[PATCH v4 3/6] drm/etnaviv: add dedicated functions to create and destroy platform devices

[Sui Jingfeng]

Also rename the virtual master platform device as etnaviv_platform_device,
for better reflection that it is a platform device, not a DRM device.

Another benefit is that we no longer need to call of_node_put() for three
different cases, Instead, we only need to call it once.

Signed-off-by: Sui Jingfeng <suijingf...@loongson.cn>
---
 drivers/gpu/drm/etnaviv/etnaviv_drv.c | 56 +++++++++++++++++++--------
 1 file changed, 39 insertions(+), 17 deletions(-)

diff --git a/drivers/gpu/drm/etnaviv/etnaviv_drv.c 
b/drivers/gpu/drm/etnaviv/etnaviv_drv.c
index 31a7f59ccb49..0a9d90c18f2c 100644
--- a/drivers/gpu/drm/etnaviv/etnaviv_drv.c
+++ b/drivers/gpu/drm/etnaviv/etnaviv_drv.c
@@ -656,12 +656,44 @@ static struct platform_driver etnaviv_platform_driver = {
        },
 };
 
-static struct platform_device *etnaviv_drm;
+static struct platform_device *etnaviv_platform_device;
 
-static int __init etnaviv_init(void)
+static int etnaviv_create_platform_device(const char *name,
+                                         struct platform_device **ppdev)
 {
        struct platform_device *pdev;
        int ret;
+
+       pdev = platform_device_alloc(name, PLATFORM_DEVID_NONE);
+       if (!pdev)
+               return -ENOMEM;
+
+       ret = platform_device_add(pdev);
+       if (ret) {
+               platform_device_put(pdev);
+               return ret;
+       }
+
+       *ppdev = pdev;
+
+       return 0;
+}
+
+static void etnaviv_destroy_platform_device(struct platform_device **ppdev)
+{
+       struct platform_device *pdev = *ppdev;
+
+       if (!pdev)
+               return;
+
+       *ppdev = NULL;
+
+       platform_device_unregister(pdev);
+}
+
+static int __init etnaviv_init(void)
+{
+       int ret;
        struct device_node *np;
 
        etnaviv_validate_init();
@@ -682,22 +714,12 @@ static int __init etnaviv_init(void)
                if (!of_device_is_available(np))
                        continue;
 
-               pdev = platform_device_alloc("etnaviv", PLATFORM_DEVID_NONE);
-               if (!pdev) {
-                       ret = -ENOMEM;
-                       of_node_put(np);
-                       goto unregister_platform_driver;
-               }
-
-               ret = platform_device_add(pdev);
-               if (ret) {
-                       platform_device_put(pdev);
-                       of_node_put(np);
+               ret = etnaviv_create_platform_device("etnaviv",
+                                                    &etnaviv_platform_device);
+               of_node_put(np);
+               if (ret)
                        goto unregister_platform_driver;
-               }
 
-               etnaviv_drm = pdev;
-               of_node_put(np);
                break;
        }
 
@@ -713,7 +735,7 @@ module_init(etnaviv_init);
 
 static void __exit etnaviv_exit(void)
 {
-       platform_device_unregister(etnaviv_drm);
+       etnaviv_destroy_platform_device(&etnaviv_platform_device);
        platform_driver_unregister(&etnaviv_platform_driver);
        platform_driver_unregister(&etnaviv_gpu_driver);
 }
-- 
2.25.1