zephyr/include/device.h

490 lines
15 KiB
C

/*
* Copyright (c) 2015 Intel Corporation.
*
* Licensed under the Apache License, Version 2.0 (the "License");
* you may not use this file except in compliance with the License.
* You may obtain a copy of the License at
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS,
* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
* See the License for the specific language governing permissions and
* limitations under the License.
*/
#ifndef _DEVICE_H_
#define _DEVICE_H_
/**
* @brief Device Driver APIs
* @defgroup io_interfaces Device Driver APIs
* @{
* @}
*/
/**
* @brief Device Model APIs
* @defgroup device_model Device Model APIs
* @{
*/
#ifdef __cplusplus
extern "C" {
#endif
/**
* @def DEVICE_INIT
*
* @brief Create device object and set it up for boot time initialization.
*
* @details This macro defines a device object that is automatically
* configured by the kernel during system initialization.
*
* @param dev_name Device name.
*
* @param drv_name The name this instance of the driver exposes to
* the system.
*
* @param init_fn Address to the init function of the driver.
*
* @param data Pointer to the device's configuration data.
*
* @param cfg_info The address to the structure containing the
* configuration information for this instance of the driver.
*
* @param level The initialization level at which configuration occurs.
* Must be one of the following symbols, which are listed in the order
* they are performed by the kernel:
* \n
* \li PRIMARY: Used for devices that have no dependencies, such as those
* that rely solely on hardware present in the processor/SOC. These devices
* cannot use any kernel services during configuration, since they are not
* yet available.
* \n
* \li SECONDARY: Used for devices that rely on the initialization of devices
* initialized as part of the PRIMARY level. These devices cannot use any
* kernel services during configuration, since they are not yet available.
* \n
* \li NANOKERNEL: Used for devices that require nanokernel services during
* configuration.
* \n
* \li MICROKERNEL: Used for devices that require microkernel services during
* configuration.
* \n
* \li APPLICATION: Used for application components (i.e. non-kernel components)
* that need automatic configuration. These devices can use all services
* provided by the kernel during configuration.
*
* @param prio The initialization priority of the device, relative to
* other devices of the same initialization level. Specified as an integer
* value in the range 0 to 99; lower values indicate earlier initialization.
* Must be a decimal integer literal without leading zeroes or sign (e.g. 32),
* or an equivalent symbolic name (e.g. \#define MY_INIT_PRIO 32); symbolic
* expressions are *not* permitted
* (e.g. CONFIG_KERNEL_INIT_PRIORITY_DEFAULT + 5).
*/
/**
* @def DEVICE_AND_API_INIT
*
* @brief Create device object and set it up for boot time initialization,
* with the option to set driver_api.
*
* @details This macro defines a device object that is automatically
* configured by the kernel during system initialization. The driver_api
* is also be set here, eliminating the need to do that during initialization.
*
* \see DEVICE_INIT() for description on other parameters.
*
* @param api Provides an initial pointer to the API function struct
* used by the driver. Can be NULL.
*/
#ifndef CONFIG_DEVICE_POWER_MANAGEMENT
#define DEVICE_AND_API_INIT(dev_name, drv_name, init_fn, data, cfg_info, \
level, prio, api) \
\
static struct device_config __config_##dev_name __used \
__attribute__((__section__(".devconfig.init"))) = { \
.name = drv_name, .init = (init_fn), \
.config_info = (cfg_info) \
}; \
\
static struct device (__device_##dev_name) __used \
__attribute__((__section__(".init_" #level STRINGIFY(prio)))) = { \
.config = &(__config_##dev_name), \
.driver_api = api, \
.driver_data = data \
}
#define DEVICE_INIT(dev_name, drv_name, init_fn, data, cfg_info, level, prio) \
DEVICE_AND_API_INIT(dev_name, drv_name, init_fn, data, cfg_info, \
level, prio, NULL)
#else
/**
* @def DEVICE_AND_API_INIT_PM
*
* @brief Create device object and set it up for boot time initialization,
* with the options to set driver_api and device_pm_ops.
*
* @details This macro defines a device object that is automatically
* configured by the kernel during system initialization. This driver_api
* and device_pm_ops are also be set here.
*
* @param device_pm_ops Address to the device_pm_ops structure of the driver.
*
* \see DEVICE_AND_API_INIT() for description on other parameters.
