[PATCH v1 00/17] tee: Use bus callbacks instead of driver callbacks

[PATCH v1 00/17] tee: Use bus callbacks instead of driver callbacks

[Uwe Kleine-König]

Hello,

the objective of this series is to make tee driver stop using callbacks
in struct device_driver. These were superseded by bus methods in 2006
(commit 594c8281f905 ("[PATCH] Add bus_type probe, remove, shutdown
methods.")) but nobody cared to convert all subsystems accordingly.

Here the tee drivers are converted. The first commit is somewhat
unrelated, but simplifies the conversion (and the drivers). It
introduces driver registration helpers that care about setting the bus
and owner. (The latter is missing in all drivers, so by using these
helpers the drivers become more correct.)

The patches #4 - #17 depend on the first two, so if they should be
applied to their respective subsystem trees these must contain the first
two patches first.

Note that after patch #2 is applied, unconverted drivers provoke a
warning in driver_register(), so it would be good for the user
experience if the whole series goes in during a single merge window. So
I guess an immutable branch containing the frist three patches that can
be merged into the other subsystem trees would be sensible.

After all patches are applied, tee_bus_type can be made private to
drivers/tee as it's not used in other places any more.

Best regards
Uwe

Uwe Kleine-König (17):
  tee: Add some helpers to reduce boilerplate for tee client drivers
  tee: Add probe, remove and shutdown bus callbacks to tee_client_driver
  tee: Adapt documentation to cover recent additions
  hwrng: optee - Make use of module_tee_client_driver()
  hwrng: optee - Make use of tee bus methods
  rtc: optee: Migrate to use tee specific driver registration function
  rtc: optee: Make use of tee bus methods
  efi: stmm: Make use of module_tee_client_driver()
  efi: stmm: Make use of tee bus methods
  firmware: arm_scmi: optee: Make use of module_tee_client_driver()
  firmware: arm_scmi: Make use of tee bus methods
  firmware: tee_bnxt: Make use of module_tee_client_driver()
  firmware: tee_bnxt: Make use of tee bus methods
  KEYS: trusted: Migrate to use tee specific driver registration
    function
  KEYS: trusted: Make use of tee bus methods
  tpm/tpm_ftpm_tee: Make use of tee specific driver registration
  tpm/tpm_ftpm_tee: Make use of tee bus methods

 Documentation/driver-api/tee.rst             | 18 +----
 drivers/char/hw_random/optee-rng.c           | 26 ++----
 drivers/char/tpm/tpm_ftpm_tee.c              | 31 +++++---
 drivers/firmware/arm_scmi/transports/optee.c | 32 +++-----
 drivers/firmware/broadcom/tee_bnxt_fw.c      | 30 ++-----
 drivers/firmware/efi/stmm/tee_stmm_efi.c     | 25 ++----
 drivers/rtc/rtc-optee.c                      | 27 ++-----
 drivers/tee/tee_core.c                       | 84 ++++++++++++++++++++
 include/linux/tee_drv.h                      | 12 +++
 security/keys/trusted-keys/trusted_tee.c     | 17 ++--
 10 files changed, 164 insertions(+), 138 deletions(-)


base-commit: 7d0a66e4bb9081d75c82ec4957c50034cb0ea449
-- 
2.47.3

[PATCH v1 01/17] tee: Add some helpers to reduce boilerplate for tee client drivers

[Uwe Kleine-König]

Similar to platform drivers (and others) create dedicated register and
unregister functions and a macro to simplify modules that only need to
handle driver registration in their init and exit handlers.

Signed-off-by: Uwe Kleine-König <u.kleine-koenig@baylibre.com>
---
 drivers/tee/tee_core.c  | 16 ++++++++++++++++
 include/linux/tee_drv.h |  9 +++++++++
 2 files changed, 25 insertions(+)

diff --git a/drivers/tee/tee_core.c b/drivers/tee/tee_core.c
index d65d47cc154e..51379f7fc5d5 100644
--- a/drivers/tee/tee_core.c
+++ b/drivers/tee/tee_core.c
@@ -1405,6 +1405,22 @@ const struct bus_type tee_bus_type = {
 };
 EXPORT_SYMBOL_GPL(tee_bus_type);
 
+int __tee_client_driver_register(struct tee_client_driver *tee_driver,
+				 struct module *owner)
+{
+	tee_driver->driver.owner = owner;
+	tee_driver->driver.bus = &tee_bus_type;
+
+	return driver_register(&tee_driver->driver);
+}
+EXPORT_SYMBOL_GPL(__tee_client_driver_register);
+
+void tee_client_driver_unregister(struct tee_client_driver *tee_driver)
+{
+	driver_unregister(&tee_driver->driver);
+}
+EXPORT_SYMBOL_GPL(tee_client_driver_unregister);
+
 static int __init tee_init(void)
 {
 	int rc;
diff --git a/include/linux/tee_drv.h b/include/linux/tee_drv.h
index 88a6f9697c89..850c03b2cdea 100644
--- a/include/linux/tee_drv.h
+++ b/include/linux/tee_drv.h
@@ -322,4 +322,13 @@ struct tee_client_driver {
 #define to_tee_client_driver(d) \
 		container_of_const(d, struct tee_client_driver, driver)
 
+#define tee_client_driver_register(drv) \
+        __tee_client_driver_register(drv, THIS_MODULE)
+int __tee_client_driver_register(struct tee_client_driver *, struct module *);
+void tee_client_driver_unregister(struct tee_client_driver *);
+
+#define module_tee_client_driver(__tee_client_driver) \
+	module_driver(__tee_client_driver, tee_client_driver_register, \
+		      tee_client_driver_unregister)
+
 #endif /*__TEE_DRV_H*/
-- 
2.47.3

[PATCH v1 02/17] tee: Add probe, remove and shutdown bus callbacks to tee_client_driver

[Uwe Kleine-König]

Introduce a bus specific probe, remove and shutdown function. For now
this only allows to get rid of a cast of the generic device to a
tee_client device in the drivers and changes the remove prototype to
return void---a non-zero return value is ignored anyhow.

The objective is to get rid of users of struct device_driver callbacks
.probe(), .remove() and .shutdown() to eventually remove these. Until
all tee_client drivers are converted this results in a runtime warning
about the drivers needing an update because there is a bus probe
function and a driver probe function.

Signed-off-by: Uwe Kleine-König <u.kleine-koenig@baylibre.com>
---
 drivers/tee/tee_core.c  | 68 +++++++++++++++++++++++++++++++++++++++++
 include/linux/tee_drv.h |  3 ++
 2 files changed, 71 insertions(+)

diff --git a/drivers/tee/tee_core.c b/drivers/tee/tee_core.c
index 51379f7fc5d5..89164d35fc5c 100644
--- a/drivers/tee/tee_core.c
+++ b/drivers/tee/tee_core.c
@@ -1398,19 +1398,87 @@ static int tee_client_device_uevent(const struct device *dev,
 	return add_uevent_var(env, "MODALIAS=tee:%pUb", dev_id);
 }
 
+static int tee_client_device_probe(struct device *dev)
+{
+	struct tee_client_device *tcdev= to_tee_client_device(dev);
+	struct tee_client_driver *drv = to_tee_client_driver(dev->driver);
+
+	if (drv->probe)
+		return drv->probe(tcdev);
+	else
+		return 0;
+}
+
+static void tee_client_device_remove(struct device *dev)
+{
+	struct tee_client_device *tcdev= to_tee_client_device(dev);
+	struct tee_client_driver *drv = to_tee_client_driver(dev->driver);
+
+	if (drv->remove)
+		drv->remove(tcdev);
+}
+
+static void tee_client_device_shutdown(struct device *dev)
+{
+	struct tee_client_device *tcdev= to_tee_client_device(dev);
+	struct tee_client_driver *drv = to_tee_client_driver(dev->driver);
+
+	if (dev->driver && drv->remove)
+		drv->remove(tcdev);
+}
+
 const struct bus_type tee_bus_type = {
 	.name		= "tee",
 	.match		= tee_client_device_match,
 	.uevent		= tee_client_device_uevent,
+	.probe		= tee_client_device_probe,
+	.remove		= tee_client_device_remove,
+	.shutdown	= tee_client_device_shutdown,
 };
 EXPORT_SYMBOL_GPL(tee_bus_type);
 
+static int tee_client_device_probe_legacy(struct tee_client_device *tcdev)
+{
+	struct device *dev = &tcdev->dev;
+	struct device_driver *driver = dev->driver;
+
+	return driver->probe(dev);
+}
+
+static void tee_client_device_remove_legacy(struct tee_client_device *tcdev)
+{
+	struct device *dev = &tcdev->dev;
+	struct device_driver *driver = dev->driver;
+
+	driver->remove(dev);
+}
+
+static void tee_client_device_shutdown_legacy(struct tee_client_device *tcdev)
+{
+	struct device *dev = &tcdev->dev;
+	struct device_driver *driver = dev->driver;
+
+	driver->shutdown(dev);
+}
+
 int __tee_client_driver_register(struct tee_client_driver *tee_driver,
 				 struct module *owner)
 {
 	tee_driver->driver.owner = owner;
 	tee_driver->driver.bus = &tee_bus_type;
 
+	/*
+	 * Drivers that have callbacks set for tee_driver->driver need updating
+	 * to use the callbacks in tee_driver instead. driver_register() warns
+	 * about that, so no need to warn here, too.
+	 */
+	if (!tee_driver->probe && tee_driver->driver.probe)
+		tee_driver->probe = tee_client_device_probe_legacy;
+	if (!tee_driver->remove && tee_driver->driver.remove)
+		tee_driver->remove= tee_client_device_remove_legacy;
+	if (!tee_driver->shutdown && tee_driver->driver.probe)
+		tee_driver->shutdown = tee_client_device_shutdown_legacy;
+
 	return driver_register(&tee_driver->driver);
 }
 EXPORT_SYMBOL_GPL(__tee_client_driver_register);
diff --git a/include/linux/tee_drv.h b/include/linux/tee_drv.h
index 850c03b2cdea..e561a26f537a 100644
--- a/include/linux/tee_drv.h
+++ b/include/linux/tee_drv.h
@@ -315,6 +315,9 @@ struct tee_client_device {
  * @driver:		driver structure
  */
 struct tee_client_driver {
+	int (*probe)(struct tee_client_device *);
+	void (*remove)(struct tee_client_device *);
+	void (*shutdown)(struct tee_client_device *);
 	const struct tee_client_device_id *id_table;
 	struct device_driver driver;
 };
-- 
2.47.3

[PATCH v1 03/17] tee: Adapt documentation to cover recent additions

[Uwe Kleine-König]

The previous commits introduced some helpers to reduce boilerplate
and bus specific callbacks for probe and remove.

Adapt the reference example to make use of these.

Signed-off-by: Uwe Kleine-König <u.kleine-koenig@baylibre.com>
---
 Documentation/driver-api/tee.rst | 18 +++---------------
 1 file changed, 3 insertions(+), 15 deletions(-)

diff --git a/Documentation/driver-api/tee.rst b/Documentation/driver-api/tee.rst
index 5eaeb8103988..4d58ac0712c1 100644
--- a/Documentation/driver-api/tee.rst
+++ b/Documentation/driver-api/tee.rst
@@ -43,24 +43,12 @@ snippet would look like::
 	MODULE_DEVICE_TABLE(tee, client_id_table);
 
 	static struct tee_client_driver client_driver = {
+		.probe		= client_probe,
+		.remove		= client_remove,
 		.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);
+	module_tee_client_driver(client_driver);
-- 
2.47.3

[PATCH v1 04/17] hwrng: optee - Make use of module_tee_client_driver()

[Uwe Kleine-König]

Reduce boilerplate by using the newly introduced module_tee_client_driver().
That takes care of assigning the driver's bus, so the explicit assigning
in this driver can be dropped.

Signed-off-by: Uwe Kleine-König <u.kleine-koenig@baylibre.com>
---
 drivers/char/hw_random/optee-rng.c | 14 +-------------
 1 file changed, 1 insertion(+), 13 deletions(-)

diff --git a/drivers/char/hw_random/optee-rng.c b/drivers/char/hw_random/optee-rng.c
index 96b5d546d136..6ee748c0cf57 100644
--- a/drivers/char/hw_random/optee-rng.c
+++ b/drivers/char/hw_random/optee-rng.c
@@ -281,24 +281,12 @@ static struct tee_client_driver optee_rng_driver = {
 	.id_table	= optee_rng_id_table,
 	.driver		= {
 		.name		= DRIVER_NAME,
-		.bus		= &tee_bus_type,
 		.probe		= optee_rng_probe,
 		.remove		= optee_rng_remove,
 	},
 };
 
-static int __init optee_rng_mod_init(void)
-{
-	return driver_register(&optee_rng_driver.driver);
-}
-
-static void __exit optee_rng_mod_exit(void)
-{
-	driver_unregister(&optee_rng_driver.driver);
-}
-
-module_init(optee_rng_mod_init);
-module_exit(optee_rng_mod_exit);
+module_tee_client_driver(optee_rng_driver);
 
 MODULE_LICENSE("GPL v2");
 MODULE_AUTHOR("Sumit Garg <sumit.garg@linaro.org>");
-- 
2.47.3

[PATCH v1 05/17] hwrng: optee - Make use of tee bus methods

[Uwe Kleine-König]

The tee bus got dedicated callbacks for probe and remove.
Make use of these. This fixes a runtime warning about the driver needing
to be converted to the bus methods.

Signed-off-by: Uwe Kleine-König <u.kleine-koenig@baylibre.com>
---
 drivers/char/hw_random/optee-rng.c | 12 +++++-------
 1 file changed, 5 insertions(+), 7 deletions(-)

diff --git a/drivers/char/hw_random/optee-rng.c b/drivers/char/hw_random/optee-rng.c
index 6ee748c0cf57..5a3fa0b38497 100644
--- a/drivers/char/hw_random/optee-rng.c
+++ b/drivers/char/hw_random/optee-rng.c
@@ -211,9 +211,9 @@ static int optee_ctx_match(struct tee_ioctl_version_data *ver, const void *data)
 		return 0;
 }
 
-static int optee_rng_probe(struct device *dev)
+static int optee_rng_probe(struct tee_client_device *rng_device)
 {
-	struct tee_client_device *rng_device = to_tee_client_device(dev);
+	struct device *dev = &rng_device->dev;
 	int ret = 0, err = -ENODEV;
 	struct tee_ioctl_open_session_arg sess_arg;
 
@@ -261,12 +261,10 @@ static int optee_rng_probe(struct device *dev)
 	return err;
 }
 
-static int optee_rng_remove(struct device *dev)
+static void optee_rng_remove(struct tee_client_device *tee_dev)
 {
 	tee_client_close_session(pvt_data.ctx, pvt_data.session_id);
 	tee_client_close_context(pvt_data.ctx);
-
-	return 0;
 }
 
 static const struct tee_client_device_id optee_rng_id_table[] = {
@@ -278,11 +276,11 @@ static const struct tee_client_device_id optee_rng_id_table[] = {
 MODULE_DEVICE_TABLE(tee, optee_rng_id_table);
 
 static struct tee_client_driver optee_rng_driver = {
+	.probe		= optee_rng_probe,
+	.remove		= optee_rng_remove,
 	.id_table	= optee_rng_id_table,
 	.driver		= {
 		.name		= DRIVER_NAME,
-		.probe		= optee_rng_probe,
-		.remove		= optee_rng_remove,
 	},
 };
 
-- 
2.47.3

[PATCH v1 06/17] rtc: optee: Migrate to use tee specific driver registration function

[Uwe Kleine-König]

The tee subsystem recently got a set of dedicated functions to register
(and unregister) a tee driver. Make use of them. These care for setting the
driver's bus (so the explicit assignment can be dropped) and the driver
owner (which is an improvement this driver benefits from).

