VALID_AU,FREEMAIL_FORGED_FROMDOMAIN,FREEMAIL_FROM, HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_PATCH,MAILING_LIST_MULTI,SIGNED_OFF_BY, SPF_HELO_NONE,SPF_PASS,USER_AGENT_SANE_1 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 04ED6FA372A for ; Thu, 17 Oct 2019 16:41:41 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id C7A0B21835 for ; Thu, 17 Oct 2019 16:41:40 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (2048-bit key) header.d=gmail.com header.i=@gmail.com header.b="U11ac5DM" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S2391079AbfJQQlk (ORCPT ); Thu, 17 Oct 2019 12:41:40 -0400 Received: from mail-lf1-f67.google.com ([209.85.167.67]:33408 "EHLO mail-lf1-f67.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1729529AbfJQQlk (ORCPT ); Thu, 17 Oct 2019 12:41:40 -0400 Received: by mail-lf1-f67.google.com with SMTP id y127so2448757lfc.0 for ; Thu, 17 Oct 2019 09:41:38 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20161025; h=date:from:to:cc:subject:message-id:references:mime-version :content-disposition:in-reply-to:user-agent; bh=9bizna7G7Om3cZn0nGwpOJh+7ANQ7i4dkTdpQcsQemg=; b=U11ac5DMRhZGtPTItC96uDP1/7ern8vUSY1yJnP3PYjGQ7MkncbdJmxx/QO3XleNvW uKiR/4P3sAKygclkhCwcjlhRpykROLBPBZcgKr5pTSsLR6ZAgWuY9FBlHg967HUejwBP 5n/fNb2IjYYtNmNNE/JnGJgUmsTedynMwFVe4HixHTcwrkbMT1//RFcP/2Oj3s+isB2a ktS4beNpeBA38JVq+Zf7pczt07Q6kFRr9jD3zMycxklP3OeubnpuAODie+vtsbyJd4+c KsIb4P/+KX08hozW4Gc7hHLWTtWqMNCWOH4lu9Gsys6793STO5s4+llRapIUWYbYc5GK oogQ== 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:user-agent; bh=9bizna7G7Om3cZn0nGwpOJh+7ANQ7i4dkTdpQcsQemg=; b=r1aexvPwv2JsC4RouKTtIbjaSztDSrMEM0hHmiGXWn/ocDOWtfLld9fUNroK+U1er1 iTUCk3bDkqUGss4IzNtn5u09tFxswIdX+ZWTOsrlcfnOS1BOY3lqC77YFnr/AB3yBAMm TYf4PfsuaZZR8Qn6D9Wsm4CPRo9qYsFUFdEh7jE/K1x3VlxAEXYwXce01Px7VfqYm7eR 3U2lczvgDD6Yp8p3XRahITXvFv+9Z/28MnsTqLLGaSeMa+IZqQWYq3YLp+vOH2uVhE5R upqVv7RCp2B2xJDpzRZ9XXn0sdw0WUeTGgxNg+CBJBUOHfO6IDYw3GSrdNX4IzBzxRvp i/5A== X-Gm-Message-State: APjAAAVWiKfN7+CmnoBzEfRMUDLF8ArCdtHvYYQxsfdoRMIghwaBjjNV IBPTC5GpI7mcPDBykYHAqGUhS+ndHVA= X-Google-Smtp-Source: APXvYqw4LQv8H1Cdp6BH1KVjhiPYaar7N842a35LQQz5klHIK0WbdiJddHe/ZpI5GdG4IccIyKm/Ww== X-Received: by 2002:ac2:5c1b:: with SMTP id r27mr2988752lfp.172.1571330497836; Thu, 17 Oct 2019 09:41:37 -0700 (PDT) Received: from localhost (89-70-31-203.dynamic.chello.pl. [89.70.31.203]) by smtp.gmail.com with ESMTPSA id q3sm1110896ljq.4.2019.10.17.09.41.36 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Thu, 17 Oct 2019 09:41:36 -0700 (PDT) Date: Thu, 17 Oct 2019 18:41:12 +0200 From: Tomasz Duszynski To: jic23@kernel.org Cc: linux-iio@vger.kernel.org, Jonathan Cameron , Tomasz Duszynski Subject: Re: [PATCH] iio: chemical: sps30: Explicity truncate constant by masking Message-ID: <20191017164112.GA5100@arch> References: <20191013095515.1438147-1-jic23@kernel.org> MIME-Version: 1.0 Content-Type: text/plain; charset=utf-8 Content-Disposition: inline In-Reply-To: <20191013095515.1438147-1-jic23@kernel.org> User-Agent: Mutt/1.12.2 (2019-09-21) Sender: linux-iio-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-iio@vger.kernel.org On Sun, Oct 13, 2019 at 10:55:15AM +0100, jic23@kernel.org wrote: > From: Jonathan Cameron > > When breaking up a constant to write to two 8 bit registers > it isn't obvious to sparse that it was intentional. > > CHECK drivers/iio/chemical/sps30.c > drivers/iio/chemical/sps30.c:120:30: warning: cast truncates bits from constant value (8004 becomes 4) > > So in the interests of minimising noisy warnings, let us add > a mask. > > Signed-off-by: Jonathan Cameron > Cc: Tomasz Duszynski > --- > drivers/iio/chemical/sps30.c | 2 +- > 1 file changed, 1 insertion(+), 1 deletion(-) > > diff --git a/drivers/iio/chemical/sps30.c b/drivers/iio/chemical/sps30.c > index edbb956e81e8..acb9f8ecbb3d 100644 > --- a/drivers/iio/chemical/sps30.c > +++ b/drivers/iio/chemical/sps30.c > @@ -117,7 +117,7 @@ static int sps30_do_cmd(struct sps30_state *state, u16 cmd, u8 *data, int size) > break; > case SPS30_READ_AUTO_CLEANING_PERIOD: > buf[0] = SPS30_AUTO_CLEANING_PERIOD >> 8; > - buf[1] = (u8)SPS30_AUTO_CLEANING_PERIOD; > + buf[1] = (u8)(SPS30_AUTO_CLEANING_PERIOD & 0xff); > /* fall through */ > case SPS30_READ_DATA_READY_FLAG: > case SPS30_READ_DATA: > -- > 2.23.0 > Thanks for catching this. Acked-by: Tomasz Duszynski