On Fri, 29 May 2020 at 13:57, Maxim Uvarov maxim.uvarov@linaro.org wrote:
OP-TEE device names for sysfs need to be unique and it's better if they will mean something. UUID for name looks like good solution: /sys/bus/tee/devices/optee-ta-<uuid>
I think this description is a little vague here which fails to explain why we are doing this. How about:
======= With the evolving use-cases for TEE bus, now it's required to support multi-stage enumeration process. But using a simple index doesn't suffice this requirement and instead leads to duplicate sysfs entries. So instead switch to use more informative device UUID for sysfs entry like:
/sys/bus/tee/devices/optee-ta-<uuid> ========
Signed-off-by: Maxim Uvarov maxim.uvarov@linaro.org
Documentation/ABI/testing/sysfs-bus-optee-devices | 8 ++++++++ MAINTAINERS | 2 ++ drivers/tee/optee/device.c | 6 +++--- 3 files changed, 13 insertions(+), 3 deletions(-) create mode 100644 Documentation/ABI/testing/sysfs-bus-optee-devices
I think this patch belongs as patch #1 in this series given the dependency.
diff --git a/Documentation/ABI/testing/sysfs-bus-optee-devices b/Documentation/ABI/testing/sysfs-bus-optee-devices new file mode 100644 index 000000000000..0ae04ae5374a --- /dev/null +++ b/Documentation/ABI/testing/sysfs-bus-optee-devices @@ -0,0 +1,8 @@ +What: /sys/bus/tee/devices/optee-ta-<uuid>/ +Date: May 2020 +KernelVersion 5.7 +Contact: tee-dev@lists.linaro.org +Description:
OP-TEE bus provides reference to registered drivers under this directory. The <uuid>matches Trusted Application (TA) driver and corresponding TA in secure OS. Driversare free to create needed API under optee-ta-<uuid> directory.diff --git a/MAINTAINERS b/MAINTAINERS index ecc0749810b0..52717ede29fc 100644 --- a/MAINTAINERS +++ b/MAINTAINERS @@ -12516,8 +12516,10 @@ OP-TEE DRIVER M: Jens Wiklander jens.wiklander@linaro.org L: tee-dev@lists.linaro.org S: Maintained +F: Documentation/ABI/testing/sysfs-bus-optee-devices F: drivers/tee/optee/
Unnecessary blank line.
-Sumit
OP-TEE RANDOM NUMBER GENERATOR (RNG) DRIVER M: Sumit Garg sumit.garg@linaro.org L: tee-dev@lists.linaro.org diff --git a/drivers/tee/optee/device.c b/drivers/tee/optee/device.c index d4931dad07aa..2eb1c0283aec 100644 --- a/drivers/tee/optee/device.c +++ b/drivers/tee/optee/device.c @@ -65,7 +65,7 @@ static int get_devices(struct tee_context *ctx, u32 session, return 0; }
-static int optee_register_device(const uuid_t *device_uuid, u32 device_id) +static int optee_register_device(const uuid_t *device_uuid) { struct tee_client_device *optee_device = NULL; int rc; @@ -75,7 +75,7 @@ static int optee_register_device(const uuid_t *device_uuid, u32 device_id) return -ENOMEM;
optee_device->dev.bus = &tee_bus_type;
dev_set_name(&optee_device->dev, "optee-clnt%u", device_id);
dev_set_name(&optee_device->dev, "optee-ta-%pUl", device_uuid); uuid_copy(&optee_device->id.uuid, device_uuid); rc = device_register(&optee_device->dev);@@ -144,7 +144,7 @@ static int __optee_enumerate_devices(u32 func) num_devices = shm_size / sizeof(uuid_t);
for (idx = 0; idx < num_devices; idx++) {
rc = optee_register_device(&device_uuid[idx], idx);
rc = optee_register_device(&device_uuid[idx]); if (rc) goto out_shm; }-- 2.17.1