From patchwork Tue Nov 10 17:40:33 2020 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Jacopo Mondi X-Patchwork-Id: 323308 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-12.7 required=3.0 tests=BAYES_00, HEADER_FROM_DIFFERENT_DOMAINS, INCLUDES_PATCH, MAILING_LIST_MULTI, SIGNED_OFF_BY, SPF_HELO_NONE,SPF_PASS,URIBL_BLOCKED,USER_AGENT_GIT autolearn=ham autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id 0C987C55ABD for ; Tue, 10 Nov 2020 17:40:51 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id B3E6E207D3 for ; Tue, 10 Nov 2020 17:40:50 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1730382AbgKJRku (ORCPT ); Tue, 10 Nov 2020 12:40:50 -0500 Received: from relay9-d.mail.gandi.net ([217.70.183.199]:36057 "EHLO relay9-d.mail.gandi.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726557AbgKJRku (ORCPT ); Tue, 10 Nov 2020 12:40:50 -0500 X-Originating-IP: 93.34.118.233 Received: from uno.lan (93-34-118-233.ip49.fastwebnet.it [93.34.118.233]) (Authenticated sender: jacopo@jmondi.org) by relay9-d.mail.gandi.net (Postfix) with ESMTPSA id 33A9BFF807; Tue, 10 Nov 2020 17:40:46 +0000 (UTC) From: Jacopo Mondi To: linux-media@vger.kernel.org Cc: Jacopo Mondi , naush@raspberrypi.com, dave.stevenson@raspberrypi.com, laurent.pinchart@ideasonboard.com, kieran.bingham@ideasonboard.com, niklas.soderlund@ragnatech.se, dafna.hirschfeld@collabora.com, hverkuil@xs4all.nl, sakari.ailus@iki.fi, nsaenzjulienne@suse.de, mchehab+huawei@kernel.org Subject: [PATCH v4 2/5] dt-bindings: media: Document BCM283x CSI2/CCP2 receiver Date: Tue, 10 Nov 2020 18:40:33 +0100 Message-Id: <20201110174036.220883-3-jacopo@jmondi.org> X-Mailer: git-send-email 2.29.1 In-Reply-To: <20201110174036.220883-1-jacopo@jmondi.org> References: <20201110174036.220883-1-jacopo@jmondi.org> MIME-Version: 1.0 Precedence: bulk List-ID: X-Mailing-List: linux-media@vger.kernel.org From: Dave Stevenson Document the DT bindings for the CSI2/CCP2 receiver peripheral (known as Unicam) on BCM283x SoCs. Signed-off-by: Dave Stevenson Signed-off-by: Laurent Pinchart Signed-off-by: Jacopo Mondi --- .../bindings/media/brcm,bcm2835-unicam.yaml | 155 ++++++++++++++++++ 1 file changed, 155 insertions(+) create mode 100644 Documentation/devicetree/bindings/media/brcm,bcm2835-unicam.yaml diff --git a/Documentation/devicetree/bindings/media/brcm,bcm2835-unicam.yaml b/Documentation/devicetree/bindings/media/brcm,bcm2835-unicam.yaml new file mode 100644 index 0000000000000..6ffc900e8ae8f --- /dev/null +++ b/Documentation/devicetree/bindings/media/brcm,bcm2835-unicam.yaml @@ -0,0 +1,155 @@ +# SPDX-License-Identifier: (GPL-2.0-only OR BSD-2-Clause) +# Copyright (C) 2020 Raspberry Pi (Trading) Ltd. +%YAML 1.2 +--- +$id: http://devicetree.org/schemas/media/brcm,bcm2835-unicam.yaml# +$schema: http://devicetree.org/meta-schemas/core.yaml# + +title: Broadcom BCM283x Camera Interface (Unicam) + +maintainers: + - Dave Stevenson + - Raspberry Pi kernel list + +description: + The Unicam block on BCM283x SoCs is the receiver for either CSI-2 or CCP2 + data from image sensors or similar devices. + + The main platform using this SoC is the Raspberry Pi family of boards. On the + Pi the VideoCore firmware can also control this hardware block, and driving + it from two different processors will cause issues. To avoid this, the + firmware checks the device tree configuration during boot. If it finds device + tree nodes whose name starts with "csi" then it will stop the firmware + accessing the block, and it can then safely be used via the device tree + binding. + +properties: + compatible: + const: brcm,bcm2835-unicam + + reg: + items: + - description: Main registers block + - description: Clock registers block + + interrupts: + maxItems: 1 + + clocks: + minItems: 1 + maxItems: 2 + + clock-names: + minItems: 1 + items: + - const: lp + - const: core + + power-domains: + maxItems: 1 + + brcm,num-data-lanes: + description: + The number of data lanes supported by this Unicam instance. It may be + larger than the number of data lanes routed on the board, as described by + the data-lanes property of the endpoint. + allOf: + - $ref: "/schemas/types.yaml#/definitions/uint32" + - enum: [1, 2, 4] + + port: + type: object + description: + Input port node, as described in video-interfaces.txt. + + properties: + endpoint: + type: object + + properties: + clock-lanes: + items: + - const: 0 + + data-lanes: + description: + Lane reordering is not supported, items shall be in order, + starting at 1. + allOf: + - $ref: "/schemas/types.yaml#/definitions/uint32-array" + - maxItems: 1 + items: + minItems: 1 + maxItems: 4 + items: + - const: 1 + - const: 2 + - const: 3 + - const: 4 + + lane-polarities: + description: + Lane inversion is not supported. If the property is specified, it + shall contain all 0's. + allOf: + - $ref: "/schemas/types.yaml#/definitions/uint32-array" + - maxItems: 1 + items: + minItems: 2 + maxItems: 5 + items: + - const: 0 + - const: 0 + - const: 0 + - const: 0 + - const: 0 + + remote-endpoint: true + + required: + - data-lanes + - remote-endpoint + + additionalProperties: false + + required: + - endpoint + + additionalProperties: false + +required: + - compatible + - reg + - interrupts + - clocks + - clock-names + - power-domains + - brcm,num-data-lanes + - port + +additionalProperties: false + +examples: + - | + #include + #include + #include + + csi@7e801000 { + compatible = "brcm,bcm2835-unicam"; + reg = <0x7e801000 0x800>, + <0x7e802004 0x4>; + interrupts = <2 7>; + clocks = <&clocks BCM2835_CLOCK_CAM1>; + clock-names = "lp"; + power-domains = <&power RPI_POWER_DOMAIN_UNICAM1>; + brcm,num-data-lanes = <4>; + + port { + csi1_ep: endpoint { + remote-endpoint = <&imx219_0>; + data-lanes = <1 2>; + }; + }; + }; +... From patchwork Tue Nov 10 17:40:36 2020 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Jacopo Mondi X-Patchwork-Id: 323307 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-12.7 required=3.0 tests=BAYES_00, HEADER_FROM_DIFFERENT_DOMAINS, INCLUDES_PATCH, MAILING_LIST_MULTI, SIGNED_OFF_BY, SPF_HELO_NONE,SPF_PASS,URIBL_BLOCKED,USER_AGENT_GIT autolearn=ham autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id 50178C4741F for ; Tue, 10 Nov 2020 17:40:58 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 0202F20825 for ; Tue, 10 Nov 2020 17:40:57 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1730853AbgKJRk5 (ORCPT ); Tue, 10 Nov 2020 12:40:57 -0500 Received: from relay9-d.mail.gandi.net ([217.70.183.199]:40835 "EHLO relay9-d.mail.gandi.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1730796AbgKJRk5 (ORCPT ); Tue, 10 Nov 2020 12:40:57 -0500 X-Originating-IP: 93.34.118.233 Received: from uno.lan (93-34-118-233.ip49.fastwebnet.it [93.34.118.233]) (Authenticated sender: jacopo@jmondi.org) by relay9-d.mail.gandi.net (Postfix) with ESMTPSA id 87C83FF80B; Tue, 10 Nov 2020 17:40:53 +0000 (UTC) From: Jacopo Mondi To: linux-media@vger.kernel.org Cc: Jacopo Mondi , naush@raspberrypi.com, dave.stevenson@raspberrypi.com, laurent.pinchart@ideasonboard.com, kieran.bingham@ideasonboard.com, niklas.soderlund@ragnatech.se, dafna.hirschfeld@collabora.com, hverkuil@xs4all.nl, sakari.ailus@iki.fi, nsaenzjulienne@suse.de, mchehab+huawei@kernel.org Subject: [PATCH v4 5/5] media: bcm2835-unicam: Add TODO file Date: Tue, 10 Nov 2020 18:40:36 +0100 Message-Id: <20201110174036.220883-6-jacopo@jmondi.org> X-Mailer: git-send-email 2.29.1 In-Reply-To: <20201110174036.220883-1-jacopo@jmondi.org> References: <20201110174036.220883-1-jacopo@jmondi.org> MIME-Version: 1.0 Precedence: bulk List-ID: X-Mailing-List: linux-media@vger.kernel.org The bcm2835-unicam driver is currently in staging mainly for two reasons: - Handling of CSI-2 embedded data - Usage of both media controller API and subdev kAPI Provide a more detailed description of the currently on-going design discussions in the associated TODO file. Signed-off-by: Jacopo Mondi --- drivers/staging/media/bcm2835-unicam/TODO | 37 +++++++++++++++++++++++ 1 file changed, 37 insertions(+) create mode 100644 drivers/staging/media/bcm2835-unicam/TODO diff --git a/drivers/staging/media/bcm2835-unicam/TODO b/drivers/staging/media/bcm2835-unicam/TODO new file mode 100644 index 0000000000000..c7840872eea4c --- /dev/null +++ b/drivers/staging/media/bcm2835-unicam/TODO @@ -0,0 +1,37 @@ +BCM2835 Unicam driver TODO list +=============================== + +The unicam driver could be considered ready to be moved out of the staging +directory in terms of code quality and expected functionalities. + +However there currently are two design issues that suggest the driver is +better kept in staging for the time being. + +CSI-2 Embedded data support: +---------------------------- + +The RaspberryPi camera stack and camera applications rely on the availability of +the sensor produced CSI-2 embedded data, whose support is currently not +finalized in mainline Linux. + +The driver conditionally registers an additional video device node +'unicam-embedded' with a single sink pad which connects to the sensor +sub-device source pad #1 to expose ancillary data. + +Currently none of the mainline sensor drivers register more than a single pad, +and consequentially no embedded data from the sensor are exposed to userspace. + +The current implementation is then subject to changes depending on how support +for CSI-2 embedded data gets finalized in Linux. + +Media controller support: +------------------------- + +Due to compatibility reasons with the existing RaspberryPi software ecosystem +the unicam driver implements the media controller interface to allow the +enumeration of the connected entities but handles the configuration of the +sensor sub-device using the v4l2-subdev kAPI instead of delegating that to +user-space. + +Discussions are on-going on how this should be better handled (driver option, +KConfig option etc etc).