From patchwork Wed May 19 09:42:18 2021 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Oleksij Rempel X-Patchwork-Id: 442689 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=-21.7 required=3.0 tests=BAYES_00, HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_CR_TRAILER,INCLUDES_PATCH, MAILING_LIST_MULTI, MENTIONS_GIT_HOSTING, SPF_HELO_NONE, SPF_PASS, URIBL_BLOCKED, USER_AGENT_GIT autolearn=unavailable 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 40B96C43617 for ; Wed, 19 May 2021 09:42:38 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 27AFE611BF for ; Wed, 19 May 2021 09:42:38 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1344773AbhESJn4 (ORCPT ); Wed, 19 May 2021 05:43:56 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:60410 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1345693AbhESJnx (ORCPT ); Wed, 19 May 2021 05:43:53 -0400 Received: from metis.ext.pengutronix.de (metis.ext.pengutronix.de [IPv6:2001:67c:670:201:290:27ff:fe1d:cc33]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 5DD9EC06138C for ; Wed, 19 May 2021 02:42:33 -0700 (PDT) Received: from dude.hi.pengutronix.de ([2001:67c:670:100:1d::7]) by metis.ext.pengutronix.de with esmtps (TLS1.3:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.92) (envelope-from ) id 1ljIie-0002Bi-GO; Wed, 19 May 2021 11:42:24 +0200 Received: from ore by dude.hi.pengutronix.de with local (Exim 4.92) (envelope-from ) id 1ljIic-0007OQ-Od; Wed, 19 May 2021 11:42:22 +0200 From: Oleksij Rempel To: Dmitry Torokhov , Rob Herring , Jonathan Cameron Cc: Oleksij Rempel , kernel@pengutronix.de, linux-kernel@vger.kernel.org, linux-input@vger.kernel.org, David Jander , devicetree@vger.kernel.org Subject: [PATCH v4 2/5] dt-bindings: touchscreen: Convert resistive-adc-touch binding to json schema Date: Wed, 19 May 2021 11:42:18 +0200 Message-Id: <20210519094221.27792-3-o.rempel@pengutronix.de> X-Mailer: git-send-email 2.29.2 In-Reply-To: <20210519094221.27792-1-o.rempel@pengutronix.de> References: <20210519094221.27792-1-o.rempel@pengutronix.de> MIME-Version: 1.0 X-SA-Exim-Connect-IP: 2001:67c:670:100:1d::7 X-SA-Exim-Mail-From: ore@pengutronix.de X-SA-Exim-Scanned: No (on metis.ext.pengutronix.de); SAEximRunCond expanded to false X-PTX-Original-Recipient: devicetree@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: devicetree@vger.kernel.org Convert the resistive-adc-touch binding to DT schema format using json-schema. Signed-off-by: Oleksij Rempel Reviewed-by: Rob Herring --- .../input/touchscreen/resistive-adc-touch.txt | 33 --------- .../touchscreen/resistive-adc-touch.yaml | 70 +++++++++++++++++++ 2 files changed, 70 insertions(+), 33 deletions(-) delete mode 100644 Documentation/devicetree/bindings/input/touchscreen/resistive-adc-touch.txt create mode 100644 Documentation/devicetree/bindings/input/touchscreen/resistive-adc-touch.yaml diff --git a/Documentation/devicetree/bindings/input/touchscreen/resistive-adc-touch.txt b/Documentation/devicetree/bindings/input/touchscreen/resistive-adc-touch.txt deleted file mode 100644 index af5223bb5bdd..000000000000 --- a/Documentation/devicetree/bindings/input/touchscreen/resistive-adc-touch.txt +++ /dev/null @@ -1,33 +0,0 @@ -Generic resistive touchscreen ADC - -Required properties: - - - compatible: must be "resistive-adc-touch" -The device must be connected to an ADC device that provides channels for -position measurement and optional pressure. -Refer to -https://github.com/devicetree-org/dt-schema/blob/master/schemas/iio/iio-consumer.yaml -for details - - - iio-channels: must have at least