67 lines
2.0 KiB
ReStructuredText
67 lines
2.0 KiB
ReStructuredText
.. SPDX-License-Identifier: GPL-2.0
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===============================================
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TEE (Trusted Execution Environment) driver API
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===============================================
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Kernel provides a TEE bus infrastructure where a Trusted Application is
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represented as a device identified via Universally Unique Identifier (UUID) and
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client drivers register a table of supported device UUIDs.
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TEE bus infrastructure registers following APIs:
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match():
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iterates over the client driver UUID table to find a corresponding
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match for device UUID. If a match is found, then this particular device is
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probed via corresponding probe API registered by the client driver. This
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process happens whenever a device or a client driver is registered with TEE
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bus.
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uevent():
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notifies user-space (udev) whenever a new device is registered on
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TEE bus for auto-loading of modularized client drivers.
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TEE bus device enumeration is specific to underlying TEE implementation, so it
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is left open for TEE drivers to provide corresponding implementation.
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Then TEE client driver can talk to a matched Trusted Application using APIs
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listed in include/linux/tee_drv.h.
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TEE client driver example
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-------------------------
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Suppose a TEE client driver needs to communicate with a Trusted Application
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having UUID: ``ac6a4085-0e82-4c33-bf98-8eb8e118b6c2``, so driver registration
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snippet would look like::
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static const struct tee_client_device_id client_id_table[] = {
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{UUID_INIT(0xac6a4085, 0x0e82, 0x4c33,
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0xbf, 0x98, 0x8e, 0xb8, 0xe1, 0x18, 0xb6, 0xc2)},
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{}
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};
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MODULE_DEVICE_TABLE(tee, client_id_table);
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static struct tee_client_driver client_driver = {
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.id_table = client_id_table,
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.driver = {
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.name = DRIVER_NAME,
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.bus = &tee_bus_type,
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.probe = client_probe,
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.remove = client_remove,
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},
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};
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static int __init client_init(void)
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{
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return driver_register(&client_driver.driver);
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}
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static void __exit client_exit(void)
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{
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driver_unregister(&client_driver.driver);
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}
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module_init(client_init);
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module_exit(client_exit);
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