[PATCH RESEND drm-misc 1/4] drm/dp: make drm_dp_aux_dev_class constant

[Ricardo B. Marliere]

Since commit 43a7206b0963 ("driver core: class: make class_register() take
a const *"), the driver core allows for struct class to be in read-only
memory, so move the drm_dp_aux_dev_class structure to be declared at build
time placing it into read-only memory, instead of having to be dynamically
allocated at boot time.

Cc: Greg Kroah-Hartman <gre...@linuxfoundation.org>
Suggested-by: Greg Kroah-Hartman <gre...@linuxfoundation.org>
Signed-off-by: Ricardo B. Marliere <rica...@marliere.net>
---
 drivers/gpu/drm/display/drm_dp_aux_dev.c | 22 ++++++++++++----------
 1 file changed, 12 insertions(+), 10 deletions(-)

diff --git a/drivers/gpu/drm/display/drm_dp_aux_dev.c 
b/drivers/gpu/drm/display/drm_dp_aux_dev.c
index 29555b9f03c8..213abde5b09f 100644
--- a/drivers/gpu/drm/display/drm_dp_aux_dev.c
+++ b/drivers/gpu/drm/display/drm_dp_aux_dev.c
@@ -54,7 +54,6 @@ struct drm_dp_aux_dev {
 #define AUX_MAX_OFFSET (1 << 20)
 static DEFINE_IDR(aux_idr);
 static DEFINE_MUTEX(aux_idr_mutex);
-static struct class *drm_dp_aux_dev_class;
 static int drm_dev_major = -1;
 
 static struct drm_dp_aux_dev *drm_dp_aux_dev_get_by_minor(unsigned index)
@@ -125,6 +124,11 @@ static struct attribute *drm_dp_aux_attrs[] = {
 };
 ATTRIBUTE_GROUPS(drm_dp_aux);
 
+static const struct class drm_dp_aux_dev_class = {
+       .name = "drm_dp_aux_dev",
+       .dev_groups = drm_dp_aux_groups,
+};
+
 static int auxdev_open(struct inode *inode, struct file *file)
 {
        unsigned int minor = iminor(inode);
@@ -293,7 +297,7 @@ void drm_dp_aux_unregister_devnode(struct drm_dp_aux *aux)
 
        minor = aux_dev->index;
        if (aux_dev->dev)
-               device_destroy(drm_dp_aux_dev_class,
+               device_destroy(&drm_dp_aux_dev_class,
                               MKDEV(drm_dev_major, minor));
 
        DRM_DEBUG("drm_dp_aux_dev: aux [%s] unregistering\n", aux->name);
@@ -309,7 +313,7 @@ int drm_dp_aux_register_devnode(struct drm_dp_aux *aux)
        if (IS_ERR(aux_dev))
                return PTR_ERR(aux_dev);
 
-       aux_dev->dev = device_create(drm_dp_aux_dev_class, aux->dev,
+       aux_dev->dev = device_create(&drm_dp_aux_dev_class, aux->dev,
                                     MKDEV(drm_dev_major, aux_dev->index), NULL,
                                     "drm_dp_aux%d", aux_dev->index);
        if (IS_ERR(aux_dev->dev)) {
@@ -330,11 +334,9 @@ int drm_dp_aux_dev_init(void)
 {
        int res;
 
-       drm_dp_aux_dev_class = class_create("drm_dp_aux_dev");
-       if (IS_ERR(drm_dp_aux_dev_class)) {
-               return PTR_ERR(drm_dp_aux_dev_class);
-       }
-       drm_dp_aux_dev_class->dev_groups = drm_dp_aux_groups;
+       res = class_register(&drm_dp_aux_dev_class);
+       if (res)
+               return res;
 
        res = register_chrdev(0, "aux", &auxdev_fops);
        if (res < 0)
@@ -343,12 +345,12 @@ int drm_dp_aux_dev_init(void)
 
        return 0;
 out:
-       class_destroy(drm_dp_aux_dev_class);
+       class_unregister(&drm_dp_aux_dev_class);
        return res;
 }
 
 void drm_dp_aux_dev_exit(void)
 {
        unregister_chrdev(drm_dev_major, "aux");
-       class_destroy(drm_dp_aux_dev_class);
+       class_unregister(&drm_dp_aux_dev_class);
 }

-- 
2.43.0