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pigweed / third_party / github / zephyrproject-rtos / zephyr / 98d0a2bb34e3b6c4c094e5ffb7ccc7bea7395152 / . / include / zephyr / device.h
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/*
* Copyright (c) 2015 Intel Corporation.
*
* SPDX-License-Identifier: Apache-2.0
*/
#ifndef ZEPHYR_INCLUDE_DEVICE_H_
#define ZEPHYR_INCLUDE_DEVICE_H_
#include <stdint.h>
#include <zephyr/devicetree.h>
#include <zephyr/init.h>
#include <zephyr/linker/sections.h>
#include <zephyr/pm/state.h>
#include <zephyr/sys/device_mmio.h>
#include <zephyr/sys/iterable_sections.h>
#include <zephyr/sys/util.h>
#include <zephyr/toolchain.h>
#ifdef CONFIG_LLEXT
#include <zephyr/llext/symbol.h>
#endif
#ifdef __cplusplus
extern "C" {
#endif
/**
* @brief Device Model
* @defgroup device_model Device Model
* @since 1.0
* @version 1.1.0
* @{
*/
/** @cond INTERNAL_HIDDEN */
/**
* @brief Flag value used in lists of device dependencies to separate distinct
* groups.
*/
#define Z_DEVICE_DEPS_SEP INT16_MIN
/**
* @brief Flag value used in lists of device dependencies to indicate the end of
* the list.
*/
#define Z_DEVICE_DEPS_ENDS INT16_MAX
/** @brief Determine if a DT node is mutable */
#define Z_DEVICE_IS_MUTABLE(node_id) \
COND_CODE_1(IS_ENABLED(CONFIG_DEVICE_MUTABLE), (DT_PROP(node_id, zephyr_mutable)), (0))
/** @endcond */
/**
* @brief Type used to represent a "handle" for a device.
*
* Every @ref device has an associated handle. You can get a pointer to a
* @ref device from its handle and vice versa, but the handle uses less space
* than a pointer. The device.h API mainly uses handles to store lists of
* multiple devices in a compact way.
*
* The extreme values and zero have special significance. Negative values
* identify functionality that does not correspond to a Zephyr device, such as
* the system clock or a SYS_INIT() function.
*
* @see device_handle_get()
* @see device_from_handle()
*/
typedef int16_t device_handle_t;
/** @brief Flag value used to identify an unknown device. */
#define DEVICE_HANDLE_NULL 0
/**
* @brief Expands to the name of a global device object.
*
* Return the full name of a device object symbol created by DEVICE_DEFINE(),
* using the `dev_id` provided to DEVICE_DEFINE(). This is the name of the
* global variable storing the device structure, not a pointer to the string in
* the @ref device.name field.
*
* It is meant to be used for declaring extern symbols pointing to device
* objects before using the DEVICE_GET macro to get the device object.
*
* This macro is normally only useful within device driver source code. In other
* situations, you are probably looking for device_get_binding().
*
* @param dev_id Device identifier.
*
* @return The full name of the device object defined by device definition
* macros.
*/
#define DEVICE_NAME_GET(dev_id) _CONCAT(__device_, dev_id)
/* This macro synthesizes a unique dev_id from a devicetree node by using
* the node's dependency ordinal.
*
* The ordinal used in this name can be mapped to the path by
* examining zephyr/include/generated/zephyr/devicetree_generated.h.
*/
#define Z_DEVICE_DT_DEV_ID(node_id) _CONCAT(dts_ord_, DT_DEP_ORD(node_id))
#if defined(CONFIG_LLEXT_EXPORT_DEVICES)
/* Export device identifiers using the builtin name */
#define Z_DEVICE_EXPORT(node_id) EXPORT_SYMBOL(DEVICE_DT_NAME_GET(node_id))
#endif
/**
* @brief Create a device object and set it up for boot time initialization.
*
* This macro defines a @ref device that is automatically configured by the
* kernel during system initialization. This macro should only be used when the
* device is not being allocated from a devicetree node. If you are allocating a
* device from a devicetree node, use DEVICE_DT_DEFINE() or
* DEVICE_DT_INST_DEFINE() instead.
*
* @param dev_id A unique token which is used in the name of the global device
* structure as a C identifier.
* @param name A string name for the device, which will be stored in
* @ref device.name. This name can be used to look up the device with
* device_get_binding(). This must be less than Z_DEVICE_MAX_NAME_LEN characters
* (including terminating `NULL`) in order to be looked up from user mode.
* @param init_fn Pointer to the device's initialization function, which will be
* run by the kernel during system initialization. Can be `NULL`.
* @param pm Pointer to the device's power management resources, a
* @ref pm_device, which will be stored in @ref device.pm field. Use `NULL` if
* the device does not use PM.
* @param data Pointer to the device's private mutable data, which will be
* stored in @ref device.data.
* @param config Pointer to the device's private constant data, which will be
* stored in @ref device.config.
* @param level The device's initialization level (PRE_KERNEL_1, PRE_KERNEL_2 or
* POST_KERNEL).
* @param prio The device's priority within its initialization level. See
* SYS_INIT() for details.
* @param api Pointer to the device's API structure. Can be `NULL`.
*/
#define DEVICE_DEFINE(dev_id, name, init_fn, pm, data, config, level, prio, \
api) \
Z_DEVICE_STATE_DEFINE(dev_id); \
Z_DEVICE_DEFINE(DT_INVALID_NODE, dev_id, name, init_fn, pm, data, \
config, level, prio, api, \
&Z_DEVICE_STATE_NAME(dev_id))
/**
* @brief Return a string name for a devicetree node.
