[PATCH v9 5/9] gpio: Remove gpio_chip_guard by using revocable

Tzung-Bi Shih
2026-04-27T13:59:48Z

Struct gpio_device now provides a revocable provider to the underlying
struct gpio_chip. Leverage revocable for accessing the struct
gpio_chip instead of using gpio_chip_guard.

Signed-off-by: Tzung-Bi Shih <tzungbi@kernel.org>
---
v9:
- New to the series.
- Rename "chip_rp" -> "chip_rev".

v4 - v8:
- Doesn't exist.

v3: https://lore.kernel.org/all/20260213092958.864411-10-tzungbi@kernel.org
- Change revocable API usages accordingly.

v2: https://lore.kernel.org/all/20260203061059.975605-10-tzungbi@kernel.org
- Separate from v1 for including gpio_chip_guard only.

v1: https://lore.kernel.org/all/20260116081036.352286-23-tzungbi@kernel.org

---
drivers/gpio/gpiolib-cdev.c | 9 +-
drivers/gpio/gpiolib-sysfs.c | 31 +++----
drivers/gpio/gpiolib.c | 164 ++++++++++++++++-------------------
drivers/gpio/gpiolib.h | 21 -----
4 files changed, 91 insertions(+), 134 deletions(-)

diff --git a/drivers/gpio/gpiolib-cdev.c b/drivers/gpio/gpiolib-cdev.c
index d8a7ccb406a5..4837497c5e6e 100644
--- a/drivers/gpio/gpiolib-cdev.c
+++ b/drivers/gpio/gpiolib-cdev.c
@@ -2156,10 +2156,9 @@ static void gpio_desc_to_lineinfo(struct gpio_desc *desc,
u32 debounce_period_us;
unsigned long dflags;
const char *label;
+ struct gpio_chip *gc;

- CLASS(gpio_chip_guard, guard)(desc);
- if (!guard.gc)
- return;
+ revocable_try_access_or_return_void(&desc->gdev->chip_rev, gc);

memset(info, 0, sizeof(*info));
info->offset = gpiod_hwgpio(desc);
@@ -2192,10 +2191,10 @@ static void gpio_desc_to_lineinfo(struct gpio_desc *desc,
test_bit(GPIOD_FLAG_IS_HOGGED, &dflags) ||
test_bit(GPIOD_FLAG_EXPORT, &dflags) ||
test_bit(GPIOD_FLAG_SYSFS, &dflags) ||
- !gpiochip_line_is_valid(guard.gc, info->offset)) {
+ !gpiochip_line_is_valid(gc, info->offset)) {
info->flags |= GPIO_V2_LINE_FLAG_USED;
} else if (!atomic) {
- if (!pinctrl_gpio_can_use_line(guard.gc, info->offset))
+ if (!pinctrl_gpio_can_use_line(gc, info->offset))
info->flags |= GPIO_V2_LINE_FLAG_USED;
}

diff --git a/drivers/gpio/gpiolib-sysfs.c b/drivers/gpio/gpiolib-sysfs.c
index fc06b0c2881b..c40320433ff7 100644
--- a/drivers/gpio/gpiolib-sysfs.c
+++ b/drivers/gpio/gpiolib-sysfs.c
@@ -10,6 +10,7 @@
#include <linux/list.h>
#include <linux/mutex.h>
#include <linux/printk.h>
+#include <linux/revocable.h>
#include <linux/slab.h>
#include <linux/string.h>
#include <linux/srcu.h>
@@ -215,10 +216,9 @@ static int gpio_sysfs_request_irq(struct gpiod_data *data, unsigned char flags)
struct gpio_desc *desc = data->desc;
unsigned long irq_flags;
int ret;
+ struct gpio_chip *gc;

- CLASS(gpio_chip_guard, guard)(desc);
- if (!guard.gc)
- return -ENODEV;
+ revocable_try_access_or_return(&desc->gdev->chip_rev, gc);

data->irq = gpiod_to_irq(desc);
if (data->irq < 0)
@@ -244,7 +244,7 @@ static int gpio_sysfs_request_irq(struct gpiod_data *data, unsigned char flags)
* Remove this redundant call (along with the corresponding unlock)
* when those drivers have been fixed.
*/
- ret = gpiochip_lock_as_irq(guard.gc, gpiod_hwgpio(desc));
+ ret = gpiochip_lock_as_irq(gc, gpiod_hwgpio(desc));
if (ret < 0)
goto err_clr_bits;

