From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from mail-m49201.qiye.163.com (mail-m49201.qiye.163.com [45.254.49.201]) (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 70D09288C08; Mon, 3 Nov 2025 06:29:32 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=45.254.49.201 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1762151376; cv=none; b=rjLGe4nTgT+geSBQMsPEjf/+/r4VWnp7+NVqYKpbpQrQPIYHOSuWr7QAuaUqrkO2Ql3wg6YqFLJEe+IlNPFVWaZpghyn3CtHHoFIGCcQe0Y6LZoEMvhSrl84ApH2z1/Wp3l0CZ8UQf/cTT4Is1wUw4WxbAN4RfgQPA+UmmxZfdQ= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1762151376; c=relaxed/simple; bh=FYwo4zwSk3jx+ryXlP0ZVCcTq6kno2ApjDwElUcKZq0=; h=Message-ID:Date:MIME-Version:Subject:To:Cc:References:From: In-Reply-To:Content-Type; b=OnGh2ApgwokKQAzAxPMuMAE1iEG28yu6Jni6kKMkFYN/AAiqiFzmjgevVgWN+WbDvJmcb/0j+z054Hg4FI0HMDl4AjVx7mDYcMn2i3c8PTyift11I0HdjTH5JU0j+D+5NfKDZbMdCBFMrVPgkVeLWabVWwkz1txqFgYTn0Lhqio= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=rock-chips.com; spf=pass smtp.mailfrom=rock-chips.com; dkim=pass (1024-bit key) header.d=rock-chips.com header.i=@rock-chips.com header.b=KLLEHfL+; arc=none smtp.client-ip=45.254.49.201 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=rock-chips.com Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=rock-chips.com Authentication-Results: smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=rock-chips.com header.i=@rock-chips.com header.b="KLLEHfL+" Received: from [172.16.12.149] (unknown [58.22.7.114]) by smtp.qiye.163.com (Hmail) with ESMTP id 28250c7cf; Mon, 3 Nov 2025 14:24:13 +0800 (GMT+08:00) Message-ID: Date: Mon, 3 Nov 2025 14:24:12 +0800 Precedence: bulk X-Mailing-List: devicetree@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 User-Agent: Mozilla Thunderbird Subject: Re: [PATCH v8 03/10] drm/bridge: Implement generic USB Type-C DP HPD bridge To: Dmitry Baryshkov , Chaoyi Chen Cc: Heikki Krogerus , Greg Kroah-Hartman , Rob Herring , Krzysztof Kozlowski , Conor Dooley , Vinod Koul , Kishon Vijay Abraham I , Heiko Stuebner , Sandy Huang , Andy Yan , Yubing Zhang , Frank Wang , Andrzej Hajda , Neil Armstrong , Robert Foss , Laurent Pinchart , Jonas Karlman , Jernej Skrabec , Maarten Lankhorst , Maxime Ripard , Thomas Zimmermann , David Airlie , Simona Vetter , Amit Sunil Dhamne , Dragan Simic , Johan Jonker , Diederik de Haas , Peter Robinson , linux-usb@vger.kernel.org, devicetree@vger.kernel.org, linux-kernel@vger.kernel.org, linux-phy@lists.infradead.org, linux-arm-kernel@lists.infradead.org, linux-rockchip@lists.infradead.org, dri-devel@lists.freedesktop.org References: <20251029071435.88-1-kernel@airkyi.com> <20251029071435.88-4-kernel@airkyi.com> Content-Language: en-US From: Chaoyi Chen In-Reply-To: Content-Type: text/plain; charset=UTF-8; format=flowed Content-Transfer-Encoding: 7bit X-HM-Tid: 0a9a4863370503abkunmdcf094ba9ba717 X-HM-MType: 1 X-HM-Spam-Status: e1kfGhgUHx5ZQUpXWQgPGg8OCBgUHx5ZQUlOS1dZFg8aDwILHllBWSg2Ly tZV1koWUFDSUNOT01LS0k3V1ktWUFJV1kPCRoVCBIfWUFZGUsdSVZPGUJDGB9KSEhJQhpWFRQJFh oXVRMBExYaEhckFA4PWVdZGBILWUFZTkNVSUlVTFVKSk9ZV1kWGg8SFR0UWUFZT0tIVUpLSEpOTE 9VSktLVUpCS0tZBg++ DKIM-Signature: a=rsa-sha256; b=KLLEHfL+eT0sjodZKmu60DNsnGd0BPXPm5ay685/jsdk/72KHGZ0UiGeNL2GEQAKZUdlSGuGXhrz+pcd7pL56fYgCYnfMhNrSnhqMBPKaXuop6Ybm3fvKwz1CN1DkV9k5/9fijJ7eQYFrgLXOTCjJ0vWbVkexNiveEuh3nFC8Ms=; s=default; c=relaxed/relaxed; d=rock-chips.com; v=1; bh=gBgZDKPDJM4JV2dVqNS/6faO3isIevqJbpBh6wQkg3U=; h=date:mime-version:subject:message-id:from; On 11/3/2025 12:00 PM, Dmitry Baryshkov wrote: > On Wed, Oct 29, 2025 at 03:14:28PM +0800, Chaoyi Chen wrote: >> From: Chaoyi Chen >> >> Several USB-C controller drivers have already implemented the DP HPD >> bridge function provided by aux-hpd-bridge.c, but there are still >> some USB-C controller driver that have not yet implemented it. >> >> This patch implements a generic DP HPD bridge based on aux-hpd-bridge.c, >> so that other USB-C controller drivers don't need to implement it again. > This doesn't describe the problem that you are trying to solve. I'll try to describe the information more accurately. Thank you. > >> Signed-off-by: Chaoyi Chen >> --- >> >> Changes in v8: >> - Merge generic DP HPD bridge into one module. >> >> drivers/gpu/drm/bridge/Kconfig | 5 +- >> drivers/gpu/drm/bridge/Makefile | 8 +++- >> drivers/gpu/drm/bridge/aux-hpd-bridge.c | 23 ++++++++- >> drivers/gpu/drm/bridge/aux-hpd-bridge.h | 13 +++++ >> .../gpu/drm/bridge/aux-hpd-typec-dp-bridge.c | 47 +++++++++++++++++++ >> 5 files changed, 93 insertions(+), 3 deletions(-) >> create mode 100644 drivers/gpu/drm/bridge/aux-hpd-bridge.h >> create mode 100644 drivers/gpu/drm/bridge/aux-hpd-typec-dp-bridge.c >> >> diff --git a/drivers/gpu/drm/bridge/Kconfig b/drivers/gpu/drm/bridge/Kconfig >> index a250afd8d662..17257b223a28 100644 >> --- a/drivers/gpu/drm/bridge/Kconfig >> +++ b/drivers/gpu/drm/bridge/Kconfig >> @@ -23,13 +23,16 @@ config DRM_AUX_BRIDGE >> build bridges chain. >> >> config DRM_AUX_HPD_BRIDGE >> - tristate >> + tristate "AUX HPD bridge support" > Why? No, this is supposed to be selected by other drivers. Users don't > know an wouldn't know what is this. In v7, I implemented an additional module for selecting this option. But Heikki believes that it would be better to merge the two modules into one. > >> depends on DRM_BRIDGE && OF >> select AUXILIARY_BUS >> help >> Simple bridge that terminates the bridge chain and provides HPD >> support. >> >> + Specifically, if you want a default Type-C DisplayPort HPD bridge for >> + each port of the Type-C controller, say Y here. >> + >> menu "Display Interface Bridges" >> depends on DRM && DRM_BRIDGE >> >> diff --git a/drivers/gpu/drm/bridge/Makefile b/drivers/gpu/drm/bridge/Makefile >> index c7dc03182e59..2998937444bc 100644 >> --- a/drivers/gpu/drm/bridge/Makefile >> +++ b/drivers/gpu/drm/bridge/Makefile >> @@ -1,6 +1,12 @@ >> # SPDX-License-Identifier: GPL-2.0 >> obj-$(CONFIG_DRM_AUX_BRIDGE) += aux-bridge.o >> -obj-$(CONFIG_DRM_AUX_HPD_BRIDGE) += aux-hpd-bridge.o >> + >> +hpd-bridge-y := aux-hpd-bridge.o >> +ifneq ($(CONFIG_TYPEC),) >> +hpd-bridge-y += aux-hpd-typec-dp-bridge.o >> +endif >> +obj-$(CONFIG_DRM_AUX_HPD_BRIDGE) += hpd-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-hpd-bridge.c b/drivers/gpu/drm/bridge/aux-hpd-bridge.c >> index 2e9c702c7087..11ad6dc776c7 100644 >> --- a/drivers/gpu/drm/bridge/aux-hpd-bridge.c >> +++ b/drivers/gpu/drm/bridge/aux-hpd-bridge.c >> @@ -12,6 +12,8 @@ >> #include >> #include >> >> +#include "aux-hpd-bridge.h" >> + >> static DEFINE_IDA(drm_aux_hpd_bridge_ida); >> >> struct drm_aux_hpd_bridge_data { >> @@ -204,7 +206,26 @@ static struct auxiliary_driver drm_aux_hpd_bridge_drv = { >> .id_table = drm_aux_hpd_bridge_table, >> .probe = drm_aux_hpd_bridge_probe, >> }; >> -module_auxiliary_driver(drm_aux_hpd_bridge_drv); >> + >> +static int drm_aux_hpd_bridge_mod_init(void) >> +{ >> + int ret; >> + >> + ret = auxiliary_driver_register(&drm_aux_hpd_bridge_drv); >> + if (ret) >> + return ret; >> + >> + return drm_aux_hpd_typec_dp_bridge_init(); >> +} >> + >> +static void drm_aux_hpd_bridge_mod_exit(void) >> +{ >> + drm_aux_hpd_typec_dp_bridge_exit(); >> + auxiliary_driver_unregister(&drm_aux_hpd_bridge_drv); >> +} >> + >> +module_init(drm_aux_hpd_bridge_mod_init); >> +module_exit(drm_aux_hpd_bridge_mod_exit); >> >> MODULE_AUTHOR("Dmitry Baryshkov "); >> MODULE_DESCRIPTION("DRM HPD bridge"); >> diff --git a/drivers/gpu/drm/bridge/aux-hpd-bridge.h b/drivers/gpu/drm/bridge/aux-hpd-bridge.h >> new file mode 100644 >> index 000000000000..69364731c2f1 >> --- /dev/null >> +++ b/drivers/gpu/drm/bridge/aux-hpd-bridge.h >> @@ -0,0 +1,13 @@ >> +/* SPDX-License-Identifier: GPL-2.0-only */ >> +#ifndef AUX_HPD_BRIDGE_H >> +#define AUX_HPD_BRIDGE_H >> + >> +#if IS_REACHABLE(CONFIG_TYPEC) >> +int drm_aux_hpd_typec_dp_bridge_init(void); >> +void drm_aux_hpd_typec_dp_bridge_exit(void); >> +#else >> +static inline int drm_aux_hpd_typec_dp_bridge_init(void) { return 0; } >> +static inline void drm_aux_hpd_typec_dp_bridge_exit(void) { } >> +#endif /* IS_REACHABLE(CONFIG_TYPEC) */ >> + >> +#endif /* AUX_HPD_BRIDGE_H */ >> diff --git a/drivers/gpu/drm/bridge/aux-hpd-typec-dp-bridge.c b/drivers/gpu/drm/bridge/aux-hpd-typec-dp-bridge.c >> new file mode 100644 >> index 000000000000..6f2a1fca0fc5 >> --- /dev/null >> +++ b/drivers/gpu/drm/bridge/aux-hpd-typec-dp-bridge.c >> @@ -0,0 +1,47 @@ >> +// SPDX-License-Identifier: GPL-2.0+ >> +#include >> +#include >> +#include >> +#include >> + >> +#include >> + >> +#include "aux-hpd-bridge.h" >> + >> +#if IS_REACHABLE(CONFIG_TYPEC) >> +static int drm_typec_bus_event(struct notifier_block *nb, >> + unsigned long action, void *data) >> +{ > This feels like this should be a part of the Type-C subsystem rather > than DRM. In v7, this used to be a part of the Type-C subsystem. I'm not sure what Heikki thinks about this. > >> + struct typec_altmode *alt = (struct typec_altmode *)data; >> + >> + if (action != TYPEC_ALTMODE_REGISTERED) >> + goto done; >> + >> + if (is_typec_partner(&alt->dev) || alt->svid != USB_TYPEC_DP_SID) >> + goto done; >> + >> + /* >> + * alt->dev.parent->parent : USB-C controller device >> + * alt->dev.parent : USB-C connector device >> + */ >> + drm_dp_hpd_bridge_register(alt->dev.parent->parent, >> + to_of_node(alt->dev.parent->fwnode)); >> + >> +done: >> + return NOTIFY_OK; >> +} >> + >> +static struct notifier_block drm_typec_event_nb = { >> + .notifier_call = drm_typec_bus_event, >> +}; >> + >> +int drm_aux_hpd_typec_dp_bridge_init(void) >> +{ >> + return typec_altmode_register_notify(&drm_typec_event_nb); >> +} >> + >> +void drm_aux_hpd_typec_dp_bridge_exit(void) >> +{ >> + typec_altmode_unregister_notify(&drm_typec_event_nb); >> +} >> +#endif >> -- >> 2.49.0 >> -- Best, Chaoyi