From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1752823Ab3ATDiK (ORCPT ); Sat, 19 Jan 2013 22:38:10 -0500 Received: from hqemgate04.nvidia.com ([216.228.121.35]:1406 "EHLO hqemgate04.nvidia.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752242Ab3ATDiI (ORCPT ); Sat, 19 Jan 2013 22:38:08 -0500 X-PGP-Universal: processed; by hqnvupgp06.nvidia.com on Sat, 19 Jan 2013 19:36:46 -0800 Message-ID: <50FB669C.3020704@nvidia.com> Date: Sun, 20 Jan 2013 11:38:04 +0800 From: Mark Zhang User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:17.0) Gecko/20130106 Thunderbird/17.0.2 MIME-Version: 1.0 To: Alexandre Courbot CC: Thierry Reding , Stephen Warren , "linux-fbdev@vger.kernel.org" , "linux-kernel@vger.kernel.org" , "linux-tegra@vger.kernel.org" , "gnurou@gmail.com" Subject: Re: [PATCH 0/3] pwm-backlight: add subdrivers & Tegra support References: <1358591420-7790-1-git-send-email-acourbot@nvidia.com> In-Reply-To: <1358591420-7790-1-git-send-email-acourbot@nvidia.com> Content-Type: text/plain; charset="ISO-8859-1" Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Yeah, thanks Alex. :) So this is a non power sequence version of backlight & panel enabling, isn't it? I remember we talked about this several days ago and you mentioned kernel guys want an ad-hoc version(power sequence logics inside driver, not in DT) and I believe this is it, right? I think finally I can enable Tegra30 cardhu's display after this patch merged. Mark On 01/19/2013 06:30 PM, Alexandre Courbot wrote: > This series introduces a way to use pwm-backlight hooks with platforms > that use the device tree through a subdriver system. It also adds support > for the Tegra-based Ventana board, adding the last missing block to enable > its panel. Support for other Tegra board can thus be easily added. > > I have something else in mind to properly support this (power > sequences), but this work relies on the GPIO subsystem redesign which will > take some time. The pwm-backlight subdrivers can do the job by the meantime. > > There are a few design points that might need to be discussed: > 1) Link order is important: subdrivers register themselves in their > module_init function, which must be called before pwm-backlight's probe. > This forbids linking subdrivers as separate modules from pwm-backlight. > 2) The subdriver's data is temporarily passed through the backlight > device's driver data. This should not hurt, but maybe there is a better way > to do this. > 3) Subdrivers must add themselves into pwm-backlight's own of_device_id > table. It would be cleaner to not have to list subdrivers into > pwm-backlight's main file, but I cannot think of a way to do otherwise. > > Suggestions for the 3 points listed above are very welcome - in any case, > I hope to make this converge into something mergeable quickly. > > Note that these patches are the last missing block to get a functional > panel on Tegra boards. Using 3.8rc4 and these patches, the internal panel > on Ventana is usable out-of-the-box. Yay. > > Alexandre Courbot (3): > pwm-backlight: add subdriver mechanism > tegra: pwm-backlight: add tegra pwm-bl driver > tegra: ventana: of: add host1x device to DT > > arch/arm/boot/dts/tegra20-ventana.dts | 29 +++++- > arch/arm/configs/tegra_defconfig | 1 + > drivers/video/backlight/Kconfig | 7 ++ > drivers/video/backlight/Makefile | 4 + > drivers/video/backlight/pwm_bl.c | 70 ++++++++++++++- > drivers/video/backlight/pwm_bl_tegra.c | 159 +++++++++++++++++++++++++++++++++ > include/linux/pwm_backlight.h | 15 ++++ > 7 files changed, 281 insertions(+), 4 deletions(-) > create mode 100644 drivers/video/backlight/pwm_bl_tegra.c >