diff options
| author | Philip, Avinash <avinashphilip@ti.com> | 2012-09-06 10:40:02 +0530 |
|---|---|---|
| committer | Thierry Reding <thierry.reding@avionic-design.de> | 2012-09-10 17:05:52 +0200 |
| commit | 454870a44b0687675180506b7774fb559d610675 (patch) | |
| tree | 4ce95213a641f5911350a1a085e5fc1cee9c477b /drivers/pwm/pwm-tiecap.c | |
| parent | 6354316dbe5a13b25bea15d7ffc891be025eb267 (diff) | |
| download | linux-454870a44b0687675180506b7774fb559d610675.tar.bz2 | |
pwm: pwm-tiecap: Add support for configuring polarity of PWM
ECAP APWM hardware supports polarity configuration of PWM output.
This commit adds support for polarity configuration of ECAP APWM.
Signed-off-by: Philip, Avinash <avinashphilip@ti.com>
Signed-off-by: Thierry Reding <thierry.reding@avionic-design.de>
Diffstat (limited to 'drivers/pwm/pwm-tiecap.c')
| -rw-r--r-- | drivers/pwm/pwm-tiecap.c | 22 |
1 files changed, 22 insertions, 0 deletions
diff --git a/drivers/pwm/pwm-tiecap.c b/drivers/pwm/pwm-tiecap.c index 4b6688909fee..081471fbb097 100644 --- a/drivers/pwm/pwm-tiecap.c +++ b/drivers/pwm/pwm-tiecap.c @@ -32,6 +32,7 @@ #define CAP3 0x10 #define CAP4 0x14 #define ECCTL2 0x2A +#define ECCTL2_APWM_POL_LOW BIT(10) #define ECCTL2_APWM_MODE BIT(9) #define ECCTL2_SYNC_SEL_DISA (BIT(7) | BIT(6)) #define ECCTL2_TSCTR_FREERUN BIT(4) @@ -111,6 +112,26 @@ static int ecap_pwm_config(struct pwm_chip *chip, struct pwm_device *pwm, return 0; } +static int ecap_pwm_set_polarity(struct pwm_chip *chip, struct pwm_device *pwm, + enum pwm_polarity polarity) +{ + struct ecap_pwm_chip *pc = to_ecap_pwm_chip(chip); + unsigned short reg_val; + + pm_runtime_get_sync(pc->chip.dev); + reg_val = readw(pc->mmio_base + ECCTL2); + if (polarity == PWM_POLARITY_INVERSED) + /* Duty cycle defines LOW period of PWM */ + reg_val |= ECCTL2_APWM_POL_LOW; + else + /* Duty cycle defines HIGH period of PWM */ + reg_val &= ~ECCTL2_APWM_POL_LOW; + + writew(reg_val, pc->mmio_base + ECCTL2); + pm_runtime_put_sync(pc->chip.dev); + return 0; +} + static int ecap_pwm_enable(struct pwm_chip *chip, struct pwm_device *pwm) { struct ecap_pwm_chip *pc = to_ecap_pwm_chip(chip); @@ -157,6 +178,7 @@ static void ecap_pwm_free(struct pwm_chip *chip, struct pwm_device *pwm) static const struct pwm_ops ecap_pwm_ops = { .free = ecap_pwm_free, .config = ecap_pwm_config, + .set_polarity = ecap_pwm_set_polarity, .enable = ecap_pwm_enable, .disable = ecap_pwm_disable, .owner = THIS_MODULE, |