@@ -258,7 +258,7 @@ static int gpio_sysfs_request_irq(struct gpiod_data *data, unsigned char flags)
return 0;

err_unlock:
- gpiochip_unlock_as_irq(guard.gc, gpiod_hwgpio(desc));
+ gpiochip_unlock_as_irq(gc, gpiod_hwgpio(desc));
err_clr_bits:
clear_bit(GPIOD_FLAG_EDGE_RISING, &desc->flags);
clear_bit(GPIOD_FLAG_EDGE_FALLING, &desc->flags);
@@ -273,14 +273,13 @@ static int gpio_sysfs_request_irq(struct gpiod_data *data, unsigned char flags)
static void gpio_sysfs_free_irq(struct gpiod_data *data)
{
struct gpio_desc *desc = data->desc;
+ struct gpio_chip *gc;

- CLASS(gpio_chip_guard, guard)(desc);
- if (!guard.gc)
- return;
+ revocable_try_access_or_return_void(&desc->gdev->chip_rev, gc);

data->irq_flags = 0;
free_irq(data->irq, data);
- gpiochip_unlock_as_irq(guard.gc, gpiod_hwgpio(desc));
+ gpiochip_unlock_as_irq(gc, gpiod_hwgpio(desc));
clear_bit(GPIOD_FLAG_EDGE_RISING, &desc->flags);
clear_bit(GPIOD_FLAG_EDGE_FALLING, &desc->flags);
}
@@ -473,13 +472,12 @@ static DEVICE_ATTR_RO(ngpio);
static int export_gpio_desc(struct gpio_desc *desc)
{
int offset, ret;
+ struct gpio_chip *gc;

- CLASS(gpio_chip_guard, guard)(desc);
- if (!guard.gc)
- return -ENODEV;
+ revocable_try_access_or_return(&desc->gdev->chip_rev, gc);

offset = gpiod_hwgpio(desc);
- if (!gpiochip_line_is_valid(guard.gc, offset)) {
+ if (!gpiochip_line_is_valid(gc, offset)) {
pr_debug_ratelimited("%s: GPIO %d masked\n", __func__,
gpiod_hwgpio(desc));
return -EINVAL;
@@ -732,6 +730,7 @@ int gpiod_export(struct gpio_desc *desc, bool direction_may_change)
struct gpio_device *gdev;
struct attribute **attrs;
int status;
+ struct gpio_chip *gc;

/* can't export until sysfs is available ... */
if (!class_is_registered(&gpio_class)) {
@@ -744,9 +743,7 @@ int gpiod_export(struct gpio_desc *desc, bool direction_may_change)
return -EINVAL;
}

- CLASS(gpio_chip_guard, guard)(desc);
- if (!guard.gc)
- return -ENODEV;
+ revocable_try_access_or_return(&desc->gdev->chip_rev, gc);

if (test_and_set_bit(GPIOD_FLAG_EXPORT, &desc->flags))
return -EPERM;
@@ -769,7 +766,7 @@ int gpiod_export(struct gpio_desc *desc, bool direction_may_change)

desc_data->desc = desc;
mutex_init(&desc_data->mutex);
- if (guard.gc->direction_input && guard.gc->direction_output)
+ if (gc->direction_input && gc->direction_output)
desc_data->direction_can_change = direction_may_change;
else
desc_data->direction_can_change = false;
diff --git a/drivers/gpio/gpiolib.c b/drivers/gpio/gpiolib.c
index 20448d5aab93..2cac1e15e1e5 100644
--- a/drivers/gpio/gpiolib.c
+++ b/drivers/gpio/gpiolib.c
@@ -454,14 +454,13 @@ int gpiod_get_direction(struct gpio_desc *desc)
unsigned long flags;
unsigned int offset;
int ret;
+ struct gpio_chip *gc;

ret = validate_desc(desc, __func__);
if (ret <= 0)
return -EINVAL;

- CLASS(gpio_chip_guard, guard)(desc);
- if (!guard.gc)
- return -ENODEV;
+ revocable_try_access_or_return(&desc->gdev->chip_rev, gc);

offset = gpiod_hwgpio(desc);
flags = READ_ONCE(desc->flags);
@@ -474,7 +473,7 @@ int gpiod_get_direction(struct gpio_desc *desc)
test_bit(GPIOD_FLAG_IS_OUT, &flags))
return 0;

- ret = gpiochip_get_direction(guard.gc, offset);
+ ret = gpiochip_get_direction(gc, offset);
if (ret < 0)
return ret;

@@ -2561,16 +2560,15 @@ int gpiod_request_commit(struct gpio_desc *desc, const char *label)
{
unsigned int offset;
int ret;
+ struct gpio_chip *gc;

- CLASS(gpio_chip_guard, guard)(desc);
- if (!guard.gc)
- return -ENODEV;
+ revocable_try_access_or_return(&desc->gdev->chip_rev, gc);

if (test_and_set_bit(GPIOD_FLAG_REQUESTED, &desc->flags))
return -EBUSY;

offset = gpiod_hwgpio(desc);
- if (!gpiochip_line_is_valid(guard.gc, offset)) {
+ if (!gpiochip_line_is_valid(gc, offset)) {
ret = -EINVAL;
goto out_clear_bit;
}
@@ -2579,15 +2577,15 @@ int gpiod_request_commit(struct gpio_desc *desc, const char *label)
* before IRQs are enabled, for non-sleeping (SOC) GPIOs.
*/

- if (guard.gc->request) {
- ret = guard.gc->request(guard.gc, offset);
+ if (gc->request) {
+ ret = gc->request(gc, offset);
if (ret > 0)
ret = -EBADE;
if (ret)
goto out_clear_bit;
}

- if (guard.gc->get_direction)
+ if (gc->get_direction)
gpiod_get_direction(desc);

ret = desc_set_label(desc, label ? : "?");
@@ -2624,16 +2622,17 @@ int gpiod_request(struct gpio_desc *desc, const char *label)
void gpiod_free_commit(struct gpio_desc *desc)
{
unsigned long flags;
+ struct gpio_chip *gc;

might_sleep();

- CLASS(gpio_chip_guard, guard)(desc);
+ revocable_try_access_or_return_void(&desc->gdev->chip_rev, gc);

flags = READ_ONCE(desc->flags);

- if (guard.gc && test_bit(GPIOD_FLAG_REQUESTED, &flags)) {
- if (guard.gc->free)
- guard.gc->free(guard.gc, gpiod_hwgpio(desc));
+ if (test_bit(GPIOD_FLAG_REQUESTED, &flags)) {
+ if (gc->free)
+ gc->free(gc, gpiod_hwgpio(desc));

clear_bit(GPIOD_FLAG_ACTIVE_LOW, &flags);
clear_bit(GPIOD_FLAG_REQUESTED, &flags);
@@ -2785,15 +2784,14 @@ EXPORT_SYMBOL_GPL(gpiochip_free_own_desc);
int gpio_do_set_config(struct gpio_desc *desc, unsigned long config)
{
int ret;
+ struct gpio_chip *gc;

- CLASS(gpio_chip_guard, guard)(desc);
- if (!guard.gc)
- return -ENODEV;
+ revocable_try_access_or_return(&desc->gdev->chip_rev, gc);

- if (!guard.gc->set_config)
+ if (!gc->set_config)
return -ENOTSUPP;

- ret = guard.gc->set_config(guard.gc, gpiod_hwgpio(desc), config);
+ ret = gc->set_config(gc, gpiod_hwgpio(desc), config);
if (ret > 0)
ret = -EBADE;

@@ -2962,17 +2960,16 @@ EXPORT_SYMBOL_GPL(gpiod_direction_input);
int gpiod_direction_input_nonotify(struct gpio_desc *desc)
{
int ret = 0, dir;
+ struct gpio_chip *gc;

- CLASS(gpio_chip_guard, guard)(desc);
- if (!guard.gc)
- return -ENODEV;
+ revocable_try_access_or_return(&desc->gdev->chip_rev, gc);

/*
* It is legal to have no .get() and .direction_input() specified if
* the chip is output-only, but you can't specify .direction_input()
* and not support the .get() operation, that doesn't make sense.
*/
- if (!guard.gc->get && guard.gc->direction_input) {
+ if (!gc->get && gc->direction_input) {
gpiod_warn(desc,
"%s: missing get() but have direction_input()\n",
__func__);
@@ -2985,11 +2982,10 @@ int gpiod_direction_input_nonotify(struct gpio_desc *desc)
* direction (if .get_direction() is supported) else we silently
* assume we are in input mode after this.
*/
- if (guard.gc->direction_input) {
- ret = gpiochip_direction_input(guard.gc,
- gpiod_hwgpio(desc));
- } else if (guard.gc->get_direction) {
- dir = gpiochip_get_direction(guard.gc, gpiod_hwgpio(desc));
+ if (gc->direction_input) {
+ ret = gpiochip_direction_input(gc, gpiod_hwgpio(desc));
+ } else if (gc->get_direction) {
+ dir = gpiochip_get_direction(gc, gpiod_hwgpio(desc));
if (dir < 0)
return dir;

