gpio: sysfs: emit chardev line-state events on GPIO export

We already emit a CONFIG_RELEASED event when a line is unexported over
sysfs (this is handled by gpiod_free()) but we don't do the opposite
when it's exported. This adds the missing call to
gpiod_line_state_notify().

Reviewed-by: Kent Gibson <[email protected]>
Link: https://lore.kernel.org/r/[email protected]
Signed-off-by: Bartosz Golaszewski <[email protected]>

Author: Bartosz Golaszewski

drivers/gpio/gpiolib-sysfs.c

@@ -21,6 +21,8 @@
 #include <linux/gpio/consumer.h>
 #include <linux/gpio/driver.h>
 
+#include <uapi/linux/gpio.h>
+
 #include "gpiolib.h"
 #include "gpiolib-sysfs.h"
 
@@ -471,10 +473,12 @@ static ssize_t export_store(const struct class *class,
 	}
 
 	status = gpiod_export(desc, true);
-	if (status < 0)
+	if (status < 0) {
 		gpiod_free(desc);
-	else
+	} else {
 		set_bit(FLAG_SYSFS, &desc->flags);
+		gpiod_line_state_notify(desc, GPIO_V2_LINE_CHANGED_REQUESTED);
+	}
 
 done:
 	if (status)