[RFC][PATCH 2/3] clocksource: scx200_hrt: Convert scx200 to use clocksource_register_hz

From: John Stultz
Date: Mon Jan 23 2012 - 19:07:33 EST


Converts the scx200 clocksource to using clocksource_register_hz.

This wasn't a straight conversion, so would like some extra review
by the maintainers.

CC: Jim Cromie <jim.cromie@xxxxxxxxx>
Signed-off-by: John Stultz <john.stultz@xxxxxxxxxx>
---
drivers/clocksource/scx200_hrt.c | 19 ++++++-------------
1 files changed, 6 insertions(+), 13 deletions(-)

diff --git a/drivers/clocksource/scx200_hrt.c b/drivers/clocksource/scx200_hrt.c
index 27f4d96..24f884c 100644
--- a/drivers/clocksource/scx200_hrt.c
+++ b/drivers/clocksource/scx200_hrt.c
@@ -49,9 +49,6 @@ static cycle_t read_hrt(struct clocksource *cs)
return (cycle_t) inl(scx200_cb_base + SCx200_TIMER_OFFSET);
}

-#define HRT_SHIFT_1 22
-#define HRT_SHIFT_27 26
-
static struct clocksource cs_hrt = {
.name = "scx200_hrt",
.rating = 250,
@@ -63,6 +60,7 @@ static struct clocksource cs_hrt = {

static int __init init_hrt_clocksource(void)
{
+ u32 freq;
/* Make sure scx200 has initialized the configuration block */
if (!scx200_cb_present())
return -ENODEV;
@@ -79,19 +77,14 @@ static int __init init_hrt_clocksource(void)
outb(HR_TMEN | (mhz27 ? HR_TMCLKSEL : 0),
scx200_cb_base + SCx200_TMCNFG_OFFSET);

- if (mhz27) {
- cs_hrt.shift = HRT_SHIFT_27;
- cs_hrt.mult = clocksource_hz2mult((HRT_FREQ + ppm) * 27,
- cs_hrt.shift);
- } else {
- cs_hrt.shift = HRT_SHIFT_1;
- cs_hrt.mult = clocksource_hz2mult(HRT_FREQ + ppm,
- cs_hrt.shift);
- }
+ freq = (HRT_FREQ + ppm);
+ if (mhz27)
+ freq *= 27;
+
printk(KERN_INFO "enabling scx200 high-res timer (%s MHz +%d ppm)\n",
mhz27 ? "27":"1", ppm);

- return clocksource_register(&cs_hrt);
+ return clocksource_register_hz(&cs_hrt, freq);
}

module_init(init_hrt_clocksource);
--
1.7.3.2.146.gca209

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