*/
#define DEVICE_AND_API_INIT_PM(dev_name, drv_name, init_fn, device_pm_ops, \
data, cfg_info, level, prio, api) \
\
static struct device_config __config_##dev_name __used \
__attribute__((__section__(".devconfig.init"))) = { \
.name = drv_name, .init = (init_fn), \
.dev_pm_ops = (device_pm_ops), \
.config_info = (cfg_info) \
}; \
\
static struct device (__device_##dev_name) __used \
__attribute__((__section__(".init_" #level STRINGIFY(prio)))) = { \
.config = &(__config_##dev_name), \
.driver_api = api, \
.driver_data = data \
}
/**
* @def DEVICE_INIT_PM
*
* @brief Create device object and set it up for boot time initialization,
* with the options to device_pm_ops.
*
* @details This macro defines a device object that is automatically
* configured by the kernel during system initialization. This device_pm_ops
* is also be set here.
*
* @param device_pm_ops Address to the device_pm_ops structure of the driver.
*
* \see DEVICE_INIT() for description on other parameters.
*/
#define DEVICE_INIT_PM(dev_name, drv_name, init_fn, device_pm_ops, \
data, cfg_info, level, prio) \
DEVICE_AND_API_INIT_PM(dev_name, drv_name, init_fn, device_pm_ops, \
data, cfg_info, level, prio, NULL)
/*
* Create a default device_pm_ops for devices that do not call the
* DEVICE_INIT_PM macro so that caller of hook functions
* need not check dev_pm_ops != NULL.
*/
extern struct device_pm_ops device_pm_ops_nop;
#define DEVICE_AND_API_INIT(dev_name, drv_name, init_fn, data, cfg_info, \
level, prio, api) \
DEVICE_AND_API_INIT_PM(dev_name, drv_name, init_fn, \
&device_pm_ops_nop, data, cfg_info, \
level, prio, api)
#define DEVICE_INIT(dev_name, drv_name, init_fn, data, cfg_info, level, prio) \
DEVICE_AND_API_INIT(dev_name, drv_name, init_fn, data, cfg_info, \
level, prio, NULL)
#endif
/**
* @def DEVICE_NAME_GET
*
* @brief Expands to the full name of a global device object
*
* @details Return the full name of a device object symbol created by
* DEVICE_INIT(), using the dev_name provided to DEVICE_INIT().
*
* It is meant to be used for declaring extern symbols pointing on device
* objects before using the DEVICE_GET macro to get the device object.
*
* @param name The same as dev_name provided to DEVICE_INIT()
*
* @return The exanded name of the device object created by DEVICE_INIT()
*/
#define DEVICE_NAME_GET(name) (_CONCAT(__device_, name))
/**
* @def DEVICE_GET
*
* @brief Obtain a pointer to a device object by name
*
* @details Return the address of a device object created by
* DEVICE_INIT(), using the dev_name provided to DEVICE_INIT().
*
* @param name The same as dev_name provided to DEVICE_INIT()
*
* @return A pointer to the device object created by DEVICE_INIT()
*/
#define DEVICE_GET(name) (&DEVICE_NAME_GET(name))
/** @def DEVICE_DECLARE
*
* @brief Declare a 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_INIT(), or reference the device in another C file.
*
* 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_INIT() and use of DEVICE_GET()
* inside it creates a circular dependeny.
*
* @param name Device name
*/
#define DEVICE_DECLARE(name) extern struct device DEVICE_NAME_GET(name)
struct device;
#ifdef CONFIG_DEVICE_POWER_MANAGEMENT
/**
* @brief Device Power Management APIs
* @defgroup device_power_management_api Device Power Management APIs
* @ingroup power_management_api
* @{
*/
/**
* @brief Structure holding handlers for device PM operations
* @param suspend Pointer to the handler for suspend operations
* @param resume Pointer to the handler for resume operations
*/
struct device_pm_ops {
int (*suspend)(struct device *device, int pm_policy);
int (*resume)(struct device *device, int pm_policy);
};
/**
* @}
*/
#endif
/**
* @brief Static device information (In ROM) Per driver instance
* @param name name of the device
* @param init init function for the driver
* @param config_info address of driver instance config information
*/
struct device_config {
char *name;
int (*init)(struct device *device);
#ifdef CONFIG_DEVICE_POWER_MANAGEMENT
struct device_pm_ops *dev_pm_ops;
#endif
void *config_info;
};
/**
* @brief Runtime device structure (In memory) Per driver instance
* @param device_config Build time config information
* @param driver_api pointer to structure containing the API functions for
* the device type. This pointer is filled in by the driver at init time.
* @param driver_data river instance data. For driver use only
*/
struct device {
struct device_config *config;
void *driver_api;
void *driver_data;
};
void _sys_device_do_config_level(int level);
/**
* @brief Retrieve the device structure for a driver by name
*
* @details Device objects are created via the DEVICE_INIT() macro and
* placed in memory by the linker. If a driver needs to bind to another driver
* it can use this function to retrieve the device structure of the lower level
* driver by the name the driver exposes to the system.