Signed-off-by: Uwe Kleine-König <u.kleine-koenig@baylibre.com>
---
 drivers/rtc/rtc-optee.c | 14 +-------------
 1 file changed, 1 insertion(+), 13 deletions(-)

diff --git a/drivers/rtc/rtc-optee.c b/drivers/rtc/rtc-optee.c
index 184c6d142801..f924a729ead0 100644
--- a/drivers/rtc/rtc-optee.c
+++ b/drivers/rtc/rtc-optee.c
@@ -726,25 +726,13 @@ static struct tee_client_driver optee_rtc_driver = {
 	.id_table	= optee_rtc_id_table,
 	.driver		= {
 		.name		= "optee_rtc",
-		.bus		= &tee_bus_type,
 		.probe		= optee_rtc_probe,
 		.remove		= optee_rtc_remove,
 		.pm		= pm_sleep_ptr(&optee_rtc_pm_ops),
 	},
 };
 
-static int __init optee_rtc_mod_init(void)
-{
-	return driver_register(&optee_rtc_driver.driver);
-}
-
-static void __exit optee_rtc_mod_exit(void)
-{
-	driver_unregister(&optee_rtc_driver.driver);
-}
-
-module_init(optee_rtc_mod_init);
-module_exit(optee_rtc_mod_exit);
+module_tee_client_driver(optee_rtc_driver);
 
 MODULE_LICENSE("GPL v2");
 MODULE_AUTHOR("Clément Léger <clement.leger@bootlin.com>");
-- 
2.47.3

[PATCH v1 07/17] rtc: optee: Make use of tee bus methods

[Uwe Kleine-König]

The tee bus got dedicated callbacks for probe and remove. Make use of
these. This fixes a runtime warning about the driver needing to be
converted to the bus methods.

Signed-off-by: Uwe Kleine-König <u.kleine-koenig@baylibre.com>
---
 drivers/rtc/rtc-optee.c | 13 ++++++-------
 1 file changed, 6 insertions(+), 7 deletions(-)

diff --git a/drivers/rtc/rtc-optee.c b/drivers/rtc/rtc-optee.c
index f924a729ead0..eefde789d194 100644
--- a/drivers/rtc/rtc-optee.c
+++ b/drivers/rtc/rtc-optee.c
@@ -547,9 +547,9 @@ static int optee_ctx_match(struct tee_ioctl_version_data *ver, const void *data)
 		return 0;
 }
 
-static int optee_rtc_probe(struct device *dev)
+static int optee_rtc_probe(struct tee_client_device *rtc_device)
 {
-	struct tee_client_device *rtc_device = to_tee_client_device(dev);
+	struct device *dev = &rtc_device->dev;
 	struct tee_ioctl_open_session_arg sess2_arg = {0};
 	struct tee_ioctl_open_session_arg sess_arg = {0};
 	struct optee_rtc *priv;
@@ -682,8 +682,9 @@ static int optee_rtc_probe(struct device *dev)
 	return err;
 }
 
-static int optee_rtc_remove(struct device *dev)
+static void optee_rtc_remove(struct tee_client_device *rtc_device)
 {
+	struct device *dev = &rtc_device->dev;
 	struct optee_rtc *priv = dev_get_drvdata(dev);
 
 	if (priv->features & TA_RTC_FEATURE_ALARM) {
@@ -696,8 +697,6 @@ static int optee_rtc_remove(struct device *dev)
 	tee_shm_free(priv->shm);
 	tee_client_close_session(priv->ctx, priv->session_id);
 	tee_client_close_context(priv->ctx);
-
-	return 0;
 }
 
 static int optee_rtc_suspend(struct device *dev)
@@ -724,10 +723,10 @@ MODULE_DEVICE_TABLE(tee, optee_rtc_id_table);
 
 static struct tee_client_driver optee_rtc_driver = {
 	.id_table	= optee_rtc_id_table,
+	.probe		= optee_rtc_probe,
+	.remove		= optee_rtc_remove,
 	.driver		= {
 		.name		= "optee_rtc",
-		.probe		= optee_rtc_probe,
-		.remove		= optee_rtc_remove,
 		.pm		= pm_sleep_ptr(&optee_rtc_pm_ops),
 	},
 };
-- 
2.47.3

[PATCH v1 08/17] efi: stmm: Make use of module_tee_client_driver()

[Uwe Kleine-König]

Reduce boilerplate by using the newly introduced module_tee_client_driver().
That takes care of assigning the driver's bus, so the explicit assigning
in this driver can be dropped.

Signed-off-by: Uwe Kleine-König <u.kleine-koenig@baylibre.com>
---
 drivers/firmware/efi/stmm/tee_stmm_efi.c | 14 +-------------
 1 file changed, 1 insertion(+), 13 deletions(-)

diff --git a/drivers/firmware/efi/stmm/tee_stmm_efi.c b/drivers/firmware/efi/stmm/tee_stmm_efi.c
index 65c0fe1ba275..5903811858b6 100644
--- a/drivers/firmware/efi/stmm/tee_stmm_efi.c
+++ b/drivers/firmware/efi/stmm/tee_stmm_efi.c
@@ -584,24 +584,12 @@ static struct tee_client_driver tee_stmm_efi_driver = {
 	.id_table	= tee_stmm_efi_id_table,
 	.driver		= {
 		.name		= "tee-stmm-efi",
-		.bus		= &tee_bus_type,
 		.probe		= tee_stmm_efi_probe,
 		.remove		= tee_stmm_efi_remove,
 	},
 };
 
-static int __init tee_stmm_efi_mod_init(void)
-{
-	return driver_register(&tee_stmm_efi_driver.driver);
-}
-
-static void __exit tee_stmm_efi_mod_exit(void)
-{
-	driver_unregister(&tee_stmm_efi_driver.driver);
-}
-
-module_init(tee_stmm_efi_mod_init);
-module_exit(tee_stmm_efi_mod_exit);
+module_tee_client_driver(tee_stmm_efi_driver);
 
 MODULE_LICENSE("GPL");
 MODULE_AUTHOR("Ilias Apalodimas <ilias.apalodimas@linaro.org>");
-- 
2.47.3

[PATCH v1 09/17] efi: stmm: Make use of tee bus methods

[Uwe Kleine-König]

The tee bus got dedicated callbacks for probe and remove.
Make use of these. This fixes a runtime warning about the driver needing
to be converted to the bus methods.

Signed-off-by: Uwe Kleine-König <u.kleine-koenig@baylibre.com>
---
 drivers/firmware/efi/stmm/tee_stmm_efi.c | 11 +++++------
 1 file changed, 5 insertions(+), 6 deletions(-)

diff --git a/drivers/firmware/efi/stmm/tee_stmm_efi.c b/drivers/firmware/efi/stmm/tee_stmm_efi.c
index 5903811858b6..7b04dd649629 100644
--- a/drivers/firmware/efi/stmm/tee_stmm_efi.c
+++ b/drivers/firmware/efi/stmm/tee_stmm_efi.c
@@ -520,8 +520,9 @@ static void tee_stmm_restore_efivars_generic_ops(void)
 	efivars_generic_ops_register();
 }
 
-static int tee_stmm_efi_probe(struct device *dev)
+static int tee_stmm_efi_probe(struct tee_client_device *tee_dev)
 {
+	struct device *dev = &tee_dev->dev;
 	struct tee_ioctl_open_session_arg sess_arg;
 	efi_status_t ret;
 	int rc;
@@ -571,21 +572,19 @@ static int tee_stmm_efi_probe(struct device *dev)
 	return 0;
 }
 
-static int tee_stmm_efi_remove(struct device *dev)
+static void tee_stmm_efi_remove(struct tee_client_device *dev)
 {
 	tee_stmm_restore_efivars_generic_ops();
-
-	return 0;
 }
 
 MODULE_DEVICE_TABLE(tee, tee_stmm_efi_id_table);
 
 static struct tee_client_driver tee_stmm_efi_driver = {
 	.id_table	= tee_stmm_efi_id_table,
+	.probe		= tee_stmm_efi_probe,
+	.remove		= tee_stmm_efi_remove,
 	.driver		= {
 		.name		= "tee-stmm-efi",
-		.probe		= tee_stmm_efi_probe,
-		.remove		= tee_stmm_efi_remove,
 	},
 };
 
-- 
2.47.3

[PATCH v1 10/17] firmware: arm_scmi: optee: Make use of module_tee_client_driver()

[Uwe Kleine-König]

Reduce boilerplate by using the newly introduced module_tee_client_driver().
That takes care of assigning the driver's bus, so the explicit assigning
in this driver can be dropped.

Signed-off-by: Uwe Kleine-König <u.kleine-koenig@baylibre.com>
---
 drivers/firmware/arm_scmi/transports/optee.c | 13 +------------
 1 file changed, 1 insertion(+), 12 deletions(-)

diff --git a/drivers/firmware/arm_scmi/transports/optee.c b/drivers/firmware/arm_scmi/transports/optee.c
index dc0f46340153..8fdb80d3fabd 100644
--- a/drivers/firmware/arm_scmi/transports/optee.c
+++ b/drivers/firmware/arm_scmi/transports/optee.c
@@ -612,23 +612,12 @@ static struct tee_client_driver scmi_optee_service_driver = {
 	.id_table	= scmi_optee_service_id,
 	.driver		= {
 		.name = "scmi-optee",
-		.bus = &tee_bus_type,
 		.probe = scmi_optee_service_probe,
 		.remove = scmi_optee_service_remove,
 	},
 };
 
-static int __init scmi_transport_optee_init(void)
-{
-	return driver_register(&scmi_optee_service_driver.driver);
-}
-module_init(scmi_transport_optee_init);
-
-static void __exit scmi_transport_optee_exit(void)
-{
-	driver_unregister(&scmi_optee_service_driver.driver);
-}
-module_exit(scmi_transport_optee_exit);
+module_tee_client_driver(scmi_optee_service_driver);
 
 MODULE_AUTHOR("Etienne Carriere <etienne.carriere@foss.st.com>");
 MODULE_DESCRIPTION("SCMI OPTEE Transport driver");
-- 
2.47.3

[PATCH v1 11/17] firmware: arm_scmi: Make use of tee bus methods

[Uwe Kleine-König]

The tee bus got dedicated callbacks for probe and remove.
Make use of these. This fixes a runtime warning about the driver needing
to be converted to the bus methods. Note that the return value of .remove()
was already ignored before, so there is no problem introduced by dropping
the error returns.

Signed-off-by: Uwe Kleine-König <u.kleine-koenig@baylibre.com>
---
 drivers/firmware/arm_scmi/transports/optee.c | 19 +++++++++----------
 1 file changed, 9 insertions(+), 10 deletions(-)

diff --git a/drivers/firmware/arm_scmi/transports/optee.c b/drivers/firmware/arm_scmi/transports/optee.c
index 8fdb80d3fabd..07ae18d5279d 100644
--- a/drivers/firmware/arm_scmi/transports/optee.c
+++ b/drivers/firmware/arm_scmi/transports/optee.c
@@ -529,8 +529,9 @@ static const struct of_device_id scmi_of_match[] = {
 DEFINE_SCMI_TRANSPORT_DRIVER(scmi_optee, scmi_optee_driver, scmi_optee_desc,
 			     scmi_of_match, core);
 
-static int scmi_optee_service_probe(struct device *dev)
+static int scmi_optee_service_probe(struct tee_client_device *scmi_pta)
 {
+	struct device *dev = &scmi_pta->dev;
 	struct scmi_optee_agent *agent;
 	struct tee_context *tee_ctx;
 	int ret;
@@ -578,24 +579,22 @@ static int scmi_optee_service_probe(struct device *dev)
 	return ret;
 }
 
-static int scmi_optee_service_remove(struct device *dev)
+static void scmi_optee_service_remove(struct tee_client_device *scmi_pta)
 {
 	struct scmi_optee_agent *agent = scmi_optee_private;
 
 	if (!scmi_optee_private)
-		return -EINVAL;
+		return;
 
 	platform_driver_unregister(&scmi_optee_driver);
 
 	if (!list_empty(&scmi_optee_private->channel_list))
-		return -EBUSY;
+		return;
 
 	/* Ensure cleared reference is visible before resources are released */
 	smp_store_mb(scmi_optee_private, NULL);
 
 	tee_client_close_context(agent->tee_ctx);
-
-	return 0;
 }
 
 static const struct tee_client_device_id scmi_optee_service_id[] = {
@@ -609,11 +608,11 @@ static const struct tee_client_device_id scmi_optee_service_id[] = {
 MODULE_DEVICE_TABLE(tee, scmi_optee_service_id);
 
 static struct tee_client_driver scmi_optee_service_driver = {
-	.id_table	= scmi_optee_service_id,
-	.driver		= {
+	.probe = scmi_optee_service_probe,
+	.remove = scmi_optee_service_remove,
+	.id_table = scmi_optee_service_id,
+	.driver = {
 		.name = "scmi-optee",
-		.probe = scmi_optee_service_probe,
-		.remove = scmi_optee_service_remove,
 	},
 };
 
-- 
2.47.3

[PATCH v1 12/17] firmware: tee_bnxt: Make use of module_tee_client_driver()

[Uwe Kleine-König]

Reduce boilerplate by using the newly introduced module_tee_client_driver().
That takes care of assigning the driver's bus, so the explicit assigning
in this driver can be dropped.

Signed-off-by: Uwe Kleine-König <u.kleine-koenig@baylibre.com>
---
 drivers/firmware/broadcom/tee_bnxt_fw.c | 14 +-------------
 1 file changed, 1 insertion(+), 13 deletions(-)

diff --git a/drivers/firmware/broadcom/tee_bnxt_fw.c b/drivers/firmware/broadcom/tee_bnxt_fw.c
index 40e3183a3d11..fbdf1aa97c82 100644
--- a/drivers/firmware/broadcom/tee_bnxt_fw.c
+++ b/drivers/firmware/broadcom/tee_bnxt_fw.c
@@ -261,25 +261,13 @@ static struct tee_client_driver tee_bnxt_fw_driver = {
 	.id_table	= tee_bnxt_fw_id_table,
 	.driver		= {
 		.name		= KBUILD_MODNAME,
-		.bus		= &tee_bus_type,
 		.probe		= tee_bnxt_fw_probe,
 		.remove		= tee_bnxt_fw_remove,
 		.shutdown	= tee_bnxt_fw_shutdown,
 	},
 };
 
-static int __init tee_bnxt_fw_mod_init(void)
-{
-	return driver_register(&tee_bnxt_fw_driver.driver);
-}
-
-static void __exit tee_bnxt_fw_mod_exit(void)
-{
-	driver_unregister(&tee_bnxt_fw_driver.driver);
-}
-
-module_init(tee_bnxt_fw_mod_init);
-module_exit(tee_bnxt_fw_mod_exit);
+module_tee_client_driver(tee_bnxt_fw_driver);
 
 MODULE_AUTHOR("Vikas Gupta <vikas.gupta@broadcom.com>");
 MODULE_DESCRIPTION("Broadcom bnxt firmware manager");
-- 
2.47.3

[PATCH v1 13/17] firmware: tee_bnxt: Make use of tee bus methods

[Uwe Kleine-König]

The tee bus got dedicated callbacks for probe and remove.
Make use of these. This fixes a runtime warning about the driver needing
to be converted to the bus methods.

