Re: [PATCH v6 1/2] tee: add revision sysfs attribute

On Thu, Jan 8, 2026 at 7:45 AM Aristo Chen jj251510319013@gmail.com wrote:

Add a generic TEE revision sysfs attribute backed by a new optional get_tee_revision() callback. The revision string is diagnostic-only and must not be used to infer feature support.

Signed-off-by: Aristo Chen aristo.chen@canonical.com

Documentation/ABI/testing/sysfs-class-tee | 10 +++++ drivers/tee/tee_core.c | 51 ++++++++++++++++++++++- include/linux/tee_core.h | 9 ++++ 3 files changed, 69 insertions(+), 1 deletion(-)

checkpatch complains with:

WARNING: From:/Signed-off-by: email address mismatch: 'From: Aristo Chen jj251510319013@gmail.com' != 'Signed-off-by: Aristo Chen aristo.chen@canonical.com'

total: 0 errors, 1 warnings, 0 checks, 100 lines checked

Cheers, Jens

diff --git a/Documentation/ABI/testing/sysfs-class-tee b/Documentation/ABI/testing/sysfs-class-tee index c9144d16003e..1a0a3050aaa9 100644 --- a/Documentation/ABI/testing/sysfs-class-tee +++ b/Documentation/ABI/testing/sysfs-class-tee @@ -13,3 +13,13 @@ Description: space if the variable is absent. The primary purpose of this variable is to let systemd know whether tee-supplicant is needed in the early boot with initramfs.

+What: /sys/class/tee/tee{,priv}X/revision +Date: Jan 2026 +KernelVersion: 6.19 +Contact: op-tee@lists.trustedfirmware.org +Description:

•           Read-only revision string reported by the TEE driver. This is
  

•           for diagnostics only and must not be used to infer feature
  

•           support. Use TEE_IOC_VERSION for capability and compatibility
  

•           checks.
  

diff --git a/drivers/tee/tee_core.c b/drivers/tee/tee_core.c index d65d47cc154e..0a00499811c1 100644 --- a/drivers/tee/tee_core.c +++ b/drivers/tee/tee_core.c @@ -1146,7 +1146,56 @@ static struct attribute *tee_dev_attrs[] = { NULL };

-ATTRIBUTE_GROUPS(tee_dev); +static const struct attribute_group tee_dev_group = {

•   .attrs = tee_dev_attrs,
  

+};

+static ssize_t revision_show(struct device *dev,

•                        struct device_attribute *attr, char *buf)
  

+{

•   struct tee_device *teedev = container_of(dev, struct tee_device, dev);
  

•   char version[TEE_REVISION_STR_SIZE];
  

•   int ret;
  

•   if (!teedev->desc->ops->get_tee_revision)
  

•           return -ENODEV;
  

•   ret = teedev->desc->ops->get_tee_revision(teedev, version,
  

•                                             sizeof(version));
  

•   if (ret)
  

•           return ret;
  

•   return sysfs_emit(buf, "%s\n", version);
  

+} +static DEVICE_ATTR_RO(revision);

+static struct attribute *tee_revision_attrs[] = {

•   &dev_attr_revision.attr,
  

•   NULL
  

+};

+static umode_t tee_revision_attr_is_visible(struct kobject *kobj,

•                                       struct attribute *attr, int n)
  

+{

•   struct device *dev = kobj_to_dev(kobj);
  

•   struct tee_device *teedev = container_of(dev, struct tee_device, dev);
  

•   if (teedev->desc->ops->get_tee_revision)
  

•           return attr->mode;
  

•   return 0;
  

+}

+static const struct attribute_group tee_revision_group = {

•   .attrs = tee_revision_attrs,
  

•   .is_visible = tee_revision_attr_is_visible,
  

+};

+static const struct attribute_group *tee_dev_groups[] = {

•   &tee_dev_group,
  

•   &tee_revision_group,
  

•   NULL
  

+};

static const struct class tee_class = { .name = "tee", diff --git a/include/linux/tee_core.h b/include/linux/tee_core.h index 1f3e5dad6d0d..ee5f0bd41f43 100644 --- a/include/linux/tee_core.h +++ b/include/linux/tee_core.h @@ -76,6 +76,9 @@ struct tee_device { /**

• struct tee_driver_ops - driver operations vtable
• @get_version: returns version of driver

• • @get_tee_revision: returns revision string (diagnostic only);

• •                 do not infer feature support from this, use
    

• •                 TEE_IOC_VERSION instead
    

  • @open: called for a context when the device file is opened
  • @close_context: called when the device file is closed
  • @release: called to release the context

@@ -95,9 +98,12 @@ struct tee_device {

• client closes the device file, even if there are existing references to the
• context. The TEE driver can use @close_context to start cleaning up.

*/

struct tee_driver_ops { void (*get_version)(struct tee_device *teedev, struct tee_ioctl_version_data *vers);

•   int (*get_tee_revision)(struct tee_device *teedev,
  

•                           char *buf, size_t len);
    int (*open)(struct tee_context *ctx);
    void (*close_context)(struct tee_context *ctx);
    void (*release)(struct tee_context *ctx);
  

@@ -123,6 +129,9 @@ struct tee_driver_ops { int (*shm_unregister)(struct tee_context *ctx, struct tee_shm *shm); };

+/* Size for TEE revision string buffer used by get_tee_revision(). */ +#define TEE_REVISION_STR_SIZE 128

/**

• struct tee_desc - Describes the TEE driver to the subsystem
• @name: name of driver

-- 2.43.0