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=-13.3 required=3.0 tests=BAYES_00,DKIMWL_WL_HIGH, DKIM_SIGNED,DKIM_VALID,DKIM_VALID_AU,HEADER_FROM_DIFFERENT_DOMAINS, INCLUDES_CR_TRAILER,INCLUDES_PATCH,MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS, UNWANTED_LANGUAGE_BODY autolearn=unavailable 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 33741C4708F for ; Tue, 1 Jun 2021 22:20:36 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 184D1613C1 for ; Tue, 1 Jun 2021 22:20:36 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S235006AbhFAWWP (ORCPT ); Tue, 1 Jun 2021 18:22:15 -0400 Received: from us-smtp-delivery-124.mimecast.com ([216.205.24.124]:47824 "EHLO us-smtp-delivery-124.mimecast.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S234766AbhFAWWP (ORCPT ); Tue, 1 Jun 2021 18:22:15 -0400 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=redhat.com; s=mimecast20190719; t=1622586032; h=from:from:reply-to:subject:subject:date:date:message-id:message-id: to:to:cc:cc:mime-version:mime-version:content-type:content-type: content-transfer-encoding:content-transfer-encoding: in-reply-to:in-reply-to:references:references; bh=zNZ1OHz+pgy9lSJZpnW7dTMVx/2d5p7wzElxmNic5mo=; b=Qj+o3RsIYjMTdQc6zqRwgtrtY/G0Qtqrx2pEcH2zFqnSRFsHQEKH+8SCQFmUq4i+LmlLyP x+urX1ffhrB2hrKkzZsu5AQGr834qj2QRwr1ODKSPXEBDNXFaKQ3NiEWJ1YqNoVmBNcuNx PkalbNUgl1+kvJEhSpZ6ZKMnvhN5aqA= Received: from mail-qv1-f70.google.com (mail-qv1-f70.google.com [209.85.219.70]) (Using TLS) by relay.mimecast.com with ESMTP id us-mta-557-gP3QMzi3MZKNAp2X1-Uy7Q-1; Tue, 01 Jun 2021 18:20:31 -0400 X-MC-Unique: gP3QMzi3MZKNAp2X1-Uy7Q-1 Received: by mail-qv1-f70.google.com with SMTP id v19-20020a0ce1d30000b02902187ed4452eso334595qvl.6 for ; Tue, 01 Jun 2021 15:20:31 -0700 (PDT) X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:message-id:subject:from:to:cc:date:in-reply-to :references:organization:user-agent:mime-version :content-transfer-encoding; bh=zNZ1OHz+pgy9lSJZpnW7dTMVx/2d5p7wzElxmNic5mo=; b=Nmtw2AhcDcUwZkplS/07T62yayBlYWriL9cCSQ0PBDxuuLt0fcLgI+gpMnE4iTn+IN SVKolrTWBwvV0Q+dI702LaC1L3TC5s5zGrUaIlvLo7WcwrISFkUqEz06eF8SwZXZ4Xk5 uX6CKro38kwIXjLBOvi10CEV8hFmdscvSzxlTCCnKy4WtlEZCkCwLVyMMrIZhRQI4sIq hDQ2btjk2U/eIEn6unf/g5l/C40ILpD4+6o46enVnMIIZJWGamyWNIx+pfFAuR/Q2sbS mWCO1tBCpCAbm5B7OAou1kjty96MIl8C0qtHqw0Aoiv018yXkhHCbVeYEi7wp0ajWR/P smig== X-Gm-Message-State: AOAM53061FjVNE4XWE1a1+/kg59MWLRY42uJF16htzNsQ3e0mJABPcpS BWYFB1YvbtGahmaPR1VoHS7l5prkFF8IDc+0uJq4Z5bqhy0NMdfAHmxY5QLevmtLsY6cKz/TPGf FQRXKTN8jeUZhx5h4fif5CUmabQ== X-Received: by 2002:a05:620a:4007:: with SMTP id h7mr23810767qko.257.1622586031306; Tue, 01 Jun 2021 15:20:31 -0700 (PDT) X-Google-Smtp-Source: ABdhPJwYa1qLyQ3m0UnCgsn0rF7qsVaI/mfTUhKZHlBTOPeAih4/7wa4I1RxpaoBnF8u9RQgUPIEog== X-Received: by 2002:a05:620a:4007:: with SMTP id h7mr23810728qko.257.1622586031051; Tue, 01 Jun 2021 15:20:31 -0700 (PDT) Received: from Ruby.lyude.net (pool-108-49-102-102.bstnma.fios.verizon.net. [108.49.102.102]) by smtp.gmail.com with ESMTPSA id f130sm161456qke.37.2021.06.01.15.20.29 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Tue, 01 Jun 2021 15:20:30 -0700 (PDT) Message-ID: <4df7dcddd5aca799361642ea91c37fa94e8a4fef.camel@redhat.com> Subject: Re: [v4 1/4] drm/panel-simple: Add basic DPCD backlight support From: Lyude Paul To: Rajeev Nandan , y@qualcomm.com, dri-devel@lists.freedesktop.org, linux-arm-msm@vger.kernel.org, freedreno@lists.freedesktop.org, devicetree@vger.kernel.org Cc: linux-kernel@vger.kernel.org, thierry.reding@gmail.com, sam@ravnborg.org, robdclark@gmail.com, dianders@chromium.org, jani.nikula@intel.com, robh@kernel.org, laurent.pinchart@ideasonboard.com, a.hajda@samsung.com, daniel.thompson@linaro.org, hoegsberg@chromium.org, abhinavk@codeaurora.org, seanpaul@chromium.org, kalyan_t@codeaurora.org, mkrishn@codeaurora.org