*
* This macro returns a string literal usable as a device's name from a
* devicetree node identifier.
*
* @param node_id The devicetree node identifier.
*
* @return The value of the node's `label` property, if it has one.
* Otherwise, the node's full name in `node-name@unit-address` form.
*/
#define DEVICE_DT_NAME(node_id) \
DT_PROP_OR(node_id, label, DT_NODE_FULL_NAME(node_id))
/**
* @brief Determine if a devicetree node initialization should be deferred.
*
* @param node_id The devicetree node identifier.
*
* @return Boolean stating if node initialization should be deferred.
*/
#define DEVICE_DT_DEFER(node_id) \
DT_PROP(node_id, zephyr_deferred_init)
/**
* @brief Create a device object from a devicetree node identifier and set it up
* for boot time initialization.
*
* This macro defines a @ref device that is automatically configured by the
* kernel during system initialization. The global device object's name as a C
* identifier is derived from the node's dependency ordinal. @ref device.name is
* set to `DEVICE_DT_NAME(node_id)`.
*
* The device is declared with extern visibility, so a pointer to a global
* device object can be obtained with `DEVICE_DT_GET(node_id)` from any source
* file that includes `<zephyr/device.h>` (even from extensions, when
* @kconfig{CONFIG_LLEXT_EXPORT_DEVICES} is enabled). Before using the
* pointer, the referenced object should be checked using device_is_ready().
*
* @param node_id The devicetree node identifier.
* @param init_fn Pointer to the device's initialization function, which will be
* run by the kernel during system initialization. Can be `NULL`.
* @param pm Pointer to the device's power management resources, a
* @ref pm_device, which will be stored in @ref device.pm. Use `NULL` if the
* device does not use PM.
* @param data Pointer to the device's private mutable data, which will be
* stored in @ref device.data.
* @param config Pointer to the device's private constant data, which will be
* stored in @ref device.config field.
* @param level The device's initialization level (PRE_KERNEL_1, PRE_KERNEL_2 or
* POST_KERNEL).
* @param prio The device's priority within its initialization level. See
* SYS_INIT() for details.
* @param api Pointer to the device's API structure. Can be `NULL`.
*/
#define DEVICE_DT_DEFINE(node_id, init_fn, pm, data, config, level, prio, api, \
...) \
Z_DEVICE_STATE_DEFINE(Z_DEVICE_DT_DEV_ID(node_id)); \
Z_DEVICE_DEFINE(node_id, Z_DEVICE_DT_DEV_ID(node_id), \
DEVICE_DT_NAME(node_id), init_fn, pm, data, config, \
level, prio, api, \
&Z_DEVICE_STATE_NAME(Z_DEVICE_DT_DEV_ID(node_id)), \
__VA_ARGS__) \
IF_ENABLED(CONFIG_LLEXT_EXPORT_DEVICES, (Z_DEVICE_EXPORT(node_id);))
/**
* @brief Like DEVICE_DT_DEFINE(), but uses an instance of a `DT_DRV_COMPAT`
* compatible instead of a node identifier.
*
* @param inst Instance number. The `node_id` argument to DEVICE_DT_DEFINE() is
* set to `DT_DRV_INST(inst)`.
* @param ... Other parameters as expected by DEVICE_DT_DEFINE().
*/
#define DEVICE_DT_INST_DEFINE(inst, ...) \
DEVICE_DT_DEFINE(DT_DRV_INST(inst), __VA_ARGS__)
/**
* @brief The name of the global device object for @p node_id
*
* Returns the name of the global device structure as a C identifier. The device
* must be allocated using DEVICE_DT_DEFINE() or DEVICE_DT_INST_DEFINE() for
* this to work.
*
* This macro is normally only useful within device driver source code. In other
* situations, you are probably looking for DEVICE_DT_GET().
*
* @param node_id Devicetree node identifier
*
* @return The name of the device object as a C identifier
*/
#define DEVICE_DT_NAME_GET(node_id) DEVICE_NAME_GET(Z_DEVICE_DT_DEV_ID(node_id))
/**
* @brief Get a @ref device reference from a devicetree node identifier.
*
* Returns a pointer to a device object created from a devicetree node, if any
* device was allocated by a driver.
*
* If no such device was allocated, this will fail at linker time. If you get an
* error that looks like `undefined reference to __device_dts_ord_<N>`, that is
* what happened. Check to make sure your device driver is being compiled,
* usually by enabling the Kconfig options it requires.
*
* @param node_id A devicetree node identifier
*
* @return A pointer to the device object created for that node
*/
#define DEVICE_DT_GET(node_id) (&DEVICE_DT_NAME_GET(node_id))
/**
* @brief Get a @ref device reference for an instance of a `DT_DRV_COMPAT`
* compatible.
*
* This is equivalent to `DEVICE_DT_GET(DT_DRV_INST(inst))`.
*
* @param inst `DT_DRV_COMPAT` instance number
* @return A pointer to the device object created for that instance
*/
#define DEVICE_DT_INST_GET(inst) DEVICE_DT_GET(DT_DRV_INST(inst))
/**
* @brief Get a @ref device reference from a devicetree compatible.
*
* If an enabled devicetree node has the given compatible and a device
* object was created from it, this returns a pointer to that device.
*
* If there no such devices, this returns NULL.
*
* If there are multiple, this returns an arbitrary one.
*
* If this returns non-NULL, the device must be checked for readiness
* before use, e.g. with device_is_ready().
