Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1754897AbbG3AZA (ORCPT ); Wed, 29 Jul 2015 20:25:00 -0400 Received: from down.free-electrons.com ([37.187.137.238]:56889 "EHLO mail.free-electrons.com" rhost-flags-OK-OK-OK-FAIL) by vger.kernel.org with ESMTP id S1754477AbbG3AYz (ORCPT ); Wed, 29 Jul 2015 20:24:55 -0400 From: Alexandre Belloni To: Nicolas Ferre Cc: Boris Brezillon , linux-arm-kernel@lists.infradead.org, rtc-linux@googlegroups.com, Alessandro Zummo , linux-kernel@vger.kernel.org, Alexandre Belloni Subject: [PATCH 4/5] rtc: at91sam9: get sclk rate after enabling it Date: Thu, 30 Jul 2015 02:24:31 +0200 Message-Id: <1438215872-27794-4-git-send-email-alexandre.belloni@free-electrons.com> X-Mailer: git-send-email 2.1.4 In-Reply-To: <1438215872-27794-1-git-send-email-alexandre.belloni@free-electrons.com> References: <1438215872-27794-1-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 Content-Length: 1528 Lines: 48 See help for clk_get_rate(): "obtain the current clock rate (in Hz) for a clock source. This is only valid once the clock source has been enabled." It currently returns the correct value but that may not stay that way. Signed-off-by: Alexandre Belloni --- drivers/rtc/rtc-at91sam9.c | 13 +++++++------ 1 file changed, 7 insertions(+), 6 deletions(-) diff --git a/drivers/rtc/rtc-at91sam9.c b/drivers/rtc/rtc-at91sam9.c index 23f721d049b2..f9e85ace5e71 100644 --- a/drivers/rtc/rtc-at91sam9.c +++ b/drivers/rtc/rtc-at91sam9.c @@ -425,18 +425,19 @@ static int at91_rtc_probe(struct platform_device *pdev) if (IS_ERR(rtc->sclk)) return PTR_ERR(rtc->sclk); - sclk_rate = clk_get_rate(rtc->sclk); - if (!sclk_rate || sclk_rate > AT91_RTT_RTPRES) { - dev_err(&pdev->dev, "Invalid slow clock rate\n"); - return -EINVAL; - } - ret = clk_prepare_enable(rtc->sclk); if (ret) { dev_err(&pdev->dev, "Could not enable slow clock\n"); return ret; } + sclk_rate = clk_get_rate(rtc->sclk); + if (!sclk_rate || sclk_rate > AT91_RTT_RTPRES) { + dev_err(&pdev->dev, "Invalid slow clock rate\n"); + ret = -EINVAL; + goto err_clk; + } + mr = rtt_readl(rtc, MR); /* unless RTT is counting at 1 Hz, re-initialize it */ -- 2.1.4 -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/