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authorStefan Wahren <stefan.wahren@i2se.com>2015-12-01 22:55:39 +0000
committerThierry Reding <thierry.reding@gmail.com>2015-12-16 16:44:36 +0100
commitebe88b6ae41ff8f2b48608b6019c4341aa24bcea (patch)
tree33c3e4590e449e3988d58d6d426853fdf920d72d /drivers/pwm
parentc7b91b33cf446ec09eedf4594cff8d7b85ef6870 (diff)
downloadblackbird-op-linux-ebe88b6ae41ff8f2b48608b6019c4341aa24bcea.tar.gz
blackbird-op-linux-ebe88b6ae41ff8f2b48608b6019c4341aa24bcea.zip
pwm: bcm2835: Calculate scaler in ->config()
Currently pwm-bcm2835 assumes a fixed clock rate and stores the resulting scaler in the driver structure. But with the upcoming PWM clock support for clk-bcm2835 the rate could change, so calculate the scaler in the ->config() callback. Signed-off-by: Stefan Wahren <stefan.wahren@i2se.com> Reviewed-by: Eric Anholt <eric@anholt.net> Signed-off-by: Thierry Reding <thierry.reding@gmail.com>
Diffstat (limited to 'drivers/pwm')
-rw-r--r--drivers/pwm/pwm-bcm2835.c8
1 files changed, 3 insertions, 5 deletions
diff --git a/drivers/pwm/pwm-bcm2835.c b/drivers/pwm/pwm-bcm2835.c
index b4c7f956b6fa..174cca92f690 100644
--- a/drivers/pwm/pwm-bcm2835.c
+++ b/drivers/pwm/pwm-bcm2835.c
@@ -29,7 +29,6 @@
struct bcm2835_pwm {
struct pwm_chip chip;
struct device *dev;
- unsigned long scaler;
void __iomem *base;
struct clk *clk;
};
@@ -66,6 +65,7 @@ static int bcm2835_pwm_config(struct pwm_chip *chip, struct pwm_device *pwm,
int duty_ns, int period_ns)
{
struct bcm2835_pwm *pc = to_bcm2835_pwm(chip);
+ unsigned long scaler = NSEC_PER_SEC / clk_get_rate(pc->clk);
if (period_ns <= MIN_PERIOD) {
dev_err(pc->dev, "period %d not supported, minimum %d\n",
@@ -73,8 +73,8 @@ static int bcm2835_pwm_config(struct pwm_chip *chip, struct pwm_device *pwm,
return -EINVAL;
}
- writel(duty_ns / pc->scaler, pc->base + DUTY(pwm->hwpwm));
- writel(period_ns / pc->scaler, pc->base + PERIOD(pwm->hwpwm));
+ writel(duty_ns / scaler, pc->base + DUTY(pwm->hwpwm));
+ writel(period_ns / scaler, pc->base + PERIOD(pwm->hwpwm));
return 0;
}
@@ -156,8 +156,6 @@ static int bcm2835_pwm_probe(struct platform_device *pdev)
if (ret)
return ret;
- pc->scaler = NSEC_PER_SEC / clk_get_rate(pc->clk);
-
pc->chip.dev = &pdev->dev;
pc->chip.ops = &bcm2835_pwm_ops;
pc->chip.npwm = 2;
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