From: Bartosz Golaszewski <bartosz.golaszewski@xxxxxxxxxx>
As per the API contract - gpio_chip::get_direction() may fail and return
a negative error number. However, we treat it as if it always returned 0
or 1. Check the return value of the callback and propagate the error
number up the stack.
Cc: stable@xxxxxxxxxxxxxxx
Signed-off-by: Bartosz Golaszewski <bartosz.golaszewski@xxxxxxxxxx>
---
drivers/gpio/gpiolib.c | 44 +++++++++++++++++++++++++++++---------------
1 file changed, 29 insertions(+), 15 deletions(-)
diff --git a/drivers/gpio/gpiolib.c b/drivers/gpio/gpiolib.c
index 679ed764cb14..5d3774dc748b 100644
--- a/drivers/gpio/gpiolib.c
+++ b/drivers/gpio/gpiolib.c
@@ -1057,8 +1057,11 @@ int gpiochip_add_data_with_key(struct gpio_chip *gc, void *data,
desc->gdev = gdev;
if (gc->get_direction && gpiochip_line_is_valid(gc, desc_index)) {
- assign_bit(FLAG_IS_OUT,
- &desc->flags, !gc->get_direction(gc, desc_index));
+ ret = gc->get_direction(gc, desc_index);
+ if (ret < 0)
+ goto err_cleanup_desc_srcu;
+
+ assign_bit(FLAG_IS_OUT, &desc->flags, !ret);
} else {
assign_bit(FLAG_IS_OUT,
&desc->flags, !gc->direction_input);
@@ -2728,13 +2731,18 @@ int gpiod_direction_input_nonotify(struct gpio_desc *desc)
if (guard.gc->direction_input) {
ret = guard.gc->direction_input(guard.gc,
gpio_chip_hwgpio(desc));
- } else if (guard.gc->get_direction &&
- (guard.gc->get_direction(guard.gc,
- gpio_chip_hwgpio(desc)) != 1)) {
- gpiod_warn(desc,
- "%s: missing direction_input() operation and line is output\n",
- __func__);
- return -EIO;
+ } else if (guard.gc->get_direction) {
+ ret = guard.gc->get_direction(guard.gc,
+ gpio_chip_hwgpio(desc));
+ if (ret < 0)
+ return ret;
+
+ if (ret != GPIO_LINE_DIRECTION_IN) {
+ gpiod_warn(desc,
+ "%s: missing direction_input() operation and line is output\n",
+ __func__);
+ return -EIO;
+ }
}
if (ret == 0) {
clear_bit(FLAG_IS_OUT, &desc->flags);
@@ -2771,12 +2779,18 @@ static int gpiod_direction_output_raw_commit(struct gpio_desc *desc, int value)
gpio_chip_hwgpio(desc), val);
} else {
/* Check that we are in output mode if we can */
- if (guard.gc->get_direction &&
- guard.gc->get_direction(guard.gc, gpio_chip_hwgpio(desc))) {
- gpiod_warn(desc,
- "%s: missing direction_output() operation\n",
- __func__);
- return -EIO;
+ if (guard.gc->get_direction) {
+ ret = guard.gc->get_direction(guard.gc,
+ gpio_chip_hwgpio(desc));
+ if (ret < 0)
+ return ret;
+
+ if (ret != GPIO_LINE_DIRECTION_OUT) {
+ gpiod_warn(desc,
+ "%s: missing direction_output() operation\n",
+ __func__);
+ return -EIO;
+ }
}
/*
* If we can't actively set the direction, we are some
--
2.45.2
