summaryrefslogtreecommitdiffstats
path: root/include/linux/mux/driver.h
diff options
context:
space:
mode:
Diffstat (limited to 'include/linux/mux/driver.h')
-rw-r--r--include/linux/mux/driver.h105
1 files changed, 105 insertions, 0 deletions
diff --git a/include/linux/mux/driver.h b/include/linux/mux/driver.h
new file mode 100644
index 000000000..627a2c6bc
--- /dev/null
+++ b/include/linux/mux/driver.h
@@ -0,0 +1,105 @@
+/* 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/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.
+ *
+ * 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;
+};
+
+/**
+ * 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 */