From patchwork Thu Aug 17 14:55:14 2023 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Dmitry Baryshkov X-Patchwork-Id: 715166 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id DDB45C3063F for ; Thu, 17 Aug 2023 14:55:56 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1352390AbjHQOz3 (ORCPT ); Thu, 17 Aug 2023 10:55:29 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:37696 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1352461AbjHQOzW (ORCPT ); Thu, 17 Aug 2023 10:55:22 -0400 Received: from mail-lj1-x233.google.com (mail-lj1-x233.google.com [IPv6:2a00:1450:4864:20::233]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id C04AF10E for ; Thu, 17 Aug 2023 07:55:20 -0700 (PDT) Received: by mail-lj1-x233.google.com with SMTP id 38308e7fff4ca-2b9cdba1228so124305571fa.2 for ; Thu, 17 Aug 2023 07:55:20 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=linaro.org; s=google; t=1692284119; x=1692888919; h=content-transfer-encoding:mime-version:references:in-reply-to :message-id:date:subject:cc:to:from:from:to:cc:subject:date :message-id:reply-to; bh=2vhTfY3zK1nVXfsOliBavlrx/Dt9Fzo1Rikffhx9+p0=; b=AmgUV4Z9qwiBpLYMHbQtoMUbk/VRKBrLCzBeqsCTpNFaOySDPctPDbEipM+jBzXuOE wYEU2rO2sFW70QtO3OlrnVBYykgFq8/U5BA8qDqFo90BbJYQKiNkscfT+B52DipPvBAU 14EtUEtbUUPnJeDSuUwEqfM/ygpU93BifgFtUNEHm4FsZeJpGLoyZsjT6m+I88u71EtW DtRbP5punFYmSqy1dhwseQOmHoY1c2U8LeDkiQXghbsUSQs+kxytQd6M7Ua1nd5xEDPt PM48x4525S1MqeIKgq7Go/Mow0v7ptZRRXlWhN3t6uSFD0tuY+JFc/T5gLhbfCGtghb9 ITcg== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20221208; t=1692284119; x=1692888919; h=content-transfer-encoding:mime-version:references:in-reply-to :message-id:date:subject:cc:to:from:x-gm-message-state:from:to:cc :subject:date:message-id:reply-to; bh=2vhTfY3zK1nVXfsOliBavlrx/Dt9Fzo1Rikffhx9+p0=; b=eP+r/JMXf1cY9b6prboe2ipwzlqTcPoBDdXCGrk1deDsNBqGLXxJo3uemY293Gx5Is 1zlE+6RoHIUYO0RP6G7YHauq9pOElIpWv+RxIcHPzHKIStpe3QQKkWRzoZ8AdRor61XF b3WhgPMMfRroSMjyFcidtYb8BVZLUfAPOLuRh9yknUzzaQL6Xqy4xFkxwxNDNcy3D43y jtAqpH121HKBk6MssbJa3hIBPOBg3ioTvT9s3ggCUXSogSEIacH4447UOjxE9iGZDv27 zkR2zY+QXODIKsRxI57UVq5b3Hq6hoiRTbyPxtZSLaRVq214vHke8jRsGtKTyQzGsjIQ f+Hg== X-Gm-Message-State: AOJu0YyYkR6s6T64ad/vTf25H1bRaTcWBuVayiaODTH8ZVST98u4MB27 faBEPtDAhmubXbOIuPiwymmcpw== X-Google-Smtp-Source: AGHT+IHkRzzSXWRQP0qaL0WJk3ZsyEZedw9qJr5xyOynBevDyNI6fYm9ZYWFW789J3N+rmZtzKahyw== X-Received: by 2002:a2e:7c0f:0:b0:2b6:fa71:5bae with SMTP id x15-20020a2e7c0f000000b002b6fa715baemr4485793ljc.12.1692284118896; Thu, 17 Aug 2023 07:55:18 -0700 (PDT) Received: from umbar.unikie.fi ([192.130.178.91]) by smtp.gmail.com with ESMTPSA id z13-20020a2e350d000000b002b9e5fe86dasm4082728ljz.81.2023.08.17.07.55.17 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Thu, 17 Aug 2023 07:55:18 -0700 (PDT) From: Dmitry Baryshkov To: David Airlie , Daniel Vetter , Andrzej Hajda , Neil Armstrong , Robert Foss , Laurent Pinchart , Jonas Karlman , Jernej Skrabec , Andy Gross , Bjorn Andersson , Konrad Dybcio , Vinod Koul , Kishon Vijay Abraham I , Heikki Krogerus , Greg Kroah-Hartman Cc: dri-devel@lists.freedesktop.org, linux-arm-msm@vger.kernel.org, linux-phy@lists.infradead.org, linux-usb@vger.kernel.org, freedreno@lists.freedesktop.org Subject: [PATCH v4 1/3] drm/bridge: add transparent bridge helper Date: Thu, 17 Aug 2023 17:55:14 +0300 Message-Id: <20230817145516.5924-2-dmitry.baryshkov@linaro.org> X-Mailer: git-send-email 2.39.2 In-Reply-To: <20230817145516.5924-1-dmitry.baryshkov@linaro.org> References: <20230817145516.5924-1-dmitry.baryshkov@linaro.org> MIME-Version: 1.0 Precedence: bulk List-ID: X-Mailing-List: linux-usb@vger.kernel.org Define a helper for creating simple transparent bridges which serve the only purpose of linking devices into the bridge chain up to the last bridge representing the connector. This is especially useful for DP/USB-C bridge chains, which can span across several devices, but do not require any additional functionality from the intermediate bridges. Signed-off-by: Dmitry Baryshkov --- drivers/gpu/drm/bridge/Kconfig | 9 ++ drivers/gpu/drm/bridge/Makefile | 1 + drivers/gpu/drm/bridge/aux-bridge.c | 132 ++++++++++++++++++++++++++++ include/drm/bridge/aux-bridge.h | 19 ++++ 4 files changed, 161 insertions(+) create mode 100644 drivers/gpu/drm/bridge/aux-bridge.c create mode 100644 include/drm/bridge/aux-bridge.h diff --git a/drivers/gpu/drm/bridge/Kconfig b/drivers/gpu/drm/bridge/Kconfig index 44a660a4bdbf..80e5d9f722e4 100644 --- a/drivers/gpu/drm/bridge/Kconfig +++ b/drivers/gpu/drm/bridge/Kconfig @@ -12,6 +12,15 @@ config DRM_PANEL_BRIDGE help DRM bridge wrapper of DRM panels +config DRM_AUX_BRIDGE + tristate + depends on DRM_BRIDGE && OF + select AUXILIARY_BUS + select DRM_PANEL_BRIDGE + help + Simple transparent bridge that is used by several non-DRM drivers to + build bridges chain. + menu "Display Interface Bridges" depends on DRM && DRM_BRIDGE diff --git a/drivers/gpu/drm/bridge/Makefile b/drivers/gpu/drm/bridge/Makefile index 2b892b7ed59e..918e3bfff079 100644 --- a/drivers/gpu/drm/bridge/Makefile +++ b/drivers/gpu/drm/bridge/Makefile @@ -1,4 +1,5 @@ # SPDX-License-Identifier: GPL-2.0 +obj-$(CONFIG_DRM_AUX_BRIDGE) += aux-bridge.o obj-$(CONFIG_DRM_CHIPONE_ICN6211) += chipone-icn6211.o obj-$(CONFIG_DRM_CHRONTEL_CH7033) += chrontel-ch7033.o obj-$(CONFIG_DRM_CROS_EC_ANX7688) += cros-ec-anx7688.o diff --git a/drivers/gpu/drm/bridge/aux-bridge.c b/drivers/gpu/drm/bridge/aux-bridge.c new file mode 100644 index 000000000000..13fe794592f2 --- /dev/null +++ b/drivers/gpu/drm/bridge/aux-bridge.c @@ -0,0 +1,132 @@ +// SPDX-License-Identifier: GPL-2.0+ +/* + * Copyright (C) 2023 Linaro Ltd. + * + * Author: Dmitry Baryshkov + */ +#include +#include + +#include +#include + +static DEFINE_IDA(aux_bridge_ida); + +static void drm_aux_bridge_release(struct device *dev) +{ + struct auxiliary_device *adev = to_auxiliary_dev(dev); + + ida_free(&aux_bridge_ida, adev->id); + + kfree(adev); +} + +static void drm_aux_bridge_unregister_adev(void *_adev) +{ + struct auxiliary_device *adev = _adev; + + auxiliary_device_delete(adev); + auxiliary_device_uninit(adev); +} + +int drm_aux_bridge_register(struct device *parent) +{ + struct