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

Uwe Kleine-König
2025-12-11T17:15:57Z

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