clocksource: convert W90x900 24-bit down counting clocksource

Convert the W90x900 24-bit down-counting clocksource to the generic
mmio clocksource infrastructure

Acked-by: Wan ZongShun <mcuos.com@gmail.com>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>

1 files changed, 2 insertions, 15 deletions

diff --git a/arch/arm/mach-w90x900/time.c b/arch/arm/mach-w90x900/time.c
index 4b089cb930dc..a2c4e2d0a0d4 100644
--- a/arch/arm/mach-w90x900/time.c
+++ b/arch/arm/mach-w90x900/time.c
@@ -43,7 +43,6 @@
 #define PRESCALE        0x63 /* Divider = prescale + 1 */
 
 #define TDR_SHIFT       24
-#define TDR_MASK        ((1 << TDR_SHIFT) - 1)
 
 static unsigned int timer0_load;
 
@@ -143,19 +142,6 @@ static void __init nuc900_clockevents_init(void)
         clockevents_register_device(&nuc900_clockevent_device);
 }
 
-static cycle_t nuc900_get_cycles(struct clocksource *cs)
-{
-        return (~__raw_readl(REG_TDR1)) & TDR_MASK;
-}
-
-static struct clocksource clocksource_nuc900 = {
-        .name   = "nuc900-timer1",
-        .rating = 200,
-        .read   = nuc900_get_cycles,
-        .mask   = CLOCKSOURCE_MASK(TDR_SHIFT),
-        .flags  = CLOCK_SOURCE_IS_CONTINUOUS,
-};
-
 static void __init nuc900_clocksource_init(void)
 {
         unsigned int val;
@@ -175,7 +161,8 @@ static void __init nuc900_clocksource_init(void)
         val |= (COUNTEN | PERIOD | PRESCALE);
         __raw_writel(val, REG_TCSR1);
 
-        clocksource_register_hz(&clocksource_nuc900, rate);
+        clocksource_mmio_init(REG_TDR1, "nuc900-timer1", rate, 200,
+                TDR_SHIFT, clocksource_mmio_readl_down);
 }
 
 static void __init nuc900_timer_init(void)