Date: Tue, 01 Jun 2021 18:20:29 -0400 In-Reply-To: <1621927831-29471-2-git-send-email-rajeevny@codeaurora.org> References: <1621927831-29471-1-git-send-email-rajeevny@codeaurora.org> <1621927831-29471-2-git-send-email-rajeevny@codeaurora.org> Organization: Red Hat Content-Type: text/plain; charset="UTF-8" User-Agent: Evolution 3.38.4 (3.38.4-1.fc33) MIME-Version: 1.0 Content-Transfer-Encoding: 8bit Precedence: bulk List-ID: X-Mailing-List: linux-arm-msm@vger.kernel.org oh-looks like my patches just got reviewed, so hopefully I should get a chance to get a look at this in the next day or two :) On Tue, 2021-05-25 at 13:00 +0530, Rajeev Nandan wrote: > Add basic support of panel backlight control over eDP aux channel > using VESA's standard backlight control interface. > > Signed-off-by: Rajeev Nandan > --- > > This patch depends on [1] (drm/panel: panel-simple: Stash DP AUX bus; > allow using it for DDC) > > Changes in v4: > - New > > [1] > https://lore.kernel.org/dri-devel/20210524165920.v8.7.I18e60221f6d048d14d6c50a770b15f356fa75092@changeid/ > >  drivers/gpu/drm/panel/panel-simple.c | 99 > ++++++++++++++++++++++++++++++++++-- >  1 file changed, 96 insertions(+), 3 deletions(-) > > diff --git a/drivers/gpu/drm/panel/panel-simple.c > b/drivers/gpu/drm/panel/panel-simple.c > index b09be6e..f9e4e60 100644 > --- a/drivers/gpu/drm/panel/panel-simple.c > +++ b/drivers/gpu/drm/panel/panel-simple.c > @@ -21,6 +21,7 @@ >   * DEALINGS IN THE SOFTWARE. >   */ >   > +#include >  #include >  #include >  #include > @@ -171,6 +172,19 @@ struct panel_desc { >   >         /** @connector_type: LVDS, eDP, DSI, DPI, etc. */ >         int connector_type; > + > +       /** > +        * @uses_dpcd_backlight: Panel supports eDP dpcd backlight control. > +        * > +        * Set true, if the panel supports backlight control over eDP AUX > channel > +        * using DPCD registers as per VESA's standard. > +        */ > +       bool uses_dpcd_backlight; > +}; > + > +struct edp_backlight { > +       struct backlight_device *dev; > +       struct drm_edp_backlight_info info; >  }; >   >  struct panel_simple { > @@ -194,6 +208,8 @@ struct panel_simple { >   >         struct edid *edid; >   > +       struct edp_backlight *edp_bl; > + >         struct drm_display_mode override_mode; >   >         enum drm_panel_orientation orientation; > @@ -330,10 +346,14 @@ static void panel_simple_wait(ktime_t start_ktime, > unsigned int min_ms) >  static int panel_simple_disable(struct drm_panel *panel) >  { >         struct panel_simple *p = to_panel_simple(panel); > +       struct edp_backlight *bl = p->edp_bl; >   >         if (!p->enabled) >                 return 0; >   > +       if (p->desc->uses_dpcd_backlight && bl) > +               drm_edp_backlight_disable(p->aux, &bl->info); > + >         if (p->desc->delay.disable) >                 msleep(p->desc->delay.disable); >   > @@ -496,6 +516,7 @@ static int panel_simple_prepare(struct drm_panel *panel) >  static int panel_simple_enable(struct drm_panel *panel) >  { >         struct panel_simple *p = to_panel_simple(panel); > +       struct edp_backlight *bl = p->edp_bl; >   >         if (p->enabled) >                 return 0; > @@ -505,6 +526,10 @@ static int panel_simple_enable(struct drm_panel *panel) >   >         panel_simple_wait(p->prepared_time, p->desc- > >delay.prepare_to_enable); >   > +       if (p->desc->uses_dpcd_backlight && bl) > +               drm_edp_backlight_enable(p->aux, &bl->info, > +                                        bl->dev->props.brightness); > + >         p->enabled = true; >   >         return 0; > @@ -565,6 +590,59 @@ static const struct drm_panel_funcs