Re: [RCF PATCH,v2,2/2] pwm: imx: Configure output to GPIO in disabled state
From: Uwe Kleine-König <hidden>
Date: 2018-11-07 09:34:08
Also in:
linux-pwm, lkml
Subsystem:
pwm subsystem, the rest · Maintainers:
Uwe Kleine-König, Linus Torvalds
Hello Michal, just to state it more explicitly, I think the following patch (not even compile tested) is much preferable over your approach:
diff --git a/drivers/pwm/pwm-imx.c b/drivers/pwm/pwm-imx.c
index 1d5242c9cde0..af88644b5efb 100644
--- a/drivers/pwm/pwm-imx.c
+++ b/drivers/pwm/pwm-imx.c@@ -216,7 +216,14 @@ static int imx_pwm_apply_v2(struct pwm_chip *chip, struct pwm_device *pwm, cr |= MX3_PWMCR_POUTC; writel(cr, imx->mmio_base + MX3_PWMCR); - } else if (cstate.enabled) { + } else if (cstate.enabled && state->polarity == PWM_POLARITY_NORMAL) { + /* + * When disabled in hardware the output pin goes to 0 + * independant of the polarity setting. The expectation of some + * people however is that after disabling the pin goes to the + * inactive level which isn't given for an inversed pwm, so + * only disable for normal polarity. + */ writel(0, imx->mmio_base + MX3_PWMCR); clk_disable_unprepare(imx->clk_per);
I think it solves most if not all problems you want to address with the pinctrl stuff. Best regards Uwe -- Pengutronix e.K. | Uwe Kleine-König | Industrial Linux Solutions | http://www.pengutronix.de/ |