From patchwork Mon Jan 31 08:55:20 2022 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 8bit X-Patchwork-Submitter: AngeloGioacchino Del Regno X-Patchwork-Id: 12730485 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 gabe.freedesktop.org (gabe.freedesktop.org [131.252.210.177]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.lore.kernel.org (Postfix) with ESMTPS id 6B76FC433FE for ; Mon, 31 Jan 2022 08:55:34 +0000 (UTC) Received: from gabe.freedesktop.org (localhost [127.0.0.1]) by gabe.freedesktop.org (Postfix) with ESMTP id 5FD5010FEDF; Mon, 31 Jan 2022 08:55:33 +0000 (UTC) Received: from bhuna.collabora.co.uk (bhuna.collabora.co.uk [46.235.227.227]) by gabe.freedesktop.org (Postfix) with ESMTPS id F402F10F9EA for ; Mon, 31 Jan 2022 08:55:31 +0000 (UTC) Received: from [127.0.0.1] (localhost [127.0.0.1]) (Authenticated sender: kholk11) with ESMTPSA id 612F11F4302A DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=collabora.com; s=mail; t=1643619330; bh=AXf56R+mRkAxLE1emIJ+KeI2b8KNGh0WluiTdMOniaQ=; h=From:To:Cc:Subject:Date:From; b=HOJE3bKxURe1A1NWeLZK4tFFhTScA0zVcr49UcMcsLlU7s0H4avY17NSkVocZuxHW /6iw2veP3wAAEiokRS2bko3k/ScNZNwbx4hTPiQPw3i2S0VPBmkbCaWAnrzVALVAdR MioiBkY2OuQHySb0Derc7Y0RpIXjbjmUNzZ4yRlq9DmsFbECYWsJYbu+v4N59WVLTB 6mviuHc6oUVDHq3Juf8dkmFH8w0DkmNMy8SWxZiN0piHp4xtdjJW25nYlHK5o5ROCw LsWpjZIig7dayeQ5EcXgcsCW6Uu/ceL/GqP3tTsoUugTS8r+QdkHZuyxcnay59cTT5 3iWNZ/WTVpSbw== From: AngeloGioacchino Del Regno To: dri-devel@lists.freedesktop.org Subject: [PATCH v4] drm/mediatek: mtk_dsi: Avoid EPROBE_DEFER loop with external bridge Date: Mon, 31 Jan 2022 09:55:20 +0100 Message-Id: <20220131085520.287105-1-angelogioacchino.delregno@collabora.com> X-Mailer: git-send-email 2.33.1 MIME-Version: 1.0 X-BeenThere: dri-devel@lists.freedesktop.org X-Mailman-Version: 2.1.29 Precedence: list List-Id: Direct Rendering Infrastructure - Development List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Cc: chunkuang.hu@kernel.org, airlied@linux.ie, linux-kernel@vger.kernel.org, stable@vger.kernel.org, andrzej.hajda@intel.com, linux-mediatek@lists.infradead.org, Jagan Teki , matthias.bgg@gmail.com, kernel@collabora.com, linux-arm-kernel@lists.infradead.org, AngeloGioacchino Del Regno Errors-To: dri-devel-bounces@lists.freedesktop.org Sender: "dri-devel" DRM bridge drivers are now attaching their DSI device at probe time, which requires us to register our DSI host in order to let the bridge to probe: this recently started producing an endless -EPROBE_DEFER loop on some machines that are using external bridges, like the parade-ps8640, found on the ACER Chromebook R13. Now that the DSI hosts/devices probe sequence is documented, we can do adjustments to the mtk_dsi driver as to both fix now and make sure to avoid this situation in the future: for this, following what is documented in drm_bridge.c, move the mtk_dsi component_add() to the mtk_dsi_ops.attach callback and delete it in the detach callback; keeping in mind that we are registering a drm_bridge for our DSI, which is only used/attached if the DSI Host is bound, it wouldn't make sense