two channels connected to an ADC device. -These should correspond to the channels exposed by the ADC device and should -have the right index as the ADC device registers them. These channels -represent the relative position on the "x" and "y" axes. - - iio-channel-names: must have all the channels' names. Mandatory channels -are "x" and "y". - -Optional properties: - - iio-channels: The third channel named "pressure" is optional and can be -used if the ADC device also measures pressure besides position. -If this channel is missing, pressure will be ignored and the touchscreen -will only report position. - - iio-channel-names: optional channel named "pressure". - -Example: - - resistive_touch: resistive_touch { - compatible = "resistive-adc-touch"; - touchscreen-min-pressure = <50000>; - io-channels = <&adc 24>, <&adc 25>, <&adc 26>; - io-channel-names = "x", "y", "pressure"; - }; diff --git a/Documentation/devicetree/bindings/input/touchscreen/resistive-adc-touch.yaml b/Documentation/devicetree/bindings/input/touchscreen/resistive-adc-touch.yaml new file mode 100644 index 000000000000..38b4cbee9429 --- /dev/null +++ b/Documentation/devicetree/bindings/input/touchscreen/resistive-adc-touch.yaml @@ -0,0 +1,70 @@ +# SPDX-License-Identifier: (GPL-2.0 OR BSD-2-Clause) +%YAML 1.2 +--- +$id: http://devicetree.org/schemas/input/touchscreen/resistive-adc-touch.yaml# +$schema: http://devicetree.org/meta-schemas/core.yaml# + +title: Generic resistive touchscreen ADC + +maintainers: + - Oleksij Rempel + +description: | + Generic ADC based resistive touchscreen controller + The device must be connected to an ADC device that provides channels for + position measurement and optional pressure. + +allOf: + - $ref: touchscreen.yaml# + +properties: + compatible: + const: resistive-adc-touch + + io-channels: + minItems: 2 + items: + - description: x + - description: y + - description: pressure (optional) + + io-channel-names: + oneOf: + - items: + - enum: [x, y] + - enum: [x, y] + - items: + - enum: [x, y, pressure] + - enum: [x, y, pressure] + - enum: [x, y, pressure] + + touchscreen-size-x: true + touchscreen-size-y: true + touchscreen-fuzz-x: true + touchscreen-fuzz-y: true + touchscreen-inverted-x: true + touchscreen-inverted-y: true + touchscreen-swapped-x-y: true + touchscreen-min-pressure: true + +additionalProperties: false + +required: + - compatible + - io-channels + - io-channel-names + +examples: + - | + touchscreen { + compatible = "resistive-adc-touch"; + io-channels = <&adc 24>, <&adc 25>; + io-channel-names = "y", "x"; + }; + - | + touchscreen { + compatible = "resistive-adc-touch"; + touchscreen-min-pressure = <50000>; + io-channels = <&adc 24>, <&adc 25>, <&adc 26>; + io-channel-names = "y", "pressure", "x"; + }; From patchwork Wed May 19 09:42:20 2021 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Oleksij Rempel X-Patchwork-Id: 442691 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=-16.7 required=3.0 tests=BAYES_00, HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_CR_TRAILER,INCLUDES_PATCH, MAILING_LIST_MULTI, SPF_HELO_NONE, SPF_PASS, URIBL_BLOCKED, USER_AGENT_GIT autolearn=unavailable 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 10801C43461 for ; Wed, 19 May 2021 09:42:36 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id E42E3613C4 for ; Wed, 19 May 2021 09:42:35 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1345817AbhESJnx (ORCPT ); Wed, 19 May 2021 05:43:53 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:60396 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1345520AbhESJnw (ORCPT ); Wed, 19 May 2021 05:43:52 -0400 Received: from metis.ext.pengutronix.de (metis.ext.pengutronix.de [IPv6:2001:67c:670:201:290:27ff:fe1d:cc33]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id BB89DC061763 for ; Wed, 19 May 2021 02:42:32 -0700 (PDT) Received: from dude.hi.pengutronix.de ([2001:67c:670:100:1d::7]) by metis.ext.pengutronix.de with esmtps (TLS1.3:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.92) (envelope-from ) id 1ljIie-0002Bk-GX; Wed, 19 May 2021 11:42:24 +0200 Received: from ore by dude.hi.pengutronix.de with local (Exim 4.92) (envelope-from ) id 1ljIic-0007Ox-Qw; Wed, 19 May 2021 11:42:22 +0200 From: Oleksij Rempel To: Dmitry Torokhov , Rob Herring , Jonathan Cameron Cc: Oleksij Rempel , kernel@pengutronix.de, linux-kernel@vger.kernel.org, linux-input@vger.kernel.org, David Jander , devicetree@vger.kernel.org Subject: [PATCH v4 4/5] dt-bindings: touchscreen: resistive-adc-touch: add support for z1 and z2 channels Date: Wed, 19 May 2021 11:42:20 +0200 Message-Id: <20210519094221.27792-5-o.rempel@pengutronix.de> X-Mailer: git-send-email 2.29.2 In-Reply-To: <20210519094221.27792-1-o.rempel@pengutronix.de> References: <20210519094221.27792-1-o.rempel@pengutronix.de> MIME-Version: 1.0 X-SA-Exim-Connect-IP: 2001:67c:670:100:1d::7 X-SA-Exim-Mail-From: ore@pengutronix.de X-SA-Exim-Scanned: No (on metis.ext.pengutronix.de); SAEximRunCond expanded to false X-PTX-Original-Recipient: devicetree@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: devicetree@vger.kernel.org For pressure calculation based on plates resistance we need some additional properties: - z1 and z2 channels with additional measurements between plates - actual resistance of the touchscreen. Currently we use only X-resistance. Signed-off-by: Oleksij Rempel Reviewed-by: Rob Herring --- .../input/touchscreen/resistive-adc-touch.yaml | 16 ++++++++++++++++ 1 file changed, 16 insertions(+) diff --git a/Documentation/devicetree/bindings/input/touchscreen/resistive-adc-touch.yaml b/Documentation/devicetree/bindings/input/touchscreen/resistive-adc-touch.yaml index 38b4cbee9429..7fc22a403d48 100644 --- a/Documentation/devicetree/bindings/input/touchscreen/resistive-adc-touch.yaml +++ b/Documentation/devicetree/bindings/input/touchscreen/resistive-adc-touch.yaml @@ -27,6 +27,8 @@ properties: - description: x - description: y - description: pressure (optional) + - description: z1 (optional) + - description: z2 (optional) io-channel-names: oneOf: @@ -37,6 +39,11 @@ properties: - enum: [x, y, pressure] - enum: [x, y, pressure] - enum: [x, y, pressure] + - items: + - enum: [x, y, z1, z2] + - enum: [x, y, z1, z2] + - enum: [x, y, z1, z2] + - enum: [x, y, z1, z2] touchscreen-size-x: true touchscreen-size-y: true @@ -46,6 +53,7 @@ properties: touchscreen-inverted-y: true touchscreen-swapped-x-y: true touchscreen-min-pressure: true + touchscreen-x-plate-ohms: true additionalProperties: false @@ -68,3 +76,11 @@ examples: io-channels = <&adc 24>, <&adc 25>, <&adc 26>; io-channel-names = "y", "pressure", "x"; }; + - | + touchscreen { + compatible = "resistive-adc-touch"; + touchscreen-min-pressure = <50000>; + io-channels = <&adc 1>, <&adc 2>, <&adc 3>, <&adc 4>; + io-channel-names = "x", "z1", "z2", "y"; + touchscreen-x-plate-ohms = <800>; + }; From patchwork Wed May 19 09:42:21 2021 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Oleksij Rempel X-Patchwork-Id: 442690 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=-16.7 required=3.0 tests=BAYES_00, HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_CR_TRAILER,INCLUDES_PATCH, MAILING_LIST_MULTI, SPF_HELO_NONE, SPF_PASS, URIBL_BLOCKED, USER_AGENT_GIT