From mboxrd@z Thu Jan 1 00:00:00 1970 From: Stephen Boyd Subject: Re: [PATCH] Input: pmic8xxx-pwrkey - Set sane default for debounce time Date: Mon, 31 Mar 2014 11:29:27 -0700 Message-ID: <5339B407.1050308@codeaurora.org> References: <1396289664-31893-1-git-send-email-sboyd@codeaurora.org> <20140331182315.GA9198@core.coreip.homeip.net> Mime-Version: 1.0 Content-Type: text/plain; charset=ISO-8859-1 Content-Transfer-Encoding: 7bit Return-path: Received: from smtp.codeaurora.org ([198.145.11.231]:40959 "EHLO smtp.codeaurora.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1753176AbaCaS33 (ORCPT ); Mon, 31 Mar 2014 14:29:29 -0400 In-Reply-To: <20140331182315.GA9198@core.coreip.homeip.net> Sender: linux-input-owner@vger.kernel.org List-Id: linux-input@vger.kernel.org To: Dmitry Torokhov Cc: linux-kernel@vger.kernel.org, linux-arm-msm@vger.kernel.org, linux-arm-kernel@lists.infradead.org, linux-input@vger.kernel.org, Arnd Bergmann On 03/31/14 11:23, Dmitry Torokhov wrote: > On Mon, Mar 31, 2014 at 11:14:24AM -0700, Stephen Boyd wrote: >> If the debounce time is 0 our usage of ilog2() later on in this >> driver will cause undefined behavior. If CONFIG_OF=n this fact is >> evident to the compiler, and it emits a call to ____ilog2_NaN() >> which doesn't exist. Fix this by setting a sane default for >> debounce. >> >> Reported-by: Arnd Bergmann >> Signed-off-by: Stephen Boyd >> --- >> drivers/input/misc/pmic8xxx-pwrkey.c | 2 +- >> 1 file changed, 1 insertion(+), 1 deletion(-) >> >> diff --git a/drivers/input/misc/pmic8xxx-pwrkey.c b/drivers/input/misc/pmic8xxx-pwrkey.c >> index 1cb8fda7a166..27add04676e1 100644 >> --- a/drivers/input/misc/pmic8xxx-pwrkey.c >> +++ b/drivers/input/misc/pmic8xxx-pwrkey.c >> @@ -92,7 +92,7 @@ static int pmic8xxx_pwrkey_probe(struct platform_device *pdev) >> bool pull_up; >> >> if (of_property_read_u32(pdev->dev.of_node, "debounce", &kpd_delay)) >> - kpd_delay = 0; >> + kpd_delay = 15625; > What if somebody supplied 0 via DT? Can we check and return -EINVAL? Sure. Here's a v2. -----8<------ From: Stephen Boyd Subject: [PATCH v2] Input: pmic8xxx-pwrkey - Set sane default for debounce time If the debounce time is 0 our usage of ilog2() later on in this driver will cause undefined behavior. If CONFIG_OF=n this fact is evident to the compiler, and it emits a call to ____ilog2_NaN() which doesn't exist. Fix this by setting a sane default for debounce and failing to probe if debounce is 0 in the DT. Reported-by: Arnd Bergmann Signed-off-by: Stephen Boyd --- drivers/input/misc/pmic8xxx-pwrkey.c | 4 ++-- 1 file changed, 2 insertions(+), 2 deletions(-) diff --git a/drivers/input/misc/pmic8xxx-pwrkey.c b/drivers/input/misc/pmic8xxx-pwrkey.c index 1cb8fda7a166..3fb161902cc6 100644 --- a/drivers/input/misc/pmic8xxx-pwrkey.c +++ b/drivers/input/misc/pmic8xxx-pwrkey.c @@ -92,11 +92,11 @@ static int pmic8xxx_pwrkey_probe(struct platform_device *pdev) bool pull_up; if (of_property_read_u32(pdev->dev.of_node, "debounce", &kpd_delay)) - kpd_delay = 0; + kpd_delay = 15625; pull_up = of_property_read_bool(pdev->dev.of_node, "pull-up"); - if (kpd_delay > 62500) { + if (kpd_delay > 62500 || kpd_delay == 0) { dev_err(&pdev->dev, "invalid power key trigger delay\n"); return -EINVAL; } -- Qualcomm Innovation Center, Inc. is a member of Code Aurora Forum, hosted by The Linux Foundation