1 files changed, 71 insertions, 0 deletions
diff --git a/drivers/gpio/gpiolib-shared.h b/drivers/gpio/gpiolib-shared.h
new file mode 100644
index 000000000000..667dbdff3585
--- /dev/null
+++ b/drivers/gpio/gpiolib-shared.h
@@ -0,0 +1,71 @@
+/* SPDX-License-Identifier: GPL-2.0 */
+
+#ifndef __LINUX_GPIO_SHARED_H
+#define __LINUX_GPIO_SHARED_H
+
+#include <linux/cleanup.h>
+#include <linux/lockdep.h>
+#include <linux/mutex.h>
+#include <linux/spinlock.h>
+
+struct gpio_device;
+struct gpio_desc;
+struct device;
+
+#if IS_ENABLED(CONFIG_GPIO_SHARED)
+
+int gpio_device_setup_shared(struct gpio_device *gdev);
+void gpio_device_teardown_shared(struct gpio_device *gdev);
+int gpio_shared_add_proxy_lookup(struct device *consumer, unsigned long lflags);
+
+#else
+
+static inline int gpio_device_setup_shared(struct gpio_device *gdev)
+{
+	return 0;
+}
+
+static inline void gpio_device_teardown_shared(struct gpio_device *gdev) { }
+
+static inline int gpio_shared_add_proxy_lookup(struct device *consumer,
+					       unsigned long lflags)
+{
+	return 0;
+}
+
+#endif /* CONFIG_GPIO_SHARED */
+
+struct gpio_shared_desc {
+	struct gpio_desc *desc;
+	bool can_sleep;
+	unsigned long cfg;
+	unsigned int usecnt;
+	unsigned int highcnt;
+	union {
+		struct mutex mutex;
+		spinlock_t spinlock;
+	};
+};
+
+struct gpio_shared_desc *devm_gpiod_shared_get(struct device *dev);
+
+DEFINE_LOCK_GUARD_1(gpio_shared_desc_lock, struct gpio_shared_desc,
+	if (_T->lock->can_sleep)
+		mutex_lock(&_T->lock->mutex);
+	else
+		spin_lock_irqsave(&_T->lock->spinlock, _T->flags),
+	if (_T->lock->can_sleep)
+		mutex_unlock(&_T->lock->mutex);
+	else
+		spin_unlock_irqrestore(&_T->lock->spinlock, _T->flags),
+	unsigned long flags)
+
+static inline void gpio_shared_lockdep_assert(struct gpio_shared_desc *shared_desc)
+{
+	if (shared_desc->can_sleep)
+		lockdep_assert_held(&shared_desc->mutex);
+	else
+		lockdep_assert_held(&shared_desc->spinlock);
+}
+
+#endif /* __LINUX_GPIO_SHARED_H */