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ce2e4ebdf1
This adds the DEVICE_AND_API_INIT() macro to take in a parameter to assign to device->driver_api. This eliminates the need to assign to driver_api during runtime device initialization. This provides an alternative way to declare devices. This should save a few bytes in ROM for those devices that will never fail initialization (in other words, never need to manipulate driver_api pointer at all). Also clean up the documentation a bit to remove duplicated block of information. Change-Id: I6abed1abe75db2e8babfcf1ecf590491132a5543 Signed-off-by: Daniel Leung <daniel.leung@intel.com>
44 lines
1.3 KiB
ReStructuredText
44 lines
1.3 KiB
ReStructuredText
.. _device_drivers:
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Device Drivers and Device Model
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###############################
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Introduction
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************
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The Zephyr device model provides a consistent device model for configuring the
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drivers that are part of the platform/system. The device model is responsible
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for initializing all the drivers configured into the system.
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Each type of driver (UART, SPI, I2C) is supported by a generic type API.
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In this model the driver fills in the pointer to the structure containing the
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function pointers to its API functions during driver initialization. These
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structures are placed into the RAM section in initialization level order.
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.. include:: synchronous_call.rst
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Driver APIs
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***********
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The following APIs for device drivers are provided by :file:`device.h`. The APIs
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are intended for use in device drivers only and should not be used in
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applications.
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:c:func:`DEVICE_INIT()`
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create device object and set it up for boot time initialization.
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:c:func:`DEVICE_AND_API_INIT()`
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Create device object and set it up for boot time initialization.
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This also takes a pointer to driver API struct for link time
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pointer assignment.
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:c:func:`DEVICE_NAME_GET()`
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Expands to the full name of a global device object.
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:c:func:`DEVICE_GET()`
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Obtain a pointer to a device object by name.
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:c:func:`DEVICE_DECLARE()`
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Declare a device object.
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