*
* @param compat lowercase-and-underscores devicetree compatible
* @return a pointer to a device, or NULL
*/
#define DEVICE_DT_GET_ANY(compat) \
COND_CODE_1(DT_HAS_COMPAT_STATUS_OKAY(compat), \
(DEVICE_DT_GET(DT_COMPAT_GET_ANY_STATUS_OKAY(compat))), \
(NULL))
/**
* @brief Get a @ref device reference from a devicetree compatible.
*
* If an enabled devicetree node has the given compatible and a device object
* was created from it, this returns a pointer to that device.
*
* If there are no such devices, this will fail at compile time.
*
* If there are multiple, this returns an arbitrary one.
*
* If this returns non-NULL, the device must be checked for readiness before
* use, e.g. with device_is_ready().
*
* @param compat lowercase-and-underscores devicetree compatible
* @return a pointer to a device
*/
#define DEVICE_DT_GET_ONE(compat) \
COND_CODE_1(DT_HAS_COMPAT_STATUS_OKAY(compat), \
(DEVICE_DT_GET(DT_COMPAT_GET_ANY_STATUS_OKAY(compat))), \
(ZERO_OR_COMPILE_ERROR(0)))
/**
* @brief Utility macro to obtain an optional reference to a device.
*
* If the node identifier refers to a node with status `okay`, this returns
* `DEVICE_DT_GET(node_id)`. Otherwise, it returns `NULL`.
*
* @param node_id devicetree node identifier
*
* @return a @ref device reference for the node identifier, which may be `NULL`.
*/
#define DEVICE_DT_GET_OR_NULL(node_id) \
COND_CODE_1(DT_NODE_HAS_STATUS_OKAY(node_id), \
(DEVICE_DT_GET(node_id)), (NULL))
/**
* @brief Obtain a pointer to a device object by name
*
* @details Return the address of a device object created by
* DEVICE_DEFINE(), using the dev_id provided to DEVICE_DEFINE().
*
* @param dev_id Device identifier.
*
* @return A pointer to the device object created by DEVICE_DEFINE()
*/
#define DEVICE_GET(dev_id) (&DEVICE_NAME_GET(dev_id))
/**
* @brief Declare a static device object
*
* This macro can be used at the top-level to declare a device, such
* that DEVICE_GET() may be used before the full declaration in
* DEVICE_DEFINE().
*
* This is often useful when configuring interrupts statically in a
* device's init or per-instance config function, as the init function
* itself is required by DEVICE_DEFINE() and use of DEVICE_GET()
* inside it creates a circular dependency.
*
* @param dev_id Device identifier.
*/
#define DEVICE_DECLARE(dev_id) \
static const struct device DEVICE_NAME_GET(dev_id)
/**
* @brief Get a @ref init_entry reference from a devicetree node.
*
* @param node_id A devicetree node identifier
*
* @return A pointer to the @ref init_entry object created for that node
*/
#define DEVICE_INIT_DT_GET(node_id) \
(&Z_INIT_ENTRY_NAME(DEVICE_DT_NAME_GET(node_id)))
/**
* @brief Get a @ref init_entry reference from a device identifier.
*
* @param dev_id Device identifier.
*
* @return A pointer to the init_entry object created for that device
*/
#define DEVICE_INIT_GET(dev_id) (&Z_INIT_ENTRY_NAME(DEVICE_NAME_GET(dev_id)))
/**
* @brief Runtime device dynamic structure (in RAM) per driver instance
*
* Fields in this are expected to be default-initialized to zero. The
* kernel driver infrastructure and driver access functions are
* responsible for ensuring that any non-zero initialization is done
* before they are accessed.
*/
struct device_state {
/**
* Device initialization return code (positive errno value).
*
* Device initialization functions return a negative errno code if they
* fail. In Zephyr, errno values do not exceed 255, so we can store the
* positive result value in a uint8_t type.
*/
uint8_t init_res;
/** Indicates the device initialization function has been
* invoked.
*/
bool initialized : 1;
};
struct pm_device_base;
struct pm_device;
struct pm_device_isr;
#if defined(CONFIG_DEVICE_DT_METADATA) || defined(__DOXYGEN__)
struct device_dt_metadata;
#endif
#ifdef CONFIG_DEVICE_DEPS_DYNAMIC
#define Z_DEVICE_DEPS_CONST
#else
#define Z_DEVICE_DEPS_CONST const
#endif
/**
* @brief Runtime device structure (in ROM) per driver instance
*/
struct device {
/** Name of the device instance */
const char *name;
/** Address of device instance config information */
const void *config;
/** Address of the API structure exposed by the device instance */
const void *api;
/** Address of the common device state */
struct device_state *state;
/** Address of the device instance private data */
void *data;
#if defined(CONFIG_DEVICE_DEPS) || defined(__DOXYGEN__)
/**
* Optional pointer to dependencies associated with the device.
*
* This encodes a sequence of sets of device handles that have some
* relationship to this node. The individual sets are extracted with
* dedicated API, such as device_required_handles_get(). Only available
* if @kconfig{CONFIG_DEVICE_DEPS} is enabled.
*/
Z_DEVICE_DEPS_CONST device_handle_t *deps;
#endif /* CONFIG_DEVICE_DEPS */
#if defined(CONFIG_PM_DEVICE) || defined(__DOXYGEN__)
/**
* Reference to the device PM resources (only available if
* @kconfig{CONFIG_PM_DEVICE} is enabled).
