From mboxrd@z Thu Jan 1 00:00:00 1970 From: Krzysztof Kozlowski Subject: Re: [PATCH 6/8] regulator: max77686: Add external GPIO control Date: Wed, 29 Oct 2014 11:42:42 +0100 Message-ID: <1414579362.18868.11.camel@AMDC1943> References: <1414422226-10948-1-git-send-email-k.kozlowski@samsung.com> <1414422226-10948-7-git-send-email-k.kozlowski@samsung.com> <544EA4FA.6040704@collabora.co.uk> <1414486356.24949.19.camel@AMDC1943> <1414498308.24949.32.camel@AMDC1943> Mime-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 7bit Return-path: In-reply-to: <1414498308.24949.32.camel@AMDC1943> Sender: linux-kernel-owner@vger.kernel.org To: Javier Martinez Canillas Cc: Samuel Ortiz , Lee Jones , Liam Girdwood , Mark Brown , linux-kernel@vger.kernel.org, Ben Dooks , Kukjin Kim , Russell King , linux-arm-kernel@lists.infradead.org, linux-samsung-soc@vger.kernel.org, devicetree@vger.kernel.org, Kyungmin Park , Marek Szyprowski , Bartlomiej Zolnierkiewicz , Chanwoo Choi List-Id: devicetree@vger.kernel.org On wto, 2014-10-28 at 13:11 +0100, Krzysztof Kozlowski wrote: > On wto, 2014-10-28 at 09:52 +0100, Krzysztof Kozlowski wrote: > > On pon, 2014-10-27 at 21:03 +0100, Javier Martinez Canillas wrote: > > > Hello Krzysztof, > > > > > > On 10/27/2014 04:03 PM, Krzysztof Kozlowski wrote: > > > > @@ -85,6 +91,9 @@ struct max77686_data { > > > > struct max77686_regulator_data *regulators; > > > > int num_regulators; > > > > > > > > + /* Array of size num_regulators with GPIOs for external control. */ > > > > + int *ext_control_gpio; > > > > + > > > > > > The integer-based GPIO API is deprecated in favor of the descriptor-based GPIO > > > interface (Documentation/gpio/consumer.txt). Could you please use the later? > > > > Sure, I can. Please have in mind that regulator core still accepts old > > GPIO so I will have to use desc_to_gpio(). That should work... and > > should be future-ready. > > It seems I was too hasty... I think usage of the new gpiod API implies > completely different bindings. > > The gpiod_get() gets GPIO from a device level, not from given sub-node > pointer. This means that you cannot have DTS like this: > ldo21_reg: ldo21 { > regulator-compatible = "LDO21"; > regulator-name = "VTF_2.8V"; > regulator-min-microvolt = <2800000>; > regulator-max-microvolt = <2800000>; > ec-gpio = <&gpy2 0 0>; > }; > > ldo22_reg: ldo22 { > regulator-compatible = "LDO22"; > regulator-name = "VMEM_VDD_2.8V"; > regulator-min-microvolt = <2800000>; > regulator-max-microvolt = <2800000>; > ec-gpio = <&gpk0 2 0>; > }; > > > I could put GPIOs in device node: > > max77686_pmic@09 { > compatible = "maxim,max77686"; > interrupt-parent = <&gpx0>; > interrupts = <7 0>; > reg = <0x09>; > #clock-cells = <1>; > ldo21-gpio = <&gpy2 0 0>; > ldo22-gpio = <&gpk0 2 0>; > > ldo21_reg: ldo21 { > regulator-compatible = "LDO21"; > regulator-name = "VTF_2.8V"; > regulator-min-microvolt = <2800000>; > regulator-max-microvolt = <2800000>; > }; > > ldo22_reg: ldo22 { > regulator-compatible = "LDO22"; > regulator-name = "VMEM_VDD_2.8V"; > regulator-min-microvolt = <2800000>; > regulator-max-microvolt = <2800000>; > }; > > This would work but I don't like it. The properties of a regulator are > above the node configuring that regulator. > > Any ideas? > Continuing talking to myself... I found another problem - GPIO cannot be requested more than once (-EBUSY). In case of this driver (and board: Trats2) one GPIO is connected to regulators. The legacy GPIO API and regulator core handle this. With new GPIO API I would have to implement some additional steps in such case... So there are 2 issues: 1. Cannot put GPIO property in regulator node. 2. Cannot request some GPIO more than once. I'm going back to legacy API for now. Best regards, Krzysztof