panel_simple_funcs > = { >         .get_timings = panel_simple_get_timings, >  }; >   > +static int edp_backlight_update_status(struct backlight_device *bd) > +{ > +       struct panel_simple *p = bl_get_data(bd); > +       struct edp_backlight *bl = p->edp_bl; > + > +       if (!p->enabled) > +               return 0; > + > +       return drm_edp_backlight_set_level(p->aux, &bl->info, bd- > >props.brightness); > +} > + > +static const struct backlight_ops edp_backlight_ops = { > +       .update_status = edp_backlight_update_status, > +}; > + > +static int edp_backlight_register(struct device *dev, struct panel_simple > *panel) > +{ > +       struct edp_backlight *bl; > +       struct backlight_properties props = { 0 }; > +       u16 current_level; > +       u8 current_mode; > +       u8 edp_dpcd[EDP_DISPLAY_CTL_CAP_SIZE]; > +       int ret; > + > +       bl = devm_kzalloc(dev, sizeof(*bl), GFP_KERNEL); > +       if (!bl) > +               return -ENOMEM; > + > +       ret = drm_dp_dpcd_read(panel->aux, DP_EDP_DPCD_REV, edp_dpcd, > +                              EDP_DISPLAY_CTL_CAP_SIZE); > +       if (ret < 0) > +               return ret; > + > +       ret = drm_edp_backlight_init(panel->aux, &bl->info, 0, edp_dpcd, > +                                    ¤t_level, ¤t_mode); > +       if (ret < 0) > +               return ret; > + > +       props.type = BACKLIGHT_RAW; > +       props.brightness = current_level; > +       props.max_brightness = bl->info.max; > + > +       bl->dev = devm_backlight_device_register(dev, "edp_backlight", > +                                               dev, panel, > +                                               &edp_backlight_ops, &props); > +       if (IS_ERR(bl->dev)) > +               return PTR_ERR(bl->dev); > + > +       panel->edp_bl = bl; > + > +       return 0; > +} > + >  static struct panel_desc panel_dpi; >   >  static int panel_dpi_probe(struct device *dev, > @@ -796,9 +874,24 @@ static int panel_simple_probe(struct device *dev, const > struct panel_desc *desc, >   >         drm_panel_init(&panel->base, dev, &panel_simple_funcs, > connector_type); >   > -       err = drm_panel_of_backlight(&panel->base); > -       if (err) > -               goto disable_pm_runtime; > +       if (panel->desc->uses_dpcd_backlight) { > +               if (!panel->aux) { > +                       dev_err(dev, "edp backlight needs DP aux\n"); > +                       err = -EINVAL; > +                       goto disable_pm_runtime; > +               } > + > +               err = edp_backlight_register(dev, panel); > +               if (err) { > +                       dev_err(dev, "failed to register edp backlight > %d\n", err); > +                       goto disable_pm_runtime; > +               } > + > +       } else { > +               err = drm_panel_of_backlight(&panel->base); > +               if (err) > +                       goto disable_pm_runtime; > +       } >   >         drm_panel_add(&panel->base); >   -- Cheers, Lyude Paul (she/her) Software Engineer at Red Hat 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=-10.8 required=3.0 tests=BAYES_00,DKIM_INVALID, DKIM_SIGNED,HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_CR_TRAILER,INCLUDES_PATCH, MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS,UNWANTED_LANGUAGE_BODY autolearn=unavailable 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 B9494C47093 for ; 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[108.49.102.102]) by smtp.gmail.com with ESMTPSA id f130sm161456qke.37.2021.06.01.15.20.29 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Tue, 01 Jun 2021 15:20:30 -0700 (PDT) Message-ID: <4df7dcddd5aca799361642ea91c37fa94e8a4fef.camel@redhat.com> Subject: Re: [v4 