From patchwork Mon May 23 21:23:23 2022 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Doug Anderson X-Patchwork-Id: 12859493 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 BDF86C433EF for ; Mon, 23 May 2022 21:23:34 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S231657AbiEWVXd (ORCPT ); Mon, 23 May 2022 17:23:33 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:43016 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S231381AbiEWVXc (ORCPT ); Mon, 23 May 2022 17:23:32 -0400 Received: from mail-pj1-x102f.google.com (mail-pj1-x102f.google.com [IPv6:2607:f8b0:4864:20::102f]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id A4AFB6FD22 for ; Mon, 23 May 2022 14:23:30 -0700 (PDT) Received: by mail-pj1-x102f.google.com with SMTP id v5-20020a17090a7c0500b001df84fa82f8so425765pjf.5 for ; Mon, 23 May 2022 14:23:30 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=chromium.org; s=google; h=from:to:cc:subject:date:message-id:mime-version :content-transfer-encoding; bh=sQAatZV5NnfoF9WuNNy+yRJv0Fno2wnlohfY6hxqcKo=; b=XLcg+FpMHpseQi+OkiMTv3/y5Vv/vzEzVgxLJ+voWj/1pzB6aG7oqja0fl9mgXWEau /2qYZnBjmZlNRWo3A2g+fAn7NkZmGB27uYFEkwnz4yFCGUnABEj3cxu9deWc3N0kONtL PPuY1IXpFEwLrIu3HjNlgw6PwqPgXYvD7yiZM= X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20210112; h=x-gm-message-state:from:to:cc:subject:date:message-id:mime-version :content-transfer-encoding; bh=sQAatZV5NnfoF9WuNNy+yRJv0Fno2wnlohfY6hxqcKo=; b=XEruVE+ywkIMy11BDxiYQ2TAiAGY526sqTb311iiUPjcaNK8aNqiPY8jCe+q59G2Qy B59Ut8fFA62kHpNqHRuxTRvzoiLizqBIZ2VKFClEilaugKH5nw5GEfOaMH0M1/bFQ7re k1dABGV17QP5UyGDloE4d+P/Fle9V99zyqH13xSFyCXhq6C28YLu+nZQ/zqpDpP3QoK3 W6pxGY7PDjNhaZcGc622eOQclYN2PSM9utwDGi+HIV2NGU2wISv1f6Lt1sCQMwz95917 HDD1kt9kWeftHwcbu4HVR+/KivqE/7ZaVLkJzZlzXbkTVQ3whKuIC43CT8MyJ720cYwD CWlw== X-Gm-Message-State: AOAM533sxzaa0ld4Q4w9oOIazngo0PPmdwAbdais+bBjZ2uMXidubivE tSXMe0c0cEa/+6IkN4N3wyUzSA== X-Google-Smtp-Source: ABdhPJwUu257XWos/EKzre0r3S5qICXanQlox2IWgIPD8747Pymaf7700D7Rm+fp0UynkANX6FUT6Q== X-Received: by 2002:a17:90b:4d8b:b0:1dc:aebe:4c8b with SMTP id oj11-20020a17090b4d8b00b001dcaebe4c8bmr970265pjb.145.1653341010131; Mon, 23 May 2022 14:23:30 -0700 (PDT) Received: from tictac2.mtv.corp.google.com ([2620:15c:202:201:64b0:b6b9:c0f3:1cc8]) by smtp.gmail.com with ESMTPSA id x2-20020a170902ec8200b0015e8d4eb234sm5545922plg.126.2022.05.23.14.23.28 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Mon, 23 May 2022 14:23:29 -0700 (PDT) From: Douglas Anderson To: Jiri Kosina , Benjamin Tissoires , Dmitry Torokhov , Rob Herring , Krzysztof Kozlowski Cc: linux-input@vger.kernel.org, devicetree@vger.kernel.org, swboyd@chromium.org, mka@chromium.org, Douglas Anderson , linux-kernel@vger.kernel.org Subject: [PATCH v2 1/2] dt-bindings: HID: i2c-hid: elan: Introduce bindings for Elan eKTH6915 Date: Mon, 23 May 2022 14:23:23 -0700 Message-Id: <20220523142257.v2.1.Iedc61f9ef220a89af6a031200a7850a27a440134@changeid> X-Mailer: git-send-email 2.36.1.124.g0e6072fb45-goog MIME-Version: 1.0 Precedence: bulk List-ID: X-Mailing-List: linux-input@vger.kernel.org Like many i2c-hid touchscreen controllers, the Elan eKTH6915 controller has a reset gpio. For the Goodix GT7375P touchscreen