TEE (Trusted Execution Environment) driver API¶

Kernel provides a TEE bus infrastructure where a Trusted Application isrepresented as a device identified via Universally Unique Identifier (UUID) andclient drivers register a table of supported device UUIDs.

TEE bus infrastructure registers following APIs:

match():

iterates over the client driver UUID table to find a correspondingmatch for device UUID. If a match is found, then this particular device isprobed via corresponding probe API registered by the client driver. Thisprocess happens whenever a device or a client driver is registered with TEEbus.

uevent():

notifies user-space (udev) whenever a new device is registered onTEE bus for auto-loading of modularized client drivers.

TEE bus device enumeration is specific to underlying TEE implementation, so itis left open for TEE drivers to provide corresponding implementation.

Then TEE client driver can talk to a matched Trusted Application using APIslisted in include/linux/tee_drv.h.

static const struct tee_client_device_id client_id_table[] = {        {UUID_INIT(0xac6a4085, 0x0e82, 0x4c33,                   0xbf, 0x98, 0x8e, 0xb8, 0xe1, 0x18, 0xb6, 0xc2)},        {}};MODULE_DEVICE_TABLE(tee, client_id_table);static struct tee_client_driver client_driver = {        .id_table       = client_id_table,        .driver         = {                .name           = DRIVER_NAME,                .bus            = &tee_bus_type,                .probe          = client_probe,                .remove         = client_remove,        },};static int __init client_init(void){        return driver_register(&client_driver.driver);}static void __exit client_exit(void){        driver_unregister(&client_driver.driver);}module_init(client_init);module_exit(client_exit);