[PATCH] fbdev: q40fb: request memory region

[Sukrut Heroorkar <hsukrut3@gmail.com>]

The q40fb driver uses a fixed physical address but never reserves
the corresponding I/O region. Reserve the range  as suggested in
Documentation/gpu/todo.rst ("Request memory regions in all fbdev drivers").

No functional change beyond claming the resource. This change is compile
tested only.

Signed-off-by: Sukrut Heroorkar <hsukrut3@gmail.com>
---
 drivers/video/fbdev/q40fb.c | 7 +++++++
 1 file changed, 7 insertions(+)

diff --git a/drivers/video/fbdev/q40fb.c b/drivers/video/fbdev/q40fb.c
index 1ff8fa176124..935260326c6f 100644
--- a/drivers/video/fbdev/q40fb.c
+++ b/drivers/video/fbdev/q40fb.c
@@ -101,6 +101,12 @@ static int q40fb_probe(struct platform_device *dev)
 	info->par = NULL;
 	info->screen_base = (char *) q40fb_fix.smem_start;
 
+	if (!request_mem_region(q40fb_fix.smem_start, q40fb_fix.smem_len,
+				"q40fb")) {
+		dev_err(&dev->dev, "cannot reserve video memory at 0x%lx\n",
+			q40fb_fix.smem_start);
+	}
+
 	if (fb_alloc_cmap(&info->cmap, 256, 0) < 0) {
 		framebuffer_release(info);
 		return -ENOMEM;
@@ -144,6 +150,7 @@ static int __init q40fb_init(void)
 		if (ret)
 			platform_driver_unregister(&q40fb_driver);
 	}
+
 	return ret;
 }
 
-- 
2.43.0