*/
union {
struct pm_device_base *pm_base;
struct pm_device *pm;
struct pm_device_isr *pm_isr;
};
#endif
#if defined(CONFIG_DEVICE_DT_METADATA) || defined(__DOXYGEN__)
const struct device_dt_metadata *dt_meta;
#endif /* CONFIG_DEVICE_DT_METADATA */
};
/**
* @brief Get the handle for a given device
*
* @param dev the device for which a handle is desired.
*
* @return the handle for the device, or DEVICE_HANDLE_NULL if the device does
* not have an associated handle.
*/
static inline device_handle_t device_handle_get(const struct device *dev)
{
device_handle_t ret = DEVICE_HANDLE_NULL;
STRUCT_SECTION_START_EXTERN(device);
/* TODO: If/when devices can be constructed that are not part of the
* fixed sequence we'll need another solution.
*/
if (dev != NULL) {
ret = 1 + (device_handle_t)(dev - STRUCT_SECTION_START(device));
}
return ret;
}
/**
* @brief Get the device corresponding to a handle.
*
* @param dev_handle the device handle
*
* @return the device that has that handle, or a null pointer if @p dev_handle
* does not identify a device.
*/
static inline const struct device *
device_from_handle(device_handle_t dev_handle)
{
STRUCT_SECTION_START_EXTERN(device);
const struct device *dev = NULL;
size_t numdev;
STRUCT_SECTION_COUNT(device, &numdev);
if ((dev_handle > 0) && ((size_t)dev_handle <= numdev)) {
dev = &STRUCT_SECTION_START(device)[dev_handle - 1];
}
return dev;
}
#if defined(CONFIG_DEVICE_DEPS) || defined(__DOXYGEN__)
/**
* @brief Prototype for functions used when iterating over a set of devices.
*
* Such a function may be used in API that identifies a set of devices and
* provides a visitor API supporting caller-specific interaction with each
* device in the set.
*
* The visit is said to succeed if the visitor returns a non-negative value.
*
* @param dev a device in the set being iterated
* @param context state used to support the visitor function
*
* @return A non-negative number to allow walking to continue, and a negative
* error code to case the iteration to stop.
*
* @see device_required_foreach()
* @see device_supported_foreach()
*/
typedef int (*device_visitor_callback_t)(const struct device *dev,
void *context);
/**
* @brief Get the device handles for devicetree dependencies of this device.
*
* This function returns a pointer to an array of device handles. The length of
* the array is stored in the @p count parameter.
*
* The array contains a handle for each device that @p dev requires directly, as
* determined from the devicetree. This does not include transitive
* dependencies; you must recursively determine those.
*
* @param dev the device for which dependencies are desired.
* @param count pointer to where this function should store the length of the
* returned array. No value is stored if the call returns a null pointer. The
* value may be set to zero if the device has no devicetree dependencies.
*
* @return a pointer to a sequence of @p count device handles, or a null pointer
* if @p dev does not have any dependency data.
*/
static inline const device_handle_t *
device_required_handles_get(const struct device *dev, size_t *count)
{
const device_handle_t *rv = dev->deps;
if (rv != NULL) {
size_t i = 0;
while ((rv[i] != Z_DEVICE_DEPS_ENDS) &&
(rv[i] != Z_DEVICE_DEPS_SEP)) {
++i;
}
*count = i;
}
return rv;
}
/**
* @brief Get the device handles for injected dependencies of this device.
*
* This function returns a pointer to an array of device handles. The length of
* the array is stored in the @p count parameter.
*
* The array contains a handle for each device that @p dev manually injected as
* a dependency, via providing extra arguments to Z_DEVICE_DEFINE. This does not
* include transitive dependencies; you must recursively determine those.
*
* @param dev the device for which injected dependencies are desired.
* @param count pointer to where this function should store the length of the
* returned array. No value is stored if the call returns a null pointer. The
* value may be set to zero if the device has no devicetree dependencies.
*
* @return a pointer to a sequence of @p *count device handles, or a null
* pointer if @p dev does not have any dependency data.
*/
static inline const device_handle_t *
device_injected_handles_get(const struct device *dev, size_t *count)
{
const device_handle_t *rv = dev->deps;
size_t region = 0;
size_t i = 0;
if (rv != NULL) {
/* Fast forward to injected devices */
while (region != 1) {
if (*rv == Z_DEVICE_DEPS_SEP) {
region++;
}
rv++;
}
while ((rv[i] != Z_DEVICE_DEPS_ENDS) &&
(rv[i] != Z_DEVICE_DEPS_SEP)) {
++i;
}
*count = i;
}
return rv;
}
/**
* @brief Get the set of handles that this device supports.
*
* This function returns a pointer to an array of device handles. The length of
* the array is stored in the @p count parameter.
*
* The array contains a handle for each device that @p dev "supports" -- that
* is, devices that require @p dev directly -- as determined from the
* devicetree. This does not include transitive dependencies; you must
* recursively determine those.
*
* @param dev the device for which supports are desired.
* @param count pointer to where this function should store the length of the
* returned array. No value is stored if the call returns a null pointer. The
* value may be set to zero if nothing in the devicetree depends on @p dev.
*
* @return a pointer to a sequence of @p *count device handles, or a null
* pointer if @p dev does not have any dependency data.
*/
static inline const device_handle_t *
device_supported_handles_get(const struct device *dev, size_t *count)
{
const device_handle_t *rv = dev->deps;
size_t region = 0;
size_t i = 0;
if (rv != NULL) {
/* Fast forward to supporting devices */
while (region != 2) {
if (*rv == Z_DEVICE_DEPS_SEP) {
region++;
}
rv++;
}
/* Count supporting devices.
