On Mon, Jun 01, 2020 at 06:06:43PM +0300, Maxim Uvarov wrote:
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 Reviewed-by: Sumit Garg sumit.garg@linaro.org
Why do you mean by duplicate sysfs entries?
Documentation/ABI/testing/sysfs-bus-optee-devices | 8 ++++++++ MAINTAINERS | 1 + drivers/tee/optee/device.c | 6 +++--- 3 files changed, 12 insertions(+), 3 deletions(-) create mode 100644 Documentation/ABI/testing/sysfs-bus-optee-devices
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..6717afef2de3 100644 --- a/MAINTAINERS +++ b/MAINTAINERS @@ -12516,6 +12516,7 @@ 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/ OP-TEE RANDOM NUMBER GENERATOR (RNG) DRIVER diff --git a/drivers/tee/optee/device.c b/drivers/tee/optee/device.c index e3a148521ec1..ed3d1ddfa52b 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);
This code is and already was broken. If dev_set_name() returns -ENOMEM, the name will be a null pointer.
Also, I don't get how you can just swap the name without potentially breaking the backwards compatiblity towards the user space.
/Jarkko