[PATCH 3.10 25/50] gpiolib: of: Correct error handling in of_get_named_gpiod_flags

Greg Kroah-Hartman
2015-01-25T18:09:00Z

From: Hans Holmberg <hans.holmberg@intel.com>

commit 7b8792bbdffdff3abda704f89c6a45ea97afdc62 upstream.

of_get_named_gpiod_flags fails with -EPROBE_DEFER in cases
where the gpio chip is available and the GPIO translation fails.

This causes drivers to be re-probed erroneusly, and hides the
real problem(i.e. the GPIO number being out of range).

Signed-off-by: Hans Holmberg <hans.holmberg@intel.com>
Reviewed-by: Alexandre Courbot <acourbot@nvidia.com>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

---
drivers/gpio/gpiolib-of.c | 10 ++++++++--
1 file changed, 8 insertions(+), 2 deletions(-)

--- a/drivers/gpio/gpiolib-of.c
+++ b/drivers/gpio/gpiolib-of.c
@@ -42,8 +42,14 @@ static int of_gpiochip_find_and_xlate(st
return false;

ret = gc->of_xlate(gc, &gg_data->gpiospec, gg_data->flags);
- if (ret < 0)
- return false;
+ if (ret < 0) {
+ /* We've found the gpio chip, but the translation failed.
+ * Return true to stop looking and return the translation
+ * error via out_gpio
+ */
+ gg_data->out_gpio = ERR_PTR(ret);
+ return true;
+ }

gg_data->out_gpio = ret + gc->base;
return true;