clocksource: samsung_pwm_timer: Handle suspend/resume correctly
Current suspend/resume handling of the driver was broken, because:
- periodic timer was being enabled in CLOCK_EVT_MODE_RESUME mode, which
does not seem to be correct behavior looking at other platforms,
- PWM divisors need to be restored, but they were not,
- clockevent interrupt mask needs to be restored, but it was not,
- clocksource was being restored in clockevent resume callback.
This patch fixes issues mentioned above, making suspend/resume handling
in the driver correct.
Signed-off-by: Tomasz Figa <tomasz.figa@gmail.com>
Reviewed-by: Sylwester Nawrocki <s.nawrocki@samsung.com>
Tested-by: Heiko Stuebner <heiko@sntech.de>
Tested-by: Mark Brown <broonie@linaro.org>
Tested-by: Sylwester Nawrocki <sylvester.nawrocki@gmail.com>
Acked-by: Arnd Bergmann <arnd@arndb.de>
Acked-by: Daniel Lezcano <daniel.lezcano@linaro.org>
diff --git a/drivers/clocksource/samsung_pwm_timer.c b/drivers/clocksource/samsung_pwm_timer.c
index b3112dc..ac60f8b 100644
--- a/drivers/clocksource/samsung_pwm_timer.c
+++ b/drivers/clocksource/samsung_pwm_timer.c
@@ -207,17 +207,6 @@
return 0;
}
-static void samsung_timer_resume(void)
-{
- /* event timer restart */
- samsung_time_setup(pwm.event_id, pwm.clock_count_per_tick - 1);
- samsung_time_start(pwm.event_id, true);
-
- /* source timer restart */
- samsung_time_setup(pwm.source_id, pwm.tcnt_max);
- samsung_time_start(pwm.source_id, true);
-}
-
static void samsung_set_mode(enum clock_event_mode mode,
struct clock_event_device *evt)
{
@@ -234,20 +223,29 @@
case CLOCK_EVT_MODE_UNUSED:
case CLOCK_EVT_MODE_SHUTDOWN:
- break;
-
case CLOCK_EVT_MODE_RESUME:
- samsung_timer_resume();
break;
}
}
+static void samsung_clockevent_resume(struct clock_event_device *cev)
+{
+ samsung_timer_set_prescale(pwm.event_id, pwm.tscaler_div);
+ samsung_timer_set_divisor(pwm.event_id, pwm.tdiv);
+
+ if (pwm.variant.has_tint_cstat) {
+ u32 mask = (1 << pwm.event_id);
+ writel(mask | (mask << 5), pwm.base + REG_TINT_CSTAT);
+ }
+}
+
static struct clock_event_device time_event_device = {
.name = "samsung_event_timer",
.features = CLOCK_EVT_FEAT_PERIODIC | CLOCK_EVT_FEAT_ONESHOT,
.rating = 200,
.set_next_event = samsung_set_next_event,
.set_mode = samsung_set_mode,
+ .resume = samsung_clockevent_resume,
};
static irqreturn_t samsung_clock_event_isr(int irq, void *dev_id)
@@ -298,6 +296,20 @@
}
}
+static void samsung_clocksource_suspend(struct clocksource *cs)
+{
+ samsung_time_stop(pwm.source_id);
+}
+
+static void samsung_clocksource_resume(struct clocksource *cs)
+{
+ samsung_timer_set_prescale(pwm.source_id, pwm.tscaler_div);
+ samsung_timer_set_divisor(pwm.source_id, pwm.tdiv);
+
+ samsung_time_setup(pwm.source_id, pwm.tcnt_max);
+ samsung_time_start(pwm.source_id, true);
+}
+
static cycle_t samsung_clocksource_read(struct clocksource *c)
{
return ~readl_relaxed(pwm.source_reg);
@@ -307,6 +319,8 @@
.name = "samsung_clocksource_timer",
.rating = 250,
.read = samsung_clocksource_read,
+ .suspend = samsung_clocksource_suspend,
+ .resume = samsung_clocksource_resume,
.flags = CLOCK_SOURCE_IS_CONTINUOUS,
};