* Trailing NULL's can be injected by gen_device_deps.py due to
* CONFIG_PM_DEVICE_POWER_DOMAIN_DYNAMIC_NUM
*/
while ((rv[i] != Z_DEVICE_DEPS_ENDS) &&
(rv[i] != DEVICE_HANDLE_NULL)) {
++i;
}
*count = i;
}
return rv;
}
/**
* @brief Visit every device that @p dev directly requires.
*
* Zephyr maintains information about which devices are directly required by
* another device; for example an I2C-based sensor driver will require an I2C
* controller for communication. Required devices can derive from
* statically-defined devicetree relationships or dependencies registered at
* runtime.
*
* This API supports operating on the set of required devices. Example uses
* include making sure required devices are ready before the requiring device is
* used, and releasing them when the requiring device is no longer needed.
*
* There is no guarantee on the order in which required devices are visited.
*
* If the @p visitor_cb function returns a negative value iteration is halted,
* and the returned value from the visitor is returned from this function.
*
* @note This API is not available to unprivileged threads.
*
* @param dev a device of interest. The devices that this device depends on will
* be used as the set of devices to visit. This parameter must not be null.
* @param visitor_cb the function that should be invoked on each device in the
* dependency set. This parameter must not be null.
* @param context state that is passed through to the visitor function. This
* parameter may be null if @p visitor_cb tolerates a null @p context.
*
* @return The number of devices that were visited if all visits succeed, or
* the negative value returned from the first visit that did not succeed.
*/
int device_required_foreach(const struct device *dev,
device_visitor_callback_t visitor_cb,
void *context);
/**
* @brief Visit every device that @p dev directly supports.
*
* Zephyr maintains information about which devices are directly supported by
* another device; for example an I2C controller will support an I2C-based
* sensor driver. Supported devices can derive from statically-defined
* devicetree relationships.
*
* This API supports operating on the set of supported devices. Example uses
* include iterating over the devices connected to a regulator when it is
* powered on.
*
* There is no guarantee on the order in which required devices are visited.
*
* If the @p visitor_cb function returns a negative value iteration is halted,
* and the returned value from the visitor is returned from this function.
*
* @note This API is not available to unprivileged threads.
*
* @param dev a device of interest. The devices that this device supports
* will be used as the set of devices to visit. This parameter must not be null.
* @param visitor_cb the function that should be invoked on each device in the
* support set. This parameter must not be null.
* @param context state that is passed through to the visitor function. This
* parameter may be null if @p visitor_cb tolerates a null @p context.
*
* @return The number of devices that were visited if all visits succeed, or the
* negative value returned from the first visit that did not succeed.
*/
int device_supported_foreach(const struct device *dev,
device_visitor_callback_t visitor_cb,
void *context);
#endif /* CONFIG_DEVICE_DEPS */
/**
* @brief Get a @ref device reference from its @ref device.name field.
*
* This function iterates through the devices on the system. If a device with
* the given @p name field is found, and that device initialized successfully at
* boot time, this function returns a pointer to the device.
*
* If no device has the given @p name, this function returns `NULL`.
*
* This function also returns NULL when a device is found, but it failed to
* initialize successfully at boot time. (To troubleshoot this case, set a
* breakpoint on your device driver's initialization function.)
*
* @param name device name to search for. A null pointer, or a pointer to an
* empty string, will cause NULL to be returned.
*
* @return pointer to device structure with the given name; `NULL` if the device
* is not found or if the device with that name's initialization function
* failed.
*/
__syscall const struct device *device_get_binding(const char *name);
/**
* @brief Get access to the static array of static devices.
*
* @param devices where to store the pointer to the array of statically
* allocated devices. The array must not be mutated through this pointer.
*
* @return the number of statically allocated devices.
*/
size_t z_device_get_all_static(const struct device **devices);
/**
* @brief Verify that a device is ready for use.
*
* Indicates whether the provided device pointer is for a device known to be
* in a state where it can be used with its standard API.
*
* This can be used with device pointers captured from DEVICE_DT_GET(), which
* does not include the readiness checks of device_get_binding(). At minimum
* this means that the device has been successfully initialized.
*
* @param dev pointer to the device in question.
*
* @retval true If the device is ready for use.
* @retval false If the device is not ready for use or if a NULL device pointer
* is passed as argument.
*/
__syscall bool device_is_ready(const struct device *dev);
/**
* @brief Initialize a device.
*
* A device whose initialization was deferred (by marking it as
* ``zephyr,deferred-init`` on devicetree) needs to be initialized manually via
* this call. Note that only devices whose initialization was deferred can be
* initialized via this call - one can not try to initialize a non
* initialization deferred device that failed initialization with this call.
*
* @param dev device to be initialized.
*
* @retval -ENOENT If device was not found - or isn't a deferred one.
* @retval -errno For other errors.
*/
__syscall int device_init(const struct device *dev);
/**
* @}
*/
/** @cond INTERNAL_HIDDEN */
/**
* @brief Synthesize a unique name for the device state associated with
* @p dev_id.
*/
#define Z_DEVICE_STATE_NAME(dev_id) _CONCAT(__devstate_, dev_id)
/**
* @brief Utility macro to define and initialize the device state.
*
* @param dev_id Device identifier.
*/
#define Z_DEVICE_STATE_DEFINE(dev_id) \
static Z_DECL_ALIGN(struct device_state) Z_DEVICE_STATE_NAME(dev_id) \
__attribute__((__section__(".z_devstate")))
#if defined(CONFIG_DEVICE_DEPS) || defined(__DOXYGEN__)
/**
* @brief Synthesize the name of the object that holds device ordinal and
* dependency data.
