From mboxrd@z Thu Jan 1 00:00:00 1970 From: =?UTF-8?q?Uwe=20Kleine-K=C3=B6nig?= Subject: [PATCH v4] Input: rotary_encoder - support binary encoding of states Date: Tue, 19 Jul 2016 21:38:39 +0200 Message-ID: <1468957119-16458-1-git-send-email-u.kleine-koenig@pengutronix.de> Mime-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: QUOTED-PRINTABLE Return-path: Received: from metis.ext.4.pengutronix.de ([92.198.50.35]:53467 "EHLO metis.ext.4.pengutronix.de" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751607AbcGSTjU (ORCPT ); Tue, 19 Jul 2016 15:39:20 -0400 Sender: linux-input-owner@vger.kernel.org List-Id: linux-input@vger.kernel.org To: linux-input@vger.kernel.org, devicetree@vger.kernel.org, Dmitry Torokhov , Rob Herring Cc: kernel@pengutronix.de It's not advisable to use this encoding, but to support existing device= s add support for this to the driver. Signed-off-by: Uwe Kleine-K=C3=B6nig --- Notes: Changes since (implicit) v1, sent with Message-Id: 1458680914-4533-1-git-send-email-u.kleine-koenig p= engutronix.de =20 - switch format of dt properties to use strings =20 Changes since v2, sent with Message-Id: 1458806232-22403-1-git-send-email-u.kleine-koenig = pengutronix.de =20 - be more strict about parsing the encoding string =20 Changes since v3, sent with Message-Id: 1460055528-13814-1-git-send-email-u.kleine-koenig@pengu= tronix.de =20 - use device_property_match_string to parse device tree as request= ed by Rob Herring. .../devicetree/bindings/input/rotary-encoder.txt | 4 ++++ drivers/input/misc/rotary_encoder.c | 23 ++++++++++++++= +++++++- 2 files changed, 26 insertions(+), 1 deletion(-) diff --git a/Documentation/devicetree/bindings/input/rotary-encoder.txt= b/Documentation/devicetree/bindings/input/rotary-encoder.txt index 6c9f0c8a846c..e85ce3dea480 100644 --- a/Documentation/devicetree/bindings/input/rotary-encoder.txt +++ b/Documentation/devicetree/bindings/input/rotary-encoder.txt @@ -20,6 +20,8 @@ Optional properties: 2: Half-period mode 4: Quarter-period mode - wakeup-source: Boolean, rotary encoder can wake up the system. +- rotary-encoder,encoding: String, the method used to encode steps. + Supported are "gray" (the default and more common) and "binary". =20 Deprecated properties: - rotary-encoder,half-period: Makes the driver work on half-period mod= e. @@ -34,6 +36,7 @@ Example: compatible =3D "rotary-encoder"; gpios =3D <&gpio 19 1>, <&gpio 20 0>; /* GPIO19 is inverted */ linux,axis =3D <0>; /* REL_X */ + rotary-encoder,encoding =3D "gray"; rotary-encoder,relative-axis; }; =20 @@ -42,5 +45,6 @@ Example: gpios =3D <&gpio 21 0>, <&gpio 22 0>; linux,axis =3D <1>; /* ABS_Y */ rotary-encoder,steps =3D <24>; + rotary-encoder,encoding =3D "binary"; rotary-encoder,rollover; }; diff --git a/drivers/input/misc/rotary_encoder.c b/drivers/input/misc/r= otary_encoder.c index c7fc8d4fb080..1588aecafff7 100644 --- a/drivers/input/misc/rotary_encoder.c +++ b/drivers/input/misc/rotary_encoder.c @@ -28,6 +28,11 @@ =20 #define DRV_NAME "rotary-encoder" =20 +enum rotary_encoder_encoding { + ROTENC_GRAY, + ROTENC_BINARY, +}; + struct rotary_encoder { struct input_dev *input; =20 @@ -37,6 +42,7 @@ struct rotary_encoder { u32 axis; bool relative_axis; bool rollover; + enum rotary_encoder_encoding encoding; =20 unsigned int pos; =20 @@ -57,8 +63,9 @@ static unsigned int rotary_encoder_get_state(struct r= otary_encoder *encoder) =20 for (i =3D 0; i < encoder->gpios->ndescs; ++i) { int val =3D gpiod_get_value_cansleep(encoder->gpios->desc[i]); + /* convert from gray encoding to normal */ - if (ret & 1) + if (encoder->encoding =3D=3D ROTENC_GRAY && ret & 1) val =3D !val; =20 ret =3D ret << 1 | val; @@ -213,6 +220,20 @@ static int rotary_encoder_probe(struct platform_de= vice *pdev) encoder->rollover =3D device_property_read_bool(dev, "rotary-encoder,rollover"); =20 + if (!device_property_present(dev, "rotary-encoder,encoding") || + !device_property_match_string(dev, "rotary-encoder,encoding", + "gray")) { + dev_info(dev, "gray"); + encoder->encoding =3D ROTENC_GRAY; + } else if (!device_property_match_string(dev, "rotary-encoder,encodin= g", + "binary")) { + dev_info(dev, "binary"); + encoder->encoding =3D ROTENC_BINARY; + } else { + dev_err(dev, "unknown encoding setting\n"); + return -EINVAL; + } + device_property_read_u32(dev, "linux,axis", &encoder->axis); encoder->relative_axis =3D device_property_read_bool(dev, "rotary-encoder,relative-axis"); --=20 2.8.1 -- To unsubscribe from this list: send the line "unsubscribe linux-input" = in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html