From nobody Sun Sep 21 21:38:52 2025 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 ED5EDCDB465 for ; Mon, 16 Oct 2023 17:07:52 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S234607AbjJPQ5p (ORCPT ); Mon, 16 Oct 2023 12:57:45 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:56342 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S234370AbjJPQ4k (ORCPT ); Mon, 16 Oct 2023 12:56:40 -0400 Received: from mail-wm1-x333.google.com (mail-wm1-x333.google.com [IPv6:2a00:1450:4864:20::333]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 2DF2D1B9 for ; Mon, 16 Oct 2023 09:54:05 -0700 (PDT) Received: by mail-wm1-x333.google.com with SMTP id 5b1f17b1804b1-40535597f01so46839505e9.3 for ; Mon, 16 Oct 2023 09:54:05 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=linaro.org; s=google; t=1697475243; x=1698080043; 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=OLZfAioiQyP2GbHH4z94Kghh0UWm5WmSuFGJ712+5P8=; b=RxRgZE4sYeb4tEM3rATm0bRYUOboqRumrEcw4trJcYFi3YrOR3oQqnaVa0OxB0ijsx 0tKalTxlUAJwmw7+fWn6CqaZgnqtNfrpzyvmBiUqoMJ0zwvWcYw6g/Eng40gFTeRlEkp k3UNixOoWJVVjn/VkT3uz/4is9q4kBPbH+YksrTlCmjSh2em9ILiNRhmDiZ7QaNGjM9c iN9dlp39s3sji4zgMHnsLdSTTuvd/Yb0YUeDaMaQosJ+cBmnteq80XnabYt9uHiEwyFx qC5ISusovdfMfs9pAfUSJBpPcT68Rz8Zg3MZRNIRl5aR5RsQiRM3pCBzn9iWlb9kwwpz Ghsg== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20230601; t=1697475243; x=1698080043; 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=OLZfAioiQyP2GbHH4z94Kghh0UWm5WmSuFGJ712+5P8=; b=sJxLeidItU+92BezJVar3IYpVMMIAq22mPH5PYkufsdmi8vln6TIXNyLELJWdNtTs8 24rXdChca5M3ug2h8t44WeiaeUe8sAhSNJqkZOjmZMj9D0YPg7O/AXeTucAzHW2rhfHv KquibUEQlYaK2ExVHlk3it+yqmrM9Yy22TM6GENWcBuS5g0noGbcUU62SxFx0wIic3dp 4SJVXpWpHV98JrAxAabG4f2BM+wMuCWNjlzVUBIvU82J7+TXx+Ayt/NI6TxhwAtimEhG IcP9DdH3UzCcYS8wEobstmPGZoUw2GCUySv4wX2MscOIeW5ZzWANWmdC1e2astDlBZUR nPRQ== X-Gm-Message-State: AOJu0YxyKAdBKCK6nkS/jMv5CI5uq1e2Nb4OGP4Qjiy9bExrA6eLrNlk MSBhtLttNN4eNU+rcVGlq//FGg== X-Google-Smtp-Source: AGHT+IEBvJ0AZHZOH5C1QXJLEQY2GElyolulqaAir+SIzHoMEpjQbAyxb+WOdlGZX6IRMJmT8vnGLw== X-Received: by 2002:a05:600c:2242:b0:401:be70:53b6 with SMTP id a2-20020a05600c224200b00401be7053b6mr30210769wmm.15.1697475243658; Mon, 16 Oct 2023 09:54:03 -0700 (PDT) Received: from eriador.lumag.spb.ru ([45.84.211.189]) by smtp.gmail.com with ESMTPSA id s19-20020a05600c45d300b0040648217f4fsm7638996wmo.39.2023.10.16.09.54.01 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Mon, 16 Oct 2023 09:54:03 -0700 (PDT) From: Dmitry Baryshkov To: Dave Stevenson , Andrzej Hajda , Neil Armstrong , Robert Foss , Laurent Pinchart , Jonas Karlman , Jernej Skrabec , Maarten Lankhorst , Maxime Ripard , Thomas Zimmermann , David Airlie , Daniel Vetter , Douglas Anderson , Rob Clark , Abhinav Kumar , Dmitry Baryshkov , Sean Paul , Marijn Suijten , Konrad Dybcio , Jessica Zhang Cc: Marek Vasut , dri-devel@lists.freedesktop.org, linux-kernel@vger.kernel.org, linux-arm-msm@vger.kernel.org, freedreno@lists.freedesktop.org Subject: [RFC PATCH 03/10] drm/mipi-dsi: add API for manual control over the DSI link power state Date: Mon, 16 Oct 2023 19:53:48 +0300 Message-ID: <20231016165355.1327217-4-dmitry.baryshkov@linaro.org> X-Mailer: git-send-email 2.42.0 In-Reply-To: <20231016165355.1327217-1-dmitry.baryshkov@linaro.org> References: <20231016165355.1327217-1-dmitry.baryshkov@linaro.org> MIME-Version: 1.0 Content-Transfer-Encoding: quoted-printable Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Type: text/plain; charset="utf-8" The MIPI DSI links do not fully fall into the DRM callbacks model. The drm_bridge_funcs abstraction. Instead of having just two states (off and on) the DSI hosts have separate LP-11 state. In this state the host is on, but the video stream is not yet enabled. Introduce API that allows DSI bridges / panels to control the DSI host power up state. Signed-off-by: Dmitry Baryshkov --- drivers/gpu/drm/drm_mipi_dsi.c | 31 +++++++++++++++++++++++++++++++ include/drm/drm_mipi_dsi.h | 29 +++++++++++++++++++++++++---- 2 files changed, 56 insertions(+), 4 deletions(-) diff --git a/drivers/gpu/drm/drm_mipi_dsi.c b/drivers/gpu/drm/drm_mipi_dsi.c index 14201f73aab1..c467162cb7d8 100644 --- a/drivers/gpu/drm/drm_mipi_dsi.c +++ b/drivers/gpu/drm/drm_mipi_dsi.c @@ -428,6 +428,37 @@ int devm_mipi_dsi_attach(struct device *dev, } EXPORT_SYMBOL_GPL(devm_mipi_dsi_attach); =20 +bool mipi_dsi_host_power_control_available(struct mipi_dsi_host *host) +{ + const struct mipi_dsi_host_ops *ops =3D host->ops; + + return ops && ops->power_up; +} +EXPORT_SYMBOL_GPL(mipi_dsi_host_power_control_available); + +int mipi_dsi_host_power_up(struct mipi_dsi_host *host) +{ + const struct mipi_dsi_host_ops *ops =3D host->ops; + + if (!mipi_dsi_host_power_control_available(host)) + return -EOPNOTSUPP; + + return ops->power_up ? ops->power_up(host) : 0; +} +EXPORT_SYMBOL_GPL(mipi_dsi_host_power_up); + +void mipi_dsi_host_power_down(struct mipi_dsi_host *host) +{ + const struct mipi_dsi_host_ops *ops =3D host->ops; + + if (!mipi_dsi_host_power_control_available(host)) + return; + + if (ops->power_down) + ops->power_down(host); +} +EXPORT_SYMBOL_GPL(mipi_dsi_host_power_down); + static ssize_t mipi_dsi_device_transfer(struct mipi_dsi_device *dsi, struct mipi_dsi_msg *msg) { diff --git a/include/drm/drm_mipi_dsi.h b/include/drm/drm_mipi_dsi.h index 167742e579e3..e503c3e4d057 100644 --- a/include/drm/drm_mipi_dsi.h +++ b/include/drm/drm_mipi_dsi.h @@ -68,6 +68,8 @@ int mipi_dsi_create_packet(struct mipi_dsi_packet *packet, * @attach: attach DSI device to DSI host * @detach: detach DSI device from DSI host * @transfer: transmit a DSI packet + * @power_up: enable DSI link and bring it to the LP-11 state + * @power_down: fully disable DSI link * * DSI packets transmitted by .transfer() are passed in as mipi_dsi_msg * structures. This structure contains information about the type of packet @@ -81,10 +83,18 @@ int mipi_dsi_create_packet(struct mipi_dsi_packet *pack= et, * function will seldomly return anything other than the number of bytes * contained in the transmit buffer on success. * - * Also note that those callbacks can be called no matter the state the - * host is in. Drivers that need the underlying device to be powered to - * perform these operations will first need to make sure it's been - * properly enabled. + * Note: currently there are two modes of DSI power control. Legacy drivers + * will call those callbacks no matter the state the host is in. DSI host + * drivers that need the underlying device to be powered to perform these + * operations will first need to make sure it's been properly enabled. + * + * Newer drivers will set the @MIPI_DSI_MANUAL_POWERUP flag to indicate th= at + * they will call @mipi_dsi_power_up() and @mipi_dsi_power_down() to contr= ol + * the link state of the DSI host or they will set @MIPI_DSI_AUTO_POWERUP = to + * indicate that the driver is fine with the link being powered up in DSI + * host's (atomic_)pre_enable() callback and then being disabled in the + * (atomic_)post_disable() callback. The transfer callback must only be ca= lled + * if the DSI host has been powered up and was not brought down. * * Note: some hosts (sunxi) can not send LP commands between HS video * packets. Thus all DSI transfers sent in LP mode should be limited to the @@ -97,6 +107,8 @@ struct mipi_dsi_host_ops { struct mipi_dsi_device *dsi); ssize_t (*transfer)(struct mipi_dsi_host *host, const struct mipi_dsi_msg *msg); + int (*power_up)(struct mipi_dsi_host *host); + void (*power_down)(struct mipi_dsi_host *host); }; =20 /** @@ -143,6 +155,10 @@ struct mipi_dsi_host *of_find_mipi_dsi_host_by_node(st= ruct device_node *node); #define MIPI_DSI_MODE_LPM BIT(11) /* transmit data ending at the same time for all lanes within one hsync */ #define MIPI_DSI_HS_PKT_END_ALIGNED BIT(12) +/* DSI peripheral driver manually controls DSI link powerup */ +#define MIPI_DSI_MANUAL_POWERUP BIT(13) +/* DSI peripheral driver is fine with automatic DSI link power control */ +#define MIPI_DSI_AUTO_POWERUP BIT(14) =20 enum mipi_dsi_pixel_format { MIPI_DSI_FMT_RGB888, @@ -235,6 +251,11 @@ void mipi_dsi_device_unregister(struct mipi_dsi_device= *dsi); struct mipi_dsi_device * devm_mipi_dsi_device_register_full(struct device *dev, struct mipi_dsi_hos= t *host, const struct mipi_dsi_device_info *info); + +bool mipi_dsi_host_power_control_available(struct mipi_dsi_host *host); +int mipi_dsi_host_power_up(struct mipi_dsi_host *host); +void mipi_dsi_host_power_down(struct mipi_dsi_host *host); + struct mipi_dsi_device *of_find_mipi_dsi_device_by_node(struct device_node= *np); int mipi_dsi_attach(struct mipi_dsi_device *dsi); int mipi_dsi_detach(struct mipi_dsi_device *dsi); --=20 2.42.0