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 Received: from bombadil.infradead.org (bombadil.infradead.org [198.137.202.133]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.lore.kernel.org (Postfix) with ESMTPS id 56898C4321E for ; Thu, 1 Dec 2022 15:23:34 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=lists.infradead.org; s=bombadil.20210309; h=Sender: Content-Transfer-Encoding:Content-Type:MIME-Version:List-Subscribe:List-Help: List-Post:List-Archive:List-Unsubscribe:List-Id:Message-Id:Date:Subject:Cc:To :From:Reply-To:Content-ID:Content-Description:Resent-Date:Resent-From: Resent-Sender:Resent-To:Resent-Cc:Resent-Message-ID:In-Reply-To:References: List-Owner; bh=KrgghNPxs6tMyowi2e/+cqgWWmT4kMh67cvwDvexYFo=; b=GhNRR+ZVJgcZWp ZJbe3mvIsi2B21D2C3kdAofF6JYdC3bY84mBO/X0Zms2ebtFTgqLdLlRv4fpdjcdAr3/vPEva+xoD hud86Tpzqo/OZzKGKZxXMNWTD8O8yiiFin0CVEU9GLVH7QRt068NdgiqTCuEwlwNRYq7r/Tf6hlc8 QJXuNA6cp80hUA382vl1UVNk2l3dBxMljEa487swN1+8/Ww3qHK8cmHrNKAzGNnf3WnuhZoIVUA5R X7q0+z71HiaL5GN7vHUoKsQoP0UABd2YZb97RFLE/zicdI9h9stRHTAaLYbbUQXGaLOm2Fd3O6XQs 2WnB+vocIlIoOTqtv/7w==; Received: from localhost ([::1] helo=bombadil.infradead.org) by bombadil.infradead.org with esmtp (Exim 4.94.2 #2 (Red Hat Linux)) id 1p0lOa-008BZr-Od; Thu, 01 Dec 2022 15:22:40 +0000 Received: from foss.arm.com ([217.140.110.172]) by bombadil.infradead.org with esmtp (Exim 4.94.2 #2 (Red Hat Linux)) id 1p0lOX-008BYP-KJ for linux-arm-kernel@lists.infradead.org; Thu, 01 Dec 2022 15:22:39 +0000 Received: from usa-sjc-imap-foss1.foss.arm.com (unknown [10.121.207.14]) by usa-sjc-mx-foss1.foss.arm.com (Postfix) with ESMTP id 01A8AD6E; Thu, 1 Dec 2022 07:22:41 -0800 (PST) Received: from e110479.cambridge.arm.com (e110479.cambridge.arm.com [10.1.38.59]) by usa-sjc-imap-foss1.foss.arm.com (Postfix) with ESMTPSA id 342893F67D; Thu, 1 Dec 2022 07:22:32 -0800 (PST) From: Andre Przywara To: Thierry Reding , =?UTF-8?q?Uwe=20Kleine-K=C3=B6nig?= Cc: Chen-Yu Tsai , Jernej Skrabec , Samuel Holland , linux-pwm@vger.kernel.org, linux-arm-kernel@lists.infradead.org, linux-sunxi@lists.linux.dev Subject: [PATCH] pwm: sun4i: Propagate errors in .get_state() to the caller Date: Thu, 1 Dec 2022 15:22:23 +0000 Message-Id: <20221201152223.3133-1-andre.przywara@arm.com> X-Mailer: git-send-email 2.17.1 X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.8.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20221201_072237_734106_9921F092 X-CRM114-Status: GOOD ( 11.60 ) X-BeenThere: linux-arm-kernel@lists.infradead.org X-Mailman-Version: 2.1.34 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , MIME-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Sender: "linux-arm-kernel" Errors-To: linux-arm-kernel-bounces+linux-arm-kernel=archiver.kernel.org@lists.infradead.org .get_state() can return an error indication now. Make use of it to propagate an impossible prescaler encoding, should that have sneaked in somehow. Also check the return value of clk_get_rate(). That's unlikely to fail, but we use that in two divide operations down in the code, so let's avoid a divide-by-zero condition on the way. Signed-off-by: Andre Przywara --- Hi, this goes on top of Uwe's series to introduce and observe .get_state failures: https://lore.kernel.org/linux-pwm/20221130152148.2769768-12-u.kleine-koenig@pengutronix.de/T/#m9af39aa03bbd9bb7b31b3600f110c65ee0e8e70b Actually it only relies on patch 01/11 from that. Cheers, Andre drivers/pwm/pwm-sun4i.c | 4 +++- 1 file changed, 3 insertions(+), 1 deletion(-) diff --git a/drivers/pwm/pwm-sun4i.c b/drivers/pwm/pwm-sun4i.c index 37d75e252d4e..b973da73e9ab 100644 --- a/drivers/pwm/pwm-sun4i.c +++ b/drivers/pwm/pwm-sun4i.c @@ -118,6 +118,8 @@ static int sun4i_pwm_get_state(struct pwm_chip *chip, unsigned int prescaler; clk_rate = clk_get_rate(sun4i_pwm->clk); + if (!clk_rate) + return -EINVAL; val = sun4i_pwm_readl(sun4i_pwm, PWM_CTRL_REG); @@ -142,7 +144,7 @@ static int sun4i_pwm_get_state(struct pwm_chip *chip, prescaler = prescaler_table[PWM_REG_PRESCAL(val, pwm->hwpwm)]; if (prescaler == 0) - return 0; + return -EINVAL; if (val & BIT_CH(PWM_ACT_STATE, pwm->hwpwm)) state->polarity = PWM_POLARITY_NORMAL; -- 2.17.1 _______________________________________________ linux-arm-kernel mailing list linux-arm-kernel@lists.infradead.org http://lists.infradead.org/mailman/listinfo/linux-arm-kernel