autolearn=unavailable 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 2CD55C43603 for ; Wed, 19 May 2021 09:42:37 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 12643611BF for ; Wed, 19 May 2021 09:42:37 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1345690AbhESJnz (ORCPT ); Wed, 19 May 2021 05:43:55 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:60400 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1345675AbhESJnw (ORCPT ); Wed, 19 May 2021 05:43:52 -0400 Received: from metis.ext.pengutronix.de (metis.ext.pengutronix.de [IPv6:2001:67c:670:201:290:27ff:fe1d:cc33]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id D95AFC0613ED for ; Wed, 19 May 2021 02:42:32 -0700 (PDT) Received: from dude.hi.pengutronix.de ([2001:67c:670:100:1d::7]) by metis.ext.pengutronix.de with esmtps (TLS1.3:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.92) (envelope-from ) id 1ljIie-0002Bl-GP; Wed, 19 May 2021 11:42:24 +0200 Received: from ore by dude.hi.pengutronix.de with local (Exim 4.92) (envelope-from ) id 1ljIic-0007PI-S2; Wed, 19 May 2021 11:42:22 +0200 From: Oleksij Rempel To: Dmitry Torokhov , Rob Herring , Jonathan Cameron Cc: Oleksij Rempel , kernel@pengutronix.de, linux-kernel@vger.kernel.org, linux-input@vger.kernel.org, David Jander , devicetree@vger.kernel.org Subject: [PATCH v4 5/5] Input: resistive-adc-touch: add support for z1 and z2 channels Date: Wed, 19 May 2021 11:42:21 +0200 Message-Id: <20210519094221.27792-6-o.rempel@pengutronix.de> X-Mailer: git-send-email 2.29.2 In-Reply-To: <20210519094221.27792-1-o.rempel@pengutronix.de> References: <20210519094221.27792-1-o.rempel@pengutronix.de> MIME-Version: 1.0 X-SA-Exim-Connect-IP: 2001:67c:670:100:1d::7 X-SA-Exim-Mail-From: ore@pengutronix.de X-SA-Exim-Scanned: No (on metis.ext.pengutronix.de); SAEximRunCond expanded to false X-PTX-Original-Recipient: devicetree@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: devicetree@vger.kernel.org This patch adds support for the z1 and z2 channels. These are used to calculate the applied pressure. As there is no common order of the individual channels of a resistive touch ADC, support for io-channel-names is added (although the DT bindings stated the driver already supports these). Signed-off-by: Oleksij Rempel --- .../input/touchscreen/resistive-adc-touch.c | 142 ++++++++++++++++-- 1 file changed, 128 insertions(+), 14 deletions(-) diff --git a/drivers/input/touchscreen/resistive-adc-touch.c b/drivers/input/touchscreen/resistive-adc-touch.c index e50af30183f4..fa90005b7bc9 100644 --- a/drivers/input/touchscreen/resistive-adc-touch.c +++ b/drivers/input/touchscreen/resistive-adc-touch.c @@ -20,7 +20,18 @@ #define DRIVER_NAME "resistive-adc-touch" #define GRTS_DEFAULT_PRESSURE_MIN 50000 +#define GRTS_DEFAULT_PRESSURE_MAX 65535 #define GRTS_MAX_POS_MASK GENMASK(11, 0) +#define GRTS_MAX_CHANNELS 4 + +enum grts_ch_type { + GRTS_CH_NONE = 0, + GRTS_CH_X, + GRTS_CH_Y, + GRTS_CH_PRESSURE, + GRTS_CH_Z1, + GRTS_CH_Z2, +}; /** * struct grts_state - generic resistive touch screen information struct @@ -33,24 +44,61 @@ */ struct grts_state { u32 pressure_min; + u32 x_plate_ohms; bool pressure; struct iio_channel *iio_chans; struct iio_cb_buffer *iio_cb; struct input_dev *input; struct touchscreen_properties prop; + u8 ch[GRTS_MAX_CHANNELS]; }; static int grts_cb(const void *data, void *private) { const u16 *touch_info = data; struct grts_state *st = private; - unsigned int x, y, press = 0x0; + unsigned int x, y, press = 0, z1 = 0, z2; + unsigned