From mboxrd@z Thu Jan 1 00:00:00 1970 From: Rob Herring Subject: Re: [PATCH v2] pinctrl: at91-pio4: add support for drive strength Date: Thu, 5 Jul 2018 12:04:57 -0600 Message-ID: <20180705180457.GA5809@rob-hp-laptop> References: <20180629081533.31885-1-ludovic.desroches@microchip.com> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Return-path: Content-Disposition: inline In-Reply-To: <20180629081533.31885-1-ludovic.desroches@microchip.com> Sender: linux-kernel-owner@vger.kernel.org To: Ludovic Desroches Cc: linux-gpio@vger.kernel.org, devicetree@vger.kernel.org, linux-arm-kernel@lists.infradead.org, linux-kernel@vger.kernel.org, linus.walleij@linaro.org, nicolas.ferre@microchip.com, alexandre.belloni@bootlin.com List-Id: devicetree@vger.kernel.org On Fri, Jun 29, 2018 at 10:15:33AM +0200, Ludovic Desroches wrote: > Add support for the drive strength configuration. Usually, this value is > expressed in mA. Since the numeric value depends on VDDIOP voltage, a > value we can't retrieve at runtime, the controller uses low, medium and > high to define the drive strength. > > The PIO controller accepts two values for the low drive configuration: 0 > and 1. Most of the time, we don't care about the drive strength. So we > keep the default value which is 0. The drive strength is advertised > through the sysfs only when it has been explicitly set in the device > tree i.e. if its value is different from 0. > > Signed-off-by: Ludovic Desroches > --- > > Changes: > - v2: use atmel,drive-strength property instead of drive-strengh one > since it is not expressend in mA and there is no way to retrieve this > value at runtime. > - v1: https://www.spinics.net/lists/linux-gpio/msg27789.html > > .../bindings/pinctrl/atmel,at91-pio4-pinctrl.txt | 3 ++ > drivers/pinctrl/pinctrl-at91-pio4.c | 42 ++++++++++++++++++++++ > include/dt-bindings/pinctrl/at91.h | 4 +++ > 3 files changed, 49 insertions(+) For the DT parts, Acked-by: Rob Herring