From 8918bd8a5f6c37963ba04ae79ad6488108894ab9 Mon Sep 17 00:00:00 2001 From: Alexandre Belloni Date: Tue, 28 Jul 2015 21:51:10 +0200 Subject: [PATCH] rtc: at91sam9: get sclk rate after enabling it 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 Acked-by: Boris Brezillon Acked-by: Nicolas Ferre --- 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 23f721d..f9e85ac 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 */ -- 2.7.4