Signed-off-by: Uwe Kleine-König <u.kleine-koenig@baylibre.com>
---
 drivers/firmware/broadcom/tee_bnxt_fw.c | 16 +++++++---------
 1 file changed, 7 insertions(+), 9 deletions(-)

diff --git a/drivers/firmware/broadcom/tee_bnxt_fw.c b/drivers/firmware/broadcom/tee_bnxt_fw.c
index fbdf1aa97c82..a706c84eb2b6 100644
--- a/drivers/firmware/broadcom/tee_bnxt_fw.c
+++ b/drivers/firmware/broadcom/tee_bnxt_fw.c
@@ -181,9 +181,9 @@ static int optee_ctx_match(struct tee_ioctl_version_data *ver, const void *data)
 	return (ver->impl_id == TEE_IMPL_ID_OPTEE);
 }
 
-static int tee_bnxt_fw_probe(struct device *dev)
+static int tee_bnxt_fw_probe(struct tee_client_device *bnxt_device)
 {
-	struct tee_client_device *bnxt_device = to_tee_client_device(dev);
+	struct device *dev = &bnxt_device->dev;
 	int ret, err = -ENODEV;
 	struct tee_ioctl_open_session_arg sess_arg;
 	struct tee_shm *fw_shm_pool;
@@ -231,17 +231,15 @@ static int tee_bnxt_fw_probe(struct device *dev)
 	return err;
 }
 
-static int tee_bnxt_fw_remove(struct device *dev)
+static void tee_bnxt_fw_remove(struct tee_client_device *bnxt_device)
 {
 	tee_shm_free(pvt_data.fw_shm_pool);
 	tee_client_close_session(pvt_data.ctx, pvt_data.session_id);
 	tee_client_close_context(pvt_data.ctx);
 	pvt_data.ctx = NULL;
-
-	return 0;
 }
 
-static void tee_bnxt_fw_shutdown(struct device *dev)
+static void tee_bnxt_fw_shutdown(struct tee_client_device *bnxt_device)
 {
 	tee_shm_free(pvt_data.fw_shm_pool);
 	tee_client_close_session(pvt_data.ctx, pvt_data.session_id);
@@ -258,12 +256,12 @@ static const struct tee_client_device_id tee_bnxt_fw_id_table[] = {
 MODULE_DEVICE_TABLE(tee, tee_bnxt_fw_id_table);
 
 static struct tee_client_driver tee_bnxt_fw_driver = {
+	.probe		= tee_bnxt_fw_probe,
+	.remove		= tee_bnxt_fw_remove,
+	.shutdown	= tee_bnxt_fw_shutdown,
 	.id_table	= tee_bnxt_fw_id_table,
 	.driver		= {
 		.name		= KBUILD_MODNAME,
-		.probe		= tee_bnxt_fw_probe,
-		.remove		= tee_bnxt_fw_remove,
-		.shutdown	= tee_bnxt_fw_shutdown,
 	},
 };
 
-- 
2.47.3

[PATCH v1 14/17] KEYS: trusted: Migrate to use tee specific driver registration function

[Uwe Kleine-König]

The tee subsystem recently got a set of dedicated functions to register
(and unregister) a tee driver. Make use of them. These care for setting the
driver's bus (so the explicit assignment can be dropped) and the driver
owner (which is an improvement this driver benefits from).

Signed-off-by: Uwe Kleine-König <u.kleine-koenig@baylibre.com>
---
 security/keys/trusted-keys/trusted_tee.c | 5 ++---
 1 file changed, 2 insertions(+), 3 deletions(-)

diff --git a/security/keys/trusted-keys/trusted_tee.c b/security/keys/trusted-keys/trusted_tee.c
index aa3d477de6db..3cea9a377955 100644
--- a/security/keys/trusted-keys/trusted_tee.c
+++ b/security/keys/trusted-keys/trusted_tee.c
@@ -264,7 +264,6 @@ static struct tee_client_driver trusted_key_driver = {
 	.id_table	= trusted_key_id_table,
 	.driver		= {
 		.name		= DRIVER_NAME,
-		.bus		= &tee_bus_type,
 		.probe		= trusted_key_probe,
 		.remove		= trusted_key_remove,
 	},
@@ -272,12 +271,12 @@ static struct tee_client_driver trusted_key_driver = {
 
 static int trusted_tee_init(void)
 {
-	return driver_register(&trusted_key_driver.driver);
+	return tee_client_driver_register(&trusted_key_driver);
 }
 
 static void trusted_tee_exit(void)
 {
-	driver_unregister(&trusted_key_driver.driver);
+	tee_client_driver_unregister(&trusted_key_driver);
 }
 
 struct trusted_key_ops trusted_key_tee_ops = {
-- 
2.47.3

[PATCH v1 15/17] KEYS: trusted: Make use of tee bus methods

[Uwe Kleine-König]

The tee bus got dedicated callbacks for probe and remove.
Make use of these. This fixes a runtime warning about the driver needing
to be converted to the bus methods.

Signed-off-by: Uwe Kleine-König <u.kleine-koenig@baylibre.com>
---
 security/keys/trusted-keys/trusted_tee.c | 12 +++++-------
 1 file changed, 5 insertions(+), 7 deletions(-)

diff --git a/security/keys/trusted-keys/trusted_tee.c b/security/keys/trusted-keys/trusted_tee.c
index 3cea9a377955..6e465c8bef5e 100644
--- a/security/keys/trusted-keys/trusted_tee.c
+++ b/security/keys/trusted-keys/trusted_tee.c
@@ -202,9 +202,9 @@ static int optee_ctx_match(struct tee_ioctl_version_data *ver, const void *data)
 		return 0;
 }
 
-static int trusted_key_probe(struct device *dev)
+static int trusted_key_probe(struct tee_client_device *rng_device)
 {
-	struct tee_client_device *rng_device = to_tee_client_device(dev);
+	struct device *dev = &rng_device->dev;
 	int ret;
 	struct tee_ioctl_open_session_arg sess_arg;
 
@@ -244,13 +244,11 @@ static int trusted_key_probe(struct device *dev)
 	return ret;
 }
 
-static int trusted_key_remove(struct device *dev)
+static void trusted_key_remove(struct tee_client_device *dev)
 {
 	unregister_key_type(&key_type_trusted);
 	tee_client_close_session(pvt_data.ctx, pvt_data.session_id);
 	tee_client_close_context(pvt_data.ctx);
-
-	return 0;
 }
 
 static const struct tee_client_device_id trusted_key_id_table[] = {
@@ -261,11 +259,11 @@ static const struct tee_client_device_id trusted_key_id_table[] = {
 MODULE_DEVICE_TABLE(tee, trusted_key_id_table);
 
 static struct tee_client_driver trusted_key_driver = {
+	.probe		= trusted_key_probe,
+	.remove		= trusted_key_remove,
 	.id_table	= trusted_key_id_table,
 	.driver		= {
 		.name		= DRIVER_NAME,
-		.probe		= trusted_key_probe,
-		.remove		= trusted_key_remove,
 	},
 };
 
-- 
2.47.3

[PATCH v1 16/17] tpm/tpm_ftpm_tee: Make use of tee specific driver registration

[Uwe Kleine-König]

tee_client_driver_register() is typed more strongly and cares about
assigning the driver's bus. Similar for tee_client_driver_unregister().

Make use of these functions.

Signed-off-by: Uwe Kleine-König <u.kleine-koenig@baylibre.com>
---
 drivers/char/tpm/tpm_ftpm_tee.c | 5 ++---
 1 file changed, 2 insertions(+), 3 deletions(-)

diff --git a/drivers/char/tpm/tpm_ftpm_tee.c b/drivers/char/tpm/tpm_ftpm_tee.c
index 4e63c30aeaf1..e5fbc70b0eca 100644
--- a/drivers/char/tpm/tpm_ftpm_tee.c
+++ b/drivers/char/tpm/tpm_ftpm_tee.c
@@ -338,7 +338,6 @@ static struct tee_client_driver ftpm_tee_driver = {
 	.id_table	= optee_ftpm_id_table,
 	.driver		= {
 		.name		= "optee-ftpm",
-		.bus		= &tee_bus_type,
 		.probe		= ftpm_tee_probe,
 		.remove		= ftpm_tee_remove,
 	},
@@ -352,7 +351,7 @@ static int __init ftpm_mod_init(void)
 	if (rc)
 		return rc;
 
-	rc = driver_register(&ftpm_tee_driver.driver);
+	rc = tee_client_driver_register(&ftpm_tee_driver);
 	if (rc) {
 		platform_driver_unregister(&ftpm_tee_plat_driver);
 		return rc;
@@ -364,7 +363,7 @@ static int __init ftpm_mod_init(void)
 static void __exit ftpm_mod_exit(void)
 {
 	platform_driver_unregister(&ftpm_tee_plat_driver);
-	driver_unregister(&ftpm_tee_driver.driver);
+	tee_client_driver_unregister(&ftpm_tee_driver);
 }
 
 module_init(ftpm_mod_init);
-- 
2.47.3

[PATCH v1 17/17] tpm/tpm_ftpm_tee: Make use of tee bus methods

[Uwe Kleine-König]

The tee bus got dedicated callbacks for probe and remove.
Make use of these. This fixes a runtime warning about the driver needing
to be converted to the bus methods.

Signed-off-by: Uwe Kleine-König <u.kleine-koenig@baylibre.com>
---
 drivers/char/tpm/tpm_ftpm_tee.c | 26 +++++++++++++++++++-------
 1 file changed, 19 insertions(+), 7 deletions(-)

diff --git a/drivers/char/tpm/tpm_ftpm_tee.c b/drivers/char/tpm/tpm_ftpm_tee.c
index e5fbc70b0eca..20294d1953a3 100644
--- a/drivers/char/tpm/tpm_ftpm_tee.c
+++ b/drivers/char/tpm/tpm_ftpm_tee.c
@@ -169,7 +169,7 @@ static int ftpm_tee_match(struct tee_ioctl_version_data *ver, const void *data)
  * Return:
  *	On success, 0. On failure, -errno.
  */
-static int ftpm_tee_probe(struct device *dev)
+static int ftpm_tee_probe_generic(struct device *dev)
 {
 	int rc;
 	struct tpm_chip *chip;
@@ -251,11 +251,18 @@ static int ftpm_tee_probe(struct device *dev)
 	return rc;
 }
 
+static int ftpm_tee_probe(struct tee_client_device *tcdev)
+{
+	struct device *dev = &tcdev->dev;
+
+	return ftpm_tee_probe_generic(dev);
+}
+
 static int ftpm_plat_tee_probe(struct platform_device *pdev)
 {
 	struct device *dev = &pdev->dev;
 
-	return ftpm_tee_probe(dev);
+	return ftpm_tee_probe_generic(dev);
 }
 
 /**
@@ -265,7 +272,7 @@ static int ftpm_plat_tee_probe(struct platform_device *pdev)
  * Return:
  *	0 always.
  */
-static int ftpm_tee_remove(struct device *dev)
+static void ftpm_tee_remove_generic(struct device *dev)
 {
 	struct ftpm_tee_private *pvt_data = dev_get_drvdata(dev);
 
@@ -285,15 +292,20 @@ static int ftpm_tee_remove(struct device *dev)
 	tee_client_close_context(pvt_data->ctx);
 
 	/* memory allocated with devm_kzalloc() is freed automatically */
+}
 
-	return 0;
+static void ftpm_tee_remove(struct tee_client_device *tcdev)
+{
+	struct device *dev = &tcdev->dev;
+
+	ftpm_tee_remove_generic(dev);
 }
 
 static void ftpm_plat_tee_remove(struct platform_device *pdev)
 {
 	struct device *dev = &pdev->dev;
 
-	ftpm_tee_remove(dev);
+	ftpm_tee_remove_generic(dev);
 }
 
 /**
@@ -335,11 +347,11 @@ static const struct tee_client_device_id optee_ftpm_id_table[] = {
 MODULE_DEVICE_TABLE(tee, optee_ftpm_id_table);
 
 static struct tee_client_driver ftpm_tee_driver = {
+	.probe		= ftpm_tee_probe,
+	.remove		= ftpm_tee_remove,
 	.id_table	= optee_ftpm_id_table,
 	.driver		= {
 		.name		= "optee-ftpm",
-		.probe		= ftpm_tee_probe,
-		.remove		= ftpm_tee_remove,
 	},
 };
 
-- 
2.47.3

Re: [PATCH v1 17/17] tpm/tpm_ftpm_tee: Make use of tee bus methods

[Jarkko Sakkinen]

On Thu, Dec 11, 2025 at 06:15:11PM +0100, Uwe Kleine-König wrote:
> The tee bus got dedicated callbacks for probe and remove.
> Make use of these. This fixes a runtime warning about the driver needing
> to be converted to the bus methods.
> 
> Signed-off-by: Uwe Kleine-König <u.kleine-koenig@baylibre.com>
> ---
>  drivers/char/tpm/tpm_ftpm_tee.c | 26 +++++++++++++++++++-------
>  1 file changed, 19 insertions(+), 7 deletions(-)
> 
> diff --git a/drivers/char/tpm/tpm_ftpm_tee.c b/drivers/char/tpm/tpm_ftpm_tee.c
> index e5fbc70b0eca..20294d1953a3 100644
> --- a/drivers/char/tpm/tpm_ftpm_tee.c
> +++ b/drivers/char/tpm/tpm_ftpm_tee.c
> @@ -169,7 +169,7 @@ static int ftpm_tee_match(struct tee_ioctl_version_data *ver, const void *data)
>   * Return:
>   *	On success, 0. On failure, -errno.
>   */
> -static int ftpm_tee_probe(struct device *dev)
> +static int ftpm_tee_probe_generic(struct device *dev)
>  {
>  	int rc;
>  	struct tpm_chip *chip;
> @@ -251,11 +251,18 @@ static int ftpm_tee_probe(struct device *dev)
>  	return rc;
>  }
>  
> +static int ftpm_tee_probe(struct tee_client_device *tcdev)
> +{
> +	struct device *dev = &tcdev->dev;
> +
> +	return ftpm_tee_probe_generic(dev);
> +}
> +
>  static int ftpm_plat_tee_probe(struct platform_device *pdev)
>  {
>  	struct device *dev = &pdev->dev;
>  
> -	return ftpm_tee_probe(dev);
> +	return ftpm_tee_probe_generic(dev);
>  }
>  
>  /**
> @@ -265,7 +272,7 @@ static int ftpm_plat_tee_probe(struct platform_device *pdev)
>   * Return:
>   *	0 always.
>   */
> -static int ftpm_tee_remove(struct device *dev)
> +static void ftpm_tee_remove_generic(struct device *dev)
>  {
>  	struct ftpm_tee_private *pvt_data = dev_get_drvdata(dev);
>  
> @@ -285,15 +292,20 @@ static int ftpm_tee_remove(struct device *dev)
>  	tee_client_close_context(pvt_data->ctx);
>  
>  	/* memory allocated with devm_kzalloc() is freed automatically */
> +}
>  
> -	return 0;
> +static void ftpm_tee_remove(struct tee_client_device *tcdev)
> +{
> +	struct device *dev = &tcdev->dev;
> +
> +	ftpm_tee_remove_generic(dev);
>  }
>  
>  static void ftpm_plat_tee_remove(struct platform_device *pdev)
>  {
>  	struct device *dev = &pdev->dev;
>  
> -	ftpm_tee_remove(dev);
> +	ftpm_tee_remove_generic(dev);
>  }
>  
>  /**
> @@ -335,11 +347,11 @@ static const struct tee_client_device_id optee_ftpm_id_table[] = {
>  MODULE_DEVICE_TABLE(tee, optee_ftpm_id_table);
>  
>  static struct tee_client_driver ftpm_tee_driver = {
> +	.probe		= ftpm_tee_probe,
> +	.remove		= ftpm_tee_remove,
>  	.id_table	= optee_ftpm_id_table,
>  	.driver		= {
>  		.name		= "optee-ftpm",
> -		.probe		= ftpm_tee_probe,
> -		.remove		= ftpm_tee_remove,
>  	},
>  };
>  
> -- 
> 2.47.3
> 

I checked trusted key patches and ftpm patches. I don't have anything
against merging them.

