From patchwork Tue Sep 8 15:16:17 2020 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: "Wang, Jiada" X-Patchwork-Id: 255003 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=-12.8 required=3.0 tests=BAYES_00, HEADER_FROM_DIFFERENT_DOMAINS, INCLUDES_PATCH, MAILING_LIST_MULTI, SIGNED_OFF_BY, SPF_HELO_NONE,SPF_PASS,URIBL_BLOCKED,USER_AGENT_GIT autolearn=ham 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 B1EFDC433E2 for ; Tue, 8 Sep 2020 20:04:45 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 8A38320768 for ; Tue, 8 Sep 2020 20:04:45 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1730403AbgIHUEn (ORCPT ); Tue, 8 Sep 2020 16:04:43 -0400 Received: from esa1.mentor.iphmx.com ([68.232.129.153]:33732 "EHLO esa1.mentor.iphmx.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1730394AbgIHPXq (ORCPT ); Tue, 8 Sep 2020 11:23:46 -0400 IronPort-SDR: A73xvdNyxsY1l7xwjxJRzrRhOuzXupkcYc7ZnS9I/MNbCnhE9r2NMD/gVfWfXdzVty37py88yS NsXtFfY/Muyg63BxZjpYbBXfRFG04MmYT57C+RXVz3+GCiQompLecUbPTf3XMslGO9QxZutYcm up9zpP34cHyNIjuEQb4bmnArGmKRsAqVQJeEEjoI6qmG7OD/+5r+/46QfuanAknkowz+r4WEmX IZEhD2jPoyRil9+uKahwsYvK6FCYApCTsqvO7emc+uIJe8z/xQdKmOenGmv46BKG+QbiRE3Vrk YjI= X-IronPort-AV: E=Sophos;i="5.76,406,1592899200"; d="scan'208";a="54874117" Received: from orw-gwy-02-in.mentorg.com ([192.94.38.167]) by esa1.mentor.iphmx.com with ESMTP; 08 Sep 2020 07:16:21 -0800 IronPort-SDR: znhbrejcoFm31kQaQGxCn2w+iduSV/IKA2TT4r1XS0EBSjw2Pr5fv1wQumrikkaJ1hSuarFb4s GV3qBM/i3FpkYx6cmzVbLKW8qjXfCZ8k6zSdKu0b+ABC5WveJ1o2d4k8gvxQ8QXOtB/wbotcBs TW68eAoAHaXsXVvjJ5x/aQYwqluOE83Bsgh0GFK6EXUY8UrxELnM5osWO7dmkESPBhEN7a/eXg uKiZ33eIxolrJL0wGX6LZatW/wPKcNJABrnVbCSAQZ3EMQr24R8ZRk+x0sKCoQbgj/DHNUh1oV Hsk= From: Jiada Wang To: , CC: , , , , , Subject: [PATCH v3 1/1] Input: atmel_mxt_ts - implement I2C retries Date: Wed, 9 Sep 2020 00:16:17 +0900 Message-ID: <20200908151617.12199-1-jiada_wang@mentor.com> X-Mailer: git-send-email 2.17.1 MIME-Version: 1.0 Sender: linux-input-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-input@vger.kernel.org From: Nick Dyer Some maXTouch chips (eg mXT1386) will not respond on the first I2C request when they are in a sleep state. It must be retried after a delay for the chip to wake up. Signed-off-by: Nick Dyer Acked-by: Yufeng Shen (cherry picked from ndyer/linux/for-upstream commit 63fd7a2cd03c3a572a5db39c52f4856819e1835d) [gdavis: Forward port and fix conflicts.] Signed-off-by: George G. Davis [jiada: return exact errno when i2c_transfer & i2c_master_send fails, add "_MS" suffix MXT_WAKEUP_TIME] Signed-off-by: Jiada Wang --- drivers/input/touchscreen/atmel_mxt_ts.c | 45 ++++++++++++++++-------- 1 file changed, 30 insertions(+), 15 deletions(-) diff --git a/drivers/input/touchscreen/atmel_mxt_ts.c b/drivers/input/touchscreen/atmel_mxt_ts.c index a2189739e30f..145780f78122 100644 --- a/drivers/input/touchscreen/atmel_mxt_ts.c +++ b/drivers/input/touchscreen/atmel_mxt_ts.c @@ -196,6 +196,7 @@ enum t100_type { #define MXT_CRC_TIMEOUT 1000 /* msec */ #define MXT_FW_RESET_TIME 3000 /* msec */ #define MXT_FW_CHG_TIMEOUT 300 /* msec */ +#define MXT_WAKEUP_TIME_MS 25 /* msec */ /* Command to unlock bootloader */ #define MXT_UNLOCK_CMD_MSB 0xaa @@ -626,6 +627,7 @@ static int __mxt_read_reg(struct i2c_client *client, struct i2c_msg xfer[2]; u8 buf[2]; int ret; + bool retry = false; buf[0] = reg & 0xff; buf[1] = (reg >> 8) & 0xff; @@ -642,17 +644,22 @@ static int __mxt_read_reg(struct i2c_client *client, xfer[1].len = len; xfer[1].buf = val; - ret = i2c_transfer(client->adapter, xfer, 2); - if (ret == 2) { - ret = 0; - } else { - if (ret >= 0) - ret = -EIO; - dev_err(&client->dev, "%s: i2c transfer failed (%d)\n", - __func__, ret); +retry_read: + ret = i2c_transfer(client->adapter, xfer, ARRAY_SIZE(xfer)); + if (ret != ARRAY_SIZE(xfer)) { + if (!retry) { + dev_dbg(&client->dev, "%s: i2c retry\n", __func__); + msleep(MXT_WAKEUP_TIME_MS); + retry = true; + goto retry_read; + } else { + dev_err(&client->dev, "%s: i2c transfer failed (%d)\n", + __func__, ret); + return ret < 0 ? ret : -EIO; + } } - return ret; + return 0; } static int __mxt_write_reg(struct i2c_client *client, u16 reg, u16 len, @@ -661,6 +668,7 @@ static int __mxt_write_reg(struct i2c_client *client, u16 reg, u16 len, u8 *buf; size_t count; int ret; + bool retry = false; count = len + 2; buf = kmalloc(count, GFP_KERNEL); @@ -671,14 +679,21 @@ static int __mxt_write_reg(struct i2c_client *client, u16 reg, u16 len, buf[1] = (reg >> 8) & 0xff; memcpy(&buf[2], val, len); +retry_write: ret = i2c_master_send(client, buf, count); - if (ret == count) { - ret = 0; + if (ret != count) { + if (!retry) { + dev_dbg(&client->dev, "%s: i2c retry\n", __func__); + msleep(MXT_WAKEUP_TIME_MS); + retry = true; + goto retry_write; + } else { + dev_err(&client->dev, "%s: i2c send failed (%d)\n", + __func__, ret); + ret = ret < 0 ? ret : -EIO; + } } else { - if (ret >= 0) - ret = -EIO; - dev_err(&client->dev, "%s: i2c send failed (%d)\n", - __func__, ret); + ret = 0; } kfree(buf);