From patchwork Tue Oct 10 23:10:16 2023 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Dmitry Baryshkov X-Patchwork-Id: 731875 Received: from lindbergh.monkeyblade.net (lindbergh.monkeyblade.net [23.128.96.19]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id 4E9C032C7D for ; Tue, 10 Oct 2023 23:10:24 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=linaro.org header.i=@linaro.org header.b="zUUVUb9n" Received: from mail-lj1-x22f.google.com (mail-lj1-x22f.google.com [IPv6:2a00:1450:4864:20::22f]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id EB2DC98 for ; Tue, 10 Oct 2023 16:10:21 -0700 (PDT) Received: by mail-lj1-x22f.google.com with SMTP id 38308e7fff4ca-2bffa8578feso77191021fa.2 for ; Tue, 10 Oct 2023 16:10:21 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=linaro.org; s=google; t=1696979420; x=1697584220; darn=vger.kernel.org; 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=8iE7CPNjZ9Do+9C0BlCLKs/6irh+RZEMFEZ53IvryGM=; b=zUUVUb9nSEBUazv5FzvhrZLwXkAZH7a+mzBpqiZAQM4q0gy8hAyumI4l5l4xC4jzOI Ej7qOLKMJdng4w3208a5gxVgoGfbzMI54DWANkbZgrgAfd/TvbQ/zKjoX6HfNN/XSTVS DbN90jqBHD1vEjHzAMeX0bHgtu3TNJtHfrp7if0QKvgflk/YevKPrf/aE948S7D2aniV aVWMAwk8WbxcJOcaMEzjKJi6NTrjbrkTWQBI3aXuxpu2tQ74rZQ2saInv3HKHPIhid9p DwLiGOhlk62lIDyC/1cgZvU8gJhAJLL8BRZtEOkSbKYorV3Vv+oOG6wkYsXY+CNpXf98 I4Lw== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20230601; t=1696979420; x=1697584220; 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=8iE7CPNjZ9Do+9C0BlCLKs/6irh+RZEMFEZ53IvryGM=; b=poiJhb/lBxbFdMeDg/iS1UXzFspe8MWEQeVNjn1ChQgUNzICH608fmSOG9esi+by7G mNqE4BxAcGaZuEqbeOywvVzuwewesXlxuAEkq4Q3FcRo8vqe/wGOV2r921D1boF34zSY Lfj8niz2s5J8xh5iRhMRTJPKca2zW9tuTbj87LtfbFod2TPXugAY06lmIPUgSYS1gGZe H9nrSZqahiXTfgaylrvBx6s6ilRbmMf2QAx5yqcaqPauL2zL2I98jCfPpTJ4dYa7rUjj rVxjO7kTDAHt0o5+VSF+1x5rKw+aBnmaKO2Gw26DDwGSCJIa2Lwdi2lDAZUCbbKMAeaa j0oQ== X-Gm-Message-State: AOJu0YzmiJbSWASrOlo4CtThpAsc2IndxxIX4MFv5fTXp8iWsE7RfIFN Tl1MW8uQET5cP9rrlGq0k5ZNgQ== X-Google-Smtp-Source: AGHT+IFgzesJ9dwuX9h/Cbfz2K21dtF8UtSa0RbnKtdBjHhEZJ/bjRYtjd6KfoB3tJOxwM8xe41axA== X-Received: by 2002:a2e:8914:0:b0:2c0:1385:8c86 with SMTP id d20-20020a2e8914000000b002c013858c86mr18255178lji.25.1696979420142; Tue, 10 Oct 2023 16:10:20 -0700 (PDT) Received: from umbar.unikie.fi ([192.130.178.91]) by smtp.gmail.com with ESMTPSA id n8-20020a2e8788000000b002bcdbfe36b9sm2658033lji.111.2023.10.10.16.10.19 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Tue, 10 Oct 2023 16:10:19 -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: Wed, 11 Oct 2023 02:10:16 +0300 Message-Id: <20231010231018.77381-2-dmitry.baryshkov@linaro.org> X-Mailer: git-send-email 2.39.2 In-Reply-To: <20231010231018.77381-1-dmitry.baryshkov@linaro.org> References: <20231010231018.77381-1-dmitry.baryshkov@linaro.org> Precedence: bulk X-Mailing-List: linux-usb@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 X-Spam-Status: No, score=-2.1 required=5.0 tests=BAYES_00,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_AU,DKIM_VALID_EF,RCVD_IN_DNSWL_NONE, SPF_HELO_NONE,SPF_PASS,URIBL_BLOCKED autolearn=ham autolearn_force=no version=3.4.6 X-Spam-Checker-Version: SpamAssassin 3.4.6 (2021-04-09) on lindbergh.monkeyblade.net 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 ba82a1142adf..f12eab62799f 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