So for those four patches:

Reviewed-by: Jarkko Sakkinen <jarkko@kernel.org>

BR, Jarkko

Re: [PATCH v1 17/17] tpm/tpm_ftpm_tee: Make use of tee bus methods

[Jarkko Sakkinen]

On Thu, Dec 11, 2025 at 06:15:11PM +0100, Uwe Kleine-König wrote:
> The tee bus got dedicated callbacks for probe and remove.
> Make use of these. This fixes a runtime warning about the driver needing
> to be converted to the bus methods.
> 
> Signed-off-by: Uwe Kleine-König <u.kleine-koenig@baylibre.com>
> ---
>  drivers/char/tpm/tpm_ftpm_tee.c | 26 +++++++++++++++++++-------
>  1 file changed, 19 insertions(+), 7 deletions(-)
> 
> diff --git a/drivers/char/tpm/tpm_ftpm_tee.c b/drivers/char/tpm/tpm_ftpm_tee.c
> index e5fbc70b0eca..20294d1953a3 100644
> --- a/drivers/char/tpm/tpm_ftpm_tee.c
> +++ b/drivers/char/tpm/tpm_ftpm_tee.c
> @@ -169,7 +169,7 @@ static int ftpm_tee_match(struct tee_ioctl_version_data *ver, const void *data)
>   * Return:
>   *	On success, 0. On failure, -errno.
>   */
> -static int ftpm_tee_probe(struct device *dev)
> +static int ftpm_tee_probe_generic(struct device *dev)
>  {
>  	int rc;
>  	struct tpm_chip *chip;
> @@ -251,11 +251,18 @@ static int ftpm_tee_probe(struct device *dev)
>  	return rc;
>  }
>  
> +static int ftpm_tee_probe(struct tee_client_device *tcdev)
> +{
> +	struct device *dev = &tcdev->dev;
> +
> +	return ftpm_tee_probe_generic(dev);
> +}
> +
>  static int ftpm_plat_tee_probe(struct platform_device *pdev)
>  {
>  	struct device *dev = &pdev->dev;
>  
> -	return ftpm_tee_probe(dev);
> +	return ftpm_tee_probe_generic(dev);
>  }
>  
>  /**
> @@ -265,7 +272,7 @@ static int ftpm_plat_tee_probe(struct platform_device *pdev)
>   * Return:
>   *	0 always.
>   */
> -static int ftpm_tee_remove(struct device *dev)
> +static void ftpm_tee_remove_generic(struct device *dev)
>  {
>  	struct ftpm_tee_private *pvt_data = dev_get_drvdata(dev);
>  
> @@ -285,15 +292,20 @@ static int ftpm_tee_remove(struct device *dev)
>  	tee_client_close_context(pvt_data->ctx);
>  
>  	/* memory allocated with devm_kzalloc() is freed automatically */
> +}
>  
> -	return 0;
> +static void ftpm_tee_remove(struct tee_client_device *tcdev)
> +{
> +	struct device *dev = &tcdev->dev;
> +
> +	ftpm_tee_remove_generic(dev);
>  }
>  
>  static void ftpm_plat_tee_remove(struct platform_device *pdev)
>  {
>  	struct device *dev = &pdev->dev;
>  
> -	ftpm_tee_remove(dev);
> +	ftpm_tee_remove_generic(dev);
>  }
>  
>  /**
> @@ -335,11 +347,11 @@ static const struct tee_client_device_id optee_ftpm_id_table[] = {
>  MODULE_DEVICE_TABLE(tee, optee_ftpm_id_table);
>  
>  static struct tee_client_driver ftpm_tee_driver = {
> +	.probe		= ftpm_tee_probe,
> +	.remove		= ftpm_tee_remove,
>  	.id_table	= optee_ftpm_id_table,
>  	.driver		= {
>  		.name		= "optee-ftpm",
> -		.probe		= ftpm_tee_probe,
> -		.remove		= ftpm_tee_remove,
>  	},
>  };
>  
> -- 
> 2.47.3
> 

And also for this:

Reviewed-by: Jarkko Sakkinen <jarkko@kernel.org>

BR, Jarkko

Re: [PATCH v1 10/17] firmware: arm_scmi: optee: Make use of module_tee_client_driver()

[Sudeep Holla]

On Thu, Dec 11, 2025 at 06:15:04PM +0100, Uwe Kleine-König wrote:
> Reduce boilerplate by using the newly introduced module_tee_client_driver().
> That takes care of assigning the driver's bus, so the explicit assigning
> in this driver can be dropped.
> 

Reviewed-by: Sudeep Holla <sudeep.holla@arm.com>

-- 
Regards,
Sudeep

Re: [PATCH v1 11/17] firmware: arm_scmi: Make use of tee bus methods

[Sudeep Holla]

On Thu, Dec 11, 2025 at 06:15:05PM +0100, Uwe Kleine-König wrote:
> The tee bus got dedicated callbacks for probe and remove.
> Make use of these. This fixes a runtime warning about the driver needing
> to be converted to the bus methods. Note that the return value of .remove()
> was already ignored before, so there is no problem introduced by dropping
> the error returns.
> 

Reviewed-by: Sudeep Holla <sudeep.holla@arm.com>

-- 
Regards,
Sudeep

Re: [PATCH v1 01/17] tee: Add some helpers to reduce boilerplate for tee client drivers

[Sumit Garg]

On Thu, Dec 11, 2025 at 06:14:55PM +0100, Uwe Kleine-König wrote:
> Similar to platform drivers (and others) create dedicated register and
> unregister functions and a macro to simplify modules that only need to
> handle driver registration in their init and exit handlers.
> 
> Signed-off-by: Uwe Kleine-König <u.kleine-koenig@baylibre.com>
> ---
>  drivers/tee/tee_core.c  | 16 ++++++++++++++++
>  include/linux/tee_drv.h |  9 +++++++++
>  2 files changed, 25 insertions(+)

Reviewed-by: Sumit Garg <sumit.garg@oss.qualcomm.com>

-Sumit

> 
> diff --git a/drivers/tee/tee_core.c b/drivers/tee/tee_core.c
> index d65d47cc154e..51379f7fc5d5 100644
> --- a/drivers/tee/tee_core.c
> +++ b/drivers/tee/tee_core.c
> @@ -1405,6 +1405,22 @@ const struct bus_type tee_bus_type = {
>  };
>  EXPORT_SYMBOL_GPL(tee_bus_type);
>  
> +int __tee_client_driver_register(struct tee_client_driver *tee_driver,
> +				 struct module *owner)
> +{
> +	tee_driver->driver.owner = owner;
> +	tee_driver->driver.bus = &tee_bus_type;
> +
> +	return driver_register(&tee_driver->driver);
> +}
> +EXPORT_SYMBOL_GPL(__tee_client_driver_register);
> +
> +void tee_client_driver_unregister(struct tee_client_driver *tee_driver)
> +{
> +	driver_unregister(&tee_driver->driver);
> +}
> +EXPORT_SYMBOL_GPL(tee_client_driver_unregister);
> +
>  static int __init tee_init(void)
>  {
>  	int rc;
> diff --git a/include/linux/tee_drv.h b/include/linux/tee_drv.h
> index 88a6f9697c89..850c03b2cdea 100644
> --- a/include/linux/tee_drv.h
> +++ b/include/linux/tee_drv.h
> @@ -322,4 +322,13 @@ struct tee_client_driver {
>  #define to_tee_client_driver(d) \
>  		container_of_const(d, struct tee_client_driver, driver)
>  
> +#define tee_client_driver_register(drv) \
> +        __tee_client_driver_register(drv, THIS_MODULE)
> +int __tee_client_driver_register(struct tee_client_driver *, struct module *);
> +void tee_client_driver_unregister(struct tee_client_driver *);
> +
> +#define module_tee_client_driver(__tee_client_driver) \
> +	module_driver(__tee_client_driver, tee_client_driver_register, \
> +		      tee_client_driver_unregister)
> +
>  #endif /*__TEE_DRV_H*/
> -- 
> 2.47.3
> 

Re: [PATCH v1 02/17] tee: Add probe, remove and shutdown bus callbacks to tee_client_driver

[Sumit Garg]

On Thu, Dec 11, 2025 at 06:14:56PM +0100, Uwe Kleine-König wrote:
> Introduce a bus specific probe, remove and shutdown function. For now
> this only allows to get rid of a cast of the generic device to a
> tee_client device in the drivers and changes the remove prototype to
> return void---a non-zero return value is ignored anyhow.
> 
> The objective is to get rid of users of struct device_driver callbacks
> .probe(), .remove() and .shutdown() to eventually remove these. Until
> all tee_client drivers are converted this results in a runtime warning
> about the drivers needing an update because there is a bus probe
> function and a driver probe function.
> 
> Signed-off-by: Uwe Kleine-König <u.kleine-koenig@baylibre.com>
> ---
>  drivers/tee/tee_core.c  | 68 +++++++++++++++++++++++++++++++++++++++++
>  include/linux/tee_drv.h |  3 ++
>  2 files changed, 71 insertions(+)
> 
> diff --git a/drivers/tee/tee_core.c b/drivers/tee/tee_core.c
> index 51379f7fc5d5..89164d35fc5c 100644
> --- a/drivers/tee/tee_core.c
> +++ b/drivers/tee/tee_core.c
> @@ -1398,19 +1398,87 @@ static int tee_client_device_uevent(const struct device *dev,
>  	return add_uevent_var(env, "MODALIAS=tee:%pUb", dev_id);
>  }
>  
> +static int tee_client_device_probe(struct device *dev)
> +{
> +	struct tee_client_device *tcdev= to_tee_client_device(dev);

missing space: s/tcdev=/tcdev =/

> +	struct tee_client_driver *drv = to_tee_client_driver(dev->driver);
> +
> +	if (drv->probe)
> +		return drv->probe(tcdev);
> +	else
> +		return 0;
> +}
> +
> +static void tee_client_device_remove(struct device *dev)
> +{
> +	struct tee_client_device *tcdev= to_tee_client_device(dev);

ditto.

> +	struct tee_client_driver *drv = to_tee_client_driver(dev->driver);
> +
> +	if (drv->remove)
> +		drv->remove(tcdev);
> +}
> +
> +static void tee_client_device_shutdown(struct device *dev)
> +{
> +	struct tee_client_device *tcdev= to_tee_client_device(dev);

ditto.

> +	struct tee_client_driver *drv = to_tee_client_driver(dev->driver);
> +
> +	if (dev->driver && drv->remove)
> +		drv->remove(tcdev);

don't we need to check and invoke drv->shutdown here?

> +}
> +
>  const struct bus_type tee_bus_type = {
>  	.name		= "tee",
>  	.match		= tee_client_device_match,
>  	.uevent		= tee_client_device_uevent,
> +	.probe		= tee_client_device_probe,
> +	.remove		= tee_client_device_remove,
> +	.shutdown	= tee_client_device_shutdown,
>  };
>  EXPORT_SYMBOL_GPL(tee_bus_type);
>  
> +static int tee_client_device_probe_legacy(struct tee_client_device *tcdev)
> +{
> +	struct device *dev = &tcdev->dev;
> +	struct device_driver *driver = dev->driver;
> +
> +	return driver->probe(dev);
> +}
> +
> +static void tee_client_device_remove_legacy(struct tee_client_device *tcdev)
> +{
> +	struct device *dev = &tcdev->dev;
> +	struct device_driver *driver = dev->driver;
> +
> +	driver->remove(dev);
> +}
> +
> +static void tee_client_device_shutdown_legacy(struct tee_client_device *tcdev)
> +{
> +	struct device *dev = &tcdev->dev;
> +	struct device_driver *driver = dev->driver;
> +
> +	driver->shutdown(dev);
> +}
> +
>  int __tee_client_driver_register(struct tee_client_driver *tee_driver,
>  				 struct module *owner)
>  {
>  	tee_driver->driver.owner = owner;
>  	tee_driver->driver.bus = &tee_bus_type;
>  
> +	/*
> +	 * Drivers that have callbacks set for tee_driver->driver need updating
> +	 * to use the callbacks in tee_driver instead. driver_register() warns
> +	 * about that, so no need to warn here, too.
> +	 */
> +	if (!tee_driver->probe && tee_driver->driver.probe)
> +		tee_driver->probe = tee_client_device_probe_legacy;
> +	if (!tee_driver->remove && tee_driver->driver.remove)
> +		tee_driver->remove= tee_client_device_remove_legacy;

missing space: s/tee_driver->remove=/tee_driver->remove =/

> +	if (!tee_driver->shutdown && tee_driver->driver.probe)

you should rather check here for tee_driver->driver.shutdown?

