From patchwork Tue Dec 20 10:27:03 2016 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Quentin Schulz X-Patchwork-Id: 9481373 Return-Path: Received: from mail.wl.linuxfoundation.org (pdx-wl-mail.web.codeaurora.org [172.30.200.125]) by pdx-korg-patchwork.web.codeaurora.org (Postfix) with ESMTP id D20CA601C0 for ; Tue, 20 Dec 2016 10:31:02 +0000 (UTC) Received: from mail.wl.linuxfoundation.org (localhost [127.0.0.1]) by mail.wl.linuxfoundation.org (Postfix) with ESMTP id C808228285 for ; Tue, 20 Dec 2016 10:31:02 +0000 (UTC) Received: by mail.wl.linuxfoundation.org (Postfix, from userid 486) id BB11D28407; Tue, 20 Dec 2016 10:31:02 +0000 (UTC) X-Spam-Checker-Version: SpamAssassin 3.3.1 (2010-03-16) on pdx-wl-mail.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-4.2 required=2.0 tests=BAYES_00, RCVD_IN_DNSWL_MED autolearn=unavailable version=3.3.1 Received: from bombadil.infradead.org (bombadil.infradead.org [198.137.202.9]) (using TLSv1.2 with cipher AES128-GCM-SHA256 (128/128 bits)) (No client certificate requested) by mail.wl.linuxfoundation.org (Postfix) with ESMTPS id 7A68728285 for ; Tue, 20 Dec 2016 10:31:02 +0000 (UTC) Received: from localhost ([127.0.0.1] helo=bombadil.infradead.org) by bombadil.infradead.org with esmtp (Exim 4.85_2 #1 (Red Hat Linux)) id 1cJHfX-0006Yn-Cg; Tue, 20 Dec 2016 10:29:15 +0000 Received: from mail.free-electrons.com ([62.4.15.54]) by bombadil.infradead.org with esmtp (Exim 4.85_2 #1 (Red Hat Linux)) id 1cJHew-0005pZ-KU for linux-arm-kernel@lists.infradead.org; Tue, 20 Dec 2016 10:28:41 +0000 Received: by mail.free-electrons.com (Postfix, from userid 110) id 620A420C07; Tue, 20 Dec 2016 11:28:18 +0100 (CET) Received: from qschulz.home (LStLambert-657-1-97-87.w90-63.abo.wanadoo.fr [90.63.216.87]) by mail.free-electrons.com (Postfix) with ESMTPSA id 01D0D20975; Tue, 20 Dec 2016 11:28:07 +0100 (CET) From: Quentin Schulz To: jic23@kernel.org, knaack.h@gmx.de, lars@metafoo.de, pmeerw@pmeerw.net, robh+dt@kernel.org, mark.rutland@arm.com, maxime.ripard@free-electrons.com, wens@csie.org, lee.jones@linaro.org, linux@armlinux.org.uk, stefan.mavrodiev@gmail.com Subject: [PATCH 1/7] Documentation: DT: bindings: iio: adc: add documentation for Allwinner SoCs' GPADC driver Date: Tue, 20 Dec 2016 11:27:03 +0100 Message-Id: <20161220102709.9504-2-quentin.schulz@free-electrons.com> X-Mailer: git-send-email 2.9.3 In-Reply-To: <20161220102709.9504-1-quentin.schulz@free-electrons.com> References: <20161220102709.9504-1-quentin.schulz@free-electrons.com> X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.8.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20161220_022839_110066_27F880AB X-CRM114-Status: GOOD ( 16.04 ) X-BeenThere: linux-arm-kernel@lists.infradead.org X-Mailman-Version: 2.1.20 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Cc: thomas.petazzoni@free-electrons.com, devicetree@vger.kernel.org, linux-iio@vger.kernel.org, linux-kernel@vger.kernel.org, Quentin Schulz , linux-arm-kernel@lists.infradead.org MIME-Version: 1.0 Sender: "linux-arm-kernel" Errors-To: linux-arm-kernel-bounces+patchwork-linux-arm=patchwork.kernel.org@lists.infradead.org X-Virus-Scanned: ClamAV using ClamSMTP The Allwinner SoCs all have an ADC that can also act as a thermal sensor and sometimes as a touchscreen controller. If there is a touchscreen controller, the first four channels can be used either for the ADC or the touchscreen and the fifth channel is used for the thermal sensor. If there is not a touchscreen controller, the one and only channel is used for the thermal sensor. This patch adds the documentation for the driver of the Allwinner SoCs' GPADC. Signed-off-by: Quentin Schulz --- .../bindings/iio/adc/sun4i-gpadc-iio.txt | 57 ++++++++++++++++++++++ 1 file changed, 57 insertions(+) create mode 100644 Documentation/devicetree/bindings/iio/adc/sun4i-gpadc-iio.txt diff --git a/Documentation/devicetree/bindings/iio/adc/sun4i-gpadc-iio.txt b/Documentation/devicetree/bindings/iio/adc/sun4i-gpadc-iio.txt new file mode 100644 index 0000000..aab768d --- /dev/null +++ b/Documentation/devicetree/bindings/iio/adc/sun4i-gpadc-iio.txt @@ -0,0 +1,57 @@ +Allwinner SoCs' GPADC Device Tree bindings +------------------------------------------ + +The Allwinner SoCs all have an ADC that can also act as a thermal sensor and +sometimes as a touchscreen controller. If there is a touchscreen controller, the +first four channels can be used either for the ADC or the touchscreen and the +fifth channel is used for the thermal sensor. +If there is not a touchscreen controller, the one and only channel is used for +the thermal sensor. + +Currently, the touchscreen controller does not have a driver using this ADC +driver. The touchscreen controller is currently driven only by +input/touchscreen/sun4i-ts.c which is absolutely incompatible with this driver. + +The Allwinner A10, A13 and A31 SoCs already have a DT binding for the +aforementioned input driver, thus an MFD driver matches the existing DT binding +(mfd/sun4i-gpadc.c) and replaces the input driver. No DT binding is required for +these SoCs' ADC, everything is handled by the MFD which is matching the existing +DT binding for input/touchscreen/sun4i-ts.c. + +The Allwinner A33 GPADC only have a thermal sensor and have a proper DT binding +for this driver unlike the previously mentioned SoCs. + +Required properties: + - compatible: "allwinner,sun8i-a33-gpadc-iio" + +Optional properties: +(for use with thermal framework for CPU thermal throttling for example, and/or + IIO consumers) + - #thermal-sensor-cells = <0>; (see +Documentation/devicetree/bindings/thermal/thermal.txt) + - #io-channel-cells = <0>; (see +Documentation/devicetree/bindings/iio/iio-bindings.txt) + +Example: + +thermal-zones { + cpu_thermal { + thermal-sensors = <&rtp>; + [...] + }; +}; + +soc@01c00000 { + [...] + rtp: rtp@01c25000 { + compatible = "allwinner,sun8i-a33-gpadc-iio"; + reg = <0x01c25000 0x100>; + #thermal-sensor-cells = <0>; + #io-channel-cells = <0>; + }; +} + +iio_hwmon { + compatible = "iio-hwmon"; + io-channels = <&rtp>; +};