1 files changed, 109 insertions, 0 deletions
diff --git a/include/linux/mux/driver.h b/include/linux/mux/driver.h
new file mode 100644
index 000000000..18824064f
--- /dev/null
+++ b/include/linux/mux/driver.h
@@ -0,0 +1,109 @@
+/* SPDX-License-Identifier: GPL-2.0 */
+/*
+ * mux/driver.h - definitions for the multiplexer driver interface
+ *
+ * Copyright (C) 2017 Axentia Technologies AB
+ *
+ * Author: Peter Rosin <peda@axentia.se>
+ */
+
+#ifndef _LINUX_MUX_DRIVER_H
+#define _LINUX_MUX_DRIVER_H
+
+#include <dt-bindings/mux/mux.h>
+#include <linux/device.h>
+#include <linux/ktime.h>
+#include <linux/semaphore.h>
+
+struct mux_chip;
+struct mux_control;
+
+/**
+ * struct mux_control_ops -	Mux controller operations for a mux chip.
+ * @set:			Set the state of the given mux controller.
+ */
+struct mux_control_ops {
+	int (*set)(struct mux_control *mux, int state);
+};
+
+/**
+ * struct mux_control -	Represents a mux controller.
+ * @lock:		Protects the mux controller state.
+ * @chip:		The mux chip that is handling this mux controller.
+ * @cached_state:	The current mux controller state, or -1 if none.
+ * @states:		The number of mux controller states.
+ * @idle_state:		The mux controller state to use when inactive, or one
+ *			of MUX_IDLE_AS_IS and MUX_IDLE_DISCONNECT.
+ * @last_change:	Timestamp of last change
+ *
+ * Mux drivers may only change @states and @idle_state, and may only do so
+ * between allocation and registration of the mux controller. Specifically,
+ * @cached_state is internal to the mux core and should never be written by
+ * mux drivers.
+ */
+struct mux_control {
+	struct semaphore lock; /* protects the state of the mux */
+
+	struct mux_chip *chip;
+	int cached_state;
+
+	unsigned int states;
+	int idle_state;
+
+	ktime_t last_change;
+};
+
+/**
+ * struct mux_chip -	Represents a chip holding mux controllers.
+ * @controllers:	Number of mux controllers handled by the chip.
+ * @mux:		Array of mux controllers that are handled.
+ * @dev:		Device structure.
+ * @id:			Used to identify the device internally.
+ * @ops:		Mux controller operations.
+ */
+struct mux_chip {
+	unsigned int controllers;
+	struct mux_control *mux;
+	struct device dev;
+	int id;
+
+	const struct mux_control_ops *ops;
+};
+
+#define to_mux_chip(x) container_of((x), struct mux_chip, dev)
+
+/**
+ * mux_chip_priv() - Get the extra memory reserved by mux_chip_alloc().
+ * @mux_chip: The mux-chip to get the private memory from.
+ *
+ * Return: Pointer to the private memory reserved by the allocator.
+ */
+static inline void *mux_chip_priv(struct mux_chip *mux_chip)
+{
+	return &mux_chip->mux[mux_chip->controllers];
+}
+
+struct mux_chip *mux_chip_alloc(struct device *dev,
+				unsigned int controllers, size_t sizeof_priv);
+int mux_chip_register(struct mux_chip *mux_chip);
+void mux_chip_unregister(struct mux_chip *mux_chip);
+void mux_chip_free(struct mux_chip *mux_chip);
+
+struct mux_chip *devm_mux_chip_alloc(struct device *dev,
+				     unsigned int controllers,
+				     size_t sizeof_priv);
+int devm_mux_chip_register(struct device *dev, struct mux_chip *mux_chip);
+
+/**
+ * mux_control_get_index() - Get the index of the given mux controller
+ * @mux: The mux-control to get the index for.
+ *
+ * Return: The index of the mux controller within the mux chip the mux
+ * controller is a part of.
+ */
+static inline unsigned int mux_control_get_index(struct mux_control *mux)
+{
+	return mux - mux->chip->mux;
+}
+
+#endif /* _LINUX_MUX_DRIVER_H */