diff mbox series

[v4,1/4] tee: add bus driver framework for TEE based devices

Message ID 1548062959-31860-2-git-send-email-sumit.garg@linaro.org
State New
Headers show
Series [v4,1/4] tee: add bus driver framework for TEE based devices | expand

Commit Message

Sumit Garg Jan. 21, 2019, 9:29 a.m. UTC
Introduce a generic TEE bus driver concept for TEE based kernel drivers
which would like to communicate with TEE based devices/services.

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 a match() callback function which
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.

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  | 45 +++++++++++++++++++++++++++++++++++++++++----
 include/linux/tee_drv.h | 37 ++++++++++++++++++++++++++++++++++++-
 2 files changed, 77 insertions(+), 5 deletions(-)

-- 
2.7.4

Comments

Bhupesh Sharma Jan. 21, 2019, 3:28 p.m. UTC | #1
Hi Sumit,

On Mon, Jan 21, 2019 at 3:00 PM Sumit Garg <sumit.garg@linaro.org> wrote:
>

> Introduce a generic TEE bus driver concept for TEE based kernel drivers

> which would like to communicate with TEE based devices/services.

>

> 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 a match() callback function which

> 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.

>

> 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  | 45 +++++++++++++++++++++++++++++++++++++++++----

>  include/linux/tee_drv.h | 37 ++++++++++++++++++++++++++++++++++++-

>  2 files changed, 77 insertions(+), 5 deletions(-)

>

> diff --git a/drivers/tee/tee_core.c b/drivers/tee/tee_core.c

> index 7b2bb4c..55370d5 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 +1026,30 @@ 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 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)) {

> +               if (uuid_equal(&tee_device->id, id_table))

> +                       return 1;

> +               id_table++;

> +       }

> +

> +       return 0;

> +}

> +

> +struct bus_type tee_bus_type = {

> +       .name           = "tee",

> +       .match          = tee_client_device_match,

> +};

> +EXPORT_SYMBOL_GPL(tee_bus_type);

> +

>  static int __init tee_init(void)

>  {

>         int rc;

> @@ -1040,18 +1063,32 @@ 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/tee_drv.h b/include/linux/tee_drv.h

> index 6cfe058..ba985d8 100644

> --- a/include/linux/tee_drv.h

> +++ b/include/linux/tee_drv.h

> @@ -15,11 +15,13 @@

>  #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/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 +540,37 @@ static inline bool tee_param_is_memref(struct tee_param *param)

>         }

>  }

>

> +extern struct bus_type tee_bus_type;

> +

> +/*

> + * For TEE based client devices we use the device uuid as the

> + * identifier.

> + */

> +typedef uuid_t tee_client_device_id;

> +

> +/**

> + * struct tee_client_device - tee based device

> + * @id:                        device identifier

> + * @dev:               device structure

> + */

> +struct tee_client_device {

> +       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 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*/

> --

> 2.7.4

>


LGTM, if there are no further comments on this patch please free to add:
Reviewed-by: Bhupesh Sharma <bhsharma@redhat.com>


Thanks.
Sumit Garg Jan. 22, 2019, 1:33 p.m. UTC | #2
On Mon, 21 Jan 2019 at 20:58, Bhupesh Sharma <bhsharma@redhat.com> wrote:
>

> Hi Sumit,

>

> On Mon, Jan 21, 2019 at 3:00 PM Sumit Garg <sumit.garg@linaro.org> wrote:

> >

> > Introduce a generic TEE bus driver concept for TEE based kernel drivers

> > which would like to communicate with TEE based devices/services.

> >

> > 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 a match() callback function which

> > 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.

> >

> > 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  | 45 +++++++++++++++++++++++++++++++++++++++++----

> >  include/linux/tee_drv.h | 37 ++++++++++++++++++++++++++++++++++++-

> >  2 files changed, 77 insertions(+), 5 deletions(-)

> >

> > diff --git a/drivers/tee/tee_core.c b/drivers/tee/tee_core.c

> > index 7b2bb4c..55370d5 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 +1026,30 @@ 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 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)) {

> > +               if (uuid_equal(&tee_device->id, id_table))

> > +                       return 1;

> > +               id_table++;

> > +       }

> > +

> > +       return 0;

> > +}

> > +

> > +struct bus_type tee_bus_type = {

> > +       .name           = "tee",

> > +       .match          = tee_client_device_match,

> > +};

> > +EXPORT_SYMBOL_GPL(tee_bus_type);

> > +

> >  static int __init tee_init(void)

> >  {

> >         int rc;

> > @@ -1040,18 +1063,32 @@ 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/tee_drv.h b/include/linux/tee_drv.h

> > index 6cfe058..ba985d8 100644

> > --- a/include/linux/tee_drv.h

> > +++ b/include/linux/tee_drv.h

> > @@ -15,11 +15,13 @@

> >  #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/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 +540,37 @@ static inline bool tee_param_is_memref(struct tee_param *param)

> >         }

> >  }

> >

> > +extern struct bus_type tee_bus_type;

> > +

> > +/*

> > + * For TEE based client devices we use the device uuid as the

> > + * identifier.

> > + */

> > +typedef uuid_t tee_client_device_id;

> > +

> > +/**

> > + * struct tee_client_device - tee based device

> > + * @id:                        device identifier

> > + * @dev:               device structure

> > + */

> > +struct tee_client_device {

> > +       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 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*/

> > --

> > 2.7.4

> >

>

> LGTM, if there are no further comments on this patch please free to add:

> Reviewed-by: Bhupesh Sharma <bhsharma@redhat.com>

>


Thanks for this review tag. Actually I have to add support in module
device table for TEE bus devices as per Ard's comments on patch #4. So
that will require changes in this patch in next version.

-Sumit

> Thanks.
diff mbox series

Patch

diff --git a/drivers/tee/tee_core.c b/drivers/tee/tee_core.c
index 7b2bb4c..55370d5 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 +1026,30 @@  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 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)) {
+		if (uuid_equal(&tee_device->id, id_table))
+			return 1;
+		id_table++;
+	}
+
+	return 0;
+}
+
+struct bus_type tee_bus_type = {
+	.name		= "tee",
+	.match		= tee_client_device_match,
+};
+EXPORT_SYMBOL_GPL(tee_bus_type);
+
 static int __init tee_init(void)
 {
 	int rc;
@@ -1040,18 +1063,32 @@  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/tee_drv.h b/include/linux/tee_drv.h
index 6cfe058..ba985d8 100644
--- a/include/linux/tee_drv.h
+++ b/include/linux/tee_drv.h
@@ -15,11 +15,13 @@ 
 #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/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 +540,37 @@  static inline bool tee_param_is_memref(struct tee_param *param)
 	}
 }
 
+extern struct bus_type tee_bus_type;
+
+/*
+ * For TEE based client devices we use the device uuid as the
+ * identifier.
+ */
+typedef uuid_t tee_client_device_id;
+
+/**
+ * struct tee_client_device - tee based device
+ * @id:			device identifier
+ * @dev:		device structure
+ */
+struct tee_client_device {
+	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 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*/