From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1753129AbbGaJp1 (ORCPT ); Fri, 31 Jul 2015 05:45:27 -0400 Received: from down.free-electrons.com ([37.187.137.238]:33727 "EHLO mail.free-electrons.com" rhost-flags-OK-OK-OK-FAIL) by vger.kernel.org with ESMTP id S1751846AbbGaJkS (ORCPT ); Fri, 31 Jul 2015 05:40:18 -0400 From: Alexandre Belloni To: Nicolas Ferre Cc: Boris Brezillon , Maxime Ripard , Jean-Christophe Plagniol-Villard , linux-arm-kernel@lists.infradead.org, linux-kernel@vger.kernel.org, Alexandre Belloni , Alessandro Zummo , rtc-linux@googlegroups.com Subject: [PATCH 15/23] rtc: at91rm9200: get and use slow clock Date: Fri, 31 Jul 2015 11:39:51 +0200 Message-Id: <1438335599-3301-16-git-send-email-alexandre.belloni@free-electrons.com> X-Mailer: git-send-email 2.1.4 In-Reply-To: <1438335599-3301-1-git-send-email-alexandre.belloni@free-electrons.com> References: <1438335599-3301-1-git-send-email-alexandre.belloni@free-electrons.com> Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Commit dca1a4b5ff6e ("clk: at91: keep slow clk enabled to prevent system hang") added a workaround for the slow clock as it is not properly handled by its users. Get and use the slow clock as it is necessary for the at91rm9200 rtc. Signed-off-by: Alexandre Belloni --- Cc: Alessandro Zummo Cc: rtc-linux@googlegroups.com drivers/rtc/rtc-at91rm9200.c | 27 ++++++++++++++++++++++++--- 1 file changed, 24 insertions(+), 3 deletions(-) diff --git a/drivers/rtc/rtc-at91rm9200.c b/drivers/rtc/rtc-at91rm9200.c index 35efd3f75b18..8093d9e50619 100644 --- a/drivers/rtc/rtc-at91rm9200.c +++ b/drivers/rtc/rtc-at91rm9200.c @@ -24,6 +24,7 @@ #include #include #include +#include #include #include #include @@ -59,6 +60,7 @@ static bool suspended; static DEFINE_SPINLOCK(suspended_lock); static unsigned long cached_events; static u32 at91_rtc_imr; +static struct clk *sclk; static void at91_rtc_write_ier(u32 mask) { @@ -407,6 +409,16 @@ static int __init at91_rtc_probe(struct platform_device *pdev) return -ENOMEM; } + sclk = devm_clk_get(&pdev->dev, NULL); + if (IS_ERR(sclk)) + return PTR_ERR(sclk); + + ret = clk_prepare_enable(sclk); + if (ret) { + dev_err(&pdev->dev, "Could not enable slow clock\n"); + return ret; + } + at91_rtc_write(AT91_RTC_CR, 0); at91_rtc_write(AT91_RTC_MR, 0); /* 24 hour mode */ @@ -420,7 +432,7 @@ static int __init at91_rtc_probe(struct platform_device *pdev) "at91_rtc", pdev); if (ret) { dev_err(&pdev->dev, "IRQ %d already in use.\n", irq); - return ret; + goto err_clk; } /* cpu init code should really have flagged this device as @@ -431,8 +443,10 @@ static int __init at91_rtc_probe(struct platform_device *pdev) rtc = devm_rtc_device_register(&pdev->dev, pdev->name, &at91_rtc_ops, THIS_MODULE); - if (IS_ERR(rtc)) - return PTR_ERR(rtc); + if (IS_ERR(rtc)) { + ret = PTR_ERR(rtc); + goto err_clk; + } platform_set_drvdata(pdev, rtc); /* enable SECEV interrupt in order to initialize at91_rtc_upd_rdy @@ -442,6 +456,11 @@ static int __init at91_rtc_probe(struct platform_device *pdev) dev_info(&pdev->dev, "AT91 Real Time Clock driver.\n"); return 0; + +err_clk: + clk_disable_unprepare(sclk); + + return ret; } /* @@ -454,6 +473,8 @@ static int __exit at91_rtc_remove(struct platform_device *pdev) AT91_RTC_SECEV | AT91_RTC_TIMEV | AT91_RTC_CALEV); + clk_disable_unprepare(sclk); + return 0; } -- 2.1.4