the decision was to add a new binding rather than trying to add a new GPIO to the existing i2c-hid binding. We'll follow the lead and do it here, too. SIDE NOTE: the Elan eKTH6915 is a touchscreen _controller_ that's included as a part on some touchscreens. The reset line isn't truly necessary for the functioning of the touchscreen, so it's possible that some designs won't have it hooked up and will just guarantee the power sequencing requirements with RLC circuits. Thus, we'll mark the reset gpio as optional. Note that if the reset GPIO isn't used there's actually no true need to use the "elan,ekth6915" compatible instead of the "hid-over-i2c" on Linux. However: - Officially using just "hid-over-i2c" for this device violates the existing "hid-over-i2c" bindings. The bindings say that you're not supposed to use "post-power-on-delay-ms" without specifying a more specific compatible. Currently the Linux driver doesn't enforce this, but it violates the bindings to just use "hid-over-i2c". ...and if you're going to add a more specific compatible anyway, might as well do it right. - Using this compatible means we don't need to specify "hid-descr-addr" since it's inferred from the compatible. - Using this compatible means that the regulator names match the names on the Elan datasheet (vcc33 / vccio) vs the generic hid-over-i2c (vdd / vddl). Signed-off-by: Douglas Anderson Reviewed-by: Dmitry Torokhov Reviewed-by: Rob Herring --- (no changes since v1) .../bindings/input/elan,ekth6915.yaml | 65 +++++++++++++++++++ 1 file changed, 65 insertions(+) create mode 100644 Documentation/devicetree/bindings/input/elan,ekth6915.yaml diff --git a/Documentation/devicetree/bindings/input/elan,ekth6915.yaml b/Documentation/devicetree/bindings/input/elan,ekth6915.yaml new file mode 100644 index 000000000000..05e6f2df604c --- /dev/null +++ b/Documentation/devicetree/bindings/input/elan,ekth6915.yaml @@ -0,0 +1,65 @@ +# SPDX-License-Identifier: (GPL-2.0-only OR BSD-2-Clause) +%YAML 1.2 +--- +$id: http://devicetree.org/schemas/input/elan,ekth6915.yaml# +$schema: http://devicetree.org/meta-schemas/core.yaml# + +title: Elan eKTH6915 touchscreen controller + +maintainers: + - Douglas Anderson + +description: + Supports the Elan eKTH6915 touchscreen controller. + This touchscreen controller uses the i2c-hid protocol with a reset GPIO. + +properties: + compatible: + items: + - const: elan,ekth6915 + + reg: + const: 0x10 + + interrupts: + maxItems: 1 + + reset-gpios: + description: Reset GPIO; not all touchscreens using eKTH6915 hook this up. + + vcc33-supply: + description: The 3.3V supply to the touchscreen. + + vccio-supply: + description: + The IO supply to the touchscreen. Need not be specified if this is the + same as the 3.3V supply. + +required: + - compatible + - reg + - interrupts + - vcc33-supply + +additionalProperties: false + +examples: + - | + #include + #include + + i2c { + #address-cells = <1>; + #size-cells = <0>; + + ap_ts: touchscreen@10 { + compatible = "elan,ekth6915"; + reg = <0x10>; + + interrupt-parent = <&tlmm>; + interrupts = <9 IRQ_TYPE_LEVEL_LOW>; + + reset-gpios = <&tlmm 8 GPIO_ACTIVE_LOW>; + vcc33-supply = <&pp3300_ts>; + }; + };