[RFC,v3,10/14] drm/vkms: Introduce configfs for device name

Commit Message

Louis Chauvet Jan. 21, 2025, 2:34 p.m. UTC

To allows the userspace to identify the device once it is enabled, create
a file to fetch it.

This file can only be read once the device is enabled, and will return the
device name, which can later be used to use it.

Signed-off-by: Louis Chauvet <[e-mail]>
---
 drivers/gpu/drm/vkms/vkms_configfs.c | 16 ++++++++++++++++
 1 file changed, 16 insertions(+)

Patch

diff --git a/drivers/gpu/drm/vkms/vkms_configfs.c b/drivers/gpu/drm/vkms/vkms_configfs.c
index eeb0c1e1b225f2a1a35ac6deb9457b90ba6542e5..d0bc6adfdae85b82ca043d318f84fca70840526c 100644
--- a/drivers/gpu/drm/vkms/vkms_configfs.c
+++ b/drivers/gpu/drm/vkms/vkms_configfs.c
@@ -927,10 +927,26 @@  static ssize_t device_enable_store(struct config_item *item,
 	return (ssize_t)count;
 }
 
+static ssize_t device_device_name_show(struct config_item *item, char *page)
+{
+	struct vkms_configfs_device *configfs_device = config_item_to_vkms_configfs_device(item);
+
+	scoped_guard(mutex, &configfs_device->lock)
+	{
+		if (configfs_device->enabled)
+			return sprintf(page, "%s\n",
+				       dev_name(configfs_device->vkms_config->dev->drm.dev));
+		return -EINVAL;
+	}
+	return -EINVAL;
+}
+
 CONFIGFS_ATTR(device_, enable);
+CONFIGFS_ATTR_RO(device_, device_name);
 
 static struct configfs_attribute *device_attrs[] = {
 	&device_attr_enable,
+	&device_attr_device_name,
 	NULL,
 };