@@ -5,6 +5,7 @@ config DRM_VKMS
depends on DRM && MMU
select DRM_KMS_HELPER
select DRM_GEM_SHMEM_HELPER
+ select CONFIGFS_FS
select CRC32
default n
help
@@ -1,5 +1,6 @@
# SPDX-License-Identifier: GPL-2.0-only
vkms-y := \
+ vkms_configfs.o \
vkms_drv.o \
vkms_plane.o \
vkms_output.o \
new file mode 100644
@@ -0,0 +1,144 @@
+// SPDX-License-Identifier: GPL-2.0+
+
+#include <linux/configfs.h>
+#include <linux/mutex.h>
+#include <drm/drm_print.h>
+#include <linux/platform_device.h>
+#include <linux/slab.h>
+
+#include "vkms_configfs.h"
+#include "vkms_drv.h"
+#include "vkms_config.h"
+
+static ssize_t device_enable_show(struct config_item *item, char *page)
+{
+ return sprintf(page, "%d\n",
+ config_item_to_vkms_configfs_device(item)->enabled);
+}
+
+static ssize_t device_enable_store(struct config_item *item,
+ const char *page, size_t count)
+{
+ struct vkms_configfs_device *vkms_configfs_device =
+ config_item_to_vkms_configfs_device(item);
+
+ bool value;
+ int ret;
+
+ ret = kstrtobool(page, &value);
+ if (ret)
+ return -EINVAL;
+
+ mutex_lock(&vkms_configfs_device->lock);
+
+ vkms_configfs_device->enabled = value;
+
+ if (value)
+ vkms_create(vkms_configfs_device->vkms_config);
+ else
+ vkms_destroy(vkms_configfs_device->vkms_config);
+
+ mutex_unlock(&vkms_configfs_device->lock);
+
+ return (ssize_t)count;
+}
+
+CONFIGFS_ATTR(device_, enable);
+
+static struct configfs_attribute *device_attrs[] = {
+ &device_attr_enable,
+ NULL,
+};
+
+static void device_release(struct config_item *item)
+{
+ struct vkms_configfs_device *vkms_configfs_device =
+ config_item_to_vkms_configfs_device(item);
+
+ mutex_destroy(&vkms_configfs_device->lock);
+ vkms_config_destroy(vkms_configfs_device->vkms_config);
+
+ kfree(vkms_configfs_device);
+}
+
+static struct configfs_item_operations device_item_operations = {
+ .release = &device_release,
+};
+
+static const struct config_item_type device_item_type = {
+ .ct_attrs = device_attrs,
+ .ct_item_ops = &device_item_operations,
+ .ct_owner = THIS_MODULE,
+};
+
+/* Top directory management. Each new directory here is a new device */
+static struct config_group *root_make_group(struct config_group *group,
+ const char *name)
+{
+ struct vkms_config_plane *plane;
+ struct vkms_config_crtc *crtc;
+ struct vkms_config_encoder *encoder;
+ struct vkms_configfs_device *configfs = kzalloc(sizeof(*configfs), GFP_KERNEL);
+
+ if (!configfs)
+ return ERR_PTR(-ENOMEM);
+
+ mutex_init(&configfs->lock);
+
+ configfs->vkms_config = vkms_config_create();
+
+ if (!configfs->vkms_config) {
+ kfree(configfs);
+ return ERR_PTR(-ENOMEM);
+ }
+
+ plane = vkms_config_create_plane(configfs->vkms_config);
+ crtc = vkms_config_create_crtc(configfs->vkms_config);
+ encoder = vkms_config_create_encoder(configfs->vkms_config);
+
+ if (!plane || !crtc || !encoder ||
+ vkms_config_plane_attach_crtc(plane, crtc) ||
+ vkms_config_encoder_attach_crtc(encoder, crtc)) {
+ vkms_config_destroy(configfs->vkms_config);
+ kfree(configfs);
+ return ERR_PTR(-ENOMEM);
+ }
+
+ plane->type = DRM_PLANE_TYPE_PRIMARY;
+
+ config_group_init_type_name(&configfs->group, name,
+ &device_item_type);
+
+ return &configfs->group;
+}
+
+static struct configfs_group_operations root_group_operations = {
+ .make_group = &root_make_group,
+};
+
