From patchwork Mon Jan 16 11:08:20 2023 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Pin-yen Lin X-Patchwork-Id: 643206 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 04F6DC63797 for ; Mon, 16 Jan 2023 11:08:51 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S230287AbjAPLIs (ORCPT ); Mon, 16 Jan 2023 06:08:48 -0500 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:38686 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S231131AbjAPLIm (ORCPT ); Mon, 16 Jan 2023 06:08:42 -0500 Received: from mail-pj1-x1035.google.com (mail-pj1-x1035.google.com [IPv6:2607:f8b0:4864:20::1035]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 781DD14E88 for ; Mon, 16 Jan 2023 03:08:37 -0800 (PST) Received: by mail-pj1-x1035.google.com with SMTP id v23so28769274pju.3 for ; Mon, 16 Jan 2023 03:08:37 -0800 (PST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=chromium.org; s=google; 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=MsvXLO2LYgwrnisIBmhtUopgzlBZbEZ9q2CJUnQASFU=; b=jZHjclFFTN0lRqOF+89ClWqRX1oUTkgGLOjH/COUNSuLdHxmbhEaGXwnyUszMIBc2Y 9PNg7kYoSl76o6nHKi4SmCGe6OTTF78uMSn3T94qr1toSq+ZTiEUUOUDiItwRikXYU43 rtE6s9pWWJbzbBQMAPPiXA6Yq7uzYhz5OmYLI= X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20210112; 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=MsvXLO2LYgwrnisIBmhtUopgzlBZbEZ9q2CJUnQASFU=; b=WnHaa+pYpsxO5EagLpeT5dA8DZriiAGrXleN79nQHNsv2LyfVcO2Q8pumVPLEWr0Ev 4Cf43iT6DEBzivt8wIPtCfRaL7wR82B8PW1uC1/vvvjAnjvlPJvwLTWMXWAJdkt6mfAn cNAFw7cKXWiYc6vCad4twhjVfuJLX3JNJa7A3nGj+L+Rdrs7eDufKOE2w1gDR2RnDiRl 46r1xcfyCjf5HRT5O5sSijFT0+mn6fl98Se+innJdGRLcOrQ2hxAMDb+mOfwyhMVrd1/ OgXGbuSDekGamUWf/feHMAuYaQwI+FnLffQiu4Hsp7u48fogNJ2gF/cg6O6pSfa3e4ag O8GA== X-Gm-Message-State: AFqh2kpL0uyz2aXkkSpr2ruuEm15vddQVfMn3WXRGihZ9hJfh2jjTffA rVxRvOZ81zLr0IwJDeL9xFqJ9g== X-Google-Smtp-Source: AMrXdXs7sZF20EwrOSd/udSpFKMG+YWv5OfX+8QSfkMx/v6NRPXCaLivCKVs96K/psgoK7zovgOrZw== X-Received: by 2002:a17:90b:2747:b0:21a:1b9b:139e with SMTP id qi7-20020a17090b274700b0021a1b9b139emr93039821pjb.8.1673867316896; Mon, 16 Jan 2023 03:08:36 -0800 (PST) Received: from treapking.tpe.corp.google.com ([2401:fa00:1:10:a3f3:9ba9:fe36:fbcb]) by smtp.gmail.com with ESMTPSA id i8-20020a17090a138800b00226369149cesm17993686pja.21.2023.01.16.03.08.34 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Mon, 16 Jan 2023 03:08:36 -0800 (PST) From: Pin-yen Lin To: Andrzej Hajda , Neil Armstrong , Robert Foss , Laurent Pinchart , Jonas Karlman , Jernej Skrabec , David Airlie , Daniel Vetter , Rob Herring , Krzysztof Kozlowski Cc: Nicolas Boichat , devicetree@vger.kernel.org, linux-kernel@vger.kernel.org, Hsin-Yi Wang , dri-devel@lists.freedesktop.org, Pin-yen Lin Subject: [PATCH v2 2/2] drm: bridge: Generic GPIO mux driver Date: Mon, 16 Jan 2023 19:08:20 +0800 Message-Id: <20230116110820.2615650-3-treapking@chromium.org> X-Mailer: git-send-email 2.39.0.314.g84b9a713c41-goog In-Reply-To: <20230116110820.2615650-1-treapking@chromium.org> References: <20230116110820.2615650-1-treapking@chromium.org> MIME-Version: 1.0 Precedence: bulk List-ID: X-Mailing-List: devicetree@vger.kernel.org From: Nicolas Boichat This driver supports single input, 2 output display mux (e.g. HDMI mux), that provide its status via a GPIO. Signed-off-by: Nicolas Boichat Signed-off-by: Pin-yen Lin --- Laurent in v1 pointed out that the driver doesn't support panels as a downstream. IIUC this can be