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=-9.0 required=3.0 tests=HEADER_FROM_DIFFERENT_DOMAINS, INCLUDES_PATCH,MAILING_LIST_MULTI,SIGNED_OFF_BY,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 2B377C43381 for ; Tue, 26 Feb 2019 13:11:53 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 042CB20651 for ; Tue, 26 Feb 2019 13:11:53 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1727399AbfBZNLq (ORCPT ); Tue, 26 Feb 2019 08:11:46 -0500 Received: from mailgw01.mediatek.com ([210.61.82.183]:19018 "EHLO mailgw01.mediatek.com" rhost-flags-OK-FAIL-OK-FAIL) by vger.kernel.org with ESMTP id S1726903AbfBZNLi (ORCPT ); Tue, 26 Feb 2019 08:11:38 -0500 X-UUID: bf05ce0f213d4e058122d7e0a93f9f8a-20190226 X-UUID: bf05ce0f213d4e058122d7e0a93f9f8a-20190226 Received: from mtkexhb02.mediatek.inc [(172.21.101.103)] by mailgw01.mediatek.com (envelope-from ) (mhqrelay.mediatek.com ESMTP with TLS) with ESMTP id 1623789549; Tue, 26 Feb 2019 21:11:32 +0800 Received: from MTKCAS06.mediatek.inc (172.21.101.30) by mtkmbs03n1.mediatek.inc (172.21.101.181) with Microsoft SMTP Server (TLS) id 15.0.1395.4; Tue, 26 Feb 2019 21:11:30 +0800 Received: from localhost.localdomain (10.17.3.153) by MTKCAS06.mediatek.inc (172.21.101.73) with Microsoft SMTP Server id 15.0.1395.4 via Frontend Transport; Tue, 26 Feb 2019 21:11:30 +0800 From: Qii Wang To: CC: , , , , , , , , , , Subject: [PATCH v5 3/5] i2c: mediatek: Add arb clock in i2c driver Date: Tue, 26 Feb 2019 21:10:58 +0800 Message-ID: <1551186660-16902-4-git-send-email-qii.wang@mediatek.com> X-Mailer: git-send-email 1.7.9.5 In-Reply-To: <1551186660-16902-1-git-send-email-qii.wang@mediatek.com> References: <1551186660-16902-1-git-send-email-qii.wang@mediatek.com> MIME-Version: 1.0 Content-Type: text/plain X-MTK: N Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org When two i2c controllers are internally connected to the same GPIO pins, the arb clock is needed to ensure that the waveforms do not interfere with each other. Signed-off-by: Qii Wang --- drivers/i2c/busses/i2c-mt65xx.c | 25 ++++++++++++++++++++++--- 1 file changed, 22 insertions(+), 3 deletions(-) diff --git a/drivers/i2c/busses/i2c-mt65xx.c b/drivers/i2c/busses/i2c-mt65xx.c index 428ac99..14d6b38 100644 --- a/drivers/i2c/busses/i2c-mt65xx.c +++ b/drivers/i2c/busses/i2c-mt65xx.c @@ -35,6 +35,7 @@ #include #define I2C_RS_TRANSFER (1 << 4) +#define I2C_ARB_LOST (1 << 3) #define I2C_HS_NACKERR (1 << 2) #define I2C_ACKERR (1 << 1) #define I2C_TRANSAC_COMP (1 << 0) @@ -181,6 +182,7 @@ struct mtk_i2c { struct clk *clk_main; /* main clock for i2c bus */ struct clk *clk_dma; /* DMA clock for i2c via DMA */ struct clk *clk_pmic; /* PMIC clock for i2c from PMIC */ + struct clk *clk_arb; /* Arbitrator clock for i2c */ bool have_pmic; /* can use i2c pins from PMIC */ bool use_push_pull; /* IO config push-pull mode */ @@ -299,8 +301,18 @@ static int mtk_i2c_clock_enable(struct mtk_i2c *i2c) if (ret) goto err_pmic; } + + if (i2c->clk_arb) { + ret = clk_prepare_enable(i2c->clk_arb); + if (ret) + goto err_arb; + } + return 0; +err_arb: + if (i2c->have_pmic) + clk_disable_unprepare(i2c->clk_pmic); err_pmic: clk_disable_unprepare(i2c->clk_main); err_main: @@ -311,6 +323,9 @@ static int mtk_i2c_clock_enable(struct mtk_i2c *i2c) static void mtk_i2c_clock_disable(struct mtk_i2c *i2c) { + if (i2c->clk_arb) + clk_disable_unprepare(i2c->clk_arb); + if (i2c->have_pmic) clk_disable_unprepare(i2c->clk_pmic); @@ -519,13 +534,13 @@ static int mtk_i2c_do_transfer(struct mtk_i2c *i2c, struct i2c_msg *msgs, /* Clear interrupt status */ mtk_i2c_writew(i2c, restart_flag | I2C_HS_NACKERR | I2C_ACKERR | - I2C_TRANSAC_COMP, OFFSET_INTR_STAT); + I2C_ARB_LOST | I2C_TRANSAC_COMP, OFFSET_INTR_STAT); mtk_i2c_writew(i2c, I2C_FIFO_ADDR_CLR, OFFSET_FIFO_ADDR_CLR); /* Enable interrupt */ mtk_i2c_writew(i2c, restart_flag | I2C_HS_NACKERR | I2C_ACKERR | - I2C_TRANSAC_COMP, OFFSET_INTR_MASK); + I2C_ARB_LOST | I2C_TRANSAC_COMP, OFFSET_INTR_MASK); /* Set transfer and transaction len */ if (i2c->op == I2C_MASTER_WRRD) { @@ -659,7 +674,7 @@ static int mtk_i2c_do_transfer(struct mtk_i2c *i2c, struct i2c_msg *msgs, /* Clear interrupt mask */ mtk_i2c_writew(i2c, ~(restart_flag | I2C_HS_NACKERR | I2C_ACKERR | - I2C_TRANSAC_COMP), OFFSET_INTR_MASK); + I2C_ARB_LOST | I2C_TRANSAC_COMP), OFFSET_INTR_MASK); if (i2c->op == I2C_MASTER_WR) { dma_unmap_single(i2c->dev, wpaddr, @@ -884,6 +899,10 @@ static int mtk_i2c_probe(struct platform_device *pdev) return PTR_ERR(i2c->clk_dma); } + i2c->clk_arb = devm_clk_get(&pdev->dev, "arb"); + if (IS_ERR(i2c->clk_arb)) + i2c->clk_arb = NULL; + clk = i2c->clk_main; if (i2c->have_pmic) { i2c->clk_pmic = devm_clk_get(&pdev->dev, "pmic"); -- 1.7.9.5