*
* @param name device name to search for.
*
* @return pointer to device structure; NULL if not found or cannot be used.
*/
struct device* device_get_binding(char *name);
/**
* @brief Device Power Management APIs
* @defgroup device_power_management_api Device Power Management APIs
* @ingroup power_management_api
* @{
*/
/**
* @brief Indicate that the device is in the middle of a transaction
*
* Called by a device driver to indicate that it is in the middle of a
* transaction.
*
* @param busy_dev Pointer to device structure of the driver instance.
*/
void device_busy_set(struct device *busy_dev);
/**
* @brief Indicate that the device has completed its transaction
*
* Called by a device driver to indicate the end of a transaction.
*
* @param busy_dev Pointer to device structure of the driver instance.
*/
void device_busy_clear(struct device *busy_dev);
#ifdef CONFIG_DEVICE_POWER_MANAGEMENT
/*
* Device PM functions
*/
/**
* @brief No-op function to initialize unimplemented pm hooks
*
* This function should be used to initialize device pm hooks
* for which a device has no operation.
*
* @param unused_device Unused
* @param unused_policy Unused
*
* @retval 0 Always returns 0
*/
int device_pm_nop(struct device *unused_device, int unused_policy);
/**
* @brief Call the suspend function of a device
*
* Called by the Power Manager application to let the device do
* any policy based PM suspend operations.
*
* @param device Pointer to device structure of the driver instance.
* @param pm_policy PM policy for which this call is made.
*
* @retval 0 If successful.
* @retval Errno Negative errno code if failure.
*/
static inline int device_suspend(struct device *device, int pm_policy)
{
return device->config->dev_pm_ops->suspend(device, pm_policy);
}
/**
* @brief Call the resume function of a device
*
* Called by the Power Manager application to let the device do
* any policy based PM resume operations.
*
* @param device Pointer to device structure of the driver instance.
* @param pm_policy PM policy for which this call is made.
*
* @retval 0 If successful.
* @retval Errno Negative errno code if failure.
*/
static inline int device_resume(struct device *device, int pm_policy)
{
return device->config->dev_pm_ops->resume(device, pm_policy);
}
/**
* @brief Gets the device structure list array and device count
*
* Called by the Power Manager application to get the list of
* device structures associated with the devices in the system.
* The PM app would use this list to create its own sorted list
* based on the order it wishes to suspend or resume the devices.
*
* @param device_list Pointer to receive the device list array
* @param device_count Pointer to receive the device count
*/
void device_list_get(struct device **device_list, int *device_count);
/**
* @brief Check if any device is in the middle of a transaction
*
* Called by an application to see if any device is in the middle
* of a critical transaction that cannot be interrupted.
*
* @retval 0 if no device is busy
* @retval -EBUSY if any device is busy
*/
int device_any_busy_check(void);
/**
* @brief Check if a specific device is in the middle of a transaction
*
* Called by an application to see if a particular device is in the
* middle of a critical transaction that cannot be interrupted.
*
* @param chk_dev Pointer to device structure of the specific device driver
* the caller is interested in.
* @retval 0 if the device is not busy
* @retval -EBUSY if the device is busy
*/
int device_busy_check(struct device *chk_dev);
#endif
/**
* @}
*/
/**
* Synchronous calls API
*/
#include <stdbool.h>
#include <nanokernel.h>
#ifdef CONFIG_MICROKERNEL
#include <microkernel.h>
#endif
/**
* Specific type for synchronizing calls among the 2 possible contexts
*/
typedef struct {
/** Nanokernel semaphore used for fiber context */
struct nano_sem f_sem;
} device_sync_call_t;
/**
* @brief Initialize the context-dependent synchronization data
*
* @param sync A pointer to a valid device_sync_call_t
*/
static inline void device_sync_call_init(device_sync_call_t *sync)
{
nano_sem_init(&sync->f_sem);
}
/**
* @brief Wait for the isr to complete the synchronous call
* Note: It will simply wait on the internal semaphore.
*
* @param sync A pointer to a valid device_sync_call_t
*/
static inline void device_sync_call_wait(device_sync_call_t *sync)
{
nano_sem_take(&sync->f_sem, TICKS_UNLIMITED);
}
/**
* @brief Signal the waiter about synchronization completion
* Note: It will simply release the internal semaphore
*
* @param sync A pointer to a valid device_sync_call_t
*/
static inline void device_sync_call_complete(device_sync_call_t *sync)
{
nano_sem_give(&sync->f_sem);
}
#ifdef __cplusplus
}
#endif
/**
* @}
*/
#endif /* _DEVICE_H_ */