From patchwork Wed Oct 17 12:51:10 2018 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 8bit X-Patchwork-Submitter: Richard Leitner X-Patchwork-Id: 10645833 Return-Path: Received: from mail.wl.linuxfoundation.org (pdx-wl-mail.web.codeaurora.org [172.30.200.125]) by pdx-korg-patchwork-2.web.codeaurora.org (Postfix) with ESMTP id 58864181D for ; Wed, 17 Oct 2018 16:07:56 +0000 (UTC) Received: from mail.wl.linuxfoundation.org (localhost [127.0.0.1]) by mail.wl.linuxfoundation.org (Postfix) with ESMTP id 4825728733 for ; Wed, 17 Oct 2018 16:07:56 +0000 (UTC) Received: by mail.wl.linuxfoundation.org (Postfix, from userid 486) id 3CAB32872F; Wed, 17 Oct 2018 16:07:56 +0000 (UTC) X-Spam-Checker-Version: SpamAssassin 3.3.1 (2010-03-16) on pdx-wl-mail.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-6.3 required=2.0 tests=BAYES_00,DATE_IN_PAST_03_06, MAILING_LIST_MULTI,RCVD_IN_DNSWL_HI autolearn=ham version=3.3.1 Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.wl.linuxfoundation.org (Postfix) with ESMTP id CE3C028724 for ; Wed, 17 Oct 2018 16:07:55 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1727596AbeJRAES (ORCPT ); Wed, 17 Oct 2018 20:04:18 -0400 Received: from mail1.skidata.com ([91.230.2.99]:30719 "EHLO mail1.skidata.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1727014AbeJRAER (ORCPT ); Wed, 17 Oct 2018 20:04:17 -0400 X-IronPort-AV: E=Sophos;i="5.54,393,1534802400"; d="scan'208";a="12919542" From: Richard Leitner To: , , CC: , , , Richard Leitner Subject: [PATCH v2 2/8] Input: sx8654 - add reset-gpio support Date: Wed, 17 Oct 2018 14:51:10 +0200 Message-ID: <20181017125116.20077-3-richard.leitner@skidata.com> X-Mailer: git-send-email 2.11.0 In-Reply-To: <20181017125116.20077-1-richard.leitner@skidata.com> References: <20181017125116.20077-1-richard.leitner@skidata.com> MIME-Version: 1.0 X-Originating-IP: [192.168.111.252] X-ClientProxiedBy: sdex5srv.skidata.net (192.168.111.83) To sdex5srv.skidata.net (192.168.111.83) Sender: linux-input-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-input@vger.kernel.org X-Virus-Scanned: ClamAV using ClamSMTP The sx8654 features a NRST input which may be connected to a GPIO. Therefore add support for hard-resetting the sx8654 via this NRST. If the reset-gpio property is provided the sx8654 is resetted via NRST instead of the soft-reset via I2C. Signed-off-by: Richard Leitner --- drivers/input/touchscreen/sx8654.c | 40 +++++++++++++++++++++++++++++++++++--- 1 file changed, 37 insertions(+), 3 deletions(-) diff --git a/drivers/input/touchscreen/sx8654.c b/drivers/input/touchscreen/sx8654.c index ed29db3ec731..238f56b1581b 100644 --- a/drivers/input/touchscreen/sx8654.c +++ b/drivers/input/touchscreen/sx8654.c @@ -33,6 +33,8 @@ #include #include #include +#include +#include /* register addresses */ #define I2C_REG_TOUCH0 0x00 @@ -74,6 +76,7 @@ struct sx8654 { struct input_dev *input; struct i2c_client *client; + struct gpio_desc *gpio_reset; }; static irqreturn_t sx8654_irq(int irq, void *handle) @@ -124,6 +127,27 @@ static irqreturn_t sx8654_irq(int irq, void *handle) return IRQ_HANDLED; } +static int sx8654_reset(struct sx8654 *ts) +{ + int err; + + if (ts->gpio_reset) { + gpiod_set_value_cansleep(ts->gpio_reset, 1); + udelay(2); /* Tpulse > 1µs */ + gpiod_set_value_cansleep(ts->gpio_reset, 0); + + return 0; + } + + dev_dbg(&ts->client->dev, "NRST unavailable, try softreset\n"); + err = i2c_smbus_write_byte_data(ts->client, I2C_REG_SOFTRESET, + SOFTRESET_VALUE); + if (err) + return err; + else + return 0; +} + static int sx8654_open(struct input_dev *dev) { struct sx8654 *sx8654 = input_get_drvdata(dev); @@ -186,6 +210,17 @@ static int sx8654_probe(struct i2c_client *client, if (!sx8654) return -ENOMEM; + sx8654->gpio_reset = devm_gpiod_get_optional(&client->dev, "reset", + GPIOD_OUT_HIGH); + if (IS_ERR(sx8654->gpio_reset)) { + error = PTR_ERR(sx8654->gpio_reset); + if (error != -EPROBE_DEFER) + dev_err(&client->dev, "unable to get reset-gpio: %d\n", + error); + return error; + } + dev_dbg(&client->dev, "got GPIO reset pin\n"); + input = devm_input_allocate_device(&client->dev); if (!input) return -ENOMEM; @@ -206,10 +241,9 @@ static int sx8654_probe(struct i2c_client *client, input_set_drvdata(sx8654->input, sx8654); - error = i2c_smbus_write_byte_data(client, I2C_REG_SOFTRESET, - SOFTRESET_VALUE); + error = sx8654_reset(sx8654); if (error) { - dev_err(&client->dev, "writing softreset value failed"); + dev_err(&client->dev, "reset failed"); return error; }