done by using drm_of_find_panel_or_bridge callback, but we don't have the hardware for this use case for testing. Changes in v2: - Dropped attach/mode_set/enable/disable callbacks - Fixed style issues - Removed the special case for the HDMI connector - Made the driver only read the GPIO status in IRQ handler - Rebased to drm-misc-next - Updated the license: "GPL v2" --> "GPL" drivers/gpu/drm/bridge/Kconfig | 10 ++ drivers/gpu/drm/bridge/Makefile | 1 + drivers/gpu/drm/bridge/generic-gpio-mux.c | 201 ++++++++++++++++++++++ 3 files changed, 212 insertions(+) create mode 100644 drivers/gpu/drm/bridge/generic-gpio-mux.c diff --git a/drivers/gpu/drm/bridge/Kconfig b/drivers/gpu/drm/bridge/Kconfig index 57946d80b02d..28f2221bc900 100644 --- a/drivers/gpu/drm/bridge/Kconfig +++ b/drivers/gpu/drm/bridge/Kconfig @@ -84,6 +84,16 @@ config DRM_FSL_LDB help Support for i.MX8MP DPI-to-LVDS on-SoC encoder. +config DRM_GENERIC_GPIO_MUX + tristate "Generic GPIO-controlled mux" + depends on OF + select DRM_KMS_HELPER + help + This bridge driver models a GPIO-controlled display mux with one + input, 2 outputs (e.g. an HDMI mux). The hardware decides which output + is active, reports it as a GPIO, and the driver redirects calls to the + appropriate downstream bridge (if any). + config DRM_ITE_IT6505 tristate "ITE IT6505 DisplayPort bridge" depends on OF diff --git a/drivers/gpu/drm/bridge/Makefile b/drivers/gpu/drm/bridge/Makefile index 1884803c6860..f5cfab100e8a 100644 --- a/drivers/gpu/drm/bridge/Makefile +++ b/drivers/gpu/drm/bridge/Makefile @@ -5,6 +5,7 @@ obj-$(CONFIG_DRM_CHRONTEL_CH7033) += chrontel-ch7033.o obj-$(CONFIG_DRM_CROS_EC_ANX7688) += cros-ec-anx7688.o obj-$(CONFIG_DRM_DISPLAY_CONNECTOR) += display-connector.o obj-$(CONFIG_DRM_FSL_LDB) += fsl-ldb.o +obj-$(CONFIG_DRM_GENERIC_GPIO_MUX) += generic-gpio-mux.o obj-$(CONFIG_DRM_ITE_IT6505) += ite-it6505.o obj-$(CONFIG_DRM_LONTIUM_LT8912B) += lontium-lt8912b.o obj-$(CONFIG_DRM_LONTIUM_LT9211) += lontium-lt9211.o diff --git a/drivers/gpu/drm/bridge/generic-gpio-mux.c b/drivers/gpu/drm/bridge/generic-gpio-mux.c new file mode 100644 index 000000000000..9c26abab7778 --- /dev/null +++ b/drivers/gpu/drm/bridge/generic-gpio-mux.c @@ -0,0 +1,201 @@ +// SPDX-License-Identifier: GPL-2.0-only +/* + * Generic gpio mux bridge driver + * + * Copyright 2016 Google LLC + */ + +#include +#include +#include +#include +#include +#include +#include + +#include +#include +#include + +struct gpio_display_mux { + struct device *dev; + + struct gpio_desc *gpiod_detect; + int detect_irq; + int cur_next; + + struct drm_bridge bridge; + + struct drm_bridge *next[2]; +}; + +static inline struct gpio_display_mux *bridge_to_gpio_display_mux( + struct drm_bridge *bridge) +{ + return container_of(bridge, struct gpio_display_mux, bridge); +} + +static irqreturn_t gpio_display_mux_det_threaded_handler(int unused, void *data) +{ + struct gpio_display_mux *mux = data; + int active = gpiod_get_value(mux->gpiod_detect); + + if (active < 0) { + dev_err(mux->dev, "Failed to get detect GPIO\n"); + return IRQ_HANDLED; + } + + dev_dbg(mux->dev, "Interrupt %d!