From patchwork Thu May 19 23:00:02 2022 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Doug Anderson X-Patchwork-Id: 574714 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 03713C433F5 for ; Thu, 19 May 2022 23:01:06 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S243471AbiESXBF (ORCPT ); Thu, 19 May 2022 19:01:05 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:57568 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S241693AbiESXA6 (ORCPT ); Thu, 19 May 2022 19:00:58 -0400 Received: from mail-pj1-x102a.google.com (mail-pj1-x102a.google.com [IPv6:2607:f8b0:4864:20::102a]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id A8A1FFD14 for ; Thu, 19 May 2022 16:00:55 -0700 (PDT) Received: by mail-pj1-x102a.google.com with SMTP id nk9-20020a17090b194900b001df2fcdc165so10027407pjb.0 for ; Thu, 19 May 2022 16:00:55 -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=/+cnG0T1VfIcJDi4Tnrthnwsto5lgJAgXz/DN8hILeM=; b=E9ICPWOHq0JDDEynKw8oMU09qUbnljwf2UPOKuvme7k2m0oT7juy2tMyXCboV6z0Lh 9sycljyk3NTft1DtA3PpNilaiobcApb+u6c2Qk4y2hu8ia/1wHl4muP/PDNNaJjK9m/4 IK0ZSFu8FZ5vG+vqOMAswOwCk+TcIYUkKesBQ= 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=/+cnG0T1VfIcJDi4Tnrthnwsto5lgJAgXz/DN8hILeM=; b=f6DMMDumYP1vMCvGGUggfmlHv6Nsqt/Ek2ylCFn9Vr+YL1q+XjSV/W/Usf8CUdbDSZ Nr7ISgeqysyC1um+tl2zqb8FXMRUpm1mKAy40P/jearNSmx77izf4EkwvOexSwc/Ci3G HWMW1oQlW6QGutxja4WxMOk5iThSpv9odTgBf4derMjll69mN5MNzJg40vVu1CewW+0X hyGRKmfiuextb7gwxZUYGXNzxpkRv/642v9OsjT+NO/bNl2sZXAGjKr2oeE+O4QcyikJ HtsQkx+ye6RZsvtP7yt0e/Ic5fpNH/pq6Yp/4gHAbWy/BfSwmpdB3gJ2xK5JJ6xIe0cg u6UA== X-Gm-Message-State: AOAM533c+2J16hfILCfp22mAfAinVJr7OuMvAcLUPSrhqJXCZdx0yziL 8HQL3/o4XZjPlpa0doL2CTSi6g== X-Google-Smtp-Source: ABdhPJw+ZRz4Jko72uPDZg2ZBv9BBdBcNFqM9VVfrbGvBZTPeeJB4aIvFwTEqu0JM4pnp3rKOYazRA== X-Received: by 2002:a17:90a:9311:b0:1dc:8d06:eb1b with SMTP id p17-20020a17090a931100b001dc8d06eb1bmr7490101pjo.41.1653001255156; Thu, 19 May 2022 16:00:55 -0700 (PDT) Received: from tictac2.mtv.corp.google.com ([2620:15c:202:201:e45f:1f3c:299b:4d86]) by smtp.gmail.com with ESMTPSA id m10-20020a056a00080a00b0050dc762819csm202411pfk.118.2022.05.19.16.00.54 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Thu, 19 May 2022 16:00:54 -0700 (PDT) From: Douglas Anderson To: Jiri Kosina , Benjamin Tissoires , Dmitry Torokhov , Rob Herring , Krzysztof Kozlowski Cc: swboyd@chromium.org, linux-input@vger.kernel.org, mka@chromium.org, devicetree@vger.kernel.org, Douglas Anderson , linux-kernel@vger.kernel.org Subject: [PATCH 1/2] dt-bindings: HID: i2c-hid: elan: Introduce bindings for Elan eKTH6915 Date: Thu, 19 May 2022 16:00:02 -0700 Message-Id: <20220519155925.1.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 --- .../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>; + }; + };