drm/ttm: Add a virtual ttm sysfs device.

The device directory will be the base directory of the
sysfs representation of other ttm subsystems.

Signed-off-by: Thomas Hellstrom <thellstrom@vmware.com>
Signed-off-by: Dave Airlie <airlied@linux.ie>

1 files changed, 57 insertions, 1 deletions

diff --git a/drivers/gpu/drm/ttm/ttm_module.c b/drivers/gpu/drm/ttm/ttm_module.c
index 59ce8191d584..9a6edbfeaa9e 100644
--- a/drivers/gpu/drm/ttm/ttm_module.c
+++ b/drivers/gpu/drm/ttm/ttm_module.c
@@ -29,16 +29,72 @@
  *          Jerome Glisse
  */
 #include <linux/module.h>
-#include <ttm/ttm_module.h>
+#include <linux/device.h>
+#include <linux/sched.h>
+#include "ttm/ttm_module.h"
+#include "drm_sysfs.h"
+
+static DECLARE_WAIT_QUEUE_HEAD(exit_q);
+atomic_t device_released;
+
+static struct device_type ttm_drm_class_type = {
+        .name = "ttm",
+        /**
+         * Add pm ops here.
+         */
+};
+
+static void ttm_drm_class_device_release(struct device *dev)
+{
+        atomic_set(&device_released, 1);
+        wake_up_all(&exit_q);
+}
+
+static struct device ttm_drm_class_device = {
+        .type = &ttm_drm_class_type,
+        .release = &ttm_drm_class_device_release
+};
+
+struct kobject *ttm_get_kobj(void)
+{
+        struct kobject *kobj = &ttm_drm_class_device.kobj;
+        BUG_ON(kobj == NULL);
+        return kobj;
+}
 
 static int __init ttm_init(void)
 {
+        int ret;
+
+        ret = dev_set_name(&ttm_drm_class_device, "ttm");
+        if (unlikely(ret != 0))
+                return ret;
+
         ttm_global_init();
+
+        atomic_set(&device_released, 0);
+        ret = drm_class_device_register(&ttm_drm_class_device);
+        if (unlikely(ret != 0))
+                goto out_no_dev_reg;
+
         return 0;
+out_no_dev_reg:
+        atomic_set(&device_released, 1);
+        wake_up_all(&exit_q);
+        ttm_global_release();
+        return ret;
 }
 
 static void __exit ttm_exit(void)
 {
+        drm_class_device_unregister(&ttm_drm_class_device);
+
+        /**
+         * Refuse to unload until the TTM device is released.
+         * Not sure this is 100% needed.
+         */
+
+        wait_event(exit_q, atomic_read(&device_released) == 1);
         ttm_global_release();
 }