\n", active); + mux->cur_next = active; + + if (mux->bridge.dev) + drm_kms_helper_hotplug_event(mux->bridge.dev); + + return IRQ_HANDLED; +} + +static bool gpio_display_mux_mode_fixup(struct drm_bridge *bridge, + const struct drm_display_mode *mode, + struct drm_display_mode *adjusted_mode) +{ + struct gpio_display_mux *mux = bridge_to_gpio_display_mux(bridge); + struct drm_bridge *next; + + next = mux->next[mux->cur_next]; + + /* Assume that we have a most one bridge in both downstreams */ + if (next && next->funcs->mode_fixup) + return next->funcs->mode_fixup(next, mode, adjusted_mode); + + return true; +} + +static const struct drm_bridge_funcs gpio_display_mux_bridge_funcs = { + .mode_fixup = gpio_display_mux_mode_fixup, +}; + +static int gpio_display_mux_probe(struct platform_device *pdev) +{ + struct device *dev = &pdev->dev; + struct gpio_display_mux *mux; + struct device_node *port, *ep, *remote; + int ret; + u32 reg; + + mux = devm_kzalloc(dev, sizeof(*mux), GFP_KERNEL); + if (!mux) + return -ENOMEM; + + platform_set_drvdata(pdev, mux); + mux->dev = &pdev->dev; + + mux->bridge.of_node = dev->of_node; + + mux->gpiod_detect = devm_gpiod_get(dev, "detect", GPIOD_IN); + if (IS_ERR(mux->gpiod_detect)) + return PTR_ERR(mux->gpiod_detect); + + mux->detect_irq = gpiod_to_irq(mux->gpiod_detect); + if (mux->detect_irq < 0) { + dev_err(dev, "Failed to get output irq %d\n", + mux->detect_irq); + return -ENODEV; + } + + port = of_graph_get_port_by_id(dev->of_node, 1); + if (!port) { + dev_err(dev, "Missing output port node\n"); + return -EINVAL; + } + + for_each_child_of_node(port, ep) { + if (!ep->name || (of_node_cmp(ep->name, "endpoint") != 0)) { + of_node_put(ep); + continue; + } + + if (of_property_read_u32(ep, "reg", ®) < 0 || + reg >= ARRAY_SIZE(mux->next)) { + dev_err(dev, + "Missing/invalid reg property for endpoint %s\n", + ep->full_name); + of_node_put(ep); + of_node_put(port); + return -EINVAL; + } + + remote = of_graph_get_remote_port_parent(ep); + if (!remote) { + dev_err(dev, + "Missing connector/bridge node for endpoint %s\n", + ep->full_name); + of_node_put(ep); + of_node_put(port); + return -EINVAL; + } + + mux->next[reg] = of_drm_find_bridge(remote); + if (!mux->next[reg]) { + dev_err(dev, "Waiting for external bridge %s\n", + remote->name); + of_node_put(ep); + of_node_put(remote); + of_node_put(port); + return -EPROBE_DEFER; + } + + of_node_put(remote); + } + of_node_put(port); + + mux->bridge.funcs = &gpio_display_mux_bridge_funcs; + mux->bridge.type = DRM_MODE_CONNECTOR_DisplayPort; + drm_bridge_add(&mux->bridge); + + ret = devm_request_threaded_irq(dev, mux->detect_irq, NULL, + gpio_display_mux_det_threaded_handler, + IRQF_TRIGGER_RISING | + IRQF_TRIGGER_FALLING | IRQF_ONESHOT, + "gpio-display-mux-det", mux); + if (ret) { + dev_err(dev, "Failed to request MUX_DET threaded irq\n"); + goto err_bridge_remove; + } + + return 0; + +err_bridge_remove: + drm_bridge_remove(&mux->bridge); + + return ret; +} + +static int gpio_display_mux_remove(struct platform_device *pdev) +{ + struct gpio_display_mux *mux = platform_get_drvdata(pdev); + + disable_irq(mux->detect_irq); + drm_bridge_remove(&mux->bridge); + + return 0; +} + +static const struct of_device_id gpio_display_mux_match[] = { + { .compatible = "gpio-display-mux", }, + {}, +}; + +struct platform_driver gpio_display_mux_driver = { + .probe = gpio_display_mux_probe, + .remove = gpio_display_mux_remove, + .driver = { + .name = "gpio-display-mux", + .of_match_table = gpio_display_mux_match, + }, +}; + +module_platform_driver(gpio_display_mux_driver); + +MODULE_DESCRIPTION("GPIO-controlled display mux"); +MODULE_AUTHOR("Nicolas Boichat "); +MODULE_LICENSE("GPL");