diff options
Diffstat (limited to 'drivers/pwm/pwm-bcm2835.c')
| -rw-r--r-- | drivers/pwm/pwm-bcm2835.c | 19 |
1 files changed, 10 insertions, 9 deletions
diff --git a/drivers/pwm/pwm-bcm2835.c b/drivers/pwm/pwm-bcm2835.c index f6fe0b922e1e..91e24f01b54e 100644 --- a/drivers/pwm/pwm-bcm2835.c +++ b/drivers/pwm/pwm-bcm2835.c @@ -21,7 +21,7 @@ #define PERIOD(x) (((x) * 0x10) + 0x10) #define DUTY(x) (((x) * 0x10) + 0x14) -#define MIN_PERIOD 108 /* 9.2 MHz max. PWM clock */ +#define PERIOD_MIN 0x2 struct bcm2835_pwm { struct pwm_chip chip; @@ -64,6 +64,7 @@ static int bcm2835_pwm_config(struct pwm_chip *chip, struct pwm_device *pwm, struct bcm2835_pwm *pc = to_bcm2835_pwm(chip); unsigned long rate = clk_get_rate(pc->clk); unsigned long scaler; + u32 period; if (!rate) { dev_err(pc->dev, "failed to get clock rate\n"); @@ -71,17 +72,14 @@ static int bcm2835_pwm_config(struct pwm_chip *chip, struct pwm_device *pwm, } scaler = DIV_ROUND_CLOSEST(NSEC_PER_SEC, rate); + period = DIV_ROUND_CLOSEST(period_ns, scaler); - if (period_ns <= MIN_PERIOD) { - dev_err(pc->dev, "period %d not supported, minimum %d\n", - period_ns, MIN_PERIOD); + if (period < PERIOD_MIN) return -EINVAL; - } writel(DIV_ROUND_CLOSEST(duty_ns, scaler), pc->base + DUTY(pwm->hwpwm)); - writel(DIV_ROUND_CLOSEST(period_ns, scaler), - pc->base + PERIOD(pwm->hwpwm)); + writel(period, pc->base + PERIOD(pwm->hwpwm)); return 0; } @@ -155,8 +153,11 @@ static int bcm2835_pwm_probe(struct platform_device *pdev) pc->clk = devm_clk_get(&pdev->dev, NULL); if (IS_ERR(pc->clk)) { - dev_err(&pdev->dev, "clock not found: %ld\n", PTR_ERR(pc->clk)); - return PTR_ERR(pc->clk); + ret = PTR_ERR(pc->clk); + if (ret != -EPROBE_DEFER) + dev_err(&pdev->dev, "clock not found: %d\n", ret); + + return ret; } ret = clk_prepare_enable(pc->clk); |