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pwm: lpc32xx: Set PWM_PIN_LEVEL bit to default value 

The PWM_PIN_LEVEL bit is leave unset by the kernel PWM driver.

Prior to commit 08ee77b5a5,
the PWM_PIN_LEVEL bit was always clear when the PWM was disable
and a 0 logic level was apply to the output.

According to the LPC32x0 User Manual [1],
the default value for bit 30 (PWM_PIN_LEVEL) is 0.

This change initialize the pin level to 0 (default value) and
update the register value accordingly.

[1] http://www.nxp.com/documents/user_manual/UM10326.pdf

Signed-off-by: Sylvain Lemieux <slemieux@tycoint.com>
Signed-off-by: Thierry Reding <thierry.reding@gmail.com>
This commit is contained in:
Sylvain Lemieux 2016-06-27 09:09:55 -04:00 committed by Thierry Reding
parent ef1f09eca7
commit acfd92fdfb
1 changed files with 7 additions and 0 deletions
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7
drivers/pwm/pwm-lpc32xx.c
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@ -25,6 +25,7 @@ struct lpc32xx_pwm_chip {
};
#define PWM_ENABLE BIT(31)
#define PWM_PIN_LEVEL BIT(30)
#define to_lpc32xx_pwm_chip(_chip) \
container_of(_chip, struct lpc32xx_pwm_chip, chip)
@ -103,6 +104,7 @@ static int lpc32xx_pwm_probe(struct platform_device *pdev)
struct lpc32xx_pwm_chip *lpc32xx;
struct resource *res;
int ret;
u32 val;
lpc32xx = devm_kzalloc(&pdev->dev, sizeof(*lpc32xx), GFP_KERNEL);
if (!lpc32xx)
@ -128,6 +130,11 @@ static int lpc32xx_pwm_probe(struct platform_device *pdev)
return ret;
}
/* When PWM is disable, configure the output to the default value */
val = readl(lpc32xx->base + (lpc32xx->chip.pwms[0].hwpwm << 2));
val &= ~PWM_PIN_LEVEL;
writel(val, lpc32xx->base + (lpc32xx->chip.pwms[0].hwpwm << 2));
platform_set_drvdata(pdev, lpc32xx);
return 0;