@@ -3029,31 +3025,28 @@ static int gpiochip_set(struct gpio_chip *gc, unsigned int offset, int value)
static int gpiod_direction_output_raw_commit(struct gpio_desc *desc, int value)
{
int val = !!value, ret = 0, dir;
+ struct gpio_chip *gc;

- CLASS(gpio_chip_guard, guard)(desc);
- if (!guard.gc)
- return -ENODEV;
+ revocable_try_access_or_return(&desc->gdev->chip_rev, gc);

/*
* It's OK not to specify .direction_output() if the gpiochip is
* output-only, but if there is then not even a .set() operation it
* is pretty tricky to drive the output line.
*/
- if (!guard.gc->set && !guard.gc->direction_output) {
+ if (!gc->set && !gc->direction_output) {
gpiod_warn(desc,
"%s: missing set() and direction_output() operations\n",
__func__);
return -EIO;
}

- if (guard.gc->direction_output) {
- ret = gpiochip_direction_output(guard.gc,
- gpiod_hwgpio(desc), val);
+ if (gc->direction_output) {
+ ret = gpiochip_direction_output(gc, gpiod_hwgpio(desc), val);
} else {
/* Check that we are in output mode if we can */
- if (guard.gc->get_direction) {
- dir = gpiochip_get_direction(guard.gc,
- gpiod_hwgpio(desc));
+ if (gc->get_direction) {
+ dir = gpiochip_get_direction(gc, gpiod_hwgpio(desc));
if (dir < 0)
return dir;

@@ -3068,7 +3061,7 @@ static int gpiod_direction_output_raw_commit(struct gpio_desc *desc, int value)
* If we can't actively set the direction, we are some
* output-only chip, so just drive the output as desired.
*/
- ret = gpiochip_set(guard.gc, gpiod_hwgpio(desc), val);
+ ret = gpiochip_set(gc, gpiod_hwgpio(desc), val);
if (ret)
return ret;
}
@@ -3206,20 +3199,18 @@ int gpiod_direction_output_nonotify(struct gpio_desc *desc, int value)
int gpiod_enable_hw_timestamp_ns(struct gpio_desc *desc, unsigned long flags)
{
int ret;
+ struct gpio_chip *gc;

VALIDATE_DESC(desc);

- CLASS(gpio_chip_guard, guard)(desc);
- if (!guard.gc)
- return -ENODEV;
+ revocable_try_access_or_return(&desc->gdev->chip_rev, gc);

- if (!guard.gc->en_hw_timestamp) {
+ if (!gc->en_hw_timestamp) {
gpiod_warn(desc, "%s: hw ts not supported\n", __func__);
return -ENOTSUPP;
}

- ret = guard.gc->en_hw_timestamp(guard.gc,
- gpiod_hwgpio(desc), flags);
+ ret = gc->en_hw_timestamp(gc, gpiod_hwgpio(desc), flags);
if (ret)
gpiod_warn(desc, "%s: hw ts request failed\n", __func__);

@@ -3239,20 +3230,18 @@ EXPORT_SYMBOL_GPL(gpiod_enable_hw_timestamp_ns);
int gpiod_disable_hw_timestamp_ns(struct gpio_desc *desc, unsigned long flags)
{
int ret;
+ struct gpio_chip *gc;

VALIDATE_DESC(desc);

- CLASS(gpio_chip_guard, guard)(desc);
- if (!guard.gc)
- return -ENODEV;
+ revocable_try_access_or_return(&desc->gdev->chip_rev, gc);

- if (!guard.gc->dis_hw_timestamp) {
+ if (!gc->dis_hw_timestamp) {
gpiod_warn(desc, "%s: hw ts not supported\n", __func__);
return -ENOTSUPP;
}

- ret = guard.gc->dis_hw_timestamp(guard.gc, gpiod_hwgpio(desc),
- flags);
+ ret = gc->dis_hw_timestamp(gc, gpiod_hwgpio(desc), flags);
if (ret)
gpiod_warn(desc, "%s: hw ts release failed\n", __func__);

@@ -3516,31 +3505,29 @@ int gpiod_get_array_value_complex(bool raw, bool can_sleep,
unsigned long *mask, *bits;
int first, j;

