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authorJ. Bruce Fields <bfields@redhat.com>2014-11-19 12:06:30 -0500
committerJ. Bruce Fields <bfields@redhat.com>2014-11-19 12:06:30 -0500
commit56429e9b3be567a173bd05f5594faf8522c34d3a (patch)
treed218d430ed992cdfa42da084bf36e5aa3c2ecb26 /drivers/pwm/pwm-atmel.c
parent5b095e99928cc13332d364f7cca7a9ca684369b4 (diff)
parent093a1468b6edb0e568be7311b8d2228d205702db (diff)
merge nfs bugfixes into nfsd for-3.19 branch
In addition to nfsd bugfixes, there are some fixes in -rc5 for client bugs that can interfere with my testing.
Diffstat (limited to 'drivers/pwm/pwm-atmel.c')
-rw-r--r--drivers/pwm/pwm-atmel.c24
1 files changed, 11 insertions, 13 deletions
diff --git a/drivers/pwm/pwm-atmel.c b/drivers/pwm/pwm-atmel.c
index 6e700a541ca3..d3c22de9ee47 100644
--- a/drivers/pwm/pwm-atmel.c
+++ b/drivers/pwm/pwm-atmel.c
@@ -102,7 +102,7 @@ static int atmel_pwm_config(struct pwm_chip *chip, struct pwm_device *pwm,
int duty_ns, int period_ns)
{
struct atmel_pwm_chip *atmel_pwm = to_atmel_pwm_chip(chip);
- unsigned long clk_rate, prd, dty;
+ unsigned long prd, dty;
unsigned long long div;
unsigned int pres = 0;
u32 val;
@@ -113,20 +113,18 @@ static int atmel_pwm_config(struct pwm_chip *chip, struct pwm_device *pwm,
return -EBUSY;
}
- clk_rate = clk_get_rate(atmel_pwm->clk);
- div = clk_rate;
+ /* Calculate the period cycles and prescale value */
+ div = (unsigned long long)clk_get_rate(atmel_pwm->clk) * period_ns;
+ do_div(div, NSEC_PER_SEC);
- /* Calculate the period cycles */
while (div > PWM_MAX_PRD) {
- div = clk_rate / (1 << pres);
- div = div * period_ns;
- /* 1/Hz = 100000000 ns */
- do_div(div, 1000000000);
-
- if (pres++ > PRD_MAX_PRES) {
- dev_err(chip->dev, "pres exceeds the maximum value\n");
- return -EINVAL;
- }
+ div >>= 1;
+ pres++;
+ }
+
+ if (pres > PRD_MAX_PRES) {
+ dev_err(chip->dev, "pres exceeds the maximum value\n");
+ return -EINVAL;
}
/* Calculate the duty cycles */