to keep adding our bridge at probe time (as it would be useless to have it if mtk_dsi_ops.attach() fails!), so also move that one to the dsi host attach function (and remove it in detach). Cc: # 5.15.x Signed-off-by: AngeloGioacchino Del Regno Reviewed-by: Andrzej Hajda Reviewed-by: Jagan Teki Reviewed-by: CK Hu Tested-by: Nícolas F. R. A. Prado --- drivers/gpu/drm/mediatek/mtk_dsi.c | 167 +++++++++++++++-------------- 1 file changed, 84 insertions(+), 83 deletions(-) diff --git a/drivers/gpu/drm/mediatek/mtk_dsi.c b/drivers/gpu/drm/mediatek/mtk_dsi.c index 5d90d2eb0019..bced4c7d668e 100644 --- a/drivers/gpu/drm/mediatek/mtk_dsi.c +++ b/drivers/gpu/drm/mediatek/mtk_dsi.c @@ -786,18 +786,101 @@ void mtk_dsi_ddp_stop(struct device *dev) mtk_dsi_poweroff(dsi); } +static int mtk_dsi_encoder_init(struct drm_device *drm, struct mtk_dsi *dsi) +{ + int ret; + + ret = drm_simple_encoder_init(drm, &dsi->encoder, + DRM_MODE_ENCODER_DSI); + if (ret) { + DRM_ERROR("Failed to encoder init to drm\n"); + return ret; + } + + dsi->encoder.possible_crtcs = mtk_drm_find_possible_crtc_by_comp(drm, dsi->host.dev); + + ret = drm_bridge_attach(&dsi->encoder, &dsi->bridge, NULL, + DRM_BRIDGE_ATTACH_NO_CONNECTOR); + if (ret) + goto err_cleanup_encoder; + + dsi->connector = drm_bridge_connector_init(drm, &dsi->encoder); + if (IS_ERR(dsi->connector)) { + DRM_ERROR("Unable to create bridge connector\n"); + ret = PTR_ERR(dsi->connector); + goto err_cleanup_encoder; + } + drm_connector_attach_encoder(dsi->connector, &dsi->encoder); + + return 0; + +err_cleanup_encoder: + drm_encoder_cleanup(&dsi->encoder); + return ret; +} + +static int mtk_dsi_bind(struct device *dev, struct device *master, void *data) +{ + int ret; + struct drm_device *drm = data; + struct mtk_dsi *dsi = dev_get_drvdata(dev); + + ret = mtk_dsi_encoder_init(drm, dsi); + if (ret) + return ret; + + return device_reset_optional(dev); +} + +static void mtk_dsi_unbind(struct device *dev, struct device *master, + void *data) +{ + struct mtk_dsi *dsi = dev_get_drvdata(dev); + + drm_encoder_cleanup(&dsi->encoder); +} + +static const struct component_ops mtk_dsi_component_ops = { + .bind = mtk_dsi_bind, + .unbind = mtk_dsi_unbind, +}; + static int mtk_dsi_host_attach(struct mipi_dsi_host *host, struct mipi_dsi_device *device) { struct mtk_dsi *dsi = host_to_dsi(host); + struct device *dev = host->dev; + int ret; dsi->lanes = device->lanes; dsi->format = device->format; dsi->mode_flags = device->mode_flags; + dsi->next_bridge = devm_drm_of_get_bridge(dev, dev->of_node, 0, 0); + if (IS_ERR(dsi->next_bridge)) + return PTR_ERR(dsi->next_bridge); + + drm_bridge_add(&dsi->bridge); + + ret = component_add(host->dev, &mtk_dsi_component_ops); + if (ret) { + DRM_ERROR("failed to add dsi_host component: %d\n", ret); + drm_bridge_remove(&dsi->bridge); + return ret; + } return 0; } +static int mtk_dsi_host_detach(struct mipi_dsi_host *host, + struct mipi_dsi_device *device) +{ + struct mtk_dsi *dsi = host_to_dsi(host); + + component_del(host->dev, &mtk_dsi_component_ops); + drm_bridge_remove(&dsi->bridge); + return 0; +} + static