On Tue, Sep 23, 2014 at 11:38:48AM +0200, Boris BREZILLON wrote: > @@ -328,6 +328,7 @@ static int at91_rtc_probe(struct platform_device *pdev) > struct sam9_rtc *rtc; > int ret, irq; > u32 mr; > + unsigned int sclk_rate; > > irq = platform_get_irq(pdev, 0); > if (irq < 0) { > @@ -385,11 +386,27 @@ static int at91_rtc_probe(struct platform_device *pdev) > return -ENOMEM; > } > > + rtc->sclk = devm_clk_get(&pdev->dev, NULL); > + if (IS_ERR(rtc->sclk)) > + return PTR_ERR(rtc->sclk); > + > + sclk_rate = clk_get_rate(rtc->sclk); > + if (!sclk_rate || sclk_rate > AT91_RTT_RTTRST) { You probably meant AT91_RTT_RTPRES here. > + dev_err(&pdev->dev, "Invalid slow clock rate"); > + return -EINVAL; > + } > + > + ret = clk_prepare_enable(rtc->sclk); > + if (ret) { > + dev_err(&pdev->dev, "Could not enable slow clock"); > + return ret; > + } > + > mr = rtt_readl(rtc, MR); > > /* unless RTT is counting at 1 Hz, re-initialize it */ > - if ((mr & AT91_RTT_RTPRES) != AT91_SLOW_CLOCK) { > - mr = AT91_RTT_RTTRST | (AT91_SLOW_CLOCK & AT91_RTT_RTPRES); > + if ((mr & AT91_RTT_RTPRES) != sclk_rate) { > + mr = AT91_RTT_RTTRST | (sclk_rate & AT91_RTT_RTPRES); > gpbr_writel(rtc, 0); > } Johan -- To unsubscribe from this list: send the line "unsubscribe devicetree" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html