1/4] drm/panel-simple: Add basic DPCD backlight support From: Lyude Paul To: Rajeev Nandan , y@qualcomm.com, dri-devel@lists.freedesktop.org, linux-arm-msm@vger.kernel.org, freedreno@lists.freedesktop.org, devicetree@vger.kernel.org Date: Tue, 01 Jun 2021 18:20:29 -0400 In-Reply-To: <1621927831-29471-2-git-send-email-rajeevny@codeaurora.org> References: <1621927831-29471-1-git-send-email-rajeevny@codeaurora.org> <1621927831-29471-2-git-send-email-rajeevny@codeaurora.org> Organization: Red Hat User-Agent: Evolution 3.38.4 (3.38.4-1.fc33) MIME-Version: 1.0 Authentication-Results: relay.mimecast.com; auth=pass smtp.auth=CUSA124A263 smtp.mailfrom=lyude@redhat.com X-Mimecast-Spam-Score: 0 X-Mimecast-Originator: redhat.com Content-Type: text/plain; charset="UTF-8" Content-Transfer-Encoding: 8bit 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: daniel.thompson@linaro.org, mkrishn@codeaurora.org, jani.nikula@intel.com, linux-kernel@vger.kernel.org, abhinavk@codeaurora.org, dianders@chromium.org, a.hajda@samsung.com, thierry.reding@gmail.com, seanpaul@chromium.org, laurent.pinchart@ideasonboard.com, kalyan_t@codeaurora.org, hoegsberg@chromium.org, sam@ravnborg.org Errors-To: dri-devel-bounces@lists.freedesktop.org Sender: "dri-devel" oh-looks like my patches just got reviewed, so hopefully I should get a chance to get a look at this in the next day or two :) On Tue, 2021-05-25 at 13:00 +0530, Rajeev Nandan wrote: > Add basic support of panel backlight control over eDP aux channel > using VESA's standard backlight control interface. > > Signed-off-by: Rajeev Nandan > --- > > This patch depends on [1] (drm/panel: panel-simple: Stash DP AUX bus; > allow using it for DDC) > > Changes in v4: > - New > > [1] > https://lore.kernel.org/dri-devel/20210524165920.v8.7.I18e60221f6d048d14d6c50a770b15f356fa75092@changeid/ > >  drivers/gpu/drm/panel/panel-simple.c | 99 > ++++++++++++++++++++++++++++++++++-- >  1 file changed, 96 insertions(+), 3 deletions(-) > > diff --git a/drivers/gpu/drm/panel/panel-simple.c > b/drivers/gpu/drm/panel/panel-simple.c > index b09be6e..f9e4e60 100644 > --- a/drivers/gpu/drm/panel/panel-simple.c > +++ b/drivers/gpu/drm/panel/panel-simple.c > @@ -21,6 +21,7 @@ >   * DEALINGS IN THE SOFTWARE. >   */ >   > +#include >  #include >  #include >  #include > @@ -171,6 +172,19 @@ struct panel_desc { >   >         /** @connector_type: LVDS, eDP, DSI, DPI, etc. */ >         int connector_type; > + > +       /** > +        * @uses_dpcd_backlight: Panel supports eDP dpcd backlight control. > +        * > +        * Set true, if the panel supports backlight control over eDP AUX > channel > +        * using DPCD registers as per VESA's standard. > +        */ > +       bool uses_dpcd_backlight; > +}; > + > +struct edp_backlight { > +       struct backlight_device *dev; > +       struct drm_edp_backlight_info info; >  }; >   >  struct panel_simple { > @@ -194,6 +208,8 @@ struct panel_simple { >   >         struct edid *edid; >   > +       struct edp_backlight *edp_bl; > + >         struct drm_display_mode override_mode; >   >         enum drm_panel_orientation orientation; > @@ -330,10 +346,14 @@ static void panel_simple_wait(ktime_t start_ktime, > unsigned int min_ms) >  static int panel_simple_disable(struct drm_panel *panel) >  { >         struct panel_simple *p = to_panel_simple(panel); > +       struct edp_backlight *bl = p->edp_bl; >   >         if (!p->enabled) >                 return 0; >   > +       if (p->desc->uses_dpcd_backlight && bl) > +               drm_edp_backlight_disable(p->aux, &bl->info); > + >         if (p->desc->delay.disable) >                 msleep(p->desc->delay.disable); >   > @@ -496,6 +516,7 @@ static int panel_simple_prepare(struct drm_panel *panel) >  