From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id B8AE417F for ; Fri, 16 Apr 2021 12:52:03 +0000 (UTC) Received: by mail.kernel.org (Postfix) with ESMTPSA id BDDFD61107; Fri, 16 Apr 2021 12:52:02 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=linuxfoundation.org; s=korg; t=1618577523; bh=hwJ8s62yDIzmzZA0XYf+y6HvC+HhisQjYC0WgN+PGKw=; h=Date:From:To:Cc:Subject:References:In-Reply-To:From; b=G2m/SWVf8QKqq/Btcd4gPFqAbLsDT34XDLpJddTRhYn/QOuv+nKJIwxo3d7jjSkDU 1kAc68zdjhib0EwVoAVObGVbxEAG44nHvsCbKiduv7cvk1eaydVObPt+GcJUWUNW1B jgyNLtAyDs+vdJYNMEiRjh+obC8KOE9gUdTmYock= Date: Fri, 16 Apr 2021 14:51:59 +0200 From: Greg Kroah-Hartman To: Andy Shevchenko Cc: dri-devel@lists.freedesktop.org, linux-fbdev@vger.kernel.org, linux-staging@lists.linux.dev, linux-kernel@vger.kernel.org, Jan Sebastian =?iso-8859-1?Q?G=F6tte?= , Phil Reid , Nishad Kamdar Subject: Re: [PATCH v1 1/2] fbtft: Rectify GPIO handling Message-ID: References: <20210416123117.4993-1-andriy.shevchenko@linux.intel.com> X-Mailing-List: linux-staging@lists.linux.dev List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20210416123117.4993-1-andriy.shevchenko@linux.intel.com> On Fri, Apr 16, 2021 at 03:31:16PM +0300, Andy Shevchenko wrote: > The infamous commit c440eee1a7a1 ("Staging: fbtft: Switch to > the GPIO descriptor interface") broke GPIO handling completely. > It has already four commits to rectify and it seems not enough. > In order to fix the mess here we: > > 1) Set default to "inactive" for all requested pins > > 2) Fix CS, RD, and WR pins polarity since it's active low and > GPIO descriptor interface takes it into consideration from > the Device Tree or ACPI > > 3) Fix RESET pin polarity in the places missed by the commit > b918d1c27066 ("Staging: fbtft: Fix reset assertion when using gpio descriptor") > > 4) Consolidate chip activation (CS assert) under default > ->reset() callback > > To summarize the expectations about polarity for GPIOs: > > #RD Low > #WR Low > #CS Low > #RESET Low > DC or RS High > RW High > Data 0..15 High > > See also Adafruit learning course [1] for the example of the schematics. > > While at it, drop unneeded NULL checks, since GPIO API is tolerant to that. > At the end, update TODO to mark this job eventually done. > > [1]: https://learn.adafruit.com/adafruit-2-8-and-3-2-color-tft-touchscreen-breakout-v2/downloads Shouldn't this be broken up into "one patch per thing" from your list above? Feels like you did a lot of different things all in the same patch :( thanks, greg k-h