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=-17.3 required=3.0 tests=BAYES_00,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_AU,HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_CR_TRAILER, INCLUDES_PATCH,MAILING_LIST_MULTI,NICE_REPLY_A,SPF_HELO_NONE,SPF_PASS, URIBL_BLOCKED,USER_AGENT_SANE_1 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 CF27DC433E0 for ; Thu, 18 Feb 2021 18:10:10 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 8BCA664ED5 for ; Thu, 18 Feb 2021 18:10:10 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S231519AbhBRSKH (ORCPT ); Thu, 18 Feb 2021 13:10:07 -0500 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:32790 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S232455AbhBRPkY (ORCPT ); Thu, 18 Feb 2021 10:40:24 -0500 Received: from perceval.ideasonboard.com (perceval.ideasonboard.com [IPv6:2001:4b98:dc2:55:216:3eff:fef7:d647]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id F2478C061574; Thu, 18 Feb 2021 07:39:41 -0800 (PST) Received: from [192.168.0.20] (cpc89244-aztw30-2-0-cust3082.18-1.cable.virginm.net [86.31.172.11]) by perceval.ideasonboard.com (Postfix) with ESMTPSA id 0E3913E7; Thu, 18 Feb 2021 16:39:40 +0100 (CET) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=ideasonboard.com; s=mail; t=1613662780; bh=DmnvdwZV8yESaBMJksJjQrvF/K8QlpTjEqk5yRbepCU=; h=Reply-To:Subject:To:Cc:References:From:Date:In-Reply-To:From; b=jvXFmBq7P95/RylozLm6qa5y5bZxYWP0ZUAYBEFJKhxMU1NGGi04lR6hXoJnQ60Xf OUaZBTGvg1RC2B99xdWSvAHluasdew8Har76VRc8FEe/V82tNiVH7WvhJ5ToHTBmna cgreUgH0SMcjMXqOrJt3v/nANy0Q67YfqDpoCWQw= Reply-To: kieran.bingham+renesas@ideasonboard.com Subject: Re: [PATCH 11/16] media: i2c: max9286: Cache channel amplitude To: Jacopo Mondi , laurent.pinchart+renesas@ideasonboard.com, niklas.soderlund+renesas@ragnatech.se, geert@linux-m68k.org Cc: Mauro Carvalho Chehab , linux-media@vger.kernel.org, linux-renesas-soc@vger.kernel.org, linux-kernel@vger.kernel.org References: <20210216174146.106639-1-jacopo+renesas@jmondi.org> <20210216174146.106639-12-jacopo+renesas@jmondi.org> From: Kieran Bingham Organization: Ideas on Board Message-ID: <2b62ff38-7c9c-c24f-b7a6-8e3a65d3f669@ideasonboard.com> Date: Thu, 18 Feb 2021 15:39:37 +0000 User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:68.0) Gecko/20100101 Thunderbird/68.10.0 MIME-Version: 1.0 In-Reply-To: <20210216174146.106639-12-jacopo+renesas@jmondi.org> Content-Type: text/plain; charset=utf-8 Content-Language: en-GB Content-Transfer-Encoding: 7bit Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On 16/02/2021 17:41, Jacopo Mondi wrote: > Cache the current channel amplitude in a driver variable > to skip updating it if the new requested value is the same > as the currently configured one. > > Signed-off-by: Jacopo Mondi I like this model better than deciding outside of the call :-) Reviewed-by: Kieran Bingham > --- > drivers/media/i2c/max9286.c | 13 ++++++++++--- > 1 file changed, 10 insertions(+), 3 deletions(-) > > diff --git a/drivers/media/i2c/max9286.c b/drivers/media/i2c/max9286.c > index 1f14cd817fbf..4afb5ca06448 100644 > --- a/drivers/media/i2c/max9286.c > +++ b/drivers/media/i2c/max9286.c > @@ -164,6 +164,7 @@ struct max9286_priv { > bool mux_open; > > u32 init_rev_chan_mv; > + u32 rev_chan_mv; > > struct v4l2_ctrl_handler ctrls; > struct v4l2_ctrl *pixelrate; > @@ -340,8 +341,15 @@ static void max9286_configure_i2c(struct max9286_priv *priv, bool localack) > static void max9286_reverse_channel_setup(struct max9286_priv *priv, > unsigned int chan_amplitude) > { > + u8 chan_config; > + > + if (priv->rev_chan_mv == chan_amplitude) > + return; > + > + priv->rev_chan_mv = chan_amplitude; > + > /* Reverse channel transmission time: default to 1. */ > - u8 chan_config = MAX9286_REV_TRF(1); > + chan_config = MAX9286_REV_TRF(1); > > /* > * Reverse channel setup. > @@ -563,8 +571,7 @@ static int max9286_notify_bound(struct v4l2_async_notifier *notifier, > * - Disable auto-ack as communication on the control channel are now > * stable. > */ > - if (priv->init_rev_chan_mv < 170) > - max9286_reverse_channel_setup(priv, 170); > + max9286_reverse_channel_setup(priv, 170); > max9286_check_config_link(priv, priv->source_mask); > > /* >