On Thu, 24 Jan 2019 at 15:15, Daniel Thompson daniel.thompson@linaro.org wrote:
On Thu, Jan 24, 2019 at 11:24:36AM +0530, Sumit Garg wrote:
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 out-of-tree drivers.
out-of-tree? Surely it can be used to auto-load any modulized driver.
Agree, will correct.
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
drivers/tee/tee_core.c | 57 ++++++++++++++++++++++++++++++++++++--- include/linux/mod_devicetable.h | 9 +++++++ include/linux/tee_drv.h | 32 +++++++++++++++++++++- scripts/mod/devicetable-offsets.c | 3 +++ scripts/mod/file2alias.c | 19 +++++++++++++ 5 files changed, 115 insertions(+), 5 deletions(-)
diff --git a/drivers/tee/tee_core.c b/drivers/tee/tee_core.c index 7b2bb4c..9f4c8bc 100644 --- a/drivers/tee/tee_core.c +++ b/drivers/tee/tee_core.c @@ -15,7 +15,6 @@ #define pr_fmt(fmt) "%s: " fmt, __func__
#include <linux/cdev.h> -#include <linux/device.h> #include <linux/fs.h> #include <linux/idr.h> #include <linux/module.h> @@ -1027,6 +1026,42 @@ int tee_client_invoke_func(struct tee_context *ctx, } EXPORT_SYMBOL_GPL(tee_client_invoke_func);
+static int tee_client_device_match(struct device *dev,
struct device_driver *drv)+{
const struct tee_client_device_id *id_table;struct tee_client_device *tee_device;id_table = to_tee_client_driver(drv)->id_table;tee_device = to_tee_client_device(dev);while (!uuid_is_null(&id_table->uuid)) {if (uuid_equal(&tee_device->id.uuid, &id_table->uuid))return 1;id_table++;}return 0;+}
+static int tee_client_device_uevent(struct device *dev,
struct kobj_uevent_env *env)+{
uuid_t *dev_id = &to_tee_client_device(dev)->id.uuid;if (add_uevent_var(env, "MODALIAS=tee:%pUb", dev_id))return -ENOMEM;return 0;Can just return directly here:
return add_uevent_var(... )
Okay will use this instead.
Other than these nitpicks then FWIW: Reviewed-by: Daniel Thompson daniel.thompson@linaro.org
Thanks. -Sumit
+}
+struct bus_type tee_bus_type = {
.name = "tee",.match = tee_client_device_match,.uevent = tee_client_device_uevent,+}; +EXPORT_SYMBOL_GPL(tee_bus_type);
static int __init tee_init(void) { int rc; @@ -1040,18 +1075,32 @@ static int __init tee_init(void) rc = alloc_chrdev_region(&tee_devt, 0, TEE_NUM_DEVICES, "tee"); if (rc) { pr_err("failed to allocate char dev region\n");
class_destroy(tee_class);tee_class = NULL;
goto out_unreg_class; }rc = bus_register(&tee_bus_type);if (rc) {pr_err("failed to register tee bus\n");goto out_unreg_chrdev;}return 0;+out_unreg_chrdev:
unregister_chrdev_region(tee_devt, TEE_NUM_DEVICES);+out_unreg_class:
class_destroy(tee_class);tee_class = NULL;return rc;}
static void __exit tee_exit(void) {
bus_unregister(&tee_bus_type);unregister_chrdev_region(tee_devt, TEE_NUM_DEVICES); class_destroy(tee_class); tee_class = NULL;
unregister_chrdev_region(tee_devt, TEE_NUM_DEVICES);}
subsys_initcall(tee_init); diff --git a/include/linux/mod_devicetable.h b/include/linux/mod_devicetable.h index f9bd2f3..14eaeeb 100644 --- a/include/linux/mod_devicetable.h +++ b/include/linux/mod_devicetable.h @@ -779,4 +779,13 @@ struct typec_device_id { kernel_ulong_t driver_data; };
+/**
- struct tee_client_device_id - tee based device identifier
- @uuid: For TEE based client devices we use the device uuid as
the identifier.- */
+struct tee_client_device_id {
uuid_t uuid;+};
#endif /* LINUX_MOD_DEVICETABLE_H */ diff --git a/include/linux/tee_drv.h b/include/linux/tee_drv.h index 6cfe058..ce957ce 100644 --- a/include/linux/tee_drv.h +++ b/include/linux/tee_drv.h @@ -15,11 +15,14 @@ #ifndef __TEE_DRV_H #define __TEE_DRV_H
-#include <linux/types.h> +#include <linux/device.h> #include <linux/idr.h> #include <linux/kref.h> #include <linux/list.h> +#include <linux/mod_devicetable.h> #include <linux/tee.h> +#include <linux/types.h> +#include <linux/uuid.h>
/*
- The file describes the API provided by the generic TEE driver to the
@@ -538,4 +541,31 @@ static inline bool tee_param_is_memref(struct tee_param *param) } }
+extern struct bus_type tee_bus_type;
+/**
- struct tee_client_device - tee based device
- @id: device identifier
- @dev: device structure
- */
+struct tee_client_device {
struct tee_client_device_id id;struct device dev;+};
+#define to_tee_client_device(d) container_of(d, struct tee_client_device, dev)
+/**
- struct tee_client_driver - tee client driver
- @id_table: device id table supported by this driver
- @driver: driver structure
- */
+struct tee_client_driver {
const struct tee_client_device_id *id_table;struct device_driver driver;+};
+#define to_tee_client_driver(d) \
container_of(d, struct tee_client_driver, driver)#endif /*__TEE_DRV_H*/ diff --git a/scripts/mod/devicetable-offsets.c b/scripts/mod/devicetable-offsets.c index 2930044..1607183 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 a37af7d..d0e4172 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.
2.7.4