[PATCHv5 2/3] optee: use uuid for sysfs driver entry

From: Maxim Uvarov <maxim.uvarov@linaro.org>
To: linux-kernel@vger.kernel.org, tee-dev@lists.linaro.org
Cc: peterhuewe@gmx.de, jarkko.sakkinen@linux.intel.com, jgg@ziepe.ca,
	gregkh@linuxfoundation.org, jens.wiklander@linaro.org,
	linux-integrity@vger.kernel.org, arnd@linaro.org,
	sumit.garg@linaro.org, Maxim Uvarov <maxim.uvarov@linaro.org>
Subject: [PATCHv5 2/3] optee: use uuid for sysfs driver entry
Date: Fri, 29 May 2020 11:27:00 +0300	[thread overview]
Message-ID: <20200529082701.13457-3-maxim.uvarov@linaro.org> (raw)
In-Reply-To: <20200529082701.13457-1-maxim.uvarov@linaro.org>

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>

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

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. Drivers
+		are 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/
 
+
 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