- CLASS(gpio_chip_guard, guard)(desc_array[i]);
- if (!guard.gc)
- return -ENODEV;
+ revocable_try_access_or_return(&desc_array[i]->gdev->chip_rev, gc);

- if (likely(guard.gc->ngpio <= FASTPATH_NGPIO)) {
+ if (likely(gc->ngpio <= FASTPATH_NGPIO)) {
mask = fastpath_mask;
bits = fastpath_bits;
} else {
gfp_t flags = can_sleep ? GFP_KERNEL : GFP_ATOMIC;

- mask = bitmap_alloc(guard.gc->ngpio, flags);
+ mask = bitmap_alloc(gc->ngpio, flags);
if (!mask)
return -ENOMEM;

- bits = bitmap_alloc(guard.gc->ngpio, flags);
+ bits = bitmap_alloc(gc->ngpio, flags);
if (!bits) {
bitmap_free(mask);
return -ENOMEM;
}
}

- bitmap_zero(mask, guard.gc->ngpio);
+ bitmap_zero(mask, gc->ngpio);

if (!can_sleep)
- WARN_ON(guard.gc->can_sleep);
+ WARN_ON(gc->can_sleep);

/* collect all inputs belonging to the same chip */
first = i;
@@ -3555,9 +3542,9 @@ int gpiod_get_array_value_complex(bool raw, bool can_sleep,
i = find_next_zero_bit(array_info->get_mask,
array_size, i);
} while ((i < array_size) &&
- gpio_device_chip_cmp(desc_array[i]->gdev, guard.gc));
+ gpio_device_chip_cmp(desc_array[i]->gdev, gc));

- ret = gpio_chip_get_multiple(guard.gc, mask, bits);
+ ret = gpio_chip_get_multiple(gc, mask, bits);
if (ret) {
if (mask != fastpath_mask)
bitmap_free(mask);
@@ -3706,15 +3693,14 @@ EXPORT_SYMBOL_GPL(gpiod_get_array_value);
static int gpio_set_open_drain_value_commit(struct gpio_desc *desc, bool value)
{
int ret = 0, offset = gpiod_hwgpio(desc);
+ struct gpio_chip *gc;

- CLASS(gpio_chip_guard, guard)(desc);
- if (!guard.gc)
- return -ENODEV;
+ revocable_try_access_or_return(&desc->gdev->chip_rev, gc);

if (value) {
- ret = gpiochip_direction_input(guard.gc, offset);
+ ret = gpiochip_direction_input(gc, offset);
} else {
- ret = gpiochip_direction_output(guard.gc, offset, 0);
+ ret = gpiochip_direction_output(gc, offset, 0);
if (!ret)
set_bit(GPIOD_FLAG_IS_OUT, &desc->flags);
}
@@ -3735,17 +3721,16 @@ static int gpio_set_open_drain_value_commit(struct gpio_desc *desc, bool value)
static int gpio_set_open_source_value_commit(struct gpio_desc *desc, bool value)
{
int ret = 0, offset = gpiod_hwgpio(desc);
+ struct gpio_chip *gc;

- CLASS(gpio_chip_guard, guard)(desc);
- if (!guard.gc)
- return -ENODEV;
+ revocable_try_access_or_return(&desc->gdev->chip_rev, gc);

if (value) {
- ret = gpiochip_direction_output(guard.gc, offset, 1);
+ ret = gpiochip_direction_output(gc, offset, 1);
if (!ret)
set_bit(GPIOD_FLAG_IS_OUT, &desc->flags);
} else {
- ret = gpiochip_direction_input(guard.gc, offset);
+ ret = gpiochip_direction_input(gc, offset);
}
trace_gpio_direction(desc_to_gpio(desc), !value, ret);
if (ret < 0)
@@ -3758,15 +3743,15 @@ static int gpio_set_open_source_value_commit(struct gpio_desc *desc, bool value)

static int gpiod_set_raw_value_commit(struct gpio_desc *desc, bool value)
{
+ struct gpio_chip *gc;
+
if (unlikely(!test_bit(GPIOD_FLAG_IS_OUT, &desc->flags)))
return -EPERM;

- CLASS(gpio_chip_guard, guard)(desc);
- if (!guard.gc)
- return -ENODEV;
+ revocable_try_access_or_return(&desc->gdev->chip_rev, gc);

trace_gpio_value(desc_to_gpio(desc), 0, value);
- return gpiochip_set(guard.gc, gpiod_hwgpio(desc), value);
+ return gpiochip_set(gc, gpiod_hwgpio(desc), value);
}

