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 Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id 6E4D6C433FE for ; Mon, 24 Jan 2022 19:52:54 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1352348AbiAXTwt (ORCPT ); Mon, 24 Jan 2022 14:52:49 -0500 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:56314 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1356831AbiAXTr0 (ORCPT ); Mon, 24 Jan 2022 14:47:26 -0500 Received: from ams.source.kernel.org (ams.source.kernel.org [IPv6:2604:1380:4601:e00::1]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 318A3C038AEC; Mon, 24 Jan 2022 11:23:19 -0800 (PST) Received: from smtp.kernel.org (relay.kernel.org [52.25.139.140]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by ams.source.kernel.org (Postfix) with ESMTPS id CCA15B8123F; Mon, 24 Jan 2022 19:23:18 +0000 (UTC) Received: by smtp.kernel.org (Postfix) with ESMTPSA id E1643C340E5; Mon, 24 Jan 2022 19:23:16 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=linuxfoundation.org; s=korg; t=1643052197; bh=+5B2a8108S7AUZGD06016KZBTI+r/kEmX5RhV/EvtKU=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=ihVZ/g2cXH+wcz1KNpmiL1gXE5TeK5iw0ulnZvCa6/TbIzBZBeie0FKzEHKojhKmv UjKG4tqyLp5M7U4C/XwwUVaCJK8hocU97RiAcTNoRtHDPedUeKvyX4FEpgw1Wje45Z M7Dust+j66aGsQTpgzb+jljEF2Up6aMIqMMwvi0U= From: Greg Kroah-Hartman To: linux-kernel@vger.kernel.org Cc: Greg Kroah-Hartman , stable@vger.kernel.org, Suresh Udipi , Michael Rodin , =?UTF-8?q?Niklas=20S=C3=B6derlund?= , Hans Verkuil , Mauro Carvalho Chehab Subject: [PATCH 4.19 213/239] media: rcar-csi2: Optimize the selection PHTW register Date: Mon, 24 Jan 2022 19:44:11 +0100 Message-Id: <20220124183949.887495650@linuxfoundation.org> X-Mailer: git-send-email 2.34.1 In-Reply-To: <20220124183943.102762895@linuxfoundation.org> References: <20220124183943.102762895@linuxfoundation.org> User-Agent: quilt/0.66 MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit Precedence: bulk List-ID: X-Mailing-List: stable@vger.kernel.org From: Suresh Udipi commit 549cc89cd09a85aaa16dc07ef3db811d5cf9bcb1 upstream. PHTW register is selected based on default bit rate from Table[1]. for the bit rates less than or equal to 250. Currently first value of default bit rate which is greater than or equal to the caculated mbps is selected. This selection can be further improved by selecting the default bit rate which is nearest to the calculated value. [1] specs r19uh0105ej0200-r-car-3rd-generation.pdf [Table 25.12] Fixes: 769afd212b16 ("media: rcar-csi2: add Renesas R-Car MIPI CSI-2 receiver driver") Signed-off-by: Suresh Udipi Signed-off-by: Michael Rodin Reviewed-by: Niklas Söderlund Signed-off-by: Hans Verkuil Signed-off-by: Mauro Carvalho Chehab Signed-off-by: Greg Kroah-Hartman --- drivers/media/platform/rcar-vin/rcar-csi2.c | 9 ++++++++- 1 file changed, 8 insertions(+), 1 deletion(-) --- a/drivers/media/platform/rcar-vin/rcar-csi2.c +++ b/drivers/media/platform/rcar-vin/rcar-csi2.c @@ -843,10 +843,17 @@ static int rcsi2_phtw_write_mbps(struct const struct rcsi2_mbps_reg *values, u16 code) { const struct rcsi2_mbps_reg *value; + const struct rcsi2_mbps_reg *prev_value = NULL; - for (value = values; value->mbps; value++) + for (value = values; value->mbps; value++) { if (value->mbps >= mbps) break; + prev_value = value; + } + + if (prev_value && + ((mbps - prev_value->mbps) <= (value->mbps - mbps))) + value = prev_value; if (!value->mbps) { dev_err(priv->dev, "Unsupported PHY speed (%u Mbps)", mbps);