UbiquitousOS
/
OpenCloudOS-Kernel
mirror of https://gitee.com/OpenCloudOS/OpenCloudOS-Kernel.git
11
0
Fork 0
Code Issues Projects Releases Wiki Activity

pwm: atmel: Fix incorrect CDTY value after enabling 

CUPD is not flushed before enabling the channel so it will update
CDTY/CPRD just after one period. So we always set CUPD, even when the
channel is not enabled.

Signed-off-by: Alexandre Belloni <alexandre.belloni@free-electrons.com>
Acked-by: Nicolas Ferre <nicolas.ferre@atmel.com>
Signed-off-by: Thierry Reding <thierry.reding@gmail.com>
This commit is contained in:
Alexandre Belloni 2015-05-25 15:19:55 +02:00 committed by Thierry Reding
parent cccb94543c
commit 4c027f7ba8
1 changed files with 18 additions and 17 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

19
drivers/pwm/pwm-atmel.c
View File

@ -155,25 +155,26 @@ static void atmel_pwm_config_v1(struct pwm_chip *chip, struct pwm_device *pwm,
struct atmel_pwm_chip *atmel_pwm = to_atmel_pwm_chip(chip);
unsigned int val;
if (test_bit(PWMF_ENABLED, &pwm->flags)) {
/*
* If the PWM channel is enabled, using the update register,
* it needs to set bit 10 of CMR to 0
*/
atmel_pwm_ch_writel(atmel_pwm, pwm->hwpwm, PWMV1_CUPD, dty);
val = atmel_pwm_ch_readl(atmel_pwm, pwm->hwpwm, PWM_CMR);
val &= ~PWM_CMR_UPD_CDTY;
atmel_pwm_ch_writel(atmel_pwm, pwm->hwpwm, PWM_CMR, val);
} else {
/*
* If the PWM channel is disabled, write value to duty and
* period registers directly.
* If the PWM channel is enabled, only update CDTY by using the update
* register, it needs to set bit 10 of CMR to 0
*/
if (test_bit(PWMF_ENABLED, &pwm->flags))
return;
/*
* If the PWM channel is disabled, write value to duty and period
* registers directly.
*/
atmel_pwm_ch_writel(atmel_pwm, pwm->hwpwm, PWMV1_CDTY, dty);
atmel_pwm_ch_writel(atmel_pwm, pwm->hwpwm, PWMV1_CPRD, prd);
}
}
static void atmel_pwm_config_v2(struct pwm_chip *chip, struct pwm_device *pwm,
unsigned long dty, unsigned long prd)