[PATCH v3 2/6] gpio: cdev: prepare gpio_desc_to_lineinfo() for being called from atomic

Bartosz Golaszewski
2024-10-15T10:56:36Z

From: Bartosz Golaszewski <bartosz.golaszewski@linaro.org>

In order to prepare gpio_desc_to_lineinfo() to being called from atomic
context, add a new argument - bool atomic - which, if set, indicates
that no sleeping functions must be called (currently: only
pinctrl_gpio_can_use_line()).

Signed-off-by: Bartosz Golaszewski <bartosz.golaszewski@linaro.org>
---
drivers/gpio/gpiolib-cdev.c | 15 +++++++++------
1 file changed, 9 insertions(+), 6 deletions(-)

diff --git a/drivers/gpio/gpiolib-cdev.c b/drivers/gpio/gpiolib-cdev.c
index b0050250ac3a..b28751242835 100644
--- a/drivers/gpio/gpiolib-cdev.c
+++ b/drivers/gpio/gpiolib-cdev.c
@@ -2361,7 +2361,7 @@ static void gpio_v2_line_info_changed_to_v1(
#endif /* CONFIG_GPIO_CDEV_V1 */

static void gpio_desc_to_lineinfo(struct gpio_desc *desc,
- struct gpio_v2_line_info *info)
+ struct gpio_v2_line_info *info, bool atomic)
{
unsigned long dflags;
const char *label;
@@ -2402,9 +2402,12 @@ static void gpio_desc_to_lineinfo(struct gpio_desc *desc,
test_bit(FLAG_USED_AS_IRQ, &dflags) ||
test_bit(FLAG_EXPORT, &dflags) ||
test_bit(FLAG_SYSFS, &dflags) ||
- !gpiochip_line_is_valid(guard.gc, info->offset) ||
- !pinctrl_gpio_can_use_line(guard.gc, info->offset))
+ !gpiochip_line_is_valid(guard.gc, info->offset)) {
info->flags |= GPIO_V2_LINE_FLAG_USED;
+ } else if (!atomic) {
+ if (!pinctrl_gpio_can_use_line(guard.gc, info->offset))
+ info->flags |= GPIO_V2_LINE_FLAG_USED;
+ }

if (test_bit(FLAG_IS_OUT, &dflags))
info->flags |= GPIO_V2_LINE_FLAG_OUTPUT;
@@ -2502,7 +2505,7 @@ static int lineinfo_get_v1(struct gpio_chardev_data *cdev, void __user *ip,
return -EBUSY;
}

- gpio_desc_to_lineinfo(desc, &lineinfo_v2);
+ gpio_desc_to_lineinfo(desc, &lineinfo_v2, false);
gpio_v2_line_info_to_v1(&lineinfo_v2, &lineinfo);

if (copy_to_user(ip, &lineinfo, sizeof(lineinfo))) {
@@ -2539,7 +2542,7 @@ static int lineinfo_get(struct gpio_chardev_data *cdev, void __user *ip,
if (test_and_set_bit(lineinfo.offset, cdev->watched_lines))
return -EBUSY;
}
- gpio_desc_to_lineinfo(desc, &lineinfo);
+ gpio_desc_to_lineinfo(desc, &lineinfo, false);
supinfo_to_lineinfo(desc, &lineinfo);

if (copy_to_user(ip, &lineinfo, sizeof(lineinfo))) {
@@ -2632,7 +2635,7 @@ static int lineinfo_changed_notify(struct notifier_block *nb,
memset(&chg, 0, sizeof(chg));
chg.event_type = action;
chg.timestamp_ns = ktime_get_ns();
- gpio_desc_to_lineinfo(desc, &chg.info);
+ gpio_desc_to_lineinfo(desc, &chg.info, false);
supinfo_to_lineinfo(desc, &chg.info);

ret = kfifo_in_spinlocked(&cdev->events, &chg, 1, &cdev->wait.lock);

--
2.43.0