clocksource/drivers/h8300_timer8: Retrieve the clock rate at init time

The current code retrieves the rate value when the timer is enabled which
occurs each time a timer is re-armed. Except if the clock frequency has changed
magically I don't see why this should be done each time.

Retrieve the clock rate value at init time only.

Signed-off-by: Daniel Lezcano <daniel.lezcano@linaro.org>

diff --git a/drivers/clocksource/h8300_timer8.c b/drivers/clocksource/h8300_timer8.c
index 24d91b1a5d5cc62fa9b3bdf9728fbd7a881ab832..187c41619b13f69f9f616cb8f75ffc8a0bcadfb2 100644 (file)
--- a/drivers/clocksource/h8300_timer8.c
+++ b/drivers/clocksource/h8300_timer8.c
@@ -34,7 +34,6 @@ struct timer8_priv {
        unsigned long flags;
        unsigned int rate;
        unsigned int tcora;
-       struct clk *pclk;
 };
 
 static unsigned long timer8_get_counter(struct timer8_priv *p)
@@ -92,7 +91,6 @@ static void timer8_set_next(struct timer8_priv *p, unsigned long delta)
 
 static int timer8_enable(struct timer8_priv *p)
 {
-       p->rate = clk_get_rate(p->pclk) / SCALE;
        ctrl_outw(0xffff, p->mapbase + TCORA);
        ctrl_outw(0x0000, p->mapbase + _8TCNT);
        ctrl_outw(0x0c02, p->mapbase + _8TCR);
@@ -102,16 +100,15 @@ static int timer8_enable(struct timer8_priv *p)
 
 static int timer8_start(struct timer8_priv *p)
 {
-       int ret = 0;
+       int ret;
 
-       if (!(p->flags & FLAG_STARTED))
-               ret = timer8_enable(p);
+       if ((p->flags & FLAG_STARTED))
+               return 0;
 
-       if (ret)
-               goto out;
-       p->flags |= FLAG_STARTED;
+       ret = timer8_enable(p);
+       if (!ret)
+               p->flags |= FLAG_STARTED;
 
- out:
        return ret;
 }
 
@@ -217,7 +214,12 @@ static void __init h8300_8timer_init(struct device_node *node)
        }
 
        timer8_priv.mapbase = (unsigned long)base;
-       timer8_priv.pclk = clk;
+
+       rate = clk_get_rate(clk) / SCALE;
+       if (!rate) {
+               pr_err("Failed to get rate for the clocksource\n");
+               goto unmap_reg;
+       }
 
        ret = request_irq(irq, timer8_interrupt,
                          IRQF_TIMER, timer8_priv.ced.name, &timer8_priv);
@@ -225,10 +227,10 @@ static void __init h8300_8timer_init(struct device_node *node)
                pr_err("failed to request irq %d for clockevent\n", irq);
                goto unmap_reg;
        }
-       rate = clk_get_rate(clk) / SCALE;
+
        clockevents_config_and_register(&timer8_priv.ced, rate, 1, 0x0000ffff);
-       return;
 
+       return;
 unmap_reg:
        iounmap(base);
 free_clk: