* [PATCH v2 1/2] rtc: s3c: Remove unnecessary call to disable already disabled clock
@ 2016-07-05 9:58 Alim Akhtar
2016-07-05 9:58 ` [PATCH v2 2/2] rtc: s3c: Add s3c_rtc_{enable/disable}_clk in s3c_rtc_setfreq() Alim Akhtar
2016-07-19 15:50 ` [PATCH v2 1/2] rtc: s3c: Remove unnecessary call to disable already disabled clock Alexandre Belloni
0 siblings, 2 replies; 4+ messages in thread
From: Alim Akhtar @ 2016-07-05 9:58 UTC (permalink / raw)
To: rtc-linux, linux-kernel
Cc: alexandre.belloni, k.kozlowski, javier, pankaj.dubey, alim.akhtar
At the end of s3c_rtc_probe(), s3c_rtc_disable_clk() being called with rtc
clock already disabled (by s3c_rtc_gettime()), which looks extra and
unnecessary call. Lets clean it up.
Signed-off-by: Alim Akhtar <alim.akhtar@samsung.com>
Reviewed-by: Krzysztof Kozlowski <k.kozlowski@samsung.com>
Reviewed-by: Pankaj Dubey <pankaj.dubey@samsung.com>
Tested-by: Pankaj Dubey <pankaj.dubey@samsung.com>
---
drivers/rtc/rtc-s3c.c | 2 --
1 file changed, 2 deletions(-)
* Changes from v1
-updated commit message as suggested by Krzysztof.
-updated reviewed-by, tested-by tags
diff --git a/drivers/rtc/rtc-s3c.c b/drivers/rtc/rtc-s3c.c
index d01ad7e..b083840 100644
--- a/drivers/rtc/rtc-s3c.c
+++ b/drivers/rtc/rtc-s3c.c
@@ -577,8 +577,6 @@ static int s3c_rtc_probe(struct platform_device *pdev)
s3c_rtc_setfreq(info, 1);
- s3c_rtc_disable_clk(info);
-
return 0;
err_nortc:
--
1.7.10.4
^ permalink raw reply related [flat|nested] 4+ messages in thread
* [PATCH v2 2/2] rtc: s3c: Add s3c_rtc_{enable/disable}_clk in s3c_rtc_setfreq()
2016-07-05 9:58 [PATCH v2 1/2] rtc: s3c: Remove unnecessary call to disable already disabled clock Alim Akhtar
@ 2016-07-05 9:58 ` Alim Akhtar
2016-07-19 15:50 ` Alexandre Belloni
2016-07-19 15:50 ` [PATCH v2 1/2] rtc: s3c: Remove unnecessary call to disable already disabled clock Alexandre Belloni
1 sibling, 1 reply; 4+ messages in thread
From: Alim Akhtar @ 2016-07-05 9:58 UTC (permalink / raw)
To: rtc-linux, linux-kernel
Cc: alexandre.belloni, k.kozlowski, javier, pankaj.dubey,
alim.akhtar, stable
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")
Cc: <stable@vger.kernel.org>
Signed-off-by: Alim Akhtar <alim.akhtar@samsung.com>
Reviewed-by: Krzysztof Kozlowski <k.kozlowski@samsung.com>
Reviewed-by: Pankaj Dubey <pankaj.dubey@samsung.com>
Tested-by: Pankaj Dubey <pankaj.dubey@samsung.com>
---
drivers/rtc/rtc-s3c.c | 2 ++
1 file changed, 2 insertions(+)
* Changes from v1
-updated commit message as suggested by Krzysztof.
-updated reviewed-by, tested-by tags
diff --git a/drivers/rtc/rtc-s3c.c b/drivers/rtc/rtc-s3c.c
index b083840..1168814 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;
}
--
1.7.10.4
^ permalink raw reply related [flat|nested] 4+ messages in thread
* Re: [PATCH v2 1/2] rtc: s3c: Remove unnecessary call to disable already disabled clock
2016-07-05 9:58 [PATCH v2 1/2] rtc: s3c: Remove unnecessary call to disable already disabled clock Alim Akhtar
2016-07-05 9:58 ` [PATCH v2 2/2] rtc: s3c: Add s3c_rtc_{enable/disable}_clk in s3c_rtc_setfreq() Alim Akhtar
@ 2016-07-19 15:50 ` Alexandre Belloni
1 sibling, 0 replies; 4+ messages in thread
From: Alexandre Belloni @ 2016-07-19 15:50 UTC (permalink / raw)
To: Alim Akhtar; +Cc: rtc-linux, linux-kernel, k.kozlowski, javier, pankaj.dubey
On 05/07/2016 at 15:28:52 +0530, Alim Akhtar wrote :
> At the end of s3c_rtc_probe(), s3c_rtc_disable_clk() being called with rtc
> clock already disabled (by s3c_rtc_gettime()), which looks extra and
> unnecessary call. Lets clean it up.
>
> Signed-off-by: Alim Akhtar <alim.akhtar@samsung.com>
> Reviewed-by: Krzysztof Kozlowski <k.kozlowski@samsung.com>
> Reviewed-by: Pankaj Dubey <pankaj.dubey@samsung.com>
> Tested-by: Pankaj Dubey <pankaj.dubey@samsung.com>
> ---
> drivers/rtc/rtc-s3c.c | 2 --
> 1 file changed, 2 deletions(-)
>
Applied, thanks.
--
Alexandre Belloni, Free Electrons
Embedded Linux and Kernel engineering
http://free-electrons.com
^ permalink raw reply [flat|nested] 4+ messages in thread
* Re: [PATCH v2 2/2] rtc: s3c: Add s3c_rtc_{enable/disable}_clk in s3c_rtc_setfreq()
2016-07-05 9:58 ` [PATCH v2 2/2] rtc: s3c: Add s3c_rtc_{enable/disable}_clk in s3c_rtc_setfreq() Alim Akhtar
@ 2016-07-19 15:50 ` Alexandre Belloni
0 siblings, 0 replies; 4+ messages in thread
From: Alexandre Belloni @ 2016-07-19 15:50 UTC (permalink / raw)
To: Alim Akhtar
Cc: rtc-linux, linux-kernel, k.kozlowski, javier, pankaj.dubey, stable
On 05/07/2016 at 15:28:53 +0530, Alim Akhtar wrote :
> 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")
>
> Cc: <stable@vger.kernel.org>
> Signed-off-by: Alim Akhtar <alim.akhtar@samsung.com>
> Reviewed-by: Krzysztof Kozlowski <k.kozlowski@samsung.com>
> Reviewed-by: Pankaj Dubey <pankaj.dubey@samsung.com>
> Tested-by: Pankaj Dubey <pankaj.dubey@samsung.com>
> ---
> drivers/rtc/rtc-s3c.c | 2 ++
> 1 file changed, 2 insertions(+)
>
Applied, thanks.
--
Alexandre Belloni, Free Electrons
Embedded Linux and Kernel engineering
http://free-electrons.com
^ permalink raw reply [flat|nested] 4+ messages in thread
end of thread, other threads:[~2016-07-19 15:50 UTC | newest]
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2016-07-05 9:58 [PATCH v2 1/2] rtc: s3c: Remove unnecessary call to disable already disabled clock Alim Akhtar
2016-07-05 9:58 ` [PATCH v2 2/2] rtc: s3c: Add s3c_rtc_{enable/disable}_clk in s3c_rtc_setfreq() Alim Akhtar
2016-07-19 15:50 ` Alexandre Belloni
2016-07-19 15:50 ` [PATCH v2 1/2] rtc: s3c: Remove unnecessary call to disable already disabled clock Alexandre Belloni
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