diff mbox series

[v5,1/4] tee: add bus driver framework for TEE based devices

Message ID 1548309279-5281-2-git-send-email-sumit.garg@linaro.org (mailing list archive)
State New, archived
Headers show
Series Introduce TEE bus driver framework | expand

Commit Message

Sumit Garg Jan. 24, 2019, 5:54 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. 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.

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(-)

Comments

Daniel Thompson Jan. 24, 2019, 9:45 a.m. UTC | #1
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.


> 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(... )

Other than these nitpicks then FWIW:
Reviewed-by: Daniel Thompson <daniel.thompson@linaro.org>

> +}
> +
> +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
>
Sumit Garg Jan. 24, 2019, 10:19 a.m. UTC | #2
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
> >
Bhupesh Sharma Jan. 24, 2019, 10:49 a.m. UTC | #3
On Thu, Jan 24, 2019 at 3:49 PM Sumit Garg <sumit.garg@linaro.org> wrote:
>
> 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
> > >

With Daniel's inputs addressed, for this patch:
Reviewed-by: Bhupesh Sharma <bhsharma@redhat.com>

Thanks
diff mbox series

Patch

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;
+}
+
+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.