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This makes it easier to automatically generate parts of the manager documentation in the future. Update #3993.
422 lines
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ReStructuredText
422 lines
11 KiB
ReStructuredText
.. SPDX-License-Identifier: CC-BY-SA-4.0
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.. Copyright (C) 1988, 2008 On-Line Applications Research Corporation (OAR)
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Directives
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==========
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This section details the I/O manager's directives. A subsection is dedicated
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to each of this manager's directives and describes the calling sequence,
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related constants, usage, and status codes.
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.. raw:: latex
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\clearpage
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.. index:: register a device driver
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.. index:: rtems_io_register_driver
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.. _rtems_io_register_driver:
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IO_REGISTER_DRIVER - Register a device driver
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---------------------------------------------
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CALLING SEQUENCE:
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.. code-block:: c
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rtems_status_code rtems_io_register_driver(
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rtems_device_major_number major,
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rtems_driver_address_table *driver_table,
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rtems_device_major_number *registered_major
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);
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DIRECTIVE STATUS CODES:
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.. list-table::
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:class: rtems-table
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* - ``RTEMS_SUCCESSFUL``
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- successfully registered
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* - ``RTEMS_INVALID_ADDRESS``
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- invalid registered major pointer
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* - ``RTEMS_INVALID_ADDRESS``
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- invalid driver table
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* - ``RTEMS_INVALID_NUMBER``
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- invalid major device number
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* - ``RTEMS_TOO_MANY``
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- no available major device table slot
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* - ``RTEMS_RESOURCE_IN_USE``
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- major device number entry in use
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DESCRIPTION:
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This directive attempts to add a new device driver to the Device Driver
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Table. The user can specify a specific major device number via the
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directive's ``major`` parameter, or let the registration routine find the
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next available major device number by specifing a major number of
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``0``. The selected major device number is returned via the
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``registered_major`` directive parameter. The directive automatically
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allocation major device numbers from the highest value down.
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This directive automatically invokes the ``IO_INITIALIZE`` directive if the
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driver address table has an initialization and open entry.
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The directive returns ``RTEMS_TOO_MANY`` if Device Driver Table is full,
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and ``RTEMS_RESOURCE_IN_USE`` if a specific major device number is
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requested and it is already in use.
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NOTES:
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The Device Driver Table size is specified in the Configuration Table
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condiguration. This needs to be set to maximum size the application
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requires.
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.. raw:: latex
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\clearpage
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.. index:: unregister a device driver
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.. index:: rtems_io_unregister_driver
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.. _rtems_io_unregister_driver:
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IO_UNREGISTER_DRIVER - Unregister a device driver
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-------------------------------------------------
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CALLING SEQUENCE:
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.. code-block:: c
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rtems_status_code rtems_io_unregister_driver(
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rtems_device_major_number major
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);
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DIRECTIVE STATUS CODES:
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.. list-table::
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:class: rtems-table
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* - ``RTEMS_SUCCESSFUL``
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- successfully registered
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* - ``RTEMS_INVALID_NUMBER``
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- invalid major device number
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DESCRIPTION:
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This directive removes a device driver from the Device Driver Table.
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NOTES:
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Currently no specific checks are made and the driver is not closed.
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.. raw:: latex
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\clearpage
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.. index:: initialize a device driver
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.. index:: rtems_io_initialize
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.. _rtems_io_initialize:
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IO_INITIALIZE - Initialize a device driver
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------------------------------------------
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CALLING SEQUENCE:
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.. code-block:: c
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rtems_status_code rtems_io_initialize(
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rtems_device_major_number major,
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rtems_device_minor_number minor,
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void *argument
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);
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DIRECTIVE STATUS CODES:
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.. list-table::
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:class: rtems-table
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* - ``RTEMS_SUCCESSFUL``
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- successfully initialized
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* - ``RTEMS_INVALID_NUMBER``
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- invalid major device number
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DESCRIPTION:
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This directive calls the device driver initialization routine specified in
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the Device Driver Table for this major number. This directive is
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automatically invoked for each device driver when multitasking is initiated
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via the initialize_executive directive.
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A device driver initialization module is responsible for initializing all
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hardware and data structures associated with a device. If necessary, it can
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allocate memory to be used during other operations.
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NOTES:
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This directive may or may not cause the calling task to be preempted. This
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is dependent on the device driver being initialized.
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.. raw:: latex
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\clearpage
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.. index:: register device
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.. index:: rtems_io_register_name
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.. _rtems_io_register_name:
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IO_REGISTER_NAME - Register a device
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------------------------------------
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CALLING SEQUENCE:
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.. code-block:: c
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rtems_status_code rtems_io_register_name(
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const char *name,
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rtems_device_major_number major,
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rtems_device_minor_number minor
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);
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DIRECTIVE STATUS CODES:
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.. list-table::
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:class: rtems-table
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* - ``RTEMS_SUCCESSFUL``
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- successfully initialized
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* - ``RTEMS_TOO_MANY``
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- too many devices registered
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DESCRIPTION:
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This directive associates name with the specified major/minor number pair.
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NOTES:
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This directive will not cause the calling task to be preempted.
