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=-13.7 required=3.0 tests=BAYES_00, HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_CR_TRAILER,INCLUDES_PATCH, MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS,URIBL_BLOCKED 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 AD5A7C433DB for ; Wed, 23 Dec 2020 17:14:20 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 7E4282220B for ; Wed, 23 Dec 2020 17:14:20 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1726486AbgLWRN7 (ORCPT ); Wed, 23 Dec 2020 12:13:59 -0500 Received: from mga18.intel.com ([134.134.136.126]:24910 "EHLO mga18.intel.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1725807AbgLWRN6 (ORCPT ); Wed, 23 Dec 2020 12:13:58 -0500 IronPort-SDR: HdGn+CY8CVKo60kZFnvst30T4ylzBFQDQGUmlGB+7j42wd1Y7ilw+uEtWd43OzEUE8ykRwNmPp bqOZEwoTl09Q== X-IronPort-AV: E=McAfee;i="6000,8403,9844"; a="163766154" X-IronPort-AV: E=Sophos;i="5.78,441,1599548400"; d="scan'208";a="163766154" Received: from orsmga008.jf.intel.com ([10.7.209.65]) by orsmga106.jf.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 23 Dec 2020 09:13:09 -0800 IronPort-SDR: ZRDYyDgII9EV81cbu9GINTG/C+CEGbePUs2x/sqVgpJv3PLp/5cL5qe48KmzkvWK+9b/xnpHTR 1VfY1CzlJBvA== X-IronPort-AV: E=Sophos;i="5.78,441,1599548400"; d="scan'208";a="374062808" Received: from odonov3x-mobl.ger.corp.intel.com (HELO localhost) ([10.213.250.144]) by orsmga008-auth.jf.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 23 Dec 2020 09:12:58 -0800 From: Jani Nikula To: Lyude Paul , Rodrigo Vivi , Dave Airlie , intel-gfx@lists.freedesktop.org, dri-devel@lists.freedesktop.org Cc: thaytan@noraisin.net, Vasily Khoruzhick , Joonas Lahtinen , David Airlie , Daniel Vetter , Juha-Pekka Heikkila , Ville =?utf-8?B?U3lyasOkbMOk?= , Sean Paul , open list Subject: Re: [PATCH v3 8/9] drm/i915/dp: Allow forcing specific interfaces through enable_dpcd_backlight In-Reply-To: <20201204223603.249878-9-lyude@redhat.com> Organization: Intel Finland Oy - BIC 0357606-4 - Westendinkatu 7, 02160 Espoo References: <20201204223603.249878-1-lyude@redhat.com> <20201204223603.249878-9-lyude@redhat.com> Date: Wed, 23 Dec 2020 19:12:53 +0200 Message-ID: <87tuscmooa.fsf@intel.com> MIME-Version: 1.0 Content-Type: text/plain Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Fri, 04 Dec 2020, Lyude Paul wrote: > Since we now support controlling panel backlights through DPCD using > both the standard VESA interface, and Intel's proprietary HDR backlight > interface, we should allow the user to be able to explicitly choose > between one or the other in the event that we're wrong about panels > reliably reporting support for the Intel HDR interface. > > So, this commit adds support for this by introducing two new > enable_dpcd_backlight options: 2 which forces i915 to only probe for the > VESA interface, and 3 which forces i915 to only probe for the Intel > backlight interface (might be useful if we find panels in the wild that > report the VESA interface in their VBT, but actually only support the > Intel backlight interface). > > v3: > * Rebase > > Signed-off-by: Lyude Paul > Cc: thaytan@noraisin.net > Cc: Vasily Khoruzhick > --- > .../drm/i915/display/intel_dp_aux_backlight.c | 45 +++++++++++++++++-- > drivers/gpu/drm/i915/i915_params.c | 2 +- > 2 files changed, 43 insertions(+), 4 deletions(-) > > diff --git a/drivers/gpu/drm/i915/display/intel_dp_aux_backlight.c b/drivers/gpu/drm/i915/display/intel_dp_aux_backlight.c > index 9a3ff3ffc158..eef14ab6bddc 100644 > --- a/drivers/gpu/drm/i915/display/intel_dp_aux_backlight.c > +++ b/drivers/gpu/drm/i915/display/intel_dp_aux_backlight.c > @@ -609,15 +609,54 @@ static const struct intel_panel_bl_funcs intel_dp_vesa_bl_funcs = { > .get = intel_dp_aux_vesa_get_backlight, > }; > > +enum intel_dp_aux_backlight_modparam { > + INTEL_DP_AUX_BACKLIGHT_AUTO = -1, > + INTEL_DP_AUX_BACKLIGHT_OFF = 0, > + INTEL_DP_AUX_BACKLIGHT_ON = 1, > + INTEL_DP_AUX_BACKLIGHT_FORCE_VESA = 2, > + INTEL_DP_AUX_BACKLIGHT_FORCE_INTEL = 3, > +}; > + > int intel_dp_aux_init_backlight_funcs(struct intel_connector *connector) > { > struct drm_device *dev = connector->base.dev; > struct intel_panel *panel = &connector->panel; > struct intel_dp *intel_dp = enc_to_intel_dp(connector->encoder); > struct drm_i915_private *i915 = dp_to_i915(intel_dp); > + bool try_intel_interface = false, try_vesa_interface = false; > > - if (i915->params.enable_dpcd_backlight == 0) > + /* Check the VBT and user's module parameters to figure out which > + * interfaces to probe > + */ > + switch (i915->params.enable_dpcd_backlight) { > + case INTEL_DP_AUX_BACKLIGHT_OFF: > return -ENODEV; > + case INTEL_DP_AUX_BACKLIGHT_AUTO: > + switch (i915->vbt.backlight.type) { > + case INTEL_BACKLIGHT_VESA_EDP_AUX_INTERFACE: > + try_vesa_interface = true; > + break; > + case INTEL_BACKLIGHT_DISPLAY_DDI: > + try_intel_interface = true; I take it this is what the machines report? *rolls eyes*. > + try_vesa_interface = true; > + break; > + default: > + return -ENODEV; > + } > + break; > + case INTEL_DP_AUX_BACKLIGHT_ON: > + if (i915->vbt.backlight.type != INTEL_BACKLIGHT_VESA_EDP_AUX_INTERFACE) > + try_intel_interface = true; This could use an explanation - why not try the intel interface in this case? Anyway, good enough, Reviewed-by: Jani Nikula > + > + try_vesa_interface = true; > + break; > + case INTEL_DP_AUX_BACKLIGHT_FORCE_VESA: > + try_vesa_interface = true; > + break; > + case INTEL_DP_AUX_BACKLIGHT_FORCE_INTEL: > + try_intel_interface = true; > + break; > + } > > /* > * A lot of eDP panels in the wild will report supporting both the > @@ -626,13 +665,13 @@ int intel_dp_aux_init_backlight_funcs(struct intel_connector *connector) > * and will only work with the Intel interface. So, always probe for > * that first. > */ > - if (intel_dp_aux_supports_hdr_backlight(connector)) { > + if (try_intel_interface && intel_dp_aux_supports_hdr_backlight(connector)) { > drm_dbg(dev, "Using Intel proprietary eDP backlight controls\n"); > panel->backlight.funcs = &intel_dp_hdr_bl_funcs; > return 0; > } > > - if (intel_dp_aux_supports_vesa_backlight(connector)) { > + if (try_vesa_interface && intel_dp_aux_supports_vesa_backlight(connector)) { > drm_dbg(dev, "Using VESA eDP backlight controls\n"); > panel->backlight.funcs = &intel_dp_vesa_bl_funcs; > return 0; > diff --git a/drivers/gpu/drm/i915/i915_params.c b/drivers/gpu/drm/i915/i915_params.c > index 7f139ea4a90b..6939634e56ed 100644 > --- a/drivers/gpu/drm/i915/i915_params.c > +++ b/drivers/gpu/drm/i915/i915_params.c > @@ -185,7 +185,7 @@ i915_param_named_unsafe(inject_probe_failure, uint, 0400, > > i915_param_named(enable_dpcd_backlight, int, 0400, > "Enable support for DPCD backlight control" > - "(-1=use per-VBT LFP backlight type setting [default], 0=disabled, 1=enabled)"); > + "(-1=use per-VBT LFP backlight type setting [default], 0=disabled, 1=enable, 2=force VESA interface, 3=force Intel interface)"); > > #if IS_ENABLED(CONFIG_DRM_I915_GVT) > i915_param_named(enable_gvt, bool, 0400, -- Jani Nikula, Intel Open Source Graphics Center