void mtk_dsi_wait_for_idle(struct mtk_dsi *dsi) { int ret; @@ -938,73 +1021,14 @@ static ssize_t mtk_dsi_host_transfer(struct mipi_dsi_host *host, static const struct mipi_dsi_host_ops mtk_dsi_ops = { .attach = mtk_dsi_host_attach, + .detach = mtk_dsi_host_detach, .transfer = mtk_dsi_host_transfer, }; -static int mtk_dsi_encoder_init(struct drm_device *drm, struct mtk_dsi *dsi) -{ - int ret; - - ret = drm_simple_encoder_init(drm, &dsi->encoder, - DRM_MODE_ENCODER_DSI); - if (ret) { - DRM_ERROR("Failed to encoder init to drm\n"); - return ret; - } - - dsi->encoder.possible_crtcs = mtk_drm_find_possible_crtc_by_comp(drm, dsi->host.dev); - - ret = drm_bridge_attach(&dsi->encoder, &dsi->bridge, NULL, - DRM_BRIDGE_ATTACH_NO_CONNECTOR); - if (ret) - goto err_cleanup_encoder; - - dsi->connector = drm_bridge_connector_init(drm, &dsi->encoder); - if (IS_ERR(dsi->connector)) { - DRM_ERROR("Unable to create bridge connector\n"); - ret = PTR_ERR(dsi->connector); - goto err_cleanup_encoder; - } - drm_connector_attach_encoder(dsi->connector, &dsi->encoder); - - return 0; - -err_cleanup_encoder: - drm_encoder_cleanup(&dsi->encoder); - return ret; -} - -static int mtk_dsi_bind(struct device *dev, struct device *master, void *data) -{ - int ret; - struct drm_device *drm = data; - struct mtk_dsi *dsi = dev_get_drvdata(dev); - - ret = mtk_dsi_encoder_init(drm, dsi); - if (ret) - return ret; - - return device_reset_optional(dev); -} - -static void mtk_dsi_unbind(struct device *dev, struct device *master, - void *data) -{ - struct mtk_dsi *dsi = dev_get_drvdata(dev); - - drm_encoder_cleanup(&dsi->encoder); -} - -static const struct component_ops mtk_dsi_component_ops = { - .bind = mtk_dsi_bind, - .unbind = mtk_dsi_unbind, -}; - static int mtk_dsi_probe(struct platform_device *pdev) { struct mtk_dsi *dsi; struct device *dev = &pdev->dev; - struct drm_panel *panel; struct resource *regs; int irq_num; int ret; @@ -1021,19 +1045,6 @@ static int mtk_dsi_probe(struct platform_device *pdev) return ret; } - ret = drm_of_find_panel_or_bridge(dev->of_node, 0, 0, - &panel, &dsi->next_bridge); - if (ret) - goto err_unregister_host; - - if (panel) { - dsi->next_bridge = devm_drm_panel_bridge_add(dev, panel); - if (IS_ERR(dsi->next_bridge)) { - ret = PTR_ERR(dsi->next_bridge); - goto err_unregister_host; - } - } - dsi->driver_data = of_device_get_match_data(dev); dsi->engine_clk = devm_clk_get(dev, "engine"); @@ -1098,14 +1109,6 @@ static int mtk_dsi_probe(struct platform_device *pdev) dsi->bridge.of_node = dev->of_node; dsi->bridge.type = DRM_MODE_CONNECTOR_DSI; - drm_bridge_add(&dsi->bridge); - - ret = component_add(&pdev->dev, &mtk_dsi_component_ops); - if (ret) { - dev_err(&pdev->dev, "failed to add component: %d\n", ret); - goto err_unregister_host; - } - return 0; err_unregister_host: @@ -1118,8 +1121,6 @@ static int mtk_dsi_remove(struct platform_device *pdev) struct mtk_dsi *dsi = platform_get_drvdata(pdev); mtk_output_dsi_disable(dsi); - drm_bridge_remove(&dsi->bridge); - component_del(&pdev->dev, &mtk_dsi_component_ops); mipi_dsi_host_unregister(&dsi->host); return 0;