Commit 454870a4 authored by Philip, Avinash's avatar Philip, Avinash Committed by Thierry Reding
Browse files

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: default avatarPhilip, Avinash <avinashphilip@ti.com>
Signed-off-by: default avatarThierry Reding <thierry.reding@avionic-design.de>
parent 6354316d

drivers/pwm/pwm-tiecap.c

+22 −0
Original line number Diff line number Diff line
@@ -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,