From nobody Sat Oct 4 15:59:04 2025 Received: from perceval.ideasonboard.com (perceval.ideasonboard.com [213.167.242.64]) (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 2D4412E92D5; Thu, 14 Aug 2025 11:38:34 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=213.167.242.64 ARC-Seal: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1755171516; cv=none; b=G4LQn1eAr9+OBAx4MtVlrGVVrjRMrW2xRJutcoROwORi0pbSsvlUbTuc8lHp5SZ+orZRc178F/cEmOa11V4O0cwTfoRqDxyUlz2ktJkRALS3FpwNW2VKjCpDdZHw44kuBqcQoBGvUi8xdNsfR7l7pANfMfb6bmExTGnfqquL92o= ARC-Message-Signature: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1755171516; c=relaxed/simple; bh=0/kcF88SImS98m2EJ/3g0BxMqg048eR3mnkGCn/omCw=; h=From:To:Cc:Subject:Date:Message-ID:MIME-Version; b=KE+wKrOl0D34Dj4fXshZ3iGz6tSje9QFAXxjG68YnchNNGRSbsuDcTt+NgSwMRRaQwAOVwJfXMd2ZoUHU3KAqLYA0FV1t9pDzvvVRt2zGn1RPUkFoqx2J+kKUL5zr5hJEolnBSzJbDVo0uiJmR5wEuYFS8Q8QOuWLIDIBB7Dy+8= ARC-Authentication-Results: i=1; smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=ideasonboard.com; spf=pass smtp.mailfrom=ideasonboard.com; dkim=pass (1024-bit key) header.d=ideasonboard.com header.i=@ideasonboard.com header.b=DcZYdkyJ; arc=none smtp.client-ip=213.167.242.64 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=ideasonboard.com Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=ideasonboard.com Authentication-Results: smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=ideasonboard.com header.i=@ideasonboard.com header.b="DcZYdkyJ" Received: from isaac-ThinkPad-T16-Gen-2.lan (cpc89244-aztw30-2-0-cust6594.18-1.cable.virginm.net [86.31.185.195]) by perceval.ideasonboard.com (Postfix) with ESMTPSA id 9620656D; Thu, 14 Aug 2025 13:37:37 +0200 (CEST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=ideasonboard.com; s=mail; t=1755171458; bh=0/kcF88SImS98m2EJ/3g0BxMqg048eR3mnkGCn/omCw=; h=From:To:Cc:Subject:Date:From; b=DcZYdkyJtE7iKxlaazF5aqwf7ef1TLMB/qs+dLqzuAZa3jgIp/Z6xe897brQpiNcl EkuEOt/v/4yoW5I5FRAN2LikH7Qtz+hmf/lJWoGJxxbKSHrxIMgElYiiBNYn50djeE E+ZQhHj41JcoFWgQWcd9dRWL9vtGfVOSRBtdTYcM= From: Isaac Scott To: linux-media@vger.kernel.org Cc: rmfrfs@gmail.com, laurent.pinchart@ideasonboard.com, martink@posteo.de, kernel@puri.sm, mchehab@kernel.org, shawnguo@kernel.org, s.hauer@pengutronix.de, kernel@pengutronix.de, festevam@gmail.com, imx@lists.linux.dev, linux-arm-kernel@lists.infradead.org, linux-kernel@vger.kernel.org, Isaac Scott Subject: [PATCH] imx-mipi-csis: Get the number of active lanes from mbus_config Date: Thu, 14 Aug 2025 12:37:01 +0100 Message-ID: <20250814113701.165644-1-isaac.scott@ideasonboard.com> X-Mailer: git-send-email 2.43.0 Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Transfer-Encoding: quoted-printable Content-Type: text/plain; charset="utf-8" Although 4 lanes may be physically available, we may not be using all of them. Get the number of configured lanes in the case a driver has implemented the get_mbus_config op. Signed-off-by: Isaac Scott --- Currently, the imx-mipi-csis driver parses the device tree to determine the number of configured lanes for the CSI receiver. This may be incorrect in the case that the connected device only uses a subset of lanes, for example. Allow the drivers for these cameras to create a mbus_config to configure the number of lanes that are actually being used. If the driver does not support the get_mbus_config op, this patch will have no functional change. Compile tested against media-master (v6.17-rc1) --- drivers/media/platform/nxp/imx-mipi-csis.c | 41 ++++++++++++++++++++++ 1 file changed, 41 insertions(+) diff --git a/drivers/media/platform/nxp/imx-mipi-csis.c b/drivers/media/pla= tform/nxp/imx-mipi-csis.c index 2beb5f43c2c0..efe4e2ad0382 100644 --- a/drivers/media/platform/nxp/imx-mipi-csis.c +++ b/drivers/media/platform/nxp/imx-mipi-csis.c @@ -939,6 +939,43 @@ static struct mipi_csis_device *sd_to_mipi_csis_device= (struct v4l2_subdev *sdev) return container_of(sdev, struct mipi_csis_device, sd); } =20 +static int mipi_csis_get_active_lanes(struct v4l2_subdev *sd) +{ + struct mipi_csis_device *csis =3D sd_to_mipi_csis_device(sd); + struct v4l2_mbus_config mbus_config =3D { 0 }; + int ret; + + ret =3D v4l2_subdev_call(csis->source.sd, pad, get_mbus_config, + 0, &mbus_config); + if (ret =3D=3D -ENOIOCTLCMD) { + dev_dbg(csis->dev, "No remote mbus configuration available\n"); + return 0; + } + + if (ret) { + dev_err(csis->dev, "Failed to get remote mbus configuration\n"); + return ret; + } + + if (mbus_config.type !=3D V4L2_MBUS_CSI2_DPHY) { + dev_err(csis->dev, "Unsupported media bus type %u\n", + mbus_config.type); + return -EINVAL; + } + + if (mbus_config.bus.mipi_csi2.num_data_lanes > csis->bus.num_data_lanes) { + dev_err(csis->dev, + "Unsupported mbus config: too many data lanes %u\n", + mbus_config.bus.mipi_csi2.num_data_lanes); + return -EINVAL; + } + + csis->bus.num_data_lanes =3D mbus_config.bus.mipi_csi2.num_data_lanes; + dev_dbg(csis->dev, "Number of lanes: %d\n", csis->bus.num_data_lanes); + + return 0; +} + static int mipi_csis_s_stream(struct v4l2_subdev *sd, int enable) { struct mipi_csis_device *csis =3D sd_to_mipi_csis_device(sd); @@ -965,6 +1002,10 @@ static int mipi_csis_s_stream(struct v4l2_subdev *sd,= int enable) format =3D v4l2_subdev_state_get_format(state, CSIS_PAD_SINK); csis_fmt =3D find_csis_format(format->code); =20 + ret =3D mipi_csis_get_active_lanes(sd); + if (ret < 0) + dev_dbg(csis->dev, "Failed to get active lanes: %d", ret); + ret =3D mipi_csis_calculate_params(csis, csis_fmt); if (ret < 0) goto err_unlock; --=20 2.43.0