From patchwork Wed Jun 16 12:46:08 2021 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Jacopo Mondi X-Patchwork-Id: 12325065 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=-16.8 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=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 E7818C48BE6 for ; Wed, 16 Jun 2021 12:46:03 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id D542160FDB for ; Wed, 16 Jun 2021 12:46:03 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S232985AbhFPMsI (ORCPT ); Wed, 16 Jun 2021 08:48:08 -0400 Received: from relay5-d.mail.gandi.net ([217.70.183.197]:43289 "EHLO relay5-d.mail.gandi.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S232941AbhFPMsB (ORCPT ); Wed, 16 Jun 2021 08:48:01 -0400 Received: (Authenticated sender: jacopo@jmondi.org) by relay5-d.mail.gandi.net (Postfix) with ESMTPSA id 16C791C0006; Wed, 16 Jun 2021 12:45:51 +0000 (UTC) From: Jacopo Mondi To: Hans Verkuil , kieran.bingham+renesas@ideasonboard.com, laurent.pinchart+renesas@ideasonboard.com, niklas.soderlund+renesas@ragnatech.se, geert@linux-m68k.org Cc: Jacopo Mondi , Mauro Carvalho Chehab , linux-media@vger.kernel.org, linux-renesas-soc@vger.kernel.org, linux-kernel@vger.kernel.org, Laurent Pinchart Subject: [PATCH v5 07/15] media: i2c: max9271: Introduce wake_up() function Date: Wed, 16 Jun 2021 14:46:08 +0200 Message-Id: <20210616124616.49249-8-jacopo+renesas@jmondi.org> X-Mailer: git-send-email 2.31.1 In-Reply-To: <20210616124616.49249-1-jacopo+renesas@jmondi.org> References: <20210616124616.49249-1-jacopo+renesas@jmondi.org> MIME-Version: 1.0 Precedence: bulk List-ID: X-Mailing-List: linux-media@vger.kernel.org The MAX9271 chip manual prescribes a delay of 5 milliseconds after the chip exits from low power state. Add a new function to the max9271 library driver that wakes up the chip with a dummy i2c transaction and implements the correct delay of 5 milliseconds after the chip exits from low power state. Use the newly introduced function in the rdacm20 and rdacm21 camera drivers. The former was not respecting the required delay while the latter was waiting for a too-short timeout. Signed-off-by: Jacopo Mondi Reviewed-by: Kieran Bingham Reviewed-by: Laurent Pinchart --- drivers/media/i2c/max9271.c | 12 ++++++++++++ drivers/media/i2c/max9271.h | 9 +++++++++ drivers/media/i2c/rdacm20.c | 4 +--- drivers/media/i2c/rdacm21.c | 5 +---- 4 files changed, 23 insertions(+), 7 deletions(-) diff --git a/drivers/media/i2c/max9271.c b/drivers/media/i2c/max9271.c index 2c7dc7fb9846..ff86c8c4ea61 100644 --- a/drivers/media/i2c/max9271.c +++ b/drivers/media/i2c/max9271.c @@ -80,6 +80,18 @@ static int max9271_pclk_detect(struct max9271_device *dev) return -EIO; } +void max9271_wake_up(struct max9271_device *dev) +{ + /* + * Use the chip default address as this function has to be called + * before any other one. + */ + dev->client->addr = MAX9271_DEFAULT_ADDR; + i2c_smbus_read_byte(dev->client); + usleep_range(5000, 8000); +} +EXPORT_SYMBOL_GPL(max9271_wake_up); + int max9271_set_serial_link(struct max9271_device *dev, bool enable) { int ret; diff --git a/drivers/media/i2c/max9271.h b/drivers/media/i2c/max9271.h index d78fb21441e9..dc5e4e70ba6f 100644 --- a/drivers/media/i2c/max9271.h +++ b/drivers/media/i2c/max9271.h @@ -85,6 +85,15 @@ struct max9271_device { struct i2c_client *client; }; +/** + * max9271_wake_up() - Wake up the serializer by issuing an i2c transaction + * @dev: The max9271 device + * + * This function shall be called before any other interaction with the + * serializer. + */ +void max9271_wake_up(struct max9271_device *dev); + /** * max9271_set_serial_link() - Enable/disable serial link * @dev: The max9271 device diff --git a/drivers/media/i2c/rdacm20.c b/drivers/media/i2c/rdacm20.c index 90eb73f0e6e9..c1a717153303 100644 --- a/drivers/media/i2c/rdacm20.c +++ b/drivers/media/i2c/rdacm20.c @@ -455,9 +455,7 @@ static int rdacm20_initialize(struct rdacm20_device *dev) unsigned int retry = 3; int ret; - /* Verify communication with the MAX9271: ping to wakeup. */ - dev->serializer->client->addr = MAX9271_DEFAULT_ADDR; - i2c_smbus_read_byte(dev->serializer->client); + max9271_wake_up(dev->serializer); /* Serial link disabled during config as it needs a valid pixel clock. */ ret = max9271_set_serial_link(dev->serializer, false); diff --git a/drivers/media/i2c/rdacm21.c b/drivers/media/i2c/rdacm21.c index 179d107f494c..553e3f03752b 100644 --- a/drivers/media/i2c/rdacm21.c +++ b/drivers/media/i2c/rdacm21.c @@ -450,10 +450,7 @@ static int rdacm21_initialize(struct rdacm21_device *dev) { int ret; - /* Verify communication with the MAX9271: ping to wakeup. */ - dev->serializer.client->addr = MAX9271_DEFAULT_ADDR; - i2c_smbus_read_byte(dev->serializer.client); - usleep_range(3000, 5000); + max9271_wake_up(&dev->serializer); /* Enable reverse channel and disable the serial link. */ ret = max9271_set_serial_link(&dev->serializer, false);