-Sumit

> +		tee_driver->shutdown = tee_client_device_shutdown_legacy;
> +
>  	return driver_register(&tee_driver->driver);
>  }
>  EXPORT_SYMBOL_GPL(__tee_client_driver_register);
> diff --git a/include/linux/tee_drv.h b/include/linux/tee_drv.h
> index 850c03b2cdea..e561a26f537a 100644
> --- a/include/linux/tee_drv.h
> +++ b/include/linux/tee_drv.h
> @@ -315,6 +315,9 @@ struct tee_client_device {
>   * @driver:		driver structure
>   */
>  struct tee_client_driver {
> +	int (*probe)(struct tee_client_device *);
> +	void (*remove)(struct tee_client_device *);
> +	void (*shutdown)(struct tee_client_device *);
>  	const struct tee_client_device_id *id_table;
>  	struct device_driver driver;
>  };
> -- 
> 2.47.3
> 

Re: [PATCH v1 03/17] tee: Adapt documentation to cover recent additions

[Sumit Garg]

On Thu, Dec 11, 2025 at 06:14:57PM +0100, Uwe Kleine-König wrote:
> The previous commits introduced some helpers to reduce boilerplate
> and bus specific callbacks for probe and remove.
> 
> Adapt the reference example to make use of these.
> 
> Signed-off-by: Uwe Kleine-König <u.kleine-koenig@baylibre.com>
> ---
>  Documentation/driver-api/tee.rst | 18 +++---------------
>  1 file changed, 3 insertions(+), 15 deletions(-)

Reviewed-by: Sumit Garg <sumit.garg@oss.qualcomm.com>

-Sumit

> 
> diff --git a/Documentation/driver-api/tee.rst b/Documentation/driver-api/tee.rst
> index 5eaeb8103988..4d58ac0712c1 100644
> --- a/Documentation/driver-api/tee.rst
> +++ b/Documentation/driver-api/tee.rst
> @@ -43,24 +43,12 @@ snippet would look like::
>  	MODULE_DEVICE_TABLE(tee, client_id_table);
>  
>  	static struct tee_client_driver client_driver = {
> +		.probe		= client_probe,
> +		.remove		= client_remove,
>  		.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);
> +	module_tee_client_driver(client_driver);
> -- 
> 2.47.3
> 

Re: [PATCH v1 04/17] hwrng: optee - Make use of module_tee_client_driver()

[Sumit Garg]

nit for subject: s/hwrng: optee -/hwrng: optee:/

On Thu, Dec 11, 2025 at 06:14:58PM +0100, Uwe Kleine-König wrote:
> Reduce boilerplate by using the newly introduced module_tee_client_driver().
> That takes care of assigning the driver's bus, so the explicit assigning
> in this driver can be dropped.
> 
> Signed-off-by: Uwe Kleine-König <u.kleine-koenig@baylibre.com>
> ---
>  drivers/char/hw_random/optee-rng.c | 14 +-------------
>  1 file changed, 1 insertion(+), 13 deletions(-)
>

Reviewed-by: Sumit Garg <sumit.garg@oss.qualcomm.com>

-Sumit

> diff --git a/drivers/char/hw_random/optee-rng.c b/drivers/char/hw_random/optee-rng.c
> index 96b5d546d136..6ee748c0cf57 100644
> --- a/drivers/char/hw_random/optee-rng.c
> +++ b/drivers/char/hw_random/optee-rng.c
> @@ -281,24 +281,12 @@ static struct tee_client_driver optee_rng_driver = {
>  	.id_table	= optee_rng_id_table,
>  	.driver		= {
>  		.name		= DRIVER_NAME,
> -		.bus		= &tee_bus_type,
>  		.probe		= optee_rng_probe,
>  		.remove		= optee_rng_remove,
>  	},
>  };
>  
> -static int __init optee_rng_mod_init(void)
> -{
> -	return driver_register(&optee_rng_driver.driver);
> -}
> -
> -static void __exit optee_rng_mod_exit(void)
> -{
> -	driver_unregister(&optee_rng_driver.driver);
> -}
> -
> -module_init(optee_rng_mod_init);
> -module_exit(optee_rng_mod_exit);
> +module_tee_client_driver(optee_rng_driver);
>  
>  MODULE_LICENSE("GPL v2");
>  MODULE_AUTHOR("Sumit Garg <sumit.garg@linaro.org>");
> -- 
> 2.47.3
> 
> 

Re: [PATCH v1 05/17] hwrng: optee - Make use of tee bus methods

[Sumit Garg]

nit for subject: s/hwrng: optee -/hwrng: optee:/

On Thu, Dec 11, 2025 at 06:14:59PM +0100, Uwe Kleine-König wrote:
> The tee bus got dedicated callbacks for probe and remove.
> Make use of these. This fixes a runtime warning about the driver needing
> to be converted to the bus methods.
> 
> Signed-off-by: Uwe Kleine-König <u.kleine-koenig@baylibre.com>
> ---
>  drivers/char/hw_random/optee-rng.c | 12 +++++-------
>  1 file changed, 5 insertions(+), 7 deletions(-)

Reviewed-by: Sumit Garg <sumit.garg@oss.qualcomm.com>

-Sumit

> 
> diff --git a/drivers/char/hw_random/optee-rng.c b/drivers/char/hw_random/optee-rng.c
> index 6ee748c0cf57..5a3fa0b38497 100644
> --- a/drivers/char/hw_random/optee-rng.c
> +++ b/drivers/char/hw_random/optee-rng.c
> @@ -211,9 +211,9 @@ static int optee_ctx_match(struct tee_ioctl_version_data *ver, const void *data)
>  		return 0;
>  }
>  
> -static int optee_rng_probe(struct device *dev)
> +static int optee_rng_probe(struct tee_client_device *rng_device)
>  {
> -	struct tee_client_device *rng_device = to_tee_client_device(dev);
> +	struct device *dev = &rng_device->dev;
>  	int ret = 0, err = -ENODEV;
>  	struct tee_ioctl_open_session_arg sess_arg;
>  
> @@ -261,12 +261,10 @@ static int optee_rng_probe(struct device *dev)
>  	return err;
>  }
>  
> -static int optee_rng_remove(struct device *dev)
> +static void optee_rng_remove(struct tee_client_device *tee_dev)
>  {
>  	tee_client_close_session(pvt_data.ctx, pvt_data.session_id);
>  	tee_client_close_context(pvt_data.ctx);
> -
> -	return 0;
>  }
>  
>  static const struct tee_client_device_id optee_rng_id_table[] = {
> @@ -278,11 +276,11 @@ static const struct tee_client_device_id optee_rng_id_table[] = {
>  MODULE_DEVICE_TABLE(tee, optee_rng_id_table);
>  
>  static struct tee_client_driver optee_rng_driver = {
> +	.probe		= optee_rng_probe,
> +	.remove		= optee_rng_remove,
>  	.id_table	= optee_rng_id_table,
>  	.driver		= {
>  		.name		= DRIVER_NAME,
> -		.probe		= optee_rng_probe,
> -		.remove		= optee_rng_remove,
>  	},
>  };
>  
> -- 
> 2.47.3
> 

Re: [PATCH v1 06/17] rtc: optee: Migrate to use tee specific driver registration function

[Sumit Garg]

On Thu, Dec 11, 2025 at 06:15:00PM +0100, Uwe Kleine-König wrote:
> The tee subsystem recently got a set of dedicated functions to register
> (and unregister) a tee driver. Make use of them. These care for setting the
> driver's bus (so the explicit assignment can be dropped) and the driver
> owner (which is an improvement this driver benefits from).
> 
> Signed-off-by: Uwe Kleine-König <u.kleine-koenig@baylibre.com>
> ---
>  drivers/rtc/rtc-optee.c | 14 +-------------
>  1 file changed, 1 insertion(+), 13 deletions(-)

Reviewed-by: Sumit Garg <sumit.garg@oss.qualcomm.com>

-Sumit

> 
> diff --git a/drivers/rtc/rtc-optee.c b/drivers/rtc/rtc-optee.c
> index 184c6d142801..f924a729ead0 100644
> --- a/drivers/rtc/rtc-optee.c
> +++ b/drivers/rtc/rtc-optee.c
> @@ -726,25 +726,13 @@ static struct tee_client_driver optee_rtc_driver = {
>  	.id_table	= optee_rtc_id_table,
>  	.driver		= {
>  		.name		= "optee_rtc",
> -		.bus		= &tee_bus_type,
>  		.probe		= optee_rtc_probe,
>  		.remove		= optee_rtc_remove,
>  		.pm		= pm_sleep_ptr(&optee_rtc_pm_ops),
>  	},
>  };
>  
> -static int __init optee_rtc_mod_init(void)
> -{
> -	return driver_register(&optee_rtc_driver.driver);
> -}
> -
> -static void __exit optee_rtc_mod_exit(void)
> -{
> -	driver_unregister(&optee_rtc_driver.driver);
> -}
> -
> -module_init(optee_rtc_mod_init);
> -module_exit(optee_rtc_mod_exit);
> +module_tee_client_driver(optee_rtc_driver);
>  
>  MODULE_LICENSE("GPL v2");
>  MODULE_AUTHOR("Clément Léger <clement.leger@bootlin.com>");
> -- 
> 2.47.3
> 

Re: [PATCH v1 07/17] rtc: optee: Make use of tee bus methods

[Sumit Garg]

On Thu, Dec 11, 2025 at 06:15:01PM +0100, Uwe Kleine-König wrote:
> The tee bus got dedicated callbacks for probe and remove. Make use of
> these. This fixes a runtime warning about the driver needing to be
> converted to the bus methods.
> 
> Signed-off-by: Uwe Kleine-König <u.kleine-koenig@baylibre.com>
> ---
>  drivers/rtc/rtc-optee.c | 13 ++++++-------
>  1 file changed, 6 insertions(+), 7 deletions(-)

Reviewed-by: Sumit Garg <sumit.garg@oss.qualcomm.com>

-Sumit

> 
> diff --git a/drivers/rtc/rtc-optee.c b/drivers/rtc/rtc-optee.c
> index f924a729ead0..eefde789d194 100644
> --- a/drivers/rtc/rtc-optee.c
> +++ b/drivers/rtc/rtc-optee.c
> @@ -547,9 +547,9 @@ static int optee_ctx_match(struct tee_ioctl_version_data *ver, const void *data)
>  		return 0;
>  }
>  
> -static int optee_rtc_probe(struct device *dev)
> +static int optee_rtc_probe(struct tee_client_device *rtc_device)
>  {
> -	struct tee_client_device *rtc_device = to_tee_client_device(dev);
> +	struct device *dev = &rtc_device->dev;
>  	struct tee_ioctl_open_session_arg sess2_arg = {0};
>  	struct tee_ioctl_open_session_arg sess_arg = {0};
>  	struct optee_rtc *priv;
> @@ -682,8 +682,9 @@ static int optee_rtc_probe(struct device *dev)
>  	return err;
>  }
>  
> -static int optee_rtc_remove(struct device *dev)
> +static void optee_rtc_remove(struct tee_client_device *rtc_device)
>  {
> +	struct device *dev = &rtc_device->dev;
>  	struct optee_rtc *priv = dev_get_drvdata(dev);
>  
>  	if (priv->features & TA_RTC_FEATURE_ALARM) {
> @@ -696,8 +697,6 @@ static int optee_rtc_remove(struct device *dev)
>  	tee_shm_free(priv->shm);
>  	tee_client_close_session(priv->ctx, priv->session_id);
>  	tee_client_close_context(priv->ctx);
> -
> -	return 0;
>  }
>  
>  static int optee_rtc_suspend(struct device *dev)
> @@ -724,10 +723,10 @@ MODULE_DEVICE_TABLE(tee, optee_rtc_id_table);
>  
>  static struct tee_client_driver optee_rtc_driver = {
>  	.id_table	= optee_rtc_id_table,
> +	.probe		= optee_rtc_probe,
> +	.remove		= optee_rtc_remove,
>  	.driver		= {
>  		.name		= "optee_rtc",
> -		.probe		= optee_rtc_probe,
> -		.remove		= optee_rtc_remove,
>  		.pm		= pm_sleep_ptr(&optee_rtc_pm_ops),
>  	},
>  };
> -- 
> 2.47.3
> 

Re: [PATCH v1 10/17] firmware: arm_scmi: optee: Make use of module_tee_client_driver()

[Sumit Garg]

On Thu, Dec 11, 2025 at 06:15:04PM +0100, Uwe Kleine-König wrote:
> Reduce boilerplate by using the newly introduced module_tee_client_driver().
> That takes care of assigning the driver's bus, so the explicit assigning
> in this driver can be dropped.
> 
> Signed-off-by: Uwe Kleine-König <u.kleine-koenig@baylibre.com>
> ---
>  drivers/firmware/arm_scmi/transports/optee.c | 13 +------------
>  1 file changed, 1 insertion(+), 12 deletions(-)

Reviewed-by: Sumit Garg <sumit.garg@oss.qualcomm.com>

-Sumit

> 
> diff --git a/drivers/firmware/arm_scmi/transports/optee.c b/drivers/firmware/arm_scmi/transports/optee.c
> index dc0f46340153..8fdb80d3fabd 100644
> --- a/drivers/firmware/arm_scmi/transports/optee.c
> +++ b/drivers/firmware/arm_scmi/transports/optee.c
> @@ -612,23 +612,12 @@ static struct tee_client_driver scmi_optee_service_driver = {
>  	.id_table	= scmi_optee_service_id,
>  	.driver		= {
>  		.name = "scmi-optee",
> -		.bus = &tee_bus_type,
>  		.probe = scmi_optee_service_probe,
>  		.remove = scmi_optee_service_remove,
>  	},
>  };
>  
> -static int __init scmi_transport_optee_init(void)
> -{
> -	return driver_register(&scmi_optee_service_driver.driver);
> -}
> -module_init(scmi_transport_optee_init);
> -
> -static void __exit scmi_transport_optee_exit(void)
> -{
> -	driver_unregister(&scmi_optee_service_driver.driver);
> -}
> -module_exit(scmi_transport_optee_exit);
> +module_tee_client_driver(scmi_optee_service_driver);
>  
>  MODULE_AUTHOR("Etienne Carriere <etienne.carriere@foss.st.com>");
>  MODULE_DESCRIPTION("SCMI OPTEE Transport driver");
> -- 
> 2.47.3
> 

Re: [PATCH v1 11/17] firmware: arm_scmi: Make use of tee bus methods

[Sumit Garg]

On Thu, Dec 11, 2025 at 06:15:05PM +0100, Uwe Kleine-König wrote:
> The tee bus got dedicated callbacks for probe and remove.
> Make use of these. This fixes a runtime warning about the driver needing
> to be converted to the bus methods. Note that the return value of .remove()
> was already ignored before, so there is no problem introduced by dropping
> the error returns.
> 
> Signed-off-by: Uwe Kleine-König <u.kleine-koenig@baylibre.com>
> ---
>  drivers/firmware/arm_scmi/transports/optee.c | 19 +++++++++----------
>  1 file changed, 9 insertions(+), 10 deletions(-)

Reviewed-by: Sumit Garg <sumit.garg@oss.qualcomm.com>

-Sumit

> 
> diff --git a/drivers/firmware/arm_scmi/transports/optee.c b/drivers/firmware/arm_scmi/transports/optee.c
> index 8fdb80d3fabd..07ae18d5279d 100644
> --- a/drivers/firmware/arm_scmi/transports/optee.c
> +++ b/drivers/firmware/arm_scmi/transports/optee.c
> @@ -529,8 +529,9 @@ static const struct of_device_id scmi_of_match[] = {
>  DEFINE_SCMI_TRANSPORT_DRIVER(scmi_optee, scmi_optee_driver, scmi_optee_desc,
>  			     scmi_of_match, core);
>  
> -static int scmi_optee_service_probe(struct device *dev)
> +static int scmi_optee_service_probe(struct tee_client_device *scmi_pta)
>  {
> +	struct device *dev = &scmi_pta->dev;
>  	struct scmi_optee_agent *agent;
>  	struct tee_context *tee_ctx;
>  	int ret;
> @@ -578,24 +579,22 @@ static int scmi_optee_service_probe(struct device *dev)
>  	return ret;
>  }
>  
> -static int scmi_optee_service_remove(struct device *dev)
> +static void scmi_optee_service_remove(struct tee_client_device *scmi_pta)
>  {
>  	struct scmi_optee_agent *agent = scmi_optee_private;
>  
>  	if (!scmi_optee_private)
> -		return -EINVAL;
> +		return;
>  
>  	platform_driver_unregister(&scmi_optee_driver);
>  
>  	if (!list_empty(&scmi_optee_private->channel_list))
> -		return -EBUSY;
> +		return;
>  
>  	/* Ensure cleared reference is visible before resources are released */
>  	smp_store_mb(scmi_optee_private, NULL);
>  
>  	tee_client_close_context(agent->tee_ctx);
> -
> -	return 0;
>  }
>  
>  static const struct tee_client_device_id scmi_optee_service_id[] = {
> @@ -609,11 +608,11 @@ static const struct tee_client_device_id scmi_optee_service_id[] = {
>  MODULE_DEVICE_TABLE(tee, scmi_optee_service_id);
>  
>  static struct tee_client_driver scmi_optee_service_driver = {
> -	.id_table	= scmi_optee_service_id,
> -	.driver		= {
> +	.probe = scmi_optee_service_probe,
> +	.remove = scmi_optee_service_remove,
> +	.id_table = scmi_optee_service_id,
> +	.driver = {
>  		.name = "scmi-optee",
> -		.probe = scmi_optee_service_probe,
> -		.remove = scmi_optee_service_remove,
>  	},
>  };
>  
> -- 
> 2.47.3
> 
> 

Re: [PATCH v1 12/17] firmware: tee_bnxt: Make use of module_tee_client_driver()

