tee: add bus driver framework for TEE based devices

Introduce a generic TEE bus driver concept for TEE based kernel drivers
which would like to communicate with TEE based devices/services. Also
add support in module device table for these new TEE based devices.

In this TEE bus concept, devices/services are identified via Universally
Unique Identifier (UUID) and drivers register a table of device UUIDs
which they can support.

So this TEE bus framework registers following apis:
- match(): Iterates over the driver UUID table to find a corresponding
  match for device UUID. If a match is found, then this particular device
  is probed via corresponding probe api registered by the driver. This
  process happens whenever a device or a driver is registered with TEE
  bus.
- uevent(): Notifies user-space (udev) whenever a new device is registered
  on this bus for auto-loading of modularized drivers.

Also this framework allows for device enumeration to be specific to
corresponding TEE implementation like OP-TEE etc.

Signed-off-by: Sumit Garg <sumit.garg@linaro.org>
Reviewed-by: Daniel Thompson <daniel.thompson@linaro.org>
Reviewed-by: Bhupesh Sharma <bhsharma@redhat.com>
Signed-off-by: Jens Wiklander <jens.wiklander@linaro.org>

2 files changed, 22 insertions, 0 deletions

diff --git a/scripts/mod/devicetable-offsets.c b/scripts/mod/devicetable-offsets.c
index 293004499b4d..160718383a71 100644
--- a/scripts/mod/devicetable-offsets.c
+++ b/scripts/mod/devicetable-offsets.c
@@ -225,5 +225,8 @@ int main(void)
 	DEVID_FIELD(typec_device_id, svid);
 	DEVID_FIELD(typec_device_id, mode);
 
+	DEVID(tee_client_device_id);
+	DEVID_FIELD(tee_client_device_id, uuid);
+
 	return 0;
 }
diff --git a/scripts/mod/file2alias.c b/scripts/mod/file2alias.c
index a37af7d71973..d0e41723627f 100644
--- a/scripts/mod/file2alias.c
+++ b/scripts/mod/file2alias.c
@@ -37,6 +37,9 @@ typedef unsigned char	__u8;
 typedef struct {
 	__u8 b[16];
 } uuid_le;
+typedef struct {
+	__u8 b[16];
+} uuid_t;
 
 /* Big exception to the "don't include kernel headers into userspace, which
  * even potentially has different endianness and word sizes, since
@@ -1287,6 +1290,21 @@ static int do_typec_entry(const char *filename, void *symval, char *alias)
 	return 1;
 }
 
+/* Looks like: tee:uuid */
+static int do_tee_entry(const char *filename, void *symval, char *alias)
+{
+	DEF_FIELD(symval, tee_client_device_id, uuid);
+
+	sprintf(alias, "tee:%02x%02x%02x%02x-%02x%02x-%02x%02x-%02x%02x-%02x%02x%02x%02x%02x%02x",
+		uuid.b[0], uuid.b[1], uuid.b[2], uuid.b[3], uuid.b[4],
+		uuid.b[5], uuid.b[6], uuid.b[7], uuid.b[8], uuid.b[9],
+		uuid.b[10], uuid.b[11], uuid.b[12], uuid.b[13], uuid.b[14],
+		uuid.b[15]);
+
+	add_wildcard(alias);
+	return 1;
+}
+
 /* Does namelen bytes of name exactly match the symbol? */
 static bool sym_is(const char *name, unsigned namelen, const char *symbol)
 {
@@ -1357,6 +1375,7 @@ static const struct devtable devtable[] = {
 	{"fslmc", SIZE_fsl_mc_device_id, do_fsl_mc_entry},
 	{"tbsvc", SIZE_tb_service_id, do_tbsvc_entry},
 	{"typec", SIZE_typec_device_id, do_typec_entry},
+	{"tee", SIZE_tee_client_device_id, do_tee_entry},
 };
 
 /* Create MODULE_ALIAS() statements.