From ef60c9aa980b59a61c5464cc38fdfaecdec61e47 Mon Sep 17 00:00:00 2001 From: Alim Akhtar Date: Tue, 5 Jul 2016 15:28:53 +0530 Subject: rtc: s3c: Add s3c_rtc_{enable/disable}_clk in s3c_rtc_setfreq() commit 70c96dfac0e231424e17743bd52f6cd2ff1f2439 upstream. As per code flow s3c_rtc_setfreq() will get called with rtc clock disabled and in set_freq we perform h/w registers read/write, which results in a kernel crash on exynos7 platform while probing rtc driver. Below is code flow: s3c_rtc_probe() clk_prepare_enable(info->rtc_clk) // rtc clock enabled s3c_rtc_gettime() // will enable clk if not done, and disable it upon exit s3c_rtc_setfreq() //then this will be called with clk disabled This patch take cares of such issue by adding s3c_rtc_{enable/disable}_clk in s3c_rtc_setfreq(). Fixes: 24e1455493da ("drivers/rtc/rtc-s3c.c: delete duplicate clock control") Signed-off-by: Alim Akhtar Reviewed-by: Krzysztof Kozlowski Reviewed-by: Pankaj Dubey Tested-by: Pankaj Dubey Signed-off-by: Alexandre Belloni Signed-off-by: Greg Kroah-Hartman --- drivers/rtc/rtc-s3c.c | 2 ++ 1 file changed, 2 insertions(+) (limited to 'drivers/rtc') diff --git a/drivers/rtc/rtc-s3c.c b/drivers/rtc/rtc-s3c.c index ffb860d18701..f92528822f06 100644 --- a/drivers/rtc/rtc-s3c.c +++ b/drivers/rtc/rtc-s3c.c @@ -149,12 +149,14 @@ static int s3c_rtc_setfreq(struct s3c_rtc *info, int freq) if (!is_power_of_2(freq)) return -EINVAL; + s3c_rtc_enable_clk(info); spin_lock_irq(&info->pie_lock); if (info->data->set_freq) info->data->set_freq(info, freq); spin_unlock_irq(&info->pie_lock); + s3c_rtc_disable_clk(info); return 0; } -- cgit v1.2.3