int Rt, i; + + for (i = 0; i < ARRAY_SIZE(st->ch) && st->ch[i] != GRTS_CH_NONE; i++) { + switch (st->ch[i]) { + case GRTS_CH_X: + x = touch_info[i]; + break; + case GRTS_CH_Y: + y = touch_info[i]; + break; + case GRTS_CH_PRESSURE: + press = touch_info[i]; + break; + case GRTS_CH_Z1: + z1 = touch_info[i]; + break; + case GRTS_CH_Z2: + z2 = touch_info[i]; + break; + case GRTS_CH_NONE: + break; + } + } - /* channel data coming in buffer in the order below */ - x = touch_info[0]; - y = touch_info[1]; - if (st->pressure) - press = touch_info[2]; + if (z1) { + Rt = z2; + Rt -= z1; + Rt *= st->x_plate_ohms; + Rt = DIV_ROUND_CLOSEST(Rt, 16); + Rt *= x; + Rt /= z1; + Rt = DIV_ROUND_CLOSEST(Rt, 256); + /* + * On increased pressure the resistance (Rt) is decreasing + * so, convert values to make it looks as real pressure. + */ + if (Rt < GRTS_DEFAULT_PRESSURE_MAX) + press = GRTS_DEFAULT_PRESSURE_MAX - Rt; + else + press = 0; + } if ((!x && !y) || (st->pressure && (press < st->pressure_min))) { /* report end of touch */ @@ -94,12 +142,77 @@ static void grts_disable(void *data) iio_channel_release_all_cb(data); } +static int grts_get_properties(struct grts_state *st, struct device *dev) +{ + int idx, error; + + idx = device_property_match_string(dev, "io-channel-names", "x"); + if (idx < 0) + return idx; + + if (idx >= ARRAY_SIZE(st->ch)) + return -EOVERFLOW; + + st->ch[idx] = GRTS_CH_X; + + idx = device_property_match_string(dev, "io-channel-names", "y"); + if (idx < 0) + return idx; + + if (idx >= ARRAY_SIZE(st->ch)) + return -EOVERFLOW; + + st->ch[idx] = GRTS_CH_Y; + + /* pressure is optional */ + idx = device_property_match_string(dev, "io-channel-names", "pressure"); + if (idx >= 0) { + if (idx >= ARRAY_SIZE(st->ch)) + return -EOVERFLOW; + + st->ch[idx] = GRTS_CH_PRESSURE; + st->pressure = true; + + return 0; + } + + /* if no pressure is defined, try optional z1 + z2 */ + idx = device_property_match_string(dev, "io-channel-names", "z1"); + if (idx < 0) + return 0; + + if (idx >= ARRAY_SIZE(st->ch)) + return -EOVERFLOW; + + st->ch[idx] = GRTS_CH_Z1; + + /* if z1 is provided z2 is not optional */ + idx = device_property_match_string(dev, "io-channel-names", "z2"); + if (idx < 0) + return idx; + + if (idx >= ARRAY_SIZE(st->ch)) + return -EOVERFLOW; + + st->ch[idx] = GRTS_CH_Z2; + st->pressure = true; + + error = device_property_read_u32(dev, + "touchscreen-x-plate-ohms", + &st->x_plate_ohms); + if (error) { + dev_err(dev, "can't get touchscreen-x-plate-ohms property\n"); + return error; + } + + return 0; +} + static int grts_probe(struct platform_device *pdev) { struct grts_state *st; struct input_dev *input; struct device *dev = &pdev->dev; - struct iio_channel *chan; int error; st = devm_kzalloc(dev, sizeof(struct grts_state), GFP_KERNEL); @@ -115,12 +228,13 @@ static int grts_probe(struct platform_device *pdev) return error; } - chan = &st->iio_chans[0]; - st->pressure = false; - while (chan && chan->indio_dev) { - if (!strcmp(chan->channel->datasheet_name, "pressure")) - st->pressure = true; - chan++; + if (!device_property_present(dev, "io-channel-names")) + return -ENODEV; + + error = grts_get_properties(st, dev); + if (error) { + dev_err(dev, "Failed to parse properties\n"); + return error; } if (st->pressure) { @@ -148,7 +262,7 @@ static int grts_probe(struct platform_device *pdev) input_set_abs_params(input, ABS_Y, 0, GRTS_MAX_POS_MASK - 1, 0, 0); if (st->pressure) input_set_abs_params(input, ABS_PRESSURE, st->pressure_min, - 0xffff, 0, 0); + GRTS_DEFAULT_PRESSURE_MAX, 0, 0); input_set_capability(input, EV_KEY, BTN_TOUCH);