From patchwork Mon Apr 12 09:34:37 2021 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Jacopo Mondi X-Patchwork-Id: 419737 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=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 44D40C43462 for ; Mon, 12 Apr 2021 09:37:00 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 1B4F261241 for ; Mon, 12 Apr 2021 09:37:00 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S241207AbhDLJhO (ORCPT ); Mon, 12 Apr 2021 05:37:14 -0400 Received: from relay12.mail.gandi.net ([217.70.178.232]:38635 "EHLO relay12.mail.gandi.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S238501AbhDLJeo (ORCPT ); Mon, 12 Apr 2021 05:34:44 -0400 Received: from uno.lan (93-34-118-233.ip49.fastwebnet.it [93.34.118.233]) (Authenticated sender: jacopo@jmondi.org) by relay12.mail.gandi.net (Postfix) with ESMTPSA id C55FC20000B; Mon, 12 Apr 2021 09:34:23 +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, Laurent Pinchart Subject: [PATCH v4 03/17] media: i2c: max9286: Cache channel amplitude Date: Mon, 12 Apr 2021 11:34:37 +0200 Message-Id: <20210412093451.14198-4-jacopo+renesas@jmondi.org> X-Mailer: git-send-email 2.31.1 In-Reply-To: <20210412093451.14198-1-jacopo+renesas@jmondi.org> References: <20210412093451.14198-1-jacopo+renesas@jmondi.org> MIME-Version: 1.0 Precedence: bulk List-ID: X-Mailing-List: linux-media@vger.kernel.org Cache the current channel amplitude in a driver variable to skip updating it if the newly requested value is the same as the currently configured one. Reviewed-by: Kieran Bingham Reviewed-by: Laurent Pinchart Signed-off-by: Jacopo Mondi --- 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 82ec05e96cb7..ed1cdefe7c30 100644 --- a/drivers/media/i2c/max9286.c +++ b/drivers/media/i2c/max9286.c @@ -165,6 +165,7 @@ struct max9286_priv { /* The initial reverse control channel amplitude. */ u32 init_rev_chan_mv; + u32 rev_chan_mv; struct v4l2_ctrl_handler ctrls; struct v4l2_ctrl *pixelrate; @@ -341,8 +342,15 @@ 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. @@ -564,8 +572,7 @@ 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); /*