/*
@@ -3861,31 +3846,30 @@ int gpiod_set_array_value_complex(bool raw, bool can_sleep,
unsigned long *mask, *bits;
int count = 0;

- CLASS(gpio_chip_guard, guard)(desc_array[i]);
- if (!guard.gc)
- return -ENODEV;
+ revocable_try_access_or_return(&desc_array[i]->gdev->chip_rev,
+ gc);

- if (likely(guard.gc->ngpio <= FASTPATH_NGPIO)) {
+ if (likely(gc->ngpio <= FASTPATH_NGPIO)) {
mask = fastpath_mask;
bits = fastpath_bits;
} else {
gfp_t flags = can_sleep ? GFP_KERNEL : GFP_ATOMIC;

- mask = bitmap_alloc(guard.gc->ngpio, flags);
+ mask = bitmap_alloc(gc->ngpio, flags);
if (!mask)
return -ENOMEM;

- bits = bitmap_alloc(guard.gc->ngpio, flags);
+ bits = bitmap_alloc(gc->ngpio, flags);
if (!bits) {
bitmap_free(mask);
return -ENOMEM;
}
}

- bitmap_zero(mask, guard.gc->ngpio);
+ bitmap_zero(mask, gc->ngpio);

if (!can_sleep)
- WARN_ON(guard.gc->can_sleep);
+ WARN_ON(gc->can_sleep);

do {
struct gpio_desc *desc = desc_array[i];
@@ -3924,10 +3908,10 @@ int gpiod_set_array_value_complex(bool raw, bool can_sleep,
i = find_next_zero_bit(array_info->set_mask,
array_size, i);
} while ((i < array_size) &&
- gpio_device_chip_cmp(desc_array[i]->gdev, guard.gc));
+ gpio_device_chip_cmp(desc_array[i]->gdev, gc));
/* push collected bits to outputs */
if (count != 0) {
- ret = gpiochip_set_multiple(guard.gc, mask, bits);
+ ret = gpiochip_set_multiple(gc, mask, bits);
if (ret)
return ret;
}
@@ -5107,18 +5091,16 @@ int gpiod_hog(struct gpio_desc *desc, const char *name,
struct gpio_desc *local_desc;
int hwnum;
int ret;
+ struct gpio_chip *gc;

- CLASS(gpio_chip_guard, guard)(desc);
- if (!guard.gc)
- return -ENODEV;
+ revocable_try_access_or_return(&desc->gdev->chip_rev, gc);

if (test_and_set_bit(GPIOD_FLAG_IS_HOGGED, &desc->flags))
return 0;

hwnum = gpiod_hwgpio(desc);

- local_desc = gpiochip_request_own_desc(guard.gc, hwnum, name,
- lflags, dflags);
+ local_desc = gpiochip_request_own_desc(gc, hwnum, name, lflags, dflags);
if (IS_ERR(local_desc)) {
clear_bit(GPIOD_FLAG_IS_HOGGED, &desc->flags);
ret = PTR_ERR(local_desc);
diff --git a/drivers/gpio/gpiolib.h b/drivers/gpio/gpiolib.h
index 4e2e98f61f5a..90ad9b7fdfdd 100644
--- a/drivers/gpio/gpiolib.h
+++ b/drivers/gpio/gpiolib.h
@@ -228,27 +228,6 @@ struct gpio_desc {

#define gpiod_not_found(desc) (IS_ERR(desc) && PTR_ERR(desc) == -ENOENT)

-struct gpio_chip_guard {
- struct gpio_device *gdev;
- struct gpio_chip *gc;
- int idx;
-};
-
-DEFINE_CLASS(gpio_chip_guard,
- struct gpio_chip_guard,
- srcu_read_unlock(&_T.gdev->srcu, _T.idx),
- ({
- struct gpio_chip_guard _guard;
-
- _guard.gdev = desc->gdev;
- _guard.idx = srcu_read_lock(&_guard.gdev->srcu);
- _guard.gc = srcu_dereference(_guard.gdev->chip,
- &_guard.gdev->srcu);
-
- _guard;
- }),
- struct gpio_desc *desc)
-
int gpiod_request(struct gpio_desc *desc, const char *label);
int gpiod_request_commit(struct gpio_desc *desc, const char *label);
void gpiod_free(struct gpio_desc *desc);
--
2.51.0