From: Jonas Schwöbel <[email protected]> Add active-low support to the PWM controller, useful for active-low pwm-leds.
Signed-off-by: Jonas Schwöbel <[email protected]> Signed-off-by: Svyatoslav Ryhel <[email protected]> --- drivers/pwm/tegra_pwm.c | 17 +++++++++++++++++ 1 file changed, 17 insertions(+) diff --git a/drivers/pwm/tegra_pwm.c b/drivers/pwm/tegra_pwm.c index 7105d6db90d..3d398490408 100644 --- a/drivers/pwm/tegra_pwm.c +++ b/drivers/pwm/tegra_pwm.c @@ -12,8 +12,21 @@ struct tegra_pwm_priv { struct pwm_ctlr *regs; + u8 polarity; }; +static int tegra_pwm_set_invert(struct udevice *dev, uint channel, bool polarity) +{ + struct tegra_pwm_priv *priv = dev_get_priv(dev); + + if (channel >= 4) + return -EINVAL; + + clrsetbits_8(&priv->polarity, BIT(channel), (polarity << channel)); + + return 0; +} + static int tegra_pwm_set_config(struct udevice *dev, uint channel, uint period_ns, uint duty_ns) { @@ -28,6 +41,9 @@ static int tegra_pwm_set_config(struct udevice *dev, uint channel, pulse_width = duty_ns * 255 / period_ns; + if (priv->polarity & BIT(channel)) + pulse_width = 256 - pulse_width; + reg = pulse_width << PWM_WIDTH_SHIFT; reg |= 1 << PWM_DIVIDER_SHIFT; reg |= PWM_ENABLE_MASK; @@ -72,6 +88,7 @@ static int tegra_pwm_probe(struct udevice *dev) static const struct pwm_ops tegra_pwm_ops = { .set_config = tegra_pwm_set_config, .set_enable = tegra_pwm_set_enable, + .set_invert = tegra_pwm_set_invert, }; static const struct udevice_id tegra_pwm_ids[] = { -- 2.51.0
