From patchwork Mon Mar 15 13:15:03 2021 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Jacopo Mondi X-Patchwork-Id: 12139291 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,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 3C62BC4161F for ; Mon, 15 Mar 2021 13:16:02 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 0C9EF64F21 for ; Mon, 15 Mar 2021 13:16:02 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S230410AbhCONPf (ORCPT ); Mon, 15 Mar 2021 09:15:35 -0400 Received: from relay9-d.mail.gandi.net ([217.70.183.199]:53273 "EHLO relay9-d.mail.gandi.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S229952AbhCONPT (ORCPT ); Mon, 15 Mar 2021 09:15:19 -0400 X-Originating-IP: 79.22.58.175 Received: from uno.homenet.telecomitalia.it (host-79-22-58-175.retail.telecomitalia.it [79.22.58.175]) (Authenticated sender: jacopo@jmondi.org) by relay9-d.mail.gandi.net (Postfix) with ESMTPSA id 87F16FF807; Mon, 15 Mar 2021 13:15:15 +0000 (UTC) From: Jacopo Mondi To: 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 Subject: [PATCH v2 09/18] media: i2c: max9271: Introduce wake_up() function Date: Mon, 15 Mar 2021 14:15:03 +0100 Message-Id: <20210315131512.133720-10-jacopo+renesas@jmondi.org> X-Mailer: git-send-email 2.30.0 In-Reply-To: <20210315131512.133720-1-jacopo+renesas@jmondi.org> References: <20210315131512.133720-1-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 exists 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. Do not handle the initial i2c address configuration in the library driver function as the camera module drivers control address reprogramming. Signed-off-by: Jacopo Mondi Reviewed-by: Kieran Bingham Reviewed-by: Laurent Pinchart --- drivers/media/i2c/max9271.c | 7 +++++++ drivers/media/i2c/max9271.h | 9 +++++++++ drivers/media/i2c/rdacm20.c | 2 +- drivers/media/i2c/rdacm21.c | 3 +-- 4 files changed, 18 insertions(+), 3 deletions(-) diff --git a/drivers/media/i2c/max9271.c b/drivers/media/i2c/max9271.c index 2c7dc7fb9846..f7bfe7266763 100644 --- a/drivers/media/i2c/max9271.c +++ b/drivers/media/i2c/max9271.c @@ -80,6 +80,13 @@ static int max9271_pclk_detect(struct max9271_device *dev) return -EIO; } +void max9271_wake_up(struct max9271_device *dev) +{ + 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 b9aaa0f7db42..2265ef7c65d4 100644 --- a/drivers/media/i2c/rdacm20.c +++ b/drivers/media/i2c/rdacm20.c @@ -459,7 +459,7 @@ static int rdacm20_initialize(struct rdacm20_device *dev) /* 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..7bce55adfd7c 100644 --- a/drivers/media/i2c/rdacm21.c +++ b/drivers/media/i2c/rdacm21.c @@ -452,8 +452,7 @@ static int rdacm21_initialize(struct rdacm21_device *dev) /* 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);