From mboxrd@z Thu Jan 1 00:00:00 1970 From: Chaotian Jing Subject: [PATCH 2/2] mmc: mediatek: add bus_clk control Date: Fri, 28 Sep 2018 19:40:55 +0800 Message-ID: <1538134855-11198-3-git-send-email-chaotian.jing@mediatek.com> References: <1538134855-11198-1-git-send-email-chaotian.jing@mediatek.com> Mime-Version: 1.0 Content-Type: text/plain Return-path: In-Reply-To: <1538134855-11198-1-git-send-email-chaotian.jing@mediatek.com> Sender: linux-kernel-owner@vger.kernel.org To: Ulf Hansson Cc: Rob Herring , Mark Rutland , Matthias Brugger , Chaotian Jing , Ryder Lee , Wolfram Sang , Sean Wang , linux-mmc@vger.kernel.org, devicetree@vger.kernel.org, linux-arm-kernel@lists.infradead.org, linux-mediatek@lists.infradead.org, linux-kernel@vger.kernel.org, srv_heupstream@mediatek.com List-Id: devicetree@vger.kernel.org when gate MSDC0_HCLK, access register will hang, even the MSDC driver will never accessing register after HCLK was gated, but for safety, need gate the bus_clk(which used to access register) too. Signed-off-by: Chaotian Jing --- drivers/mmc/host/mtk-sd.c | 6 ++++++ 1 file changed, 6 insertions(+) diff --git a/drivers/mmc/host/mtk-sd.c b/drivers/mmc/host/mtk-sd.c index 0484138..1c1c967 100644 --- a/drivers/mmc/host/mtk-sd.c +++ b/drivers/mmc/host/mtk-sd.c @@ -387,6 +387,7 @@ struct msdc_host { struct clk *src_clk; /* msdc source clock */ struct clk *h_clk; /* msdc h_clk */ + struct clk *bus_clk; /* bus clock which used to access register */ struct clk *src_clk_cg; /* msdc source clock control gate */ u32 mclk; /* mmc subsystem clock frequency */ u32 src_clk_freq; /* source clock frequency */ @@ -660,12 +661,14 @@ static void msdc_gate_clock(struct msdc_host *host) { clk_disable_unprepare(host->src_clk_cg); clk_disable_unprepare(host->src_clk); + clk_disable_unprepare(host->bus_clk); clk_disable_unprepare(host->h_clk); } static void msdc_ungate_clock(struct msdc_host *host) { clk_prepare_enable(host->h_clk); + clk_prepare_enable(host->bus_clk); clk_prepare_enable(host->src_clk); clk_prepare_enable(host->src_clk_cg); while (!(readl(host->base + MSDC_CFG) & MSDC_CFG_CKSTB)) @@ -1900,6 +1903,9 @@ static int msdc_drv_probe(struct platform_device *pdev) goto host_free; } + host->bus_clk = devm_clk_get(&pdev->dev, "bus_clk"); + if (IS_ERR(host->bus_clk)) + host->bus_clk = NULL; /*source clock control gate is optional clock*/ host->src_clk_cg = devm_clk_get(&pdev->dev, "source_cg"); if (IS_ERR(host->src_clk_cg)) -- 1.8.1.1.dirty