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=-7.1 required=3.0 tests=DKIM_SIGNED,DKIM_VALID, DKIM_VALID_AU,HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_PATCH,MAILING_LIST_MULTI, SIGNED_OFF_BY,SPF_PASS,URIBL_BLOCKED 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 BA282C43444 for ; Sun, 16 Dec 2018 07:18:31 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 88DAA206C2 for ; Sun, 16 Dec 2018 07:18:31 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (1024-bit key) header.d=ideasonboard.com header.i=@ideasonboard.com header.b="ua90CWZW" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1729804AbeLPHSa (ORCPT ); Sun, 16 Dec 2018 02:18:30 -0500 Received: from perceval.ideasonboard.com ([213.167.242.64]:45918 "EHLO perceval.ideasonboard.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1729732AbeLPHSa (ORCPT ); Sun, 16 Dec 2018 02:18:30 -0500 Received: from avalon.localnet (dfj612ybrt5fhg77mgycy-3.rev.dnainternet.fi [IPv6:2001:14ba:21f5:5b00:2e86:4862:ef6a:2804]) by perceval.ideasonboard.com (Postfix) with ESMTPSA id DFAD159; Sun, 16 Dec 2018 08:18:27 +0100 (CET) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=ideasonboard.com; s=mail; t=1544944708; bh=qoGwzlaskFJNCbfPgNBGL4Dln3f/91qSpPx48HuywhE=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=ua90CWZWdoJLCxITBI91/TRhy2b/TM5x7kieiQOg9Vbx7fGTvSRFI9J2hQetdiSS9 v4Xl/0REENMvhUJeCbKEkR4Sl5yOPYOTPjRSrD376/tSD+7ezvW7yvEpywWrhmskSb DwZ4hKvr2UGS5/vtp5QvOjJiP27MXLgkgjniMW6M= From: Laurent Pinchart To: Marek Vasut Cc: linux-clk@vger.kernel.org, linux-renesas-soc@vger.kernel.org, Marek Vasut , Alexey Firago , Stephen Boyd Subject: Re: [PATCH] clk: vc5: Abort clock configuration without upstream clock Date: Sun, 16 Dec 2018 09:19:16 +0200 Message-ID: <13438812.kSL9ZioSIq@avalon> Organization: Ideas on Board Oy In-Reply-To: <20181215005519.3695-1-marek.vasut+renesas@gmail.com> References: <20181215005519.3695-1-marek.vasut+renesas@gmail.com> MIME-Version: 1.0 Content-Transfer-Encoding: 7Bit Content-Type: text/plain; charset="us-ascii" Sender: linux-clk-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-clk@vger.kernel.org Hi Marek, Thank you for the patch. On Saturday, 15 December 2018 02:55:19 EET Marek Vasut wrote: > In case the upstream clock are not set, which can happen in case the > VC5 has no valid upstream clock, the $src variable is used uninited > by regmap_update_bits(). Check for this condition and return -EINVAL > in such case. Note that the probe() function will fail in this case, so vc5_mux_set_parent() won't be reached. > Note that in case the VC5 has no valid upstream clock, the VC5 can > not operate correctly. That is a hardware property of the VC5. The > internal oscilator present in some VC5 models is also considered > upstream clock. > > Signed-off-by: Marek Vasut > Cc: Alexey Firago > Cc: Laurent Pinchart > Cc: Stephen Boyd > Cc: linux-renesas-soc@vger.kernel.org > --- > NOTE: This is an updated version of: > https://patchwork.kernel.org/patch/10731699/ > --- > drivers/clk/clk-versaclock5.c | 4 +++- > 1 file changed, 3 insertions(+), 1 deletion(-) > > diff --git a/drivers/clk/clk-versaclock5.c b/drivers/clk/clk-versaclock5.c > index 5b393e711e94..b10801506518 100644 > --- a/drivers/clk/clk-versaclock5.c > +++ b/drivers/clk/clk-versaclock5.c > @@ -262,8 +262,10 @@ static int vc5_mux_set_parent(struct clk_hw *hw, u8 > index) > > if (vc5->clk_mux_ins == VC5_MUX_IN_XIN) > src = VC5_PRIM_SRC_SHDN_EN_XTAL; > - if (vc5->clk_mux_ins == VC5_MUX_IN_CLKIN) > + else if (vc5->clk_mux_ins == VC5_MUX_IN_CLKIN) > src = VC5_PRIM_SRC_SHDN_EN_CLKIN; > + else > + return -EINVAL; > } I'd rather go for Stephen's approach if the goal is just to silence a warning for a condition that can't happen in practice. > return regmap_update_bits(vc5->regmap, VC5_PRIM_SRC_SHDN, mask, src); -- Regards, Laurent Pinchart