[Sumit Garg]

On Thu, Dec 11, 2025 at 06:15:06PM +0100, Uwe Kleine-König wrote:
> Reduce boilerplate by using the newly introduced module_tee_client_driver().
> That takes care of assigning the driver's bus, so the explicit assigning
> in this driver can be dropped.
> 
> Signed-off-by: Uwe Kleine-König <u.kleine-koenig@baylibre.com>
> ---
>  drivers/firmware/broadcom/tee_bnxt_fw.c | 14 +-------------
>  1 file changed, 1 insertion(+), 13 deletions(-)

Reviewed-by: Sumit Garg <sumit.garg@oss.qualcomm.com>

-Sumit

> 
> diff --git a/drivers/firmware/broadcom/tee_bnxt_fw.c b/drivers/firmware/broadcom/tee_bnxt_fw.c
> index 40e3183a3d11..fbdf1aa97c82 100644
> --- a/drivers/firmware/broadcom/tee_bnxt_fw.c
> +++ b/drivers/firmware/broadcom/tee_bnxt_fw.c
> @@ -261,25 +261,13 @@ static struct tee_client_driver tee_bnxt_fw_driver = {
>  	.id_table	= tee_bnxt_fw_id_table,
>  	.driver		= {
>  		.name		= KBUILD_MODNAME,
> -		.bus		= &tee_bus_type,
>  		.probe		= tee_bnxt_fw_probe,
>  		.remove		= tee_bnxt_fw_remove,
>  		.shutdown	= tee_bnxt_fw_shutdown,
>  	},
>  };
>  
> -static int __init tee_bnxt_fw_mod_init(void)
> -{
> -	return driver_register(&tee_bnxt_fw_driver.driver);
> -}
> -
> -static void __exit tee_bnxt_fw_mod_exit(void)
> -{
> -	driver_unregister(&tee_bnxt_fw_driver.driver);
> -}
> -
> -module_init(tee_bnxt_fw_mod_init);
> -module_exit(tee_bnxt_fw_mod_exit);
> +module_tee_client_driver(tee_bnxt_fw_driver);
>  
>  MODULE_AUTHOR("Vikas Gupta <vikas.gupta@broadcom.com>");
>  MODULE_DESCRIPTION("Broadcom bnxt firmware manager");
> -- 
> 2.47.3
> 

Re: [PATCH v1 13/17] firmware: tee_bnxt: Make use of tee bus methods

[Sumit Garg]

On Thu, Dec 11, 2025 at 06:15:07PM +0100, Uwe Kleine-König wrote:
> The tee bus got dedicated callbacks for probe and remove.
> Make use of these. This fixes a runtime warning about the driver needing
> to be converted to the bus methods.
> 
> Signed-off-by: Uwe Kleine-König <u.kleine-koenig@baylibre.com>
> ---
>  drivers/firmware/broadcom/tee_bnxt_fw.c | 16 +++++++---------
>  1 file changed, 7 insertions(+), 9 deletions(-)

Reviewed-by: Sumit Garg <sumit.garg@oss.qualcomm.com>

-Sumit

> 
> diff --git a/drivers/firmware/broadcom/tee_bnxt_fw.c b/drivers/firmware/broadcom/tee_bnxt_fw.c
> index fbdf1aa97c82..a706c84eb2b6 100644
> --- a/drivers/firmware/broadcom/tee_bnxt_fw.c
> +++ b/drivers/firmware/broadcom/tee_bnxt_fw.c
> @@ -181,9 +181,9 @@ static int optee_ctx_match(struct tee_ioctl_version_data *ver, const void *data)
>  	return (ver->impl_id == TEE_IMPL_ID_OPTEE);
>  }
>  
> -static int tee_bnxt_fw_probe(struct device *dev)
> +static int tee_bnxt_fw_probe(struct tee_client_device *bnxt_device)
>  {
> -	struct tee_client_device *bnxt_device = to_tee_client_device(dev);
> +	struct device *dev = &bnxt_device->dev;
>  	int ret, err = -ENODEV;
>  	struct tee_ioctl_open_session_arg sess_arg;
>  	struct tee_shm *fw_shm_pool;
> @@ -231,17 +231,15 @@ static int tee_bnxt_fw_probe(struct device *dev)
>  	return err;
>  }
>  
> -static int tee_bnxt_fw_remove(struct device *dev)
> +static void tee_bnxt_fw_remove(struct tee_client_device *bnxt_device)
>  {
>  	tee_shm_free(pvt_data.fw_shm_pool);
>  	tee_client_close_session(pvt_data.ctx, pvt_data.session_id);
>  	tee_client_close_context(pvt_data.ctx);
>  	pvt_data.ctx = NULL;
> -
> -	return 0;
>  }
>  
> -static void tee_bnxt_fw_shutdown(struct device *dev)
> +static void tee_bnxt_fw_shutdown(struct tee_client_device *bnxt_device)
>  {
>  	tee_shm_free(pvt_data.fw_shm_pool);
>  	tee_client_close_session(pvt_data.ctx, pvt_data.session_id);
> @@ -258,12 +256,12 @@ static const struct tee_client_device_id tee_bnxt_fw_id_table[] = {
>  MODULE_DEVICE_TABLE(tee, tee_bnxt_fw_id_table);
>  
>  static struct tee_client_driver tee_bnxt_fw_driver = {
> +	.probe		= tee_bnxt_fw_probe,
> +	.remove		= tee_bnxt_fw_remove,
> +	.shutdown	= tee_bnxt_fw_shutdown,
>  	.id_table	= tee_bnxt_fw_id_table,
>  	.driver		= {
>  		.name		= KBUILD_MODNAME,
> -		.probe		= tee_bnxt_fw_probe,
> -		.remove		= tee_bnxt_fw_remove,
> -		.shutdown	= tee_bnxt_fw_shutdown,
>  	},
>  };
>  
> -- 
> 2.47.3
> 

Re: [PATCH v1 14/17] KEYS: trusted: Migrate to use tee specific driver registration function

[Sumit Garg]

On Thu, Dec 11, 2025 at 06:15:08PM +0100, Uwe Kleine-König wrote:
> The tee subsystem recently got a set of dedicated functions to register
> (and unregister) a tee driver. Make use of them. These care for setting the
> driver's bus (so the explicit assignment can be dropped) and the driver
> owner (which is an improvement this driver benefits from).
> 
> Signed-off-by: Uwe Kleine-König <u.kleine-koenig@baylibre.com>
> ---
>  security/keys/trusted-keys/trusted_tee.c | 5 ++---
>  1 file changed, 2 insertions(+), 3 deletions(-)

Reviewed-by: Sumit Garg <sumit.garg@oss.qualcomm.com>

-Sumit

> 
> diff --git a/security/keys/trusted-keys/trusted_tee.c b/security/keys/trusted-keys/trusted_tee.c
> index aa3d477de6db..3cea9a377955 100644
> --- a/security/keys/trusted-keys/trusted_tee.c
> +++ b/security/keys/trusted-keys/trusted_tee.c
> @@ -264,7 +264,6 @@ static struct tee_client_driver trusted_key_driver = {
>  	.id_table	= trusted_key_id_table,
>  	.driver		= {
>  		.name		= DRIVER_NAME,
> -		.bus		= &tee_bus_type,
>  		.probe		= trusted_key_probe,
>  		.remove		= trusted_key_remove,
>  	},
> @@ -272,12 +271,12 @@ static struct tee_client_driver trusted_key_driver = {
>  
>  static int trusted_tee_init(void)
>  {
> -	return driver_register(&trusted_key_driver.driver);
> +	return tee_client_driver_register(&trusted_key_driver);
>  }
>  
>  static void trusted_tee_exit(void)
>  {
> -	driver_unregister(&trusted_key_driver.driver);
> +	tee_client_driver_unregister(&trusted_key_driver);
>  }
>  
>  struct trusted_key_ops trusted_key_tee_ops = {
> -- 
> 2.47.3
> 

Re: [PATCH v1 15/17] KEYS: trusted: Make use of tee bus methods

[Sumit Garg]

On Thu, Dec 11, 2025 at 06:15:09PM +0100, Uwe Kleine-König wrote:
> The tee bus got dedicated callbacks for probe and remove.
> Make use of these. This fixes a runtime warning about the driver needing
> to be converted to the bus methods.
> 
> Signed-off-by: Uwe Kleine-König <u.kleine-koenig@baylibre.com>
> ---
>  security/keys/trusted-keys/trusted_tee.c | 12 +++++-------
>  1 file changed, 5 insertions(+), 7 deletions(-)

Reviewed-by: Sumit Garg <sumit.garg@oss.qualcomm.com>

-Sumit

> 
> diff --git a/security/keys/trusted-keys/trusted_tee.c b/security/keys/trusted-keys/trusted_tee.c
> index 3cea9a377955..6e465c8bef5e 100644
> --- a/security/keys/trusted-keys/trusted_tee.c
> +++ b/security/keys/trusted-keys/trusted_tee.c
> @@ -202,9 +202,9 @@ static int optee_ctx_match(struct tee_ioctl_version_data *ver, const void *data)
>  		return 0;
>  }
>  
> -static int trusted_key_probe(struct device *dev)
> +static int trusted_key_probe(struct tee_client_device *rng_device)
>  {
> -	struct tee_client_device *rng_device = to_tee_client_device(dev);
> +	struct device *dev = &rng_device->dev;
>  	int ret;
>  	struct tee_ioctl_open_session_arg sess_arg;
>  
> @@ -244,13 +244,11 @@ static int trusted_key_probe(struct device *dev)
>  	return ret;
>  }
>  
> -static int trusted_key_remove(struct device *dev)
> +static void trusted_key_remove(struct tee_client_device *dev)
>  {
>  	unregister_key_type(&key_type_trusted);
>  	tee_client_close_session(pvt_data.ctx, pvt_data.session_id);
>  	tee_client_close_context(pvt_data.ctx);
> -
> -	return 0;
>  }
>  
>  static const struct tee_client_device_id trusted_key_id_table[] = {
> @@ -261,11 +259,11 @@ static const struct tee_client_device_id trusted_key_id_table[] = {
>  MODULE_DEVICE_TABLE(tee, trusted_key_id_table);
>  
>  static struct tee_client_driver trusted_key_driver = {
> +	.probe		= trusted_key_probe,
> +	.remove		= trusted_key_remove,
>  	.id_table	= trusted_key_id_table,
>  	.driver		= {
>  		.name		= DRIVER_NAME,
> -		.probe		= trusted_key_probe,
> -		.remove		= trusted_key_remove,
>  	},
>  };
>  
> -- 
> 2.47.3
> 

Re: [PATCH v1 16/17] tpm/tpm_ftpm_tee: Make use of tee specific driver registration

[Sumit Garg]

On Thu, Dec 11, 2025 at 06:15:10PM +0100, Uwe Kleine-König wrote:
> tee_client_driver_register() is typed more strongly and cares about
> assigning the driver's bus. Similar for tee_client_driver_unregister().
> 
> Make use of these functions.
> 
> Signed-off-by: Uwe Kleine-König <u.kleine-koenig@baylibre.com>
> ---
>  drivers/char/tpm/tpm_ftpm_tee.c | 5 ++---
>  1 file changed, 2 insertions(+), 3 deletions(-)

Reviewed-by: Sumit Garg <sumit.garg@oss.qualcomm.com>

-Sumit

> 
> diff --git a/drivers/char/tpm/tpm_ftpm_tee.c b/drivers/char/tpm/tpm_ftpm_tee.c
> index 4e63c30aeaf1..e5fbc70b0eca 100644
> --- a/drivers/char/tpm/tpm_ftpm_tee.c
> +++ b/drivers/char/tpm/tpm_ftpm_tee.c
> @@ -338,7 +338,6 @@ static struct tee_client_driver ftpm_tee_driver = {
>  	.id_table	= optee_ftpm_id_table,
>  	.driver		= {
>  		.name		= "optee-ftpm",
> -		.bus		= &tee_bus_type,
>  		.probe		= ftpm_tee_probe,
>  		.remove		= ftpm_tee_remove,
>  	},
> @@ -352,7 +351,7 @@ static int __init ftpm_mod_init(void)
>  	if (rc)
>  		return rc;
>  
> -	rc = driver_register(&ftpm_tee_driver.driver);
> +	rc = tee_client_driver_register(&ftpm_tee_driver);
>  	if (rc) {
>  		platform_driver_unregister(&ftpm_tee_plat_driver);
>  		return rc;
> @@ -364,7 +363,7 @@ static int __init ftpm_mod_init(void)
>  static void __exit ftpm_mod_exit(void)
>  {
>  	platform_driver_unregister(&ftpm_tee_plat_driver);
> -	driver_unregister(&ftpm_tee_driver.driver);
> +	tee_client_driver_unregister(&ftpm_tee_driver);
>  }
>  
>  module_init(ftpm_mod_init);
> -- 
> 2.47.3
> 
> 

Re: [PATCH v1 17/17] tpm/tpm_ftpm_tee: Make use of tee bus methods

[Sumit Garg]

On Thu, Dec 11, 2025 at 06:15:11PM +0100, Uwe Kleine-König wrote:
> The tee bus got dedicated callbacks for probe and remove.
> Make use of these. This fixes a runtime warning about the driver needing
> to be converted to the bus methods.
> 
> Signed-off-by: Uwe Kleine-König <u.kleine-koenig@baylibre.com>
> ---
>  drivers/char/tpm/tpm_ftpm_tee.c | 26 +++++++++++++++++++-------
>  1 file changed, 19 insertions(+), 7 deletions(-)

Reviewed-by: Sumit Garg <sumit.garg@oss.qualcomm.com>

-Sumit

> 
> diff --git a/drivers/char/tpm/tpm_ftpm_tee.c b/drivers/char/tpm/tpm_ftpm_tee.c
> index e5fbc70b0eca..20294d1953a3 100644
> --- a/drivers/char/tpm/tpm_ftpm_tee.c
> +++ b/drivers/char/tpm/tpm_ftpm_tee.c
> @@ -169,7 +169,7 @@ static int ftpm_tee_match(struct tee_ioctl_version_data *ver, const void *data)
>   * Return:
>   *	On success, 0. On failure, -errno.
>   */
> -static int ftpm_tee_probe(struct device *dev)
> +static int ftpm_tee_probe_generic(struct device *dev)
>  {
>  	int rc;
>  	struct tpm_chip *chip;
> @@ -251,11 +251,18 @@ static int ftpm_tee_probe(struct device *dev)
>  	return rc;
>  }
>  
> +static int ftpm_tee_probe(struct tee_client_device *tcdev)
> +{
> +	struct device *dev = &tcdev->dev;
> +
> +	return ftpm_tee_probe_generic(dev);
> +}
> +
>  static int ftpm_plat_tee_probe(struct platform_device *pdev)
>  {
>  	struct device *dev = &pdev->dev;
>  
> -	return ftpm_tee_probe(dev);
> +	return ftpm_tee_probe_generic(dev);
>  }
>  
>  /**
> @@ -265,7 +272,7 @@ static int ftpm_plat_tee_probe(struct platform_device *pdev)
>   * Return:
>   *	0 always.
>   */
> -static int ftpm_tee_remove(struct device *dev)
> +static void ftpm_tee_remove_generic(struct device *dev)
>  {
>  	struct ftpm_tee_private *pvt_data = dev_get_drvdata(dev);
>  
> @@ -285,15 +292,20 @@ static int ftpm_tee_remove(struct device *dev)
>  	tee_client_close_context(pvt_data->ctx);
>  
>  	/* memory allocated with devm_kzalloc() is freed automatically */
> +}
>  
> -	return 0;
> +static void ftpm_tee_remove(struct tee_client_device *tcdev)
> +{
> +	struct device *dev = &tcdev->dev;
> +
> +	ftpm_tee_remove_generic(dev);
>  }
>  
>  static void ftpm_plat_tee_remove(struct platform_device *pdev)
>  {
>  	struct device *dev = &pdev->dev;
>  
> -	ftpm_tee_remove(dev);
> +	ftpm_tee_remove_generic(dev);
>  }
>  
>  /**
> @@ -335,11 +347,11 @@ static const struct tee_client_device_id optee_ftpm_id_table[] = {
>  MODULE_DEVICE_TABLE(tee, optee_ftpm_id_table);
>  
>  static struct tee_client_driver ftpm_tee_driver = {
> +	.probe		= ftpm_tee_probe,
> +	.remove		= ftpm_tee_remove,
>  	.id_table	= optee_ftpm_id_table,
>  	.driver		= {
>  		.name		= "optee-ftpm",
> -		.probe		= ftpm_tee_probe,
> -		.remove		= ftpm_tee_remove,
>  	},
>  };
>  
> -- 
> 2.47.3
> 
> 

Re: [PATCH v1 00/17] tee: Use bus callbacks instead of driver callbacks

[Sumit Garg]

On Thu, Dec 11, 2025 at 06:14:54PM +0100, Uwe Kleine-König wrote:
> Hello,
> 
> the objective of this series is to make tee driver stop using callbacks
> in struct device_driver. These were superseded by bus methods in 2006
> (commit 594c8281f905 ("[PATCH] Add bus_type probe, remove, shutdown
> methods.")) but nobody cared to convert all subsystems accordingly.
> 
> Here the tee drivers are converted. The first commit is somewhat
> unrelated, but simplifies the conversion (and the drivers). It
> introduces driver registration helpers that care about setting the bus
> and owner. (The latter is missing in all drivers, so by using these
> helpers the drivers become more correct.)
> 
> The patches #4 - #17 depend on the first two, so if they should be
> applied to their respective subsystem trees these must contain the first
> two patches first.

