From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-8.2 required=3.0 tests=HEADER_FROM_DIFFERENT_DOMAINS, INCLUDES_PATCH,MAILING_LIST_MULTI,SIGNED_OFF_BY,SPF_HELO_NONE,SPF_PASS, URIBL_BLOCKED,USER_AGENT_SANE_1 autolearn=ham autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id 1128EC2BA2B for ; Thu, 9 Apr 2020 14:46:20 +0000 (UTC) Received: from gabe.freedesktop.org (gabe.freedesktop.org [131.252.210.177]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPS id D63FE2051A for ; Thu, 9 Apr 2020 14:46:19 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org D63FE2051A Authentication-Results: mail.kernel.org; dmarc=none (p=none dis=none) header.from=ravnborg.org Authentication-Results: mail.kernel.org; spf=none smtp.mailfrom=dri-devel-bounces@lists.freedesktop.org Received: from gabe.freedesktop.org (localhost [127.0.0.1]) by gabe.freedesktop.org (Postfix) with ESMTP id 3BD3D883C5; Thu, 9 Apr 2020 14:46:19 +0000 (UTC) Received: from asavdk3.altibox.net (asavdk3.altibox.net [109.247.116.14]) by gabe.freedesktop.org (Postfix) with ESMTPS id 2A90D6E226 for ; Thu, 9 Apr 2020 14:46:17 +0000 (UTC) Received: from ravnborg.org (unknown [158.248.194.18]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by asavdk3.altibox.net (Postfix) with ESMTPS id 7A1A820029; Thu, 9 Apr 2020 16:46:14 +0200 (CEST) Date: Thu, 9 Apr 2020 16:46:13 +0200 From: Sam Ravnborg To: Emil Velikov Subject: Re: [PATCH v1 2/3] drm/panel: update backlight handling for samsung-s6e63j0x03 Message-ID: <20200409144613.GA5396@ravnborg.org> References: <20200409115239.5149-1-sam@ravnborg.org> <20200409115239.5149-3-sam@ravnborg.org> MIME-Version: 1.0 Content-Disposition: inline In-Reply-To: User-Agent: Mutt/1.10.1 (2018-07-13) X-CMAE-Score: 0 X-CMAE-Analysis: v=2.3 cv=eMA9ckh1 c=1 sm=1 tr=0 a=UWs3HLbX/2nnQ3s7vZ42gw==:117 a=UWs3HLbX/2nnQ3s7vZ42gw==:17 a=jpOVt7BSZ2e4Z31A5e1TngXxSK0=:19 a=8nJEP1OIZ-IA:10 a=7gkXJVJtAAAA:8 a=hD80L64hAAAA:8 a=pGLkceISAAAA:8 a=BIUAI-DsY62N6ERaLFUA:9 a=wPNLvfGTeEIA:10 a=E9Po1WZjFZOl8hwRPBS3:22 X-BeenThere: dri-devel@lists.freedesktop.org X-Mailman-Version: 2.1.29 Precedence: list List-Id: Direct Rendering Infrastructure - Development List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Cc: Joonas =?iso-8859-1?Q?Kylm=E4l=E4?= , ML dri-devel , Andrzej Hajda , Thierry Reding , Hyungwon Hwang , Hoegeun Kwon , =?utf-8?B?UGF3ZcWC?= Chmiel Content-Type: text/plain; charset="iso-8859-1" Content-Transfer-Encoding: quoted-printable Errors-To: dri-devel-bounces@lists.freedesktop.org Sender: "dri-devel" Hi Emil. Thanks for your feedback! On Thu, Apr 09, 2020 at 03:13:28PM +0100, Emil Velikov wrote: > On Thu, 9 Apr 2020 at 12:53, Sam Ravnborg wrote: > > > > The samsung-s6e63j0x03 had a local way to handle backlight. > > > > Update the driver to use a devm_ based register function > > and utilize drm_panel backlight support. The changes results > > in a simpler driver with the same functionality. > > > > Signed-off-by: Sam Ravnborg > > Cc: Joonas Kylm=E4l=E4 > > Cc: Andrzej Hajda > > Cc: Thierry Reding > > Cc: Inki Dae > > Cc: Hyungwon Hwang > > Cc: Hoegeun Kwon > > --- > > .../gpu/drm/panel/panel-samsung-s6e63j0x03.c | 55 ++++++++++--------- > > 1 file changed, 29 insertions(+), 26 deletions(-) > > > > diff --git a/drivers/gpu/drm/panel/panel-samsung-s6e63j0x03.c b/drivers= /gpu/drm/panel/panel-samsung-s6e63j0x03.c > > index a3570e0a90a8..2c035f87e3f0 100644 > > --- a/drivers/gpu/drm/panel/panel-samsung-s6e63j0x03.c > > +++ b/drivers/gpu/drm/panel/panel-samsung-s6e63j0x03.c > > @@ -36,7 +36,6 @@ > > struct s6e63j0x03 { > > struct device *dev; > > struct drm_panel panel; > > - struct backlight_device *bl_dev; > > > > struct regulator_bulk_data supplies[2]; > > struct gpio_desc *reset_gpio; > > @@ -184,7 +183,7 @@ static unsigned int s6e63j0x03_get_brightness_index= (unsigned int brightness) > > static int s6e63j0x03_update_gamma(struct s6e63j0x03 *ctx, > > unsigned int brightness) > > { > > - struct backlight_device *bl_dev =3D ctx->bl_dev; > > + struct backlight_device *bl_dev =3D ctx->panel.backlight; > > unsigned int index =3D s6e63j0x03_get_brightness_index(brightne= ss); > > int ret; > > > > @@ -217,6 +216,30 @@ static const struct backlight_ops s6e63j0x03_bl_op= s =3D { > > .update_status =3D s6e63j0x03_set_brightness, > > }; > > > > +static int s6e63j0x03_backlight_register(struct s6e63j0x03 *ctx) > > +{ > > + struct backlight_properties props =3D { > Pretty sure we can (should really) make the props const. Thanks, will fix either in v2 or when I apply. > = > Quick grep through drm, shows that there're other offenders, so might > as well do that in separate series. > Seems like other panels could follow suite, with later series of course. > = > Back on topic, it's not immediately obvious why the FB_BLANK_* > handling is safe to remove. Please add small mention in the commit log > mentioning why. Maybe because it is not so? Lets take a closer look. backlight_enable() and backlight_disable() are called from drm_panel - because drm_panel->backlight is assigned. drm_panel_prepare: OLD: ctx->bl_dev->props.power =3D FB_BLANK_NORMAL; NEW: drm_panel_enable: OLD: ctx->bl_dev->props.power =3D FB_BLANK_UNBLANK; NEW: backlight_enable() =3D> = bd->props.power =3D FB_BLANK_UNBLANK; bd->props.fb_blank =3D FB_BLANK_UNBLANK; bd->props.state &=3D ~BL_CORE_FBBLANK; drm_panel_disable: OLD: ctx->bl_dev->props.power =3D FB_BLANK_NORMAL; NEW: backlight_disable() =3D> bd->props.power =3D FB_BLANK_POWERDOWN; bd->props.fb_blank =3D FB_BLANK_POWERDOWN; bd->props.state |=3D BL_CORE_FBBLANK; drm_panel_unprepare: OLD: ctx->bl_dev->props.power =3D FB_BLANK_POWERDOWN; NEW: So old and new code are not exactly the same. But with my (limited) backlight understanding this should work as expected - and it works for many other drivers. So if this does not work, then we should look at the backlight handling and not do workarounds in the driver. I will summarize the above in the individual changelogs. Sam > = > -Emil _______________________________________________ dri-devel mailing list dri-devel@lists.freedesktop.org https://lists.freedesktop.org/mailman/listinfo/dri-devel