static int panel_simple_enable(struct drm_panel *panel) >  { >         struct panel_simple *p = to_panel_simple(panel); > +       struct edp_backlight *bl = p->edp_bl; >   >         if (p->enabled) >                 return 0; > @@ -505,6 +526,10 @@ static int panel_simple_enable(struct drm_panel *panel) >   >         panel_simple_wait(p->prepared_time, p->desc- > >delay.prepare_to_enable); >   > +       if (p->desc->uses_dpcd_backlight && bl) > +               drm_edp_backlight_enable(p->aux, &bl->info, > +                                        bl->dev->props.brightness); > + >         p->enabled = true; >   >         return 0; > @@ -565,6 +590,59 @@ static const struct drm_panel_funcs panel_simple_funcs > = { >         .get_timings = panel_simple_get_timings, >  }; >   > +static int edp_backlight_update_status(struct backlight_device *bd) > +{ > +       struct panel_simple *p = bl_get_data(bd); > +       struct edp_backlight *bl = p->edp_bl; > + > +       if (!p->enabled) > +               return 0; > + > +       return drm_edp_backlight_set_level(p->aux, &bl->info, bd- > >props.brightness); > +} > + > +static const struct backlight_ops edp_backlight_ops = { > +       .update_status = edp_backlight_update_status, > +}; > + > +static int edp_backlight_register(struct device *dev, struct panel_simple > *panel) > +{ > +       struct edp_backlight *bl; > +       struct backlight_properties props = { 0 }; > +       u16 current_level; > +       u8 current_mode; > +       u8 edp_dpcd[EDP_DISPLAY_CTL_CAP_SIZE]; > +       int ret; > + > +       bl = devm_kzalloc(dev, sizeof(*bl), GFP_KERNEL); > +       if (!bl) > +               return -ENOMEM; > + > +       ret = drm_dp_dpcd_read(panel->aux, DP_EDP_DPCD_REV, edp_dpcd, > +                              EDP_DISPLAY_CTL_CAP_SIZE); > +       if (ret < 0) > +               return ret; > + > +       ret = drm_edp_backlight_init(panel->aux, &bl->info, 0, edp_dpcd, > +                                    ¤t_level, ¤t_mode); > +       if (ret < 0) > +               return ret; > + > +       props.type = BACKLIGHT_RAW; > +       props.brightness = current_level; > +       props.max_brightness = bl->info.max; > + > +       bl->dev = devm_backlight_device_register(dev, "edp_backlight", > +                                               dev, panel, > +                                               &edp_backlight_ops, &props); > +       if (IS_ERR(bl->dev)) > +               return PTR_ERR(bl->dev); > + > +       panel->edp_bl = bl; > + > +       return 0; > +} > + >  static struct panel_desc panel_dpi; >   >  static int panel_dpi_probe(struct device *dev, > @@ -796,9 +874,24 @@ static int panel_simple_probe(struct device *dev, const > struct panel_desc *desc, >   >         drm_panel_init(&panel->base, dev, &panel_simple_funcs, > connector_type); >   > -       err = drm_panel_of_backlight(&panel->base); > -       if (err) > -               goto disable_pm_runtime; > +       if (panel->desc->uses_dpcd_backlight) { > +               if (!panel->aux) { > +                       dev_err(dev, "edp backlight needs DP aux\n"); > +                       err = -EINVAL; > +                       goto disable_pm_runtime; > +               } > + > +               err = edp_backlight_register(dev, panel); > +               if (err) { > +                       dev_err(dev, "failed to register edp backlight > %d\n", err); > +                       goto disable_pm_runtime; > +               } > + > +       } else { > +               err = drm_panel_of_backlight(&panel->base); > +               if (err) > +                       goto disable_pm_runtime; > +       } >   >         drm_panel_add(&panel->base); >   -- Cheers, Lyude Paul (she/her) Software Engineer at Red Hat