[PATCH] staging: fbtft: add typecast in call to vfree()

[PATCH] staging: fbtft: add typecast in call to vfree()

[Lars Svensson]

Member screen_base in struct fb_info is declared __iomem causing
a sparse warning as below when passed to vfree(). This adds typecast
(__force void *) to silence the warning.

fbtft-core.c:922:39: warning: incorrect type in argument 1 \
(different address spaces)
fbtft-core.c:922:39:    expected void const *addr
fbtft-core.c:922:39:    got char [noderef] <asn:2>*screen_base

Signed-off-by: Lars Svensson <lars1.svensson@sonymobile.com>
---
 drivers/staging/fbtft/fbtft-core.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/drivers/staging/fbtft/fbtft-core.c b/drivers/staging/fbtft/fbtft-core.c
index 7f5fa3d..3e91fb5 100644
--- a/drivers/staging/fbtft/fbtft-core.c
+++ b/drivers/staging/fbtft/fbtft-core.c
@@ -919,7 +919,7 @@ EXPORT_SYMBOL(fbtft_framebuffer_alloc);
 void fbtft_framebuffer_release(struct fb_info *info)
 {
 	fb_deferred_io_cleanup(info);
-	vfree(info->screen_base);
+	vfree((__force void *)info->screen_base);
 	framebuffer_release(info);
 }
 EXPORT_SYMBOL(fbtft_framebuffer_release);
-- 
2.4.2

Re: [PATCH] staging: fbtft: add typecast in call to vfree()

[Dan Carpenter]

On Thu, Oct 01, 2015 at 03:00:12PM +0200, Lars Svensson wrote:
> Member screen_base in struct fb_info is declared __iomem causing
> a sparse warning as below when passed to vfree(). This adds typecast
> (__force void *) to silence the warning.
> 
> fbtft-core.c:922:39: warning: incorrect type in argument 1 \
> (different address spaces)
> fbtft-core.c:922:39:    expected void const *addr
> fbtft-core.c:922:39:    got char [noderef] <asn:2>*screen_base
> 

I thought we were going to do something like this:

diff --git a/include/linux/fb.h b/include/linux/fb.h
index be40dba..3324c92 100644
--- a/include/linux/fb.h
+++ b/include/linux/fb.h
@@ -483,7 +483,10 @@ struct fb_info {
 #ifdef CONFIG_FB_TILEBLITTING
 	struct fb_tile_ops *tileops;    /* Tile Blitting */
 #endif
-	char __iomem *screen_base;	/* Virtual address */
+	union {
+		char __iomem *screen_base;	/* Virtual address */
+		char *fake_screen_base;
+	};
 	unsigned long screen_size;	/* Amount of ioremapped VRAM or 0 */ 
 	void *pseudo_palette;		/* Fake palette of 16 colors */ 
 #define FBINFO_STATE_RUNNING	0

The only question is what to call the fake_screen_base.

regards,
dan carpenter