[PATCH 24/41] clocksource: tcb_clksrc: Migrate to new 'set-state' interface

From: Viresh Kumar
Date: Thu Jun 18 2015 - 07:03:20 EST


Migrate tcb_clksrc driver to the new 'set-state' interface provided by
clockevents core, the earlier 'set-mode' interface is marked obsolete
now.

This also enables us to implement callbacks for new states of clockevent
devices, for example: ONESHOT_STOPPED.

Cc: Nicolas Ferre <nicolas.ferre@xxxxxxxxx>
Signed-off-by: Viresh Kumar <viresh.kumar@xxxxxxxxxx>
---
drivers/clocksource/tcb_clksrc.c | 93 ++++++++++++++++++++++------------------
1 file changed, 51 insertions(+), 42 deletions(-)

diff --git a/drivers/clocksource/tcb_clksrc.c b/drivers/clocksource/tcb_clksrc.c
index 8bdbc45c6dad..d28d2fe798d5 100644
--- a/drivers/clocksource/tcb_clksrc.c
+++ b/drivers/clocksource/tcb_clksrc.c
@@ -91,55 +91,62 @@ static struct tc_clkevt_device *to_tc_clkevt(struct clock_event_device *clkevt)
*/
static u32 timer_clock;

-static void tc_mode(enum clock_event_mode m, struct clock_event_device *d)
+static int tc_shutdown(struct clock_event_device *d)
{
struct tc_clkevt_device *tcd = to_tc_clkevt(d);
void __iomem *regs = tcd->regs;

- if (tcd->clkevt.mode == CLOCK_EVT_MODE_PERIODIC
- || tcd->clkevt.mode == CLOCK_EVT_MODE_ONESHOT) {
- __raw_writel(0xff, regs + ATMEL_TC_REG(2, IDR));
- __raw_writel(ATMEL_TC_CLKDIS, regs + ATMEL_TC_REG(2, CCR));
- clk_disable(tcd->clk);
- }
+ __raw_writel(0xff, regs + ATMEL_TC_REG(2, IDR));
+ __raw_writel(ATMEL_TC_CLKDIS, regs + ATMEL_TC_REG(2, CCR));
+ clk_disable(tcd->clk);

- switch (m) {
+ return 0;
+}

- /* By not making the gentime core emulate periodic mode on top
- * of oneshot, we get lower overhead and improved accuracy.
- */
- case CLOCK_EVT_MODE_PERIODIC:
- clk_enable(tcd->clk);
+static int tc_set_oneshot(struct clock_event_device *d)
+{
+ struct tc_clkevt_device *tcd = to_tc_clkevt(d);
+ void __iomem *regs = tcd->regs;

- /* slow clock, count up to RC, then irq and restart */
- __raw_writel(timer_clock
- | ATMEL_TC_WAVE | ATMEL_TC_WAVESEL_UP_AUTO,
- regs + ATMEL_TC_REG(2, CMR));
- __raw_writel((32768 + HZ/2) / HZ, tcaddr + ATMEL_TC_REG(2, RC));
+ if (clockevent_state_oneshot(d) || clockevent_state_periodic(d))
+ tc_shutdown(d);

- /* Enable clock and interrupts on RC compare */
- __raw_writel(ATMEL_TC_CPCS, regs + ATMEL_TC_REG(2, IER));
+ clk_enable(tcd->clk);

- /* go go gadget! */
- __raw_writel(ATMEL_TC_CLKEN | ATMEL_TC_SWTRG,
- regs + ATMEL_TC_REG(2, CCR));
- break;
+ /* slow clock, count up to RC, then irq and stop */
+ __raw_writel(timer_clock | ATMEL_TC_CPCSTOP | ATMEL_TC_WAVE |
+ ATMEL_TC_WAVESEL_UP_AUTO, regs + ATMEL_TC_REG(2, CMR));
+ __raw_writel(ATMEL_TC_CPCS, regs + ATMEL_TC_REG(2, IER));

- case CLOCK_EVT_MODE_ONESHOT:
- clk_enable(tcd->clk);
+ /* set_next_event() configures and starts the timer */
+ return 0;
+}

- /* slow clock, count up to RC, then irq and stop */
- __raw_writel(timer_clock | ATMEL_TC_CPCSTOP
- | ATMEL_TC_WAVE | ATMEL_TC_WAVESEL_UP_AUTO,
- regs + ATMEL_TC_REG(2, CMR));
- __raw_writel(ATMEL_TC_CPCS, regs + ATMEL_TC_REG(2, IER));
+static int tc_set_periodic(struct clock_event_device *d)
+{
+ struct tc_clkevt_device *tcd = to_tc_clkevt(d);
+ void __iomem *regs = tcd->regs;

- /* set_next_event() configures and starts the timer */
- break;
+ if (clockevent_state_oneshot(d) || clockevent_state_periodic(d))
+ tc_shutdown(d);

- default:
- break;
- }
+ /* By not making the gentime core emulate periodic mode on top
+ * of oneshot, we get lower overhead and improved accuracy.
+ */
+ clk_enable(tcd->clk);
+
+ /* slow clock, count up to RC, then irq and restart */
+ __raw_writel(timer_clock | ATMEL_TC_WAVE | ATMEL_TC_WAVESEL_UP_AUTO,
+ regs + ATMEL_TC_REG(2, CMR));
+ __raw_writel((32768 + HZ / 2) / HZ, tcaddr + ATMEL_TC_REG(2, RC));
+
+ /* Enable clock and interrupts on RC compare */
+ __raw_writel(ATMEL_TC_CPCS, regs + ATMEL_TC_REG(2, IER));
+
+ /* go go gadget! */
+ __raw_writel(ATMEL_TC_CLKEN | ATMEL_TC_SWTRG, regs +
+ ATMEL_TC_REG(2, CCR));
+ return 0;
}

static int tc_next_event(unsigned long delta, struct clock_event_device *d)
@@ -154,13 +161,15 @@ static int tc_next_event(unsigned long delta, struct clock_event_device *d)

static struct tc_clkevt_device clkevt = {
.clkevt = {
- .name = "tc_clkevt",
- .features = CLOCK_EVT_FEAT_PERIODIC
- | CLOCK_EVT_FEAT_ONESHOT,
+ .name = "tc_clkevt",
+ .features = CLOCK_EVT_FEAT_PERIODIC |
+ CLOCK_EVT_FEAT_ONESHOT,
/* Should be lower than at91rm9200's system timer */
- .rating = 125,
- .set_next_event = tc_next_event,
- .set_mode = tc_mode,
+ .rating = 125,
+ .set_next_event = tc_next_event,
+ .set_state_shutdown = tc_shutdown,
+ .set_state_periodic = tc_set_periodic,
+ .set_state_oneshot = tc_set_oneshot,
},
};

--
2.4.0

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