From mboxrd@z Thu Jan 1 00:00:00 1970 From: Vladimir Zapolskiy Date: Fri, 30 Dec 2016 09:24:50 +0000 Subject: Re: [PATCH 4/4] video: ARM CLCD: add support of an optional GPIO to enable panel Message-Id: <7ac1d3ba-394c-f7de-268c-59a63eb27e8c@mleia.com> List-Id: References: <20161221032717.13154-1-vz@mleia.com> <20161221032717.13154-5-vz@mleia.com> In-Reply-To: MIME-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit To: linux-arm-kernel@lists.infradead.org On 12/30/2016 10:20 AM, Linus Walleij wrote: > On Wed, Dec 21, 2016 at 4:27 AM, Vladimir Zapolskiy wrote: > >> The change adds handling of "enable-gpios" property of panel-dpi device >> node used with an ARM CLCD controller, note that the property already has >> a description in display/panel/panel-dpi.txt documentation and it founds >> practical usage while describing some panel devices connected to other >> types of display controllers. >> >> Signed-off-by: Vladimir Zapolskiy > > So as you may have seen I already handle a RESET GPIO in the > Nomadik TPG110 panel subddriver in > drivers/video/fbdev/amba-clcd-nomadik.c > > So is this all your panel needs? I need "enable-gpios" property to define a GPIO, which literally enables (powers up) a panel as a separate attached PCB. To some extend "enable-gpios" property can be replaced by "power" property with a phandle to a GPIO voltage regulator. You may look at drivers/gpu/drm/panel/panel-simple.c, both "enable-gpios" and "power" properties are defined for simple panels. > > I guess it is OK for simple panels. > -- With best wishes, Vladimir