[PATCH 3.19 150/175] gpiolib: of: allow of_gpiochip_find_and_xlate to find more than one chip per node

Greg Kroah-Hartman
2015-03-04T06:21:59Z

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

commit 9cf75e9e4ddd587ac12e88e8751c358b7b27e95f upstream.

The change:

7b8792bbdffdff3abda704f89c6a45ea97afdc62
gpiolib: of: Correct error handling in of_get_named_gpiod_flags

assumed that only one gpio-chip is registred per of-node.
Some drivers register more than one chip per of-node, so
adjust the matching function of_gpiochip_find_and_xlate to
not stop looking for chips if a node-match is found and
the translation fails.

Fixes: 7b8792bbdffd ("gpiolib: of: Correct error handling in of_get_named_gpiod_flags")
Signed-off-by: Hans Holmberg <hans.holmberg@intel.com>
Acked-by: Alexandre Courbot <acourbot@nvidia.com>
Tested-by: Robert Jarzmik <robert.jarzmik@free.fr>
Tested-by: Tyler Hall <tylerwhall@gmail.com>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

---
drivers/gpio/gpiolib-of.c | 9 +++++----
1 file changed, 5 insertions(+), 4 deletions(-)

--- a/drivers/gpio/gpiolib-of.c
+++ b/drivers/gpio/gpiolib-of.c
@@ -46,12 +46,13 @@ static int of_gpiochip_find_and_xlate(st

ret = gc->of_xlate(gc, &gg_data->gpiospec, gg_data->flags);
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
+ /* We've found a gpio chip, but the translation failed.
+ * Store translation error in out_gpio.
+ * Return false to keep looking, as more than one gpio chip
+ * could be registered per of-node.
*/
gg_data->out_gpio = ERR_PTR(ret);
- return true;
+ return false;
}

gg_data->out_gpio = gpiochip_get_desc(gc, ret);