*
* @param dev_id Device identifier.
*/
#define Z_DEVICE_DEPS_NAME(dev_id) _CONCAT(__devicedeps_, dev_id)
/**
* @brief Expand extra dependencies with a comma in between.
*
* @param ... Extra dependencies.
*/
#define Z_DEVICE_EXTRA_DEPS(...) \
FOR_EACH_NONEMPTY_TERM(IDENTITY, (,), __VA_ARGS__)
/** @brief Linker section were device dependencies are placed. */
#define Z_DEVICE_DEPS_SECTION \
__attribute__((__section__(".__device_deps_pass1")))
#ifdef __cplusplus
#define Z_DEVICE_DEPS_EXTERN extern
#else
#define Z_DEVICE_DEPS_EXTERN
#endif
/**
* @brief Define device dependencies.
*
* Initial build provides a record that associates the device object with its
* devicetree ordinal, and provides the dependency ordinals. These are provided
* as weak definitions (to prevent the reference from being captured when the
* original object file is compiled), and in a distinct pass1 section (which
* will be replaced by postprocessing).
*
* Before processing in gen_device_deps.py, the array format is:
* {
* DEVICE_ORDINAL (or DEVICE_HANDLE_NULL if not a devicetree node),
* List of devicetree dependency ordinals (if any),
* Z_DEVICE_DEPS_SEP,
* List of injected dependency ordinals (if any),
* Z_DEVICE_DEPS_SEP,
* List of devicetree supporting ordinals (if any),
* }
*
* After processing in gen_device_deps.py, the format is updated to:
* {
* List of existing devicetree dependency handles (if any),
* Z_DEVICE_DEPS_SEP,
* List of injected devicetree dependency handles (if any),
* Z_DEVICE_DEPS_SEP,
* List of existing devicetree support handles (if any),
* DEVICE_HANDLE_NULL
* }
*
* It is also (experimentally) necessary to provide explicit alignment on each
* object. Otherwise x86-64 builds will introduce padding between objects in the
* same input section in individual object files, which will be retained in
* subsequent links both wasting space and resulting in aggregate size changes
* relative to pass2 when all objects will be in the same input section.
*/
#define Z_DEVICE_DEPS_DEFINE(node_id, dev_id, ...) \
extern Z_DEVICE_DEPS_CONST device_handle_t Z_DEVICE_DEPS_NAME( \
dev_id)[]; \
Z_DEVICE_DEPS_CONST Z_DECL_ALIGN(device_handle_t) \
Z_DEVICE_DEPS_SECTION Z_DEVICE_DEPS_EXTERN __weak \
Z_DEVICE_DEPS_NAME(dev_id)[] = { \
COND_CODE_1( \
DT_NODE_EXISTS(node_id), \
(DT_DEP_ORD(node_id), DT_REQUIRES_DEP_ORDS(node_id)), \
(DEVICE_HANDLE_NULL,)) /**/ \
Z_DEVICE_DEPS_SEP, \
Z_DEVICE_EXTRA_DEPS(__VA_ARGS__) /**/ \
Z_DEVICE_DEPS_SEP, \
COND_CODE_1(DT_NODE_EXISTS(node_id), \
(DT_SUPPORTS_DEP_ORDS(node_id)), ()) /**/ \
}
#endif /* CONFIG_DEVICE_DEPS */
#if defined(CONFIG_DEVICE_DT_METADATA) || defined(__DOXYGEN__)
/**
* @brief Devicetree node labels associated with a device
*/
struct device_dt_nodelabels {
/* @brief number of elements in the nodelabels array */
size_t num_nodelabels;
/* @brief array of node labels as strings, exactly as they
* appear in the final devicetree
*/
const char *nodelabels[];
};
/**
* @brief Devicetree metadata associated with a device
*
* This is currently limited to node labels, but the structure is
* generic enough to be extended later without requiring breaking
* changes.
*/
struct device_dt_metadata {
/**
* @brief Node labels associated with the device
* @see device_get_dt_nodelabels()
*/
const struct device_dt_nodelabels *nl;
};
/**
* @brief Get a @ref device reference from a devicetree node label.
*
* If:
*
* 1. a device was defined from a devicetree node, for example
* with DEVICE_DT_DEFINE() or another similar macro, and
* 2. that devicetree node has @p nodelabel as one of its node labels, and
* 3. the device initialized successfully at boot time,
*
* then this function returns a pointer to the device. Otherwise, it
* returns NULL.
*
* @param nodelabel a devicetree node label
* @return a device reference for a device created from a node with that
* node label, or NULL if either no such device exists or the device
* failed to initialize
*/
__syscall const struct device *device_get_by_dt_nodelabel(const char *nodelabel);
/**
* @brief Get the devicetree node labels associated with a device
* @param dev device whose metadata to look up
* @return information about the devicetree node labels or NULL if not available
*/
static inline const struct device_dt_nodelabels *
device_get_dt_nodelabels(const struct device *dev)
{
if (dev->dt_meta == NULL) {
return NULL;
}
return dev->dt_meta->nl;
}
/**
* @brief Maximum devicetree node label length.
*
* The maximum length is set so that device_get_by_dt_nodelabel() can
* be used from userspace.
*/
#define Z_DEVICE_MAX_NODELABEL_LEN Z_DEVICE_MAX_NAME_LEN
/**
* @brief Name of the identifier for a device's DT metadata structure
* @param dev_id device identifier
*/
#define Z_DEVICE_DT_METADATA_NAME_GET(dev_id) UTIL_CAT(__dev_dt_meta_, dev_id)
/**
* @brief Name of the identifier for the array of node label strings
* saved for a device.
*/
#define Z_DEVICE_DT_NODELABELS_NAME_GET(dev_id) UTIL_CAT(__dev_dt_nodelabels_, dev_id)
/**
* @brief Initialize an entry in the device DT node label lookup table
*
* Allocates and initializes a struct device_dt_metadata in the
* appropriate iterable section for use finding devices.
*/
#define Z_DEVICE_DT_METADATA_DEFINE(node_id, dev_id) \
static const struct device_dt_nodelabels \
Z_DEVICE_DT_NODELABELS_NAME_GET(dev_id) = { \
.num_nodelabels = DT_NUM_NODELABELS(node_id), \
.nodelabels = DT_NODELABEL_STRING_ARRAY(node_id), \
}; \
\
static const struct device_dt_metadata \
Z_DEVICE_DT_METADATA_NAME_GET(dev_id) = { \
.nl = &Z_DEVICE_DT_NODELABELS_NAME_GET(dev_id), \
};
#endif /* CONFIG_DEVICE_DT_METADATA */
/**
* @brief Init sub-priority of the device
*
* The sub-priority is defined by the devicetree ordinal, which ensures that
* multiple drivers running at the same priority level run in an order that
* respects the devicetree dependencies.
*/
#define Z_DEVICE_INIT_SUB_PRIO(node_id) \
COND_CODE_1(DT_NODE_EXISTS(node_id), \
(DT_DEP_ORD_STR_SORTABLE(node_id)), (0))
/**
* @brief Maximum device name length.
*
* The maximum length is set so that device_get_binding() can be used from
* userspace.
*/
#define Z_DEVICE_MAX_NAME_LEN 48U
/**
* @brief Compile time check for device name length
*
* @param name Device name.
*/
#define Z_DEVICE_NAME_CHECK(name) \
BUILD_ASSERT(sizeof(Z_STRINGIFY(name)) <= Z_DEVICE_MAX_NAME_LEN, \
Z_STRINGIFY(name) " too long")
/**
* @brief Initializer for @ref device.
*
* @param name_ Name of the device.
* @param pm_ Reference to @ref pm_device_base (optional).
* @param data_ Reference to device data.
* @param config_ Reference to device config.
* @param api_ Reference to device API ops.
* @param state_ Reference to device state.
* @param deps_ Reference to device dependencies.
* @param node_id_ Devicetree node identifier
* @param dev_id_ Device identifier token, as passed to Z_DEVICE_BASE_DEFINE
*/
#define Z_DEVICE_INIT(name_, pm_, data_, config_, api_, state_, deps_, node_id_, \
dev_id_) \
{ \
.name = name_, \
.config = (config_), \
.api = (api_), \
.state = (state_), \
.data = (data_), \
IF_ENABLED(CONFIG_DEVICE_DEPS, (.deps = (deps_),)) /**/ \
IF_ENABLED(CONFIG_PM_DEVICE, Z_DEVICE_INIT_PM_BASE(pm_)) /**/ \
IF_ENABLED(CONFIG_DEVICE_DT_METADATA, \
(IF_ENABLED(DT_NODE_EXISTS(node_id_), \
(.dt_meta = &Z_DEVICE_DT_METADATA_NAME_GET( \
dev_id_),)))) \
}
/*
* Anonymous unions require C11. Some pre-C11 gcc versions have early support for anonymous
* unions but they require these braces when combined with C99 designated initializers. For
* more details see https://docs.zephyrproject.org/latest/develop/languages/cpp/
*/
#if defined(__STDC_VERSION__) && (__STDC_VERSION__) < 201100
# define Z_DEVICE_INIT_PM_BASE(pm_) ({ .pm_base = (pm_),},)
#else
# define Z_DEVICE_INIT_PM_BASE(pm_) (.pm_base = (pm_),)
#endif
/**
* @brief Device section name (used for sorting purposes).
*
* @param level Initialization level
* @param prio Initialization priority
*/
#define Z_DEVICE_SECTION_NAME(level, prio) \
_CONCAT(INIT_LEVEL_ORD(level), _##prio)
/**
* @brief Define a @ref device
*
* @param node_id Devicetree node id for the device (DT_INVALID_NODE if a
* software device).
* @param dev_id Device identifier (used to name the defined @ref device).
* @param name Name of the device.
* @param pm Reference to @ref pm_device_base associated with the device.
* (optional).
* @param data Reference to device data.
* @param config Reference to device config.
* @param level Initialization level.
* @param prio Initialization priority.
* @param api Reference to device API.
* @param ... Optional dependencies, manually specified.
*/
#define Z_DEVICE_BASE_DEFINE(node_id, dev_id, name, pm, data, config, level, prio, api, state, \
deps) \
COND_CODE_1(DT_NODE_EXISTS(node_id), (), (static)) \
COND_CODE_1(Z_DEVICE_IS_MUTABLE(node_id), (), (const)) \
STRUCT_SECTION_ITERABLE_NAMED_ALTERNATE( \
device, COND_CODE_1(Z_DEVICE_IS_MUTABLE(node_id), (device_mutable), (device)), \
Z_DEVICE_SECTION_NAME(level, prio), DEVICE_NAME_GET(dev_id)) = \
Z_DEVICE_INIT(name, pm, data, config, api, state, deps, node_id, dev_id)
/**
* @brief Issue an error if the given init level is not supported.
