289 lines
8.1 KiB
C

// SPDX-License-Identifier: Apache-2.0
#pragma once
#include "driver.h"
#include "error.h"
#include <stdbool.h>
#include <stddef.h>
#include <stdint.h>
#include <tactility/concurrent/mutex.h>
#include <tactility/freertos/freertos.h>
#ifdef __cplusplus
extern "C" {
#endif
struct Driver;
struct DeviceInternal;
/** Enables discovering devices of the same type */
struct DeviceType {
const char* name;
};
/** Represents a piece of hardware */
struct Device {
/** The name of the device. Valid characters: a-z a-Z 0-9 - _ . */
const char* name;
/** The configuration data for the device's driver */
const void* config;
/** The parent device that this device belongs to. Can be NULL, but only the root device should have a NULL parent. */
struct Device* parent;
/**
* Internal state managed by the kernel.
* Device implementers should initialize this to NULL.
* Do not access or modify directly; use device_* functions.
*/
struct DeviceInternal* internal;
};
/**
* Holds a device pointer and a compatible string.
* The device must not be constructed, added or started yet.
* This is used by the devicetree code generator and the application init sequence.
*/
struct CompatibleDevice {
struct Device* device;
const char* compatible;
};
/**
* Initialize the properties of a device.
*
* @param[in,out] device a device with all non-internal properties set
* @retval ERROR_OUT_OF_MEMORY if internal data allocation failed
* @retval ERROR_NONE on success
*/
error_t device_construct(struct Device* device);
/**
* Deinitialize the properties of a device.
* This fails when a device is busy or has children.
*
* @param[in,out] device non-null device pointer
* @retval ERROR_INVALID_STATE if the device is busy or has children
* @retval ERROR_NONE on success
*/
error_t device_destruct(struct Device* device);
/**
* Register a device to all relevant systems:
* - the global ledger
* - its parent (if any)
*
* @param[in,out] device non-null device pointer
* @retval ERROR_INVALID_STATE if the device is already added
* @retval ERROR_NONE on success
*/
error_t device_add(struct Device* device);
/**
* Deregister a device. Remove it from all relevant systems:
* - the global ledger
* - its parent (if any)
*
* @param[in,out] device non-null device pointer
* @retval ERROR_INVALID_STATE if the device is still started
* @retval ERROR_NOT_FOUND if the device was not found in the system
* @retval ERROR_NONE on success
*/
error_t device_remove(struct Device* device);
/**
* Attach the driver.
*
* @warning must call device_construct() and device_add() first
* @param[in,out] device non-null device pointer
* @retval ERROR_INVALID_STATE if the device is already started or not added
* @retval ERROR_RESOURCE when driver binding fails
* @retval ERROR_NONE on success
*/
error_t device_start(struct Device* device);
/**
* Detach the driver.
*
* @param[in,out] device non-null device pointer
* @retval ERROR_INVALID_STATE if the device is not started
* @retval ERROR_RESOURCE when driver unbinding fails
* @retval ERROR_NONE on success
*/
error_t device_stop(struct Device* device);
/**
* Construct and add a device with the given compatible string.
*
* @param[in,out] device non-NULL device
* @param[in] compatible compatible string
* @retval ERROR_NONE on success
* @retval error_t error code on failure
*/
error_t device_construct_add_start(struct Device* device, const char* compatible);
/**
* Construct and add a device with the given compatible string.
*
* @param[in,out] device non-NULL device
* @param[in] compatible compatible string
* @retval ERROR_NONE on success
* @retval error_t error code on failure
*/
error_t device_construct_add(struct Device* device, const char* compatible);
/**
* Set or unset a parent.
*
* @warning must call before device_add()
* @param[in,out] device non-NULL device
* @param[in] parent nullable parent device
*/
void device_set_parent(struct Device* device, struct Device* parent);
/**
* Set the driver for a device.
*
* @warning must call before device_add()
* @param[in,out] device non-NULL device
* @param[in] driver nullable driver
*/
void device_set_driver(struct Device* device, struct Driver* driver);
/**
* Get the driver for a device.
*
* @param[in] device non-null device pointer
* @return the driver, or NULL if the device has no driver
*/
struct Driver* device_get_driver(struct Device* device);
/**
* Get the parent device of a device.
*
* @param[in] device non-null device pointer
* @return the parent device, or NULL if the device has no parent
*/
struct Device* device_get_parent(struct Device* device);
/**
* Indicates whether the device is in a state where its API is available
*
* @param[in] device non-null device pointer
* @return true if the device is ready for use
*/
bool device_is_ready(const struct Device* device);
/**
* Indicates whether the device is compatible with the given compatible string.
* @param[in] device non-null device pointer
* @param[in] compatible compatible string
* @return true if the device is compatible
*/
bool device_is_compatible(const struct Device* device, const char* compatible);
/**
* Set the driver data for a device.
*
* @param[in,out] device non-null device pointer
* @param[in] driver_data the driver data
*/
void device_set_driver_data(struct Device* device, void* driver_data);
/**
* Get the driver data for a device.
*
* @param[in] device non-null device pointer
* @return the driver data
*/
void* device_get_driver_data(struct Device* device);
/**
* Indicates whether the device has been added to the system.
*
* @param[in] device non-null device pointer
* @return true if the device has been added
*/
bool device_is_added(const struct Device* device);
/**
* Lock the device for exclusive access.
*
* @param[in,out] device non-null device pointer
*/
void device_lock(struct Device* device);
/**
* Try to lock the device for exclusive access.
*
* @param[in,out] device non-null device pointer
* @param[in] timeout how long to wait for the lock
* @return true if the device was locked successfully
*/
bool device_try_lock(struct Device* device, TickType_t timeout);
/**
* Unlock the device.
*
* @param[in,out] device non-null device pointer
*/
void device_unlock(struct Device* device);
/**
* Get the type of a device.
*
* @param[in] device non-null device pointer
* @return the device type
*/
const struct DeviceType* device_get_type(struct Device* device);
/**
* Iterate through all the known devices
*
* @param[in] callback_context the parameter to pass to the callback. NULL is valid.
* @param[in] on_device the function to call for each filtered device. return true to continue iterating or false to stop.
*/
void device_for_each(void* callback_context, bool(*on_device)(struct Device* device, void* context));
/**
* Iterate through all the child devices of the specified device
*
* @param[in] device non-null device pointer
* @param[in] callback_context the parameter to pass to the callback. NULL is valid.
* @param[in] on_device the function to call for each filtered device. return true to continue iterating or false to stop.
*/
void device_for_each_child(struct Device* device, void* callback_context, bool(*on_device)(struct Device* device, void* context));
/**
* Iterate through all the known devices of a specific type
*
* @param[in] type the type to filter
* @param[in] callback_context the parameter to pass to the callback. NULL is valid.
* @param[in] on_device the function to call for each filtered device. return true to continue iterating or false to stop.
*/
void device_for_each_of_type(const struct DeviceType* type, void* callback_context, bool(*on_device)(struct Device* device, void* context));
/**
* Check if a device of the specified type exists.
*
* @param[in] type the type to check
* @return true if a device of the specified type exists
*/
bool device_exists_of_type(const struct DeviceType* type);
/**
* Find a device by its name.
*
* @param[in] name non-null device name to look up
* @return the device pointer if found, or NULL if not found
*/
struct Device* device_find_by_name(const char* name);
#ifdef __cplusplus
}
#endif