linux-toradex.git/drivers/clocksource/sun4i_timer.c, branch v3.12.43

clockevent: sun4i: Fix race condition in the probe code

2014-12-06T14:14:51+00:00

commit 6bab4a8a1888729f17f4923cc5867e4674f66333 upstream.

The interrupts were activated and the handler registered before the clockevent
was registered in the probe function.

The interrupt handler, however, was making the assumption that the clockevent
device was registered.

That could cause a null pointer dereference if the timer interrupt was firing
during this narrow window.

Fix that by moving the clockevent registration before the interrupt is enabled.

Reported-by: Roman Byshko 
Signed-off-by: Maxime Ripard 
Signed-off-by: Daniel Lezcano 
Signed-off-by: Jiri Slaby

clocksource: sun4i: Fix bug when switching from periodic to oneshot modes

2013-07-18T13:27:21+00:00

The interval was firing at was set up at probe time, and only changed in
the set_next_event, and never changed back, which is not really what is
expected.

When enabling the periodic mode, now set an interval to tick every
jiffy.

Signed-off-by: Maxime Ripard 
Signed-off-by: Daniel Lezcano

clocksource: sun4i: Cleanup parent clock setup

2013-07-18T13:27:20+00:00

The current bring-up code for the timer was overly complicated. The only
thing we need is actually which clock we want to use as source and
that's pretty much all. Let's keep it that way.

Signed-off-by: Maxime Ripard 
Signed-off-by: Daniel Lezcano

clocksource: sun4i: Remove TIMER_SCAL variable

2013-07-18T13:27:19+00:00

The prescaler is only used when using the internal low frequency
oscillator (at 32kHz). Since we're using the higher frequency oscillator
at 24MHz, we can just remove it.

Signed-off-by: Maxime Ripard 
Signed-off-by: Daniel Lezcano

clocksource: sun4i: Factor out some timer code

2013-07-18T13:27:18+00:00

The set_next_event and set_mode callbacks share a lot of common code we
can easily factor to avoid duplication and mistakes.

Signed-off-by: Maxime Ripard 
Signed-off-by: Daniel Lezcano

clocksource: sun4i: Fix the next event code

2013-07-18T13:27:17+00:00

The next_event logic was setting the next interval to fire in the
current timer value instead of the interval value register, which is
obviously wrong.

Plus, the logic to set the actual value was wrong as well: the interval
register can only be modified when the timer is disabled, and then
enable it back, otherwise, it'll have no effect. Fix this logic as well
since that code couldn't possibly work.

Signed-off-by: Maxime Ripard 
Signed-off-by: Daniel Lezcano

clocksource: sun4i: Don't forget to enable the clock we use

2013-07-18T13:27:16+00:00

Even if in our case, this clock was non-gatable, used as a parent clock
for several IPs, it still is a good idea to enable it.

Signed-off-by: Maxime Ripard 
Signed-off-by: Daniel Lezcano

clocksource: sun4i: Add clocksource and sched clock drivers

2013-07-18T13:27:15+00:00

Use the second timer found on the Allwinner SoCs as a clock source and
sched clock, that were both not used yet on these platforms.

Signed-off-by: Maxime Ripard 
Signed-off-by: Daniel Lezcano

clocksource: sun4i: rename AUTORELOAD define to RELOAD

2013-07-18T13:27:14+00:00

The name AUTORELOAD was actually pretty bad since it doesn't make the
register reload the previous interval when it expires, but setting this
value pushes the new programmed interval to the internal timer counter.
Rename it to RELOAD instead.

Signed-off-by: Maxime Ripard 
Signed-off-by: Daniel Lezcano

clocksource: sun4i: Wrap macros arguments in parenthesis

2013-07-18T13:27:13+00:00

The macros were not using parenthesis to escape the arguments passed to
them. It is pretty unsafe, so add those parenthesis.

Signed-off-by: Maxime Ripard 
Signed-off-by: Daniel Lezcano