From patchwork Mon Mar 15 13:15:08 2021 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Jacopo Mondi X-Patchwork-Id: 12139303 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 5AD2AC43333 for ; Mon, 15 Mar 2021 13:16:31 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 3538064EF2 for ; Mon, 15 Mar 2021 13:16:31 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S230527AbhCONQB (ORCPT ); Mon, 15 Mar 2021 09:16:01 -0400 Received: from relay9-d.mail.gandi.net ([217.70.183.199]:60437 "EHLO relay9-d.mail.gandi.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S230371AbhCONPf (ORCPT ); Mon, 15 Mar 2021 09:15:35 -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 95320FF803; Mon, 15 Mar 2021 13:15:30 +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 v2 14/18] media: i2c: max9286: Cache channel amplitude Date: Mon, 15 Mar 2021 14:15:08 +0100 Message-Id: <20210315131512.133720-15-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 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); /*