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=-16.7 required=3.0 tests=BAYES_00, HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_CR_TRAILER,INCLUDES_PATCH, MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS,UNPARSEABLE_RELAY,URIBL_BLOCKED, 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 B0C5EC433ED for ; Sat, 17 Apr 2021 06:47:18 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 86FCA611CC for ; Sat, 17 Apr 2021 06:47:18 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S229870AbhDQGrm (ORCPT ); Sat, 17 Apr 2021 02:47:42 -0400 Received: from mailgw01.mediatek.com ([210.61.82.183]:57907 "EHLO mailgw01.mediatek.com" rhost-flags-OK-FAIL-OK-FAIL) by vger.kernel.org with ESMTP id S229629AbhDQGrl (ORCPT ); Sat, 17 Apr 2021 02:47:41 -0400 X-UUID: 0fce159f55274c4a9aa26a64f79cc043-20210417 X-UUID: 0fce159f55274c4a9aa26a64f79cc043-20210417 Received: from mtkmbs10n2.mediatek.inc [(172.21.101.183)] by mailgw01.mediatek.com (envelope-from ) (Cellopoint E-mail Firewall v4.1.14 Build 0819 with TLSv1.2 ECDHE-RSA-AES256-GCM-SHA384 256/256) with ESMTP id 378527476; Sat, 17 Apr 2021 14:47:12 +0800 Received: from mtkcas11.mediatek.inc (172.21.101.40) by mtkmbs07n1.mediatek.inc (172.21.101.16) with Microsoft SMTP Server (TLS) id 15.0.1497.2; Sat, 17 Apr 2021 14:47:10 +0800 Received: from localhost.localdomain (10.17.3.153) by mtkcas11.mediatek.inc (172.21.101.73) with Microsoft SMTP Server id 15.0.1497.2 via Frontend Transport; Sat, 17 Apr 2021 14:47:10 +0800 From: Qii Wang To: CC: , , , , , , , Subject: [PATCH 3/3] i2c: mediatek: Use scl_int_delay_ns to compensate clock-stretching Date: Sat, 17 Apr 2021 14:46:52 +0800 Message-ID: <1618642012-10444-4-git-send-email-qii.wang@mediatek.com> X-Mailer: git-send-email 1.9.1 In-Reply-To: <1618642012-10444-1-git-send-email-qii.wang@mediatek.com> References: <1618642012-10444-1-git-send-email-qii.wang@mediatek.com> MIME-Version: 1.0 Content-Type: text/plain X-MTK: N Precedence: bulk List-ID: X-Mailing-List: linux-i2c@vger.kernel.org The parameters of tSU,STA/tHD,STA/tSU,STOP maybe out of spec due to device clock-stretch or circuit loss, we could get a suitable scl_int_delay_ns from i2c_timings to compensate these parameters to meet the spec via EXT_CONF register. Signed-off-by: Qii Wang --- drivers/i2c/busses/i2c-mt65xx.c | 6 +++++- 1 file changed, 5 insertions(+), 1 deletion(-) diff --git a/drivers/i2c/busses/i2c-mt65xx.c b/drivers/i2c/busses/i2c-mt65xx.c index bf25acb..5ddfa4e 100644 --- a/drivers/i2c/busses/i2c-mt65xx.c +++ b/drivers/i2c/busses/i2c-mt65xx.c @@ -231,6 +231,7 @@ struct mtk_i2c { struct i2c_adapter adap; /* i2c host adapter */ struct device *dev; struct completion msg_complete; + struct i2c_timings timing_info; /* set in i2c probe */ void __iomem *base; /* i2c base addr */ @@ -607,7 +608,8 @@ static int mtk_i2c_check_ac_timing(struct mtk_i2c *i2c, else clk_ns = sample_ns / 2; - su_sta_cnt = DIV_ROUND_UP(spec->min_su_sta_ns, clk_ns); + su_sta_cnt = DIV_ROUND_UP(spec->min_su_sta_ns + + i2c->timing_info.scl_int_delay_ns, clk_ns); if (su_sta_cnt > max_sta_cnt) return -1; @@ -1176,6 +1178,8 @@ static int mtk_i2c_parse_dt(struct device_node *np, struct mtk_i2c *i2c) i2c->use_push_pull = of_property_read_bool(np, "mediatek,use-push-pull"); + i2c_parse_fw_timings(i2c->dev, &i2c->timing_info, true); + return 0; } -- 1.9.1