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.. raw:: latex
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\clearpage
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.. index:: lookup device major and minor number
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.. index:: rtems_io_lookup_name
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.. _rtems_io_lookup_name:
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IO_LOOKUP_NAME - Lookup a device
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--------------------------------
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CALLING SEQUENCE:
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.. code-block:: c
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rtems_status_code rtems_io_lookup_name(
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const char *name,
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rtems_driver_name_t *device_info
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);
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DIRECTIVE STATUS CODES:
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.. list-table::
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:class: rtems-table
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* - ``RTEMS_SUCCESSFUL``
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- successfully initialized
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* - ``RTEMS_UNSATISFIED``
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- name not registered
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DESCRIPTION:
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This directive returns the major/minor number pair associated with the
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given device name in ``device_info``.
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NOTES:
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This directive will not cause the calling task to be preempted.
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.. raw:: latex
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\clearpage
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.. index:: open a devive
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.. index:: rtems_io_open
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.. _rtems_io_open:
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IO_OPEN - Open a device
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-----------------------
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CALLING SEQUENCE:
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.. code-block:: c
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rtems_status_code rtems_io_open(
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rtems_device_major_number major,
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rtems_device_minor_number minor,
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void *argument
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);
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DIRECTIVE STATUS CODES:
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.. list-table::
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:class: rtems-table
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* - ``RTEMS_SUCCESSFUL``
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- successfully initialized
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* - ``RTEMS_INVALID_NUMBER``
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- invalid major device number
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DESCRIPTION:
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This directive calls the device driver open routine specified in the Device
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Driver Table for this major number. The open entry point is commonly used
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by device drivers to provide exclusive access to a device.
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NOTES:
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This directive may or may not cause the calling task to be preempted. This
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is dependent on the device driver being invoked.
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.. raw:: latex
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\clearpage
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.. index:: close a device
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.. index:: rtems_io_close
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.. _rtems_io_close:
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IO_CLOSE - Close a device
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-------------------------
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CALLING SEQUENCE:
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.. code-block:: c
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rtems_status_code rtems_io_close(
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rtems_device_major_number major,
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rtems_device_minor_number minor,
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void *argument
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);
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DIRECTIVE STATUS CODES:
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.. list-table::
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:class: rtems-table
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* - ``RTEMS_SUCCESSFUL``
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- successfully initialized
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* - ``RTEMS_INVALID_NUMBER``
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- invalid major device number
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DESCRIPTION:
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This directive calls the device driver close routine specified in the
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Device Driver Table for this major number. The close entry point is
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commonly used by device drivers to relinquish exclusive access to a device.
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NOTES:
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This directive may or may not cause the calling task to be preempted. This
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is dependent on the device driver being invoked.
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.. raw:: latex
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\clearpage
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.. index:: read from a device
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.. index:: rtems_io_read
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.. _rtems_io_read:
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IO_READ - Read from a device
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----------------------------
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CALLING SEQUENCE:
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.. code-block:: c
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rtems_status_code rtems_io_read(
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rtems_device_major_number major,
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rtems_device_minor_number minor,
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void *argument
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);
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DIRECTIVE STATUS CODES:
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.. list-table::
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:class: rtems-table
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* - ``RTEMS_SUCCESSFUL``
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- successfully initialized
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* - ``RTEMS_INVALID_NUMBER``
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- invalid major device number
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DESCRIPTION:
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This directive calls the device driver read routine specified in the Device
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Driver Table for this major number. Read operations typically require a
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buffer address as part of the argument parameter block. The contents of
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this buffer will be replaced with data from the device.
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NOTES:
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This directive may or may not cause the calling task to be preempted. This
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is dependent on the device driver being invoked.
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.. raw:: latex
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\clearpage
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.. index:: write to a device
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.. index:: rtems_io_write
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.. _rtems_io_write:
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IO_WRITE - Write to a device
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----------------------------
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CALLING SEQUENCE:
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.. code-block:: c
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rtems_status_code rtems_io_write(
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rtems_device_major_number major,
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rtems_device_minor_number minor,
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void *argument
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);
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DIRECTIVE STATUS CODES:
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.. list-table::
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:class: rtems-table
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* - ``RTEMS_SUCCESSFUL``
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- successfully initialized
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* - ``RTEMS_INVALID_NUMBER``
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- invalid major device number
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DESCRIPTION:
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This directive calls the device driver write routine specified in the
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Device Driver Table for this major number. Write operations typically
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require a buffer address as part of the argument parameter block. The
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contents of this buffer will be sent to the device.
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NOTES:
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This directive may or may not cause the calling task to be preempted. This
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is dependent on the device driver being invoked.
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.. raw:: latex
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\clearpage
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.. index:: special device services
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.. index:: IO Control
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.. index:: rtems_io_control
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.. _rtems_io_control:
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IO_CONTROL - Special device services
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------------------------------------
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CALLING SEQUENCE:
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.. code-block:: c
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rtems_status_code rtems_io_control(
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rtems_device_major_number major,
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rtems_device_minor_number minor,
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void *argument
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);
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DIRECTIVE STATUS CODES:
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.. list-table::
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:class: rtems-table
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* - ``RTEMS_SUCCESSFUL``
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- successfully initialized
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* - ``RTEMS_INVALID_NUMBER``
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- invalid major device number
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DESCRIPTION:
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This directive calls the device driver I/O control routine specified in the
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Device Driver Table for this major number. The exact functionality of the
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driver entry called by this directive is driver dependent. It should not
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be assumed that the control entries of two device drivers are compatible.
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For example, an RS-232 driver I/O control operation may change the baud
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rate of a serial line, while an I/O control operation for a floppy disk
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driver may cause a seek operation.
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NOTES:
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This directive may or may not cause the calling task to be preempted. This
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is dependent on the device driver being invoked.
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