diff options
| -rw-r--r-- | arch/arm/plat-s3c/pwm-clock.c | 51 |
1 files changed, 47 insertions, 4 deletions
diff --git a/arch/arm/plat-s3c/pwm-clock.c b/arch/arm/plat-s3c/pwm-clock.c index 3fad68a1e6b..b0fcbc1fb64 100644 --- a/arch/arm/plat-s3c/pwm-clock.c +++ b/arch/arm/plat-s3c/pwm-clock.c @@ -73,7 +73,7 @@ * tclk -------------------------/ */ -static unsigned long clk_pwm_scaler_getrate(struct clk *clk) +static unsigned long clk_pwm_scaler_get_rate(struct clk *clk) { unsigned long tcfg0 = __raw_readl(S3C2410_TCFG0); @@ -87,18 +87,61 @@ static unsigned long clk_pwm_scaler_getrate(struct clk *clk) return clk_get_rate(clk->parent) / (tcfg0 + 1); } -/* TODO - add set rate calls. */ +static unsigned long clk_pwm_scaler_round_rate(struct clk *clk, + unsigned long rate) +{ + unsigned long parent_rate = clk_get_rate(clk->parent); + unsigned long divisor = parent_rate / rate; + + if (divisor > 256) + divisor = 256; + else if (divisor < 2) + divisor = 2; + + return parent_rate / divisor; +} + +static int clk_pwm_scaler_set_rate(struct clk *clk, unsigned long rate) +{ + unsigned long round = clk_pwm_scaler_round_rate(clk, rate); + unsigned long tcfg0; + unsigned long divisor; + unsigned long flags; + + divisor = clk_get_rate(clk->parent) / round; + divisor--; + + local_irq_save(flags); + tcfg0 = __raw_readl(S3C2410_TCFG0); + + if (clk->id == 1) { + tcfg0 &= ~S3C2410_TCFG_PRESCALER1_MASK; + tcfg0 |= divisor << S3C2410_TCFG_PRESCALER1_SHIFT; + } else { + tcfg0 &= ~S3C2410_TCFG_PRESCALER0_MASK; + tcfg0 |= divisor; + } + + __raw_writel(tcfg0, S3C2410_TCFG0); + local_irq_restore(flags); + + return 0; +} static struct clk clk_timer_scaler[] = { [0] = { .name = "pwm-scaler0", .id = -1, - .get_rate = clk_pwm_scaler_getrate, + .get_rate = clk_pwm_scaler_get_rate, + .set_rate = clk_pwm_scaler_set_rate, + .round_rate = clk_pwm_scaler_round_rate, }, [1] = { .name = "pwm-scaler1", .id = -1, - .get_rate = clk_pwm_scaler_getrate, + .get_rate = clk_pwm_scaler_get_rate, + .set_rate = clk_pwm_scaler_set_rate, + .round_rate = clk_pwm_scaler_round_rate, }, }; |