From patchwork Fri Jan 31 02:34:32 2020 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Chris Packham X-Patchwork-Id: 11359027 Return-Path: Received: from mail.kernel.org (pdx-korg-mail-1.web.codeaurora.org [172.30.200.123]) by pdx-korg-patchwork-2.web.codeaurora.org (Postfix) with ESMTP id 9F59114D5 for ; Fri, 31 Jan 2020 02:35:11 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 7358F206F0 for ; Fri, 31 Jan 2020 02:35:11 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (2048-bit key) header.d=alliedtelesis.co.nz header.i=@alliedtelesis.co.nz header.b="FuaxnXUY" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1727865AbgAaCeq (ORCPT ); Thu, 30 Jan 2020 21:34:46 -0500 Received: from gate2.alliedtelesis.co.nz ([202.36.163.20]:49090 "EHLO gate2.alliedtelesis.co.nz" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1727749AbgAaCeq (ORCPT ); Thu, 30 Jan 2020 21:34:46 -0500 Received: from mmarshal3.atlnz.lc (mmarshal3.atlnz.lc [10.32.18.43]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (Client did not present a certificate) by gate2.alliedtelesis.co.nz (Postfix) with ESMTPS id 1C9138365B; Fri, 31 Jan 2020 15:34:41 +1300 (NZDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=alliedtelesis.co.nz; s=mail181024; t=1580438081; bh=6tDJYJw6qyBxE5gbUdGqb3erz1PiKAMuHxH5IXgdldk=; h=From:To:Cc:Subject:Date:In-Reply-To:References; b=FuaxnXUY5/qpeLbWswkfNIKKSZuUjBu12k6kZSbWGXnRys0RHIODHz/1Vdjh3zq/W DKbhc3QuGFoM976BpBHIKn43jqNJKuozpFeFSeTifv796Yb+PTAkHMPfQSo2tnncFy HaDKiJtlvXnE005mk1/83nip5StliLq5kjTKAHj5qMO3vq3u5Qj5wwzyjexR8Mtd81 m/vwC+DRLXBWagapbxBa0v2QxuG7R9mEgVuQOtUB3WyV5XujXvDOzpC1XvMvJ/KKxz VqRBNqHTUhqyRPaBjATFSv5qJ8eVM1smShjSdXnhfjFeGUnwY8+AlX3qpvTwiuI0Gt eGMwwDHYvJUxw== Received: from smtp (Not Verified[10.32.16.33]) by mmarshal3.atlnz.lc with Trustwave SEG (v7,5,8,10121) id ; Fri, 31 Jan 2020 15:34:41 +1300 Received: from chrisp-dl.ws.atlnz.lc (chrisp-dl.ws.atlnz.lc [10.33.22.20]) by smtp (Postfix) with ESMTP id C501413EED4; Fri, 31 Jan 2020 15:34:40 +1300 (NZDT) Received: by chrisp-dl.ws.atlnz.lc (Postfix, from userid 1030) id EACDC280071; Fri, 31 Jan 2020 15:34:40 +1300 (NZDT) From: Chris Packham To: broonie@kernel.org, robh+dt@kernel.org, mark.rutland@arm.com, Andy Shevchenko Cc: linux-spi@vger.kernel.org, devicetree@vger.kernel.org, linux-kernel@vger.kernel.org, Chris Packham Subject: [PATCH v4 1/2] dt-bindings: spi: Document binding for generic SPI multiplexer Date: Fri, 31 Jan 2020 15:34:32 +1300 Message-Id: <20200131023433.12133-2-chris.packham@alliedtelesis.co.nz> X-Mailer: git-send-email 2.25.0 In-Reply-To: <20200131023433.12133-1-chris.packham@alliedtelesis.co.nz> References: <20200131023433.12133-1-chris.packham@alliedtelesis.co.nz> MIME-Version: 1.0 x-atlnz-ls: pat Sender: linux-spi-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-spi@vger.kernel.org Add binding documentation for the spi-mux driver. This allows a generic multiplexer to be used to provide access to multiple SPI devices. Signed-off-by: Chris Packham Reviewed-by: Rob Herring --- Notes: Changes in v3: - make dt_binding_check clean (properly this time) Changes in v2: - update license - make dt_binding_check clean .../devicetree/bindings/spi/spi-mux.yaml | 89 +++++++++++++++++++ 1 file changed, 89 insertions(+) create mode 100644 Documentation/devicetree/bindings/spi/spi-mux.yaml diff --git a/Documentation/devicetree/bindings/spi/spi-mux.yaml b/Documentation/devicetree/bindings/spi/spi-mux.yaml new file mode 100644 index 000000000000..0ae692dc28b5 --- /dev/null +++ b/Documentation/devicetree/bindings/spi/spi-mux.yaml @@ -0,0 +1,89 @@ +# SPDX-License-Identifier: (GPL-2.0 OR BSD-2-Clause) +%YAML 1.2 +--- +$id: http://devicetree.org/schemas/spi/spi-mux.yaml# +$schema: http://devicetree.org/meta-schemas/core.yaml# + +title: Generic SPI Multiplexer + +description: | + This binding describes a SPI bus multiplexer to route the SPI chip select + signals. This can be used when you need more devices than the SPI controller + has chip selects available. An example setup is shown in ASCII art; the actual + setting of the multiplexer to a channel needs to be done by a specific SPI mux + driver. + + MOSI /--------------------------------+--------+--------+--------\ + MISO |/------------------------------+|-------+|-------+|-------\| + SCL ||/----------------------------+||------+||------+||------\|| + ||| ||| ||| ||| ||| + +------------+ ||| ||| ||| ||| + | SoC ||| | +-+++-+ +-+++-+ +-+++-+ +-+++-+ + | ||| | | dev | | dev | | dev | | dev | + | +--+++-+ | CS-X +------+\ +--+--+ +--+--+ +--+--+ +--+--+ + | | SPI +-|-------+ Mux |\\ CS-0 | | | | + | +------+ | +--+---+\\\-------/ CS-1 | | | + | | | \\\----------------/ CS-2 | | + | +------+ | | \\-------------------------/ CS-3 | + | | ? +-|----------/ \----------------------------------/ + | +------+ | + +------------+ + +allOf: + - $ref: "/schemas/spi/spi-controller.yaml#" + +maintainers: + - Chris Packham + +properties: + compatible: + const: spi-mux + + mux-controls: + maxItems: 1 + +required: + - compatible + - reg + - spi-max-frequency + - mux-controls + +examples: + - | + #include + mux: mux-controller { + compatible = "gpio-mux"; + #mux-control-cells = <0>; + + mux-gpios = <&gpio0 3 GPIO_ACTIVE_HIGH>; + }; + + spi { + #address-cells = <1>; + #size-cells = <0>; + spi@0 { + compatible = "spi-mux"; + reg = <0>; + #address-cells = <1>; + #size-cells = <0>; + spi-max-frequency = <100000000>; + + mux-controls = <&mux>; + + spi-flash@0 { + compatible = "jedec,spi-nor"; + reg = <0>; + #address-cells = <1>; + #size-cells = <0>; + spi-max-frequency = <40000000>; + }; + + spi-device@1 { + compatible = "lineartechnology,ltc2488"; + reg = <1>; + #address-cells = <1>; + #size-cells = <0>; + spi-max-frequency = <10000000>; + }; + }; + };