+static struct config_item_type root_item_type = {
+ .ct_group_ops = &root_group_operations,
+ .ct_owner = THIS_MODULE,
+};
+
+static struct configfs_subsystem vkms_subsys = {
+ .su_group = {
+ .cg_item = {
+ .ci_name = "vkms",
+ .ci_type = &root_item_type,
+ },
+ },
+ .su_mutex = __MUTEX_INITIALIZER(vkms_subsys.su_mutex),
+};
+
+int vkms_init_configfs(void)
+{
+ config_group_init(&vkms_subsys.su_group);
+
+ return configfs_register_subsystem(&vkms_subsys);
+}
+
+void vkms_unregister_configfs(void)
+{
+ configfs_unregister_subsystem(&vkms_subsys);
+}
new file mode 100644
@@ -0,0 +1,35 @@
+/* SPDX-License-Identifier: GPL-2.0+ */
+
+#include <linux/configfs.h>
+#include <linux/mutex.h>
+
+#ifndef _VKMS_CONFIGFS_H
+#define _VKMS_CONFIGFS_H
+
+/**
+ * struct vkms_configfs_device - Internal object to manage all the configfs items related to one
+ * device
+ *
+ * @group: Main configfs group for a device
+ * @platform_device: If a device was created (@enabled = true), stores a pointer to it
+ * @lock: Mutex used to avoid conflicting edition of @vkms_config
+ * @enabled: Store if the device was created or not
+ * @vkms_config: Current vkms configuration
+ */
+struct vkms_configfs_device {
+ struct config_group group;
+
+ struct mutex lock;
+ bool enabled;
+
+ struct vkms_config *vkms_config;
+};
+
+#define config_item_to_vkms_configfs_device(item) \
+ container_of(to_config_group((item)), struct vkms_configfs_device, group)
+
+/* ConfigFS Support */
+int vkms_init_configfs(void);
+void vkms_unregister_configfs(void);
+
+#endif /* _VKMS_CONFIGFS_H */
@@ -29,6 +29,7 @@
#include "vkms_drv.h"
#include "vkms_crtc.h"
#include "vkms_config.h"
+#include "vkms_configfs.h"
#include <drm/drm_print.h>
#include <drm/drm_debugfs.h>
@@ -270,7 +271,7 @@ int vkms_create(struct vkms_config *config)
struct platform_device *pdev;
struct vkms_device *vkms_device;
- pdev = platform_device_register_simple(DRIVER_NAME, -1, NULL, 0);
+ pdev = platform_device_register_simple(DRIVER_NAME, PLATFORM_DEVID_AUTO, NULL, 0);
if (IS_ERR(pdev))
return PTR_ERR(pdev);
@@ -324,9 +325,17 @@ static int __init vkms_init(void)
if (IS_ERR(default_config))
return PTR_ERR(default_config);
+ ret = vkms_init_configfs();
+ if (ret) {
+ DRM_ERROR("Unable to initialize configfs\n");
+ vkms_config_destroy(default_config);
+ }
+
ret = vkms_create(default_config);
- if (ret)
+ if (ret) {
+ vkms_unregister_configfs();
vkms_config_destroy(default_config);
+ }
return ret;
}
@@ -355,6 +364,8 @@ static void __exit vkms_exit(void)
vkms_destroy(default_config);
vkms_config_destroy(default_config);
+
+ vkms_unregister_configfs();
}
module_init(vkms_init);
VKMS is manly used to test userspace program and its behavior. The current implementation is not very configurable as you can only have one device, with few specific planes. This is the introduction of a basic interface to dynamically create new devices. The new interface is: /config/vkms DEVICE_1 ┗━ enable DEVICE_2 ┗━ enable Signed-off-by: Louis Chauvet <louis.chauvet@bootlin.com> --- drivers/gpu/drm/vkms/Kconfig | 1 + drivers/gpu/drm/vkms/Makefile | 1 + drivers/gpu/drm/vkms/vkms_configfs.c | 144 +++++++++++++++++++++++++++++++++++ drivers/gpu/drm/vkms/vkms_configfs.h | 35 +++++++++ drivers/gpu/drm/vkms/vkms_drv.c | 15 +++- 5 files changed, 194 insertions(+), 2 deletions(-)