Thanks Uwe for your efforts to clean up the boilerplate code for TEE bus
drivers.

> 
> Note that after patch #2 is applied, unconverted drivers provoke a
> warning in driver_register(), so it would be good for the user
> experience if the whole series goes in during a single merge window.

+1

I suggest the whole series goes via the Jens tree since there shouldn't
be any chances for conflict here.

> So
> I guess an immutable branch containing the frist three patches that can
> be merged into the other subsystem trees would be sensible.
> 
> After all patches are applied, tee_bus_type can be made private to
> drivers/tee as it's not used in other places any more.
> 

Feel free to make the tee_bus_type private as the last patch in the series
such that any followup driver follows this clean approach.

-Sumit

> Best regards
> Uwe
> 
> Uwe Kleine-König (17):
>   tee: Add some helpers to reduce boilerplate for tee client drivers
>   tee: Add probe, remove and shutdown bus callbacks to tee_client_driver
>   tee: Adapt documentation to cover recent additions
>   hwrng: optee - Make use of module_tee_client_driver()
>   hwrng: optee - Make use of tee bus methods
>   rtc: optee: Migrate to use tee specific driver registration function
>   rtc: optee: Make use of tee bus methods
>   efi: stmm: Make use of module_tee_client_driver()
>   efi: stmm: Make use of tee bus methods
>   firmware: arm_scmi: optee: Make use of module_tee_client_driver()
>   firmware: arm_scmi: Make use of tee bus methods
>   firmware: tee_bnxt: Make use of module_tee_client_driver()
>   firmware: tee_bnxt: Make use of tee bus methods
>   KEYS: trusted: Migrate to use tee specific driver registration
>     function
>   KEYS: trusted: Make use of tee bus methods
>   tpm/tpm_ftpm_tee: Make use of tee specific driver registration
>   tpm/tpm_ftpm_tee: Make use of tee bus methods
> 
>  Documentation/driver-api/tee.rst             | 18 +----
>  drivers/char/hw_random/optee-rng.c           | 26 ++----
>  drivers/char/tpm/tpm_ftpm_tee.c              | 31 +++++---
>  drivers/firmware/arm_scmi/transports/optee.c | 32 +++-----
>  drivers/firmware/broadcom/tee_bnxt_fw.c      | 30 ++-----
>  drivers/firmware/efi/stmm/tee_stmm_efi.c     | 25 ++----
>  drivers/rtc/rtc-optee.c                      | 27 ++-----
>  drivers/tee/tee_core.c                       | 84 ++++++++++++++++++++
>  include/linux/tee_drv.h                      | 12 +++
>  security/keys/trusted-keys/trusted_tee.c     | 17 ++--
>  10 files changed, 164 insertions(+), 138 deletions(-)
> 
> 
> base-commit: 7d0a66e4bb9081d75c82ec4957c50034cb0ea449
> -- 
> 2.47.3
> 

Re: [PATCH v1 08/17] efi: stmm: Make use of module_tee_client_driver()

[Sumit Garg]

On Thu, Dec 11, 2025 at 06:15:02PM +0100, Uwe Kleine-König wrote:
> Reduce boilerplate by using the newly introduced module_tee_client_driver().
> That takes care of assigning the driver's bus, so the explicit assigning
> in this driver can be dropped.
> 
> Signed-off-by: Uwe Kleine-König <u.kleine-koenig@baylibre.com>
> ---
>  drivers/firmware/efi/stmm/tee_stmm_efi.c | 14 +-------------
>  1 file changed, 1 insertion(+), 13 deletions(-)

Reviewed-by: Sumit Garg <sumit.garg@oss.qualcomm.com>

-Sumit

> 
> diff --git a/drivers/firmware/efi/stmm/tee_stmm_efi.c b/drivers/firmware/efi/stmm/tee_stmm_efi.c
> index 65c0fe1ba275..5903811858b6 100644
> --- a/drivers/firmware/efi/stmm/tee_stmm_efi.c
> +++ b/drivers/firmware/efi/stmm/tee_stmm_efi.c
> @@ -584,24 +584,12 @@ static struct tee_client_driver tee_stmm_efi_driver = {
>  	.id_table	= tee_stmm_efi_id_table,
>  	.driver		= {
>  		.name		= "tee-stmm-efi",
> -		.bus		= &tee_bus_type,
>  		.probe		= tee_stmm_efi_probe,
>  		.remove		= tee_stmm_efi_remove,
>  	},
>  };
>  
> -static int __init tee_stmm_efi_mod_init(void)
> -{
> -	return driver_register(&tee_stmm_efi_driver.driver);
> -}
> -
> -static void __exit tee_stmm_efi_mod_exit(void)
> -{
> -	driver_unregister(&tee_stmm_efi_driver.driver);
> -}
> -
> -module_init(tee_stmm_efi_mod_init);
> -module_exit(tee_stmm_efi_mod_exit);
> +module_tee_client_driver(tee_stmm_efi_driver);
>  
>  MODULE_LICENSE("GPL");
>  MODULE_AUTHOR("Ilias Apalodimas <ilias.apalodimas@linaro.org>");
> -- 
> 2.47.3
> 
> 

Re: [PATCH v1 09/17] efi: stmm: Make use of tee bus methods

[Sumit Garg]

On Thu, Dec 11, 2025 at 06:15:03PM +0100, Uwe Kleine-König wrote:
> The tee bus got dedicated callbacks for probe and remove.
> Make use of these. This fixes a runtime warning about the driver needing
> to be converted to the bus methods.
> 
> Signed-off-by: Uwe Kleine-König <u.kleine-koenig@baylibre.com>
> ---
>  drivers/firmware/efi/stmm/tee_stmm_efi.c | 11 +++++------
>  1 file changed, 5 insertions(+), 6 deletions(-)

Reviewed-by: Sumit Garg <sumit.garg@oss.qualcomm.com>

-Sumit

> 
> diff --git a/drivers/firmware/efi/stmm/tee_stmm_efi.c b/drivers/firmware/efi/stmm/tee_stmm_efi.c
> index 5903811858b6..7b04dd649629 100644
> --- a/drivers/firmware/efi/stmm/tee_stmm_efi.c
> +++ b/drivers/firmware/efi/stmm/tee_stmm_efi.c
> @@ -520,8 +520,9 @@ static void tee_stmm_restore_efivars_generic_ops(void)
>  	efivars_generic_ops_register();
>  }
>  
> -static int tee_stmm_efi_probe(struct device *dev)
> +static int tee_stmm_efi_probe(struct tee_client_device *tee_dev)
>  {
> +	struct device *dev = &tee_dev->dev;
>  	struct tee_ioctl_open_session_arg sess_arg;
>  	efi_status_t ret;
>  	int rc;
> @@ -571,21 +572,19 @@ static int tee_stmm_efi_probe(struct device *dev)
>  	return 0;
>  }
>  
> -static int tee_stmm_efi_remove(struct device *dev)
> +static void tee_stmm_efi_remove(struct tee_client_device *dev)
>  {
>  	tee_stmm_restore_efivars_generic_ops();
> -
> -	return 0;
>  }
>  
>  MODULE_DEVICE_TABLE(tee, tee_stmm_efi_id_table);
>  
>  static struct tee_client_driver tee_stmm_efi_driver = {
>  	.id_table	= tee_stmm_efi_id_table,
> +	.probe		= tee_stmm_efi_probe,
> +	.remove		= tee_stmm_efi_remove,
>  	.driver		= {
>  		.name		= "tee-stmm-efi",
> -		.probe		= tee_stmm_efi_probe,
> -		.remove		= tee_stmm_efi_remove,
>  	},
>  };
>  
> -- 
> 2.47.3
> 
> 

Re: [PATCH v1 00/17] tee: Use bus callbacks instead of driver callbacks

[Uwe Kleine-König]

[-- Attachment #1: Type: text/plain, Size: 3035 bytes --]

Hello Sumit,

On Mon, Dec 15, 2025 at 04:54:11PM +0900, Sumit Garg wrote:
> On Thu, Dec 11, 2025 at 06:14:54PM +0100, Uwe Kleine-König wrote:
> > Hello,
> > 
> > the objective of this series is to make tee driver stop using callbacks
> > in struct device_driver. These were superseded by bus methods in 2006
> > (commit 594c8281f905 ("[PATCH] Add bus_type probe, remove, shutdown
> > methods.")) but nobody cared to convert all subsystems accordingly.
> > 
> > Here the tee drivers are converted. The first commit is somewhat
> > unrelated, but simplifies the conversion (and the drivers). It
> > introduces driver registration helpers that care about setting the bus
> > and owner. (The latter is missing in all drivers, so by using these
> > helpers the drivers become more correct.)
> > 
> > The patches #4 - #17 depend on the first two, so if they should be
> > applied to their respective subsystem trees these must contain the first
> > two patches first.
> 
> Thanks Uwe for your efforts to clean up the boilerplate code for TEE bus
> drivers.

Thanks for your feedback. I will prepare a v2 and address your comments
(whitespace issues and wrong callback in the shutdown method).

> > Note that after patch #2 is applied, unconverted drivers provoke a
> > warning in driver_register(), so it would be good for the user
> > experience if the whole series goes in during a single merge window.
> 
> +1
> 
> I suggest the whole series goes via the Jens tree since there shouldn't
> be any chances for conflict here.
> 
> > So
> > I guess an immutable branch containing the frist three patches that can
> > be merged into the other subsystem trees would be sensible.
> > 
> > After all patches are applied, tee_bus_type can be made private to
> > drivers/tee as it's not used in other places any more.
> > 
> 
> Feel free to make the tee_bus_type private as the last patch in the series
> such that any followup driver follows this clean approach.

There is a bit more to do for that than I'm willing to invest. With my
patch series applied `tee_bus_type` is still used in
drivers/tee/optee/device.c and drivers/tee/tee_core.c. Maybe it's
sensible to merge these two files into a single one.

The things I wonder about additionally are:

 - if CONFIG_OPTEE=n and CONFIG_TEE=y|m the tee bus is only used for
   drivers but not devices.

 - optee_register_device() calls device_create_file() on
   &optee_device->dev after device_register(&optee_device->dev).
   (Attention half-knowledge!) I think device_create_file() should not
   be called on an already registered device (or you have to send a
   uevent afterwards). This should probably use type attribute groups.
   (Or the need_supplicant attribute should be dropped as it isn't very
   useful. This would maybe be considered an ABI change however.)

 - Why does optee_probe() in drivers/tee/optee/smc_abi.c unregister all
   optee devices in its error path (optee_unregister_devices())?

Best regards
Uwe

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Re: [PATCH v1 06/17] rtc: optee: Migrate to use tee specific driver registration function

[Alexandre Belloni]

On 11/12/2025 18:15:00+0100, Uwe Kleine-König wrote:
> The tee subsystem recently got a set of dedicated functions to register
> (and unregister) a tee driver. Make use of them. These care for setting the
> driver's bus (so the explicit assignment can be dropped) and the driver
> owner (which is an improvement this driver benefits from).
> 
> Signed-off-by: Uwe Kleine-König <u.kleine-koenig@baylibre.com>

Acked-by: Alexandre Belloni <alexandre.belloni@bootlin.com>

> ---
>  drivers/rtc/rtc-optee.c | 14 +-------------
>  1 file changed, 1 insertion(+), 13 deletions(-)
> 
> diff --git a/drivers/rtc/rtc-optee.c b/drivers/rtc/rtc-optee.c
> index 184c6d142801..f924a729ead0 100644
> --- a/drivers/rtc/rtc-optee.c
> +++ b/drivers/rtc/rtc-optee.c
> @@ -726,25 +726,13 @@ static struct tee_client_driver optee_rtc_driver = {
>  	.id_table	= optee_rtc_id_table,
>  	.driver		= {
>  		.name		= "optee_rtc",
> -		.bus		= &tee_bus_type,
>  		.probe		= optee_rtc_probe,
>  		.remove		= optee_rtc_remove,
>  		.pm		= pm_sleep_ptr(&optee_rtc_pm_ops),
>  	},
>  };
>  
> -static int __init optee_rtc_mod_init(void)
> -{
> -	return driver_register(&optee_rtc_driver.driver);
> -}
> -
> -static void __exit optee_rtc_mod_exit(void)
> -{
> -	driver_unregister(&optee_rtc_driver.driver);
> -}
> -
> -module_init(optee_rtc_mod_init);
> -module_exit(optee_rtc_mod_exit);
> +module_tee_client_driver(optee_rtc_driver);
>  
>  MODULE_LICENSE("GPL v2");
>  MODULE_AUTHOR("Clément Léger <clement.leger@bootlin.com>");
> -- 
> 2.47.3
> 

-- 
Alexandre Belloni, co-owner and COO, Bootlin
Embedded Linux and Kernel engineering
https://bootlin.com

Re: [PATCH v1 07/17] rtc: optee: Make use of tee bus methods

[Alexandre Belloni]

On 11/12/2025 18:15:01+0100, Uwe Kleine-König wrote:
> The tee bus got dedicated callbacks for probe and remove. Make use of
> these. This fixes a runtime warning about the driver needing to be
> converted to the bus methods.
> 
> Signed-off-by: Uwe Kleine-König <u.kleine-koenig@baylibre.com>

