From mboxrd@z Thu Jan 1 00:00:00 1970 From: Stephen Warren Subject: Re: [PATCH v2] pinctrl: queue GPIO operations instead of defering Date: Mon, 19 Aug 2013 13:21:25 -0600 Message-ID: <52127035.7000909@wwwdotorg.org> References: <1376751410-14560-1-git-send-email-linus.walleij@linaro.org> Mime-Version: 1.0 Content-Type: text/plain; charset=ISO-8859-1 Content-Transfer-Encoding: 7bit Return-path: Received: from avon.wwwdotorg.org ([70.85.31.133]:50293 "EHLO avon.wwwdotorg.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1750938Ab3HSTV2 (ORCPT ); Mon, 19 Aug 2013 15:21:28 -0400 In-Reply-To: <1376751410-14560-1-git-send-email-linus.walleij@linaro.org> Sender: linux-next-owner@vger.kernel.org List-ID: To: Linus Walleij Cc: linux-kernel@vger.kernel.org, linux-arm-kernel@lists.infradead.org, Stephen Warren , Haojian Zhuang , Lars Poeschel , Javier Martinez Canillas , "linux-next@vger.kernel.org" , "linux-tegra@vger.kernel.org" On 08/17/2013 08:56 AM, Linus Walleij wrote: > We currently defer probing of the caller if a pinctrl GPIO > request or direction setting comes in before the range mapping > a certain GPIO to a certain pin controller is available. > > This can end up with a circular dependency: the GPIO driver > needs the pin controller to be ready and the pin controller > need the GPIO driver to be ready. This also happens if > pin controllers and GPIO controllers compiled as modules > are inserted in a certain order. > > To break this circular dependence, queue any GPIO > operations coming to the framework until the range is ready, > instead of deferring the probe of the caller. I just noticed that next-20130819 is failing on the Tegra114 Dalmore board because of this patch. The kernel log is below. Reverting this patch solves the problem > [ 12.427751] tegra114-pinctrl 70000868.pinmux: pin USB_VBUS_EN0 PN4 already requested by Tegra GPIOs:108; cannot claim for Tegra GPIOs:108 > [ 12.440320] tegra114-pinctrl 70000868.pinmux: pin-108 (Tegra GPIOs:108) status -22 > [ 12.447965] usb1_vbus: Failed to request enable GPIO108: -22 > [ 12.454306] reg-fixed-voltage 3.regulator: Failed to register regulator: -22 > [ 12.461508] reg-fixed-voltage: probe of 3.regulator failed with error -22 > [ 12.469659] tegra114-pinctrl 70000868.pinmux: pin SPDIF_IN PK6 already requested by Tegra GPIOs:86; cannot claim for Tegra GPIOs:86 > [ 12.481606] tegra114-pinctrl 70000868.pinmux: pin-86 (Tegra GPIOs:86) status -22 > [ 12.489052] usb2_vbus: Failed to request enable GPIO86: -22 > [ 12.495226] reg-fixed-voltage 4.regulator: Failed to register regulator: -22 > [ 12.502449] reg-fixed-voltage: probe of 4.regulator failed with error -22 > [ 12.510542] tegra114-pinctrl 70000868.pinmux: pin GMI_CLK PK1 already requested by Tegra GPIOs:81; cannot claim for Tegra GPIOs:81 > [ 12.522403] tegra114-pinctrl 70000868.pinmux: pin-81 (Tegra GPIOs:81) status -22 > [ 12.529896] vdd_hdmi_5v0: Failed to request enable GPIO81: -22 > [ 12.536281] reg-fixed-voltage 5.regulator: Failed to register regulator: -22 > [ 12.543465] reg-fixed-voltage: probe of 5.regulator failed with error -22 > [ 12.552509] vdd_cam_1v8_reg: 1800 mV > [ 12.558205] platform 7d008000.usb: Driver tegra-ehci requests probe deferral > [ 12.566600] platform 7d008000.usb-phy: Driver tegra-phy requests probe deferral > [ 12.577475] input: gpio-keys.2 as /devices/soc0/gpio-keys.2/input/input1 > [ 12.588329] platform 7d008000.usb: Driver tegra-ehci requests probe deferral > [ 12.596967] platform 7d008000.usb-phy: Driver tegra-phy requests probe deferral