[PATCH] ARM AT91: clocksource tcb_clksrc.c: make tc_mode interrupt safe

[daniel.lezcano@linaro.org (Daniel Lezcano)]

On 05/22/2014 06:33 PM, Nicolas Ferre wrote:
> On 22/05/2014 15:32, Alexandre Belloni :
>> On 08/05/2014 at 12:06:25 +0200, David Jander wrote :
>>> tc_mode() can be called from interrupt context and thus must not call
>>> clk_*prepare*() functions.
>>>
>>> Signed-off-by: David Jander <david@protonic.nl>
>>
>> Acked-by: Alexandre Belloni <alexandre.belloni@free-electrons.com>
>
> Ok, indeed. We keep the clocks prepared for the system lifetime.
>
> Acked-by: Nicolas Ferre <nicolas.ferre@atmel.com>
>
> Daniel, can you please take this fix (do you want me to re-send it)?

It is ok, I applied it as a 3.15 fix.

Thanks

   -- Daniel

>>> ---
>>>   drivers/clocksource/tcb_clksrc.c | 8 ++++----
>>>   1 file changed, 4 insertions(+), 4 deletions(-)
>>>
>>> diff --git a/drivers/clocksource/tcb_clksrc.c b/drivers/clocksource/tcb_clksrc.c
>>> index 00fdd11..a8d7ea1 100644
>>> --- a/drivers/clocksource/tcb_clksrc.c
>>> +++ b/drivers/clocksource/tcb_clksrc.c
>>> @@ -100,7 +100,7 @@ static void tc_mode(enum clock_event_mode m, struct clock_event_device *d)
>>>   			|| tcd->clkevt.mode == CLOCK_EVT_MODE_ONESHOT) {
>>>   		__raw_writel(0xff, regs + ATMEL_TC_REG(2, IDR));
>>>   		__raw_writel(ATMEL_TC_CLKDIS, regs + ATMEL_TC_REG(2, CCR));
>>> -		clk_disable_unprepare(tcd->clk);
>>> +		clk_disable(tcd->clk);
>>>   	}
>>>
>>>   	switch (m) {
>>> @@ -109,7 +109,7 @@ static void tc_mode(enum clock_event_mode m, struct clock_event_device *d)
>>>   	 * of oneshot, we get lower overhead and improved accuracy.
>>>   	 */
>>>   	case CLOCK_EVT_MODE_PERIODIC:
>>> -		clk_prepare_enable(tcd->clk);
>>> +		clk_enable(tcd->clk);
>>>
>>>   		/* slow clock, count up to RC, then irq and restart */
>>>   		__raw_writel(timer_clock
>>> @@ -126,7 +126,7 @@ static void tc_mode(enum clock_event_mode m, struct clock_event_device *d)
>>>   		break;
>>>
>>>   	case CLOCK_EVT_MODE_ONESHOT:
>>> -		clk_prepare_enable(tcd->clk);
>>> +		clk_enable(tcd->clk);
>>>
>>>   		/* slow clock, count up to RC, then irq and stop */
>>>   		__raw_writel(timer_clock | ATMEL_TC_CPCSTOP
>>> @@ -194,7 +194,7 @@ static int __init setup_clkevents(struct atmel_tc *tc, int clk32k_divisor_idx)
>>>   	ret = clk_prepare_enable(t2_clk);
>>>   	if (ret)
>>>   		return ret;
>>> -	clk_disable_unprepare(t2_clk);
>>> +	clk_disable(t2_clk);
>>>
>>>   	clkevt.regs = tc->regs;
>>>   	clkevt.clk = t2_clk;
>>> --
>>> 1.9.1
>>>
>>>
>>> _______________________________________________
>>> linux-arm-kernel mailing list
>>> linux-arm-kernel at lists.infradead.org
>>> http://lists.infradead.org/mailman/listinfo/linux-arm-kernel
>>
>
>


-- 
  <http://www.linaro.org/> Linaro.org ? Open source software for ARM SoCs

Follow Linaro:  <http://www.facebook.com/pages/Linaro> Facebook |
<http://twitter.com/#!/linaroorg> Twitter |
<http://www.linaro.org/linaro-blog/> Blog