From mboxrd@z Thu Jan 1 00:00:00 1970 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=-10.1 required=3.0 tests=DKIMWL_WL_HIGH,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_AU,INCLUDES_PATCH,MAILING_LIST_MULTI,SIGNED_OFF_BY, SPF_HELO_NONE,SPF_PASS,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 D387EC3B1A4 for ; Fri, 14 Feb 2020 16:51:32 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id A38E02067D for ; Fri, 14 Feb 2020 16:51:32 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1581699092; bh=NTq86b0DCPvXQOu5B4YCHjoybaZyE1rhW4Q21+e191c=; h=From:To:Cc:Subject:Date:In-Reply-To:References:List-ID:From; b=PeeLvm0Q3itR1VbYzaWnCg4Yc0FQY1rgLA16f40ur6AjhzO5eJoNIZhjnnUBCskl+ LjGYnFCPm2HaGPqyrmRMXAmf0fwX/4oy2FGOlKOuxwrk9X0k4OMyIj0blmQqZQhqEA +ecf6zQusyMAFIL6iiX4mLEl3CPDkKNe6+76oKQM= Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S2404626AbgBNQTp (ORCPT ); Fri, 14 Feb 2020 11:19:45 -0500 Received: from mail.kernel.org ([198.145.29.99]:52928 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S2392806AbgBNQTp (ORCPT ); Fri, 14 Feb 2020 11:19:45 -0500 Received: from sasha-vm.mshome.net (c-73-47-72-35.hsd1.nh.comcast.net [73.47.72.35]) (using TLSv1.2 with cipher ECDHE-RSA-AES128-GCM-SHA256 (128/128 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPSA id 244D124718; Fri, 14 Feb 2020 16:19:44 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1581697185; bh=NTq86b0DCPvXQOu5B4YCHjoybaZyE1rhW4Q21+e191c=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=omnOixlSkCbxrzzhEVjGMKFjNli10E+TK93q1zp30OSfbaPp03C+wcGrYZ+Nr5Us7 dvImN8uCOw9TFgZ8NP7npKsvKEpCBZ75rmn0Z6ZhBgrosFNAPDoC+mPvmB+9hI0hsp Kl5RcTfWwLA2ba7sczbjckxN4hmG75KhLqPXAoFo= From: Sasha Levin To: linux-kernel@vger.kernel.org, stable@vger.kernel.org Cc: Philipp Zabel , Marco Felsch , Andy Shevchenko , Dmitry Torokhov , Sasha Levin , linux-input@vger.kernel.org Subject: [PATCH AUTOSEL 4.14 115/186] Input: edt-ft5x06 - work around first register access error Date: Fri, 14 Feb 2020 11:16:04 -0500 Message-Id: <20200214161715.18113-115-sashal@kernel.org> X-Mailer: git-send-email 2.20.1 In-Reply-To: <20200214161715.18113-1-sashal@kernel.org> References: <20200214161715.18113-1-sashal@kernel.org> MIME-Version: 1.0 X-stable: review X-Patchwork-Hint: Ignore Content-Transfer-Encoding: 8bit Sender: linux-input-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-input@vger.kernel.org From: Philipp Zabel [ Upstream commit e112324cc0422c046f1cf54c56f333d34fa20885 ] The EP0700MLP1 returns bogus data on the first register read access (reading the threshold parameter from register 0x00): edt_ft5x06 2-0038: crc error: 0xfc expected, got 0x40 It ignores writes until then. This patch adds a dummy read after which the number of sensors and parameter read/writes work correctly. Signed-off-by: Philipp Zabel Signed-off-by: Marco Felsch Tested-by: Andy Shevchenko Reviewed-by: Andy Shevchenko Signed-off-by: Dmitry Torokhov Signed-off-by: Sasha Levin --- drivers/input/touchscreen/edt-ft5x06.c | 7 +++++++ 1 file changed, 7 insertions(+) diff --git a/drivers/input/touchscreen/edt-ft5x06.c b/drivers/input/touchscreen/edt-ft5x06.c index 5bf63f76dddac..4eff5b44640cf 100644 --- a/drivers/input/touchscreen/edt-ft5x06.c +++ b/drivers/input/touchscreen/edt-ft5x06.c @@ -888,6 +888,7 @@ static int edt_ft5x06_ts_probe(struct i2c_client *client, { const struct edt_i2c_chip_data *chip_data; struct edt_ft5x06_ts_data *tsdata; + u8 buf[2] = { 0xfc, 0x00 }; struct input_dev *input; unsigned long irq_flags; int error; @@ -957,6 +958,12 @@ static int edt_ft5x06_ts_probe(struct i2c_client *client, return error; } + /* + * Dummy read access. EP0700MLP1 returns bogus data on the first + * register read access and ignores writes. + */ + edt_ft5x06_ts_readwrite(tsdata->client, 2, buf, 2, buf); + edt_ft5x06_ts_set_regs(tsdata); edt_ft5x06_ts_get_defaults(&client->dev, tsdata); edt_ft5x06_ts_get_parameters(tsdata); -- 2.20.1