From mboxrd@z Thu Jan 1 00:00:00 1970 From: Josh Cartwright Subject: Re: [PATCH] Input: pmic8xxx-pwrkey - Set sane default for debounce time Date: Mon, 31 Mar 2014 13:23:42 -0500 Message-ID: <20140331182342.GD28265@joshc.qualcomm.com> References: <1396289664-31893-1-git-send-email-sboyd@codeaurora.org> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Return-path: Content-Disposition: inline In-Reply-To: <1396289664-31893-1-git-send-email-sboyd@codeaurora.org> Sender: linux-kernel-owner@vger.kernel.org To: Stephen Boyd Cc: Dmitry Torokhov , linux-kernel@vger.kernel.org, linux-arm-msm@vger.kernel.org, linux-arm-kernel@lists.infradead.org, linux-input@vger.kernel.org, Arnd Bergmann List-Id: linux-input@vger.kernel.org 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; Should "debounce" even be optional? I'm wondering if we should just make it required... At the very least this default value should be documented in the DT binding. -- Qualcomm Innovation Center, Inc. is a member of Code Aurora Forum, hosted by The Linux Foundation