[PATCH] gpio/at91: free GPIO after configuring as input

Alexander Stein alexanders83 at web.de
Fri Apr 11 07:24:09 PDT 2014


If the GPIO stays requested a device driver can't request it again.
e.g. Without this patch the ads7846 driver returns the following error:
ads7846 spi32766.3: failed to request/setup pendown GPIO15: -16
ads7846: probe of spi32766.3 failed with error -16

/sys/kernel/debug/gpio shows this:
GPIOs 0-31, platform/fffff200.gpio, fffff200.gpio:
[/ahb/apb/pinctrl at fffff200/gpio at fffff200] GPIOfffff200.gpio15: [gpio] set

Signed-off-by: Alexander Stein <alexanders83 at web.de>
---
I'm aware that it makes sense this GPIO is/stays requested, but either the
pinctl or device driver have to be adjusted as both can't request this GPIO.
I think the latter shouldn't change.

 drivers/pinctrl/pinctrl-at91.c | 2 ++
 1 file changed, 2 insertions(+)

diff --git a/drivers/pinctrl/pinctrl-at91.c b/drivers/pinctrl/pinctrl-at91.c
index d990e33..63176f2 100644
--- a/drivers/pinctrl/pinctrl-at91.c
+++ b/drivers/pinctrl/pinctrl-at91.c
@@ -1493,6 +1493,8 @@ static int at91_gpio_irq_domain_xlate(struct irq_domain *d,
 	if (ret)
 		return ret;
 
+	gpio_free(pin);
+
 	return 0;
 }
 
-- 
1.9.2




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