*
* @param level Init level
*/
#define Z_DEVICE_CHECK_INIT_LEVEL(level) \
COND_CODE_1(Z_INIT_PRE_KERNEL_1_##level, (), \
(COND_CODE_1(Z_INIT_PRE_KERNEL_2_##level, (), \
(COND_CODE_1(Z_INIT_POST_KERNEL_##level, (), \
(ZERO_OR_COMPILE_ERROR(0)))))))
/**
* @brief Define the init entry for a device.
*
* @param node_id Devicetree node id for the device (DT_INVALID_NODE if a
* software device).
* @param dev_id Device identifier.
* @param init_fn_ Device init function.
* @param level Initialization level.
* @param prio Initialization priority.
*/
#define Z_DEVICE_INIT_ENTRY_DEFINE(node_id, dev_id, init_fn_, level, prio) \
Z_DEVICE_CHECK_INIT_LEVEL(level) \
\
static const Z_DECL_ALIGN(struct init_entry) __used __noasan Z_INIT_ENTRY_SECTION( \
level, prio, Z_DEVICE_INIT_SUB_PRIO(node_id)) \
Z_INIT_ENTRY_NAME(DEVICE_NAME_GET(dev_id)) = { \
.init_fn = {COND_CODE_1(Z_DEVICE_IS_MUTABLE(node_id), (.dev_rw), (.dev)) = \
(init_fn_)}, \
Z_DEVICE_INIT_ENTRY_DEV(node_id, dev_id), \
}
#define Z_DEFER_DEVICE_INIT_ENTRY_DEFINE(node_id, dev_id, init_fn_) \
static const Z_DECL_ALIGN(struct init_entry) __used __noasan \
__attribute__((__section__(".z_deferred_init"))) \
Z_INIT_ENTRY_NAME(DEVICE_NAME_GET(dev_id)) = { \
.init_fn = {COND_CODE_1(Z_DEVICE_IS_MUTABLE(node_id), (.dev_rw), (.dev)) = \
(init_fn_)}, \
Z_DEVICE_INIT_ENTRY_DEV(node_id, dev_id), \
}
/*
* Anonymous unions require C11. Some pre-C11 gcc versions have early support for anonymous
* unions but they require these braces when combined with C99 designated initializers. For
* more details see https://docs.zephyrproject.org/latest/develop/languages/cpp/
*/
#if defined(__STDC_VERSION__) && (__STDC_VERSION__) < 201100
# define Z_DEVICE_INIT_ENTRY_DEV(node_id, dev_id) { Z_DEV_ENTRY_DEV(node_id, dev_id) }
#else
# define Z_DEVICE_INIT_ENTRY_DEV(node_id, dev_id) Z_DEV_ENTRY_DEV(node_id, dev_id)
#endif
#define Z_DEV_ENTRY_DEV(node_id, dev_id) \
COND_CODE_1(Z_DEVICE_IS_MUTABLE(node_id), (.dev_rw), (.dev)) = &DEVICE_NAME_GET(dev_id)
/**
* @brief Define a @ref device and all other required objects.
*
* This is the common macro used to define @ref device objects. It can be used
* to define both Devicetree and software devices.
*
* @param node_id Devicetree node id for the device (DT_INVALID_NODE if a
* software device).
* @param dev_id Device identifier (used to name the defined @ref device).
* @param name Name of the device.
* @param init_fn Device init function.
* @param pm Reference to @ref pm_device_base associated with the device.
* (optional).
* @param data Reference to device data.
* @param config Reference to device config.
* @param level Initialization level.
* @param prio Initialization priority.
* @param api Reference to device API.
* @param state Reference to device state.
* @param ... Optional dependencies, manually specified.
*/
#define Z_DEVICE_DEFINE(node_id, dev_id, name, init_fn, pm, data, config, \
level, prio, api, state, ...) \
Z_DEVICE_NAME_CHECK(name); \
\
IF_ENABLED(CONFIG_DEVICE_DEPS, \
(Z_DEVICE_DEPS_DEFINE(node_id, dev_id, __VA_ARGS__);)) \
\
IF_ENABLED(CONFIG_DEVICE_DT_METADATA, \
(IF_ENABLED(DT_NODE_EXISTS(node_id), \
(Z_DEVICE_DT_METADATA_DEFINE(node_id, dev_id);))))\
\
Z_DEVICE_BASE_DEFINE(node_id, dev_id, name, pm, data, config, level, \
prio, api, state, Z_DEVICE_DEPS_NAME(dev_id)); \
COND_CODE_1(DEVICE_DT_DEFER(node_id), \
(Z_DEFER_DEVICE_INIT_ENTRY_DEFINE(node_id, dev_id, \
init_fn)), \
(Z_DEVICE_INIT_ENTRY_DEFINE(node_id, dev_id, init_fn, \
level, prio)));
/**
* @brief Declare a device for each status "okay" devicetree node.
*
* @note Disabled nodes should not result in devices, so not predeclaring these
* keeps drivers honest.
*
* This is only "maybe" a device because some nodes have status "okay", but
* don't have a corresponding @ref device allocated. There's no way to figure
* that out until after we've built the zephyr image, though.
*/
#define Z_MAYBE_DEVICE_DECLARE_INTERNAL(node_id) \
extern COND_CODE_1(Z_DEVICE_IS_MUTABLE(node_id), (), \
(const)) struct device DEVICE_DT_NAME_GET(node_id);
DT_FOREACH_STATUS_OKAY_NODE(Z_MAYBE_DEVICE_DECLARE_INTERNAL)
/** @endcond */
#ifdef __cplusplus
}
#endif
#include <zephyr/syscalls/device.h>
#endif /* ZEPHYR_INCLUDE_DEVICE_H_ */