Acked-by: Alexandre Belloni <alexandre.belloni@bootlin.com>

> ---
>  drivers/rtc/rtc-optee.c | 13 ++++++-------
>  1 file changed, 6 insertions(+), 7 deletions(-)
> 
> diff --git a/drivers/rtc/rtc-optee.c b/drivers/rtc/rtc-optee.c
> index f924a729ead0..eefde789d194 100644
> --- a/drivers/rtc/rtc-optee.c
> +++ b/drivers/rtc/rtc-optee.c
> @@ -547,9 +547,9 @@ static int optee_ctx_match(struct tee_ioctl_version_data *ver, const void *data)
>  		return 0;
>  }
>  
> -static int optee_rtc_probe(struct device *dev)
> +static int optee_rtc_probe(struct tee_client_device *rtc_device)
>  {
> -	struct tee_client_device *rtc_device = to_tee_client_device(dev);
> +	struct device *dev = &rtc_device->dev;
>  	struct tee_ioctl_open_session_arg sess2_arg = {0};
>  	struct tee_ioctl_open_session_arg sess_arg = {0};
>  	struct optee_rtc *priv;
> @@ -682,8 +682,9 @@ static int optee_rtc_probe(struct device *dev)
>  	return err;
>  }
>  
> -static int optee_rtc_remove(struct device *dev)
> +static void optee_rtc_remove(struct tee_client_device *rtc_device)
>  {
> +	struct device *dev = &rtc_device->dev;
>  	struct optee_rtc *priv = dev_get_drvdata(dev);
>  
>  	if (priv->features & TA_RTC_FEATURE_ALARM) {
> @@ -696,8 +697,6 @@ static int optee_rtc_remove(struct device *dev)
>  	tee_shm_free(priv->shm);
>  	tee_client_close_session(priv->ctx, priv->session_id);
>  	tee_client_close_context(priv->ctx);
> -
> -	return 0;
>  }
>  
>  static int optee_rtc_suspend(struct device *dev)
> @@ -724,10 +723,10 @@ MODULE_DEVICE_TABLE(tee, optee_rtc_id_table);
>  
>  static struct tee_client_driver optee_rtc_driver = {
>  	.id_table	= optee_rtc_id_table,
> +	.probe		= optee_rtc_probe,
> +	.remove		= optee_rtc_remove,
>  	.driver		= {
>  		.name		= "optee_rtc",
> -		.probe		= optee_rtc_probe,
> -		.remove		= optee_rtc_remove,
>  		.pm		= pm_sleep_ptr(&optee_rtc_pm_ops),
>  	},
>  };
> -- 
> 2.47.3
> 

-- 
Alexandre Belloni, co-owner and COO, Bootlin
Embedded Linux and Kernel engineering
https://bootlin.com

Re: [PATCH v1 00/17] tee: Use bus callbacks instead of driver callbacks

[Sumit Garg]

Hi Uwe,

On Mon, Dec 15, 2025 at 3:02 PM Uwe Kleine-König
<u.kleine-koenig@baylibre.com> wrote:
>
> Hello Sumit,
>
> On Mon, Dec 15, 2025 at 04:54:11PM +0900, Sumit Garg wrote:
> > On Thu, Dec 11, 2025 at 06:14:54PM +0100, Uwe Kleine-König wrote:
> > > Hello,
> > >
> > > the objective of this series is to make tee driver stop using callbacks
> > > in struct device_driver. These were superseded by bus methods in 2006
> > > (commit 594c8281f905 ("[PATCH] Add bus_type probe, remove, shutdown
> > > methods.")) but nobody cared to convert all subsystems accordingly.
> > >
> > > Here the tee drivers are converted. The first commit is somewhat
> > > unrelated, but simplifies the conversion (and the drivers). It
> > > introduces driver registration helpers that care about setting the bus
> > > and owner. (The latter is missing in all drivers, so by using these
> > > helpers the drivers become more correct.)
> > >
> > > The patches #4 - #17 depend on the first two, so if they should be
> > > applied to their respective subsystem trees these must contain the first
> > > two patches first.
> >
> > Thanks Uwe for your efforts to clean up the boilerplate code for TEE bus
> > drivers.
>
> Thanks for your feedback. I will prepare a v2 and address your comments
> (whitespace issues and wrong callback in the shutdown method).
>
> > > Note that after patch #2 is applied, unconverted drivers provoke a
> > > warning in driver_register(), so it would be good for the user
> > > experience if the whole series goes in during a single merge window.
> >
> > +1
> >
> > I suggest the whole series goes via the Jens tree since there shouldn't
> > be any chances for conflict here.
> >
> > > So
> > > I guess an immutable branch containing the frist three patches that can
> > > be merged into the other subsystem trees would be sensible.
> > >
> > > After all patches are applied, tee_bus_type can be made private to
> > > drivers/tee as it's not used in other places any more.
> > >
> >
> > Feel free to make the tee_bus_type private as the last patch in the series
> > such that any followup driver follows this clean approach.
>
> There is a bit more to do for that than I'm willing to invest. With my
> patch series applied `tee_bus_type` is still used in
> drivers/tee/optee/device.c and drivers/tee/tee_core.c.

Oh I see, I guess we need to come with some helpers around device
register/unregister from TEE subsystem as well. Let's plan that for a
followup patch-set, I don't want this patch-set to be bloated more.

> Maybe it's
> sensible to merge these two files into a single one.

It's not possible as the design for TEE bus is to have TEE
implementation drivers like OP-TEE, AMD-TEE, TS-TEE, QTEE and so on to
register devices on the bus.

>
> The things I wonder about additionally are:
>
>  - if CONFIG_OPTEE=n and CONFIG_TEE=y|m the tee bus is only used for
>    drivers but not devices.

Yeah since the devices are rather added by the TEE implementation driver.

>
>  - optee_register_device() calls device_create_file() on
>    &optee_device->dev after device_register(&optee_device->dev).
>    (Attention half-knowledge!) I think device_create_file() should not
>    be called on an already registered device (or you have to send a
>    uevent afterwards). This should probably use type attribute groups.
>    (Or the need_supplicant attribute should be dropped as it isn't very
>    useful. This would maybe be considered an ABI change however.)

The reasoning for this attribute should be explained by commit:
7269cba53d90 ("tee: optee: Fix supplicant based device enumeration").
In summary it's due to a weird dependency for devices we have with the
user-space daemon: tee-supplicant.

>
>  - Why does optee_probe() in drivers/tee/optee/smc_abi.c unregister all
>    optee devices in its error path (optee_unregister_devices())?

This is mostly to take care of if any device got registered before the
failure occured. Let me know if you have a better way to address that.

-Sumit

Re: [PATCH v1 00/17] tee: Use bus callbacks instead of driver callbacks

[Uwe Kleine-König]

[-- Attachment #1: Type: text/plain, Size: 2840 bytes --]

Hello,

On Tue, Dec 16, 2025 at 01:08:38PM +0530, Sumit Garg wrote:
> On Mon, Dec 15, 2025 at 3:02 PM Uwe Kleine-König
> <u.kleine-koenig@baylibre.com> wrote:
> > On Mon, Dec 15, 2025 at 04:54:11PM +0900, Sumit Garg wrote:
> > > Feel free to make the tee_bus_type private as the last patch in the series
> > > such that any followup driver follows this clean approach.
> >
> > There is a bit more to do for that than I'm willing to invest. With my
> > patch series applied `tee_bus_type` is still used in
> > drivers/tee/optee/device.c and drivers/tee/tee_core.c.
> 
> Oh I see, I guess we need to come with some helpers around device
> register/unregister from TEE subsystem as well. Let's plan that for a
> followup patch-set, I don't want this patch-set to be bloated more.

Don't consider me in for that. But it sounds like a nice addition.

> > Maybe it's
> > sensible to merge these two files into a single one.
> 
> It's not possible as the design for TEE bus is to have TEE
> implementation drivers like OP-TEE, AMD-TEE, TS-TEE, QTEE and so on to
> register devices on the bus.

So only OP-TEE uses the bus for devices and the other *-TEE don't. Also
sounds like something worth to be fixed.

> > The things I wonder about additionally are:
> >
> >  - if CONFIG_OPTEE=n and CONFIG_TEE=y|m the tee bus is only used for
> >    drivers but not devices.
> 
> Yeah since the devices are rather added by the TEE implementation driver.
> 
> >
> >  - optee_register_device() calls device_create_file() on
> >    &optee_device->dev after device_register(&optee_device->dev).
> >    (Attention half-knowledge!) I think device_create_file() should not
> >    be called on an already registered device (or you have to send a
> >    uevent afterwards). This should probably use type attribute groups.
> >    (Or the need_supplicant attribute should be dropped as it isn't very
> >    useful. This would maybe be considered an ABI change however.)
> 
> The reasoning for this attribute should be explained by commit:
> 7269cba53d90 ("tee: optee: Fix supplicant based device enumeration").
> In summary it's due to a weird dependency for devices we have with the
> user-space daemon: tee-supplicant.

From reading that once I don't understand it. (But no need to explain
:-)

Still the file should better be added before device_add() is called.

> >  - Why does optee_probe() in drivers/tee/optee/smc_abi.c unregister all
> >    optee devices in its error path (optee_unregister_devices())?
> 
> This is mostly to take care of if any device got registered before the
> failure occured. Let me know if you have a better way to address that.

Without understanding the tee stuff, I'd say: Don't bother and only undo
the things that probe did before the failure.

Best regards
Uwe

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Re: [PATCH v1 00/17] tee: Use bus callbacks instead of driver callbacks

[Sumit Garg]

On Tue, Dec 16, 2025 at 12:08:38PM +0100, Uwe Kleine-König wrote:
> Hello,
> 
> On Tue, Dec 16, 2025 at 01:08:38PM +0530, Sumit Garg wrote:
> > On Mon, Dec 15, 2025 at 3:02 PM Uwe Kleine-König
> > <u.kleine-koenig@baylibre.com> wrote:
> > > On Mon, Dec 15, 2025 at 04:54:11PM +0900, Sumit Garg wrote:
> > > > Feel free to make the tee_bus_type private as the last patch in the series
> > > > such that any followup driver follows this clean approach.
> > >
> > > There is a bit more to do for that than I'm willing to invest. With my
> > > patch series applied `tee_bus_type` is still used in
> > > drivers/tee/optee/device.c and drivers/tee/tee_core.c.
> > 
> > Oh I see, I guess we need to come with some helpers around device
> > register/unregister from TEE subsystem as well. Let's plan that for a
> > followup patch-set, I don't want this patch-set to be bloated more.
> 
> Don't consider me in for that. But it sounds like a nice addition.
>

No worries, the current cleanup is fine for now.

> > > Maybe it's
> > > sensible to merge these two files into a single one.
> > 
> > It's not possible as the design for TEE bus is to have TEE
> > implementation drivers like OP-TEE, AMD-TEE, TS-TEE, QTEE and so on to
> > register devices on the bus.
> 
> So only OP-TEE uses the bus for devices and the other *-TEE don't. Also
> sounds like something worth to be fixed.

The TEE bus is common for all the TEE implementation drivers which need
to support kernel TEE client drivers. I am aware there will be QTEE and
TS-TEE from past discussion that they will be exposing devices on the
TEE bus.

> 
> > > The things I wonder about additionally are:
> > >
> > >  - if CONFIG_OPTEE=n and CONFIG_TEE=y|m the tee bus is only used for
> > >    drivers but not devices.
> > 
> > Yeah since the devices are rather added by the TEE implementation driver.
> > 
> > >
> > >  - optee_register_device() calls device_create_file() on
> > >    &optee_device->dev after device_register(&optee_device->dev).
> > >    (Attention half-knowledge!) I think device_create_file() should not
> > >    be called on an already registered device (or you have to send a
> > >    uevent afterwards). This should probably use type attribute groups.
> > >    (Or the need_supplicant attribute should be dropped as it isn't very
> > >    useful. This would maybe be considered an ABI change however.)
> > 
> > The reasoning for this attribute should be explained by commit:
> > 7269cba53d90 ("tee: optee: Fix supplicant based device enumeration").
> > In summary it's due to a weird dependency for devices we have with the
> > user-space daemon: tee-supplicant.
> 
> From reading that once I don't understand it. (But no need to explain
> :-)
> 
> Still the file should better be added before device_add() is called.

Noted, let me see if I can get to fix this until someone jumps in before
me.

> 
> > >  - Why does optee_probe() in drivers/tee/optee/smc_abi.c unregister all
> > >    optee devices in its error path (optee_unregister_devices())?
> > 
> > This is mostly to take care of if any device got registered before the
> > failure occured. Let me know if you have a better way to address that.
> 
> Without understanding the tee stuff, I'd say: Don't bother and only undo
> the things that probe did before the failure.
> 

True, but this is special case where if there is any leftover device
registered from the TEE implementation then it is likely going to cause
the corresponding kernel client driver crash.

-Sumit

Re: [PATCH v1 00/17] tee: Use bus callbacks instead of driver callbacks

[Uwe Kleine-König]

[-- Attachment #1: Type: text/plain, Size: 1171 bytes --]

Hello Sumit,

On Wed, Dec 17, 2025 at 01:25:39PM +0530, Sumit Garg wrote:
> On Tue, Dec 16, 2025 at 12:08:38PM +0100, Uwe Kleine-König wrote:
> > On Tue, Dec 16, 2025 at 01:08:38PM +0530, Sumit Garg wrote:
> > > On Mon, Dec 15, 2025 at 3:02 PM Uwe Kleine-König
> > > <u.kleine-koenig@baylibre.com> wrote:
> > > >  - Why does optee_probe() in drivers/tee/optee/smc_abi.c unregister all
> > > >    optee devices in its error path (optee_unregister_devices())?
> > > 
> > > This is mostly to take care of if any device got registered before the
> > > failure occured. Let me know if you have a better way to address that.
> > 
> > Without understanding the tee stuff, I'd say: Don't bother and only undo
> > the things that probe did before the failure.
> 
> True, but this is special case where if there is any leftover device
> registered from the TEE implementation then it is likely going to cause
> the corresponding kernel client driver crash.

You are aware that this is racy? So if a driver crashes e.g. after
teedev_close_context() it might happen that it is registered just after
optee_unregister_devices() returns.

Best regards
Uwe

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Re: [PATCH v1 00/17] tee: Use bus callbacks instead of driver callbacks

[Sumit Garg]

On Wed, Dec 17, 2025 at 09:21:41AM +0100, Uwe Kleine-König wrote:
> Hello Sumit,
> 
> On Wed, Dec 17, 2025 at 01:25:39PM +0530, Sumit Garg wrote:
> > On Tue, Dec 16, 2025 at 12:08:38PM +0100, Uwe Kleine-König wrote:
> > > On Tue, Dec 16, 2025 at 01:08:38PM +0530, Sumit Garg wrote:
> > > > On Mon, Dec 15, 2025 at 3:02 PM Uwe Kleine-König
> > > > <u.kleine-koenig@baylibre.com> wrote:
> > > > >  - Why does optee_probe() in drivers/tee/optee/smc_abi.c unregister all
> > > > >    optee devices in its error path (optee_unregister_devices())?
> > > > 
> > > > This is mostly to take care of if any device got registered before the
> > > > failure occured. Let me know if you have a better way to address that.
> > > 
> > > Without understanding the tee stuff, I'd say: Don't bother and only undo
> > > the things that probe did before the failure.
> > 
> > True, but this is special case where if there is any leftover device
> > registered from the TEE implementation then it is likely going to cause
> > the corresponding kernel client driver crash.
> 
> You are aware that this is racy? So if a driver crashes e.g. after
> teedev_close_context() it might happen that it is registered just after
> optee_unregister_devices() returns.
> 

I see your point about the unavoidable race. Maybe it's better to not
try anything and let the kernel client driver fail.

-Sumit