auxiliary_device *adev; + int ret; + + adev = kzalloc(sizeof(*adev), GFP_KERNEL); + if (!adev) + return -ENOMEM; + + ret = ida_alloc(&aux_bridge_ida, GFP_KERNEL); + if (ret < 0) { + kfree(adev); + return ret; + } + + adev->id = ret; + adev->name = "aux_bridge"; + adev->dev.parent = parent; +#ifdef CONFIG_OF + adev->dev.of_node = parent->of_node; +#endif + adev->dev.release = drm_aux_bridge_release; + + ret = auxiliary_device_init(adev); + if (ret) { + ida_free(&aux_bridge_ida, adev->id); + kfree(adev); + return ret; + } + + ret = auxiliary_device_add(adev); + if (ret) { + auxiliary_device_uninit(adev); + return ret; + } + + return devm_add_action_or_reset(parent, drm_aux_bridge_unregister_adev, adev); +} +EXPORT_SYMBOL_GPL(drm_aux_bridge_register); + +struct drm_aux_bridge_data { + struct drm_bridge bridge; + struct drm_bridge *next_bridge; + struct device *dev; +}; + +static int drm_aux_bridge_attach(struct drm_bridge *bridge, + enum drm_bridge_attach_flags flags) +{ + struct drm_aux_bridge_data *data; + + if (!(flags & DRM_BRIDGE_ATTACH_NO_CONNECTOR)) + return -EINVAL; + + data = container_of(bridge, struct drm_aux_bridge_data, bridge); + + return drm_bridge_attach(bridge->encoder, data->next_bridge, bridge, + DRM_BRIDGE_ATTACH_NO_CONNECTOR); +} + +static const struct drm_bridge_funcs drm_aux_bridge_funcs = { + .attach = drm_aux_bridge_attach, +}; + +static int drm_aux_bridge_probe(struct auxiliary_device *auxdev, + const struct auxiliary_device_id *id) +{ + struct drm_aux_bridge_data *data; + + data = devm_kzalloc(&auxdev->dev, sizeof(*data), GFP_KERNEL); + if (!data) + return -ENOMEM; + + data->dev = &auxdev->dev; + data->next_bridge = devm_drm_of_get_bridge(&auxdev->dev, auxdev->dev.of_node, 0, 0); + if (IS_ERR(data->next_bridge)) + return dev_err_probe(&auxdev->dev, PTR_ERR(data->next_bridge), + "failed to acquire drm_bridge\n"); + + data->bridge.funcs = &drm_aux_bridge_funcs; + data->bridge.of_node = data->dev->of_node; + + return devm_drm_bridge_add(data->dev, &data->bridge); +} + +static const struct auxiliary_device_id drm_aux_bridge_table[] = { + { .name = KBUILD_MODNAME ".aux_bridge" }, + {}, +}; +MODULE_DEVICE_TABLE(auxiliary, drm_aux_bridge_table); + +static struct auxiliary_driver drm_aux_bridge_drv = { + .name = "aux_bridge", + .id_table = drm_aux_bridge_table, + .probe = drm_aux_bridge_probe, +}; +module_auxiliary_driver(drm_aux_bridge_drv); + +MODULE_AUTHOR("Dmitry Baryshkov "); +MODULE_DESCRIPTION("DRM transparent bridge"); +MODULE_LICENSE("GPL"); diff --git a/include/drm/bridge/aux-bridge.h b/include/drm/bridge/aux-bridge.h new file mode 100644 index 000000000000..441ab3f0e920 --- /dev/null +++ b/include/drm/bridge/aux-bridge.h @@ -0,0 +1,19 @@ +// SPDX-License-Identifier: GPL-2.0+ +/* + * Copyright (C) 2023 Linaro Ltd. + * + * Author: Dmitry Baryshkov + */ +#ifndef DRM_AUX_BRIDGE_H +#define DRM_AUX_BRIDGE_H + +#if IS_ENABLED(CONFIG_DRM_AUX_BRIDGE) +int drm_aux_bridge_register(struct device *parent); +#else +static inline int drm_aux_bridge_register(struct device *parent) +{ + return 0; +} +#endif + +#endif