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authorSylvain Lemieux <slemieux@tycoint.com>2016-06-27 09:09:55 -0400
committerThierry Reding <thierry.reding@gmail.com>2016-07-11 12:49:29 +0200
commitacfd92fdfb9384d54d9404101e8657e75c2372f3 (patch)
treeda50555ec0c69fb074c7f8965b23d4b4bbf7a08f /drivers/pwm
parentef1f09eca74a42d39ce81adec444743a6ff018aa (diff)
downloadlinux-acfd92fdfb9384d54d9404101e8657e75c2372f3.tar.bz2
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 08ee77b5a5de27ad63c92262ebcb4efe0da93b58, 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>
Diffstat (limited to 'drivers/pwm')
-rw-r--r--drivers/pwm/pwm-lpc32xx.c7
1 files changed, 7 insertions, 0 deletions
diff --git a/drivers/pwm/pwm-lpc32xx.c b/drivers/pwm/pwm-lpc32xx.c
index 4d470c1a406a..a9b3cff96aac 100644
--- a/drivers/pwm/pwm-lpc32xx.c
+++ b/drivers/pwm/pwm-lpc32xx.c
@@ -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;