fbdev: defio and Metronomefb
Implement support for the E-Ink Metronome controller. It provides an mmapable
interface to the controller using defio support. It was tested with a gumstix
pxa255 with Vizplex media using Xfbdev and various X clients such as xeyes,
xpdf, xloadimage.
This patch also fixes the following bug: Defio would cause a hang on write
access to the framebuffer as the page fault would be called ad-infinitum. It
fixes fb_defio by setting the mapping to be used by page_mkclean.
Signed-off-by: Jaya Kumar <jayakumar.lkml@gmail.com>
Cc: "Antonino A. Daplas" <adaplas@pol.net>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
diff --git a/drivers/video/fb_defio.c b/drivers/video/fb_defio.c
index 0f8cfb9..24843fd 100644
--- a/drivers/video/fb_defio.c
+++ b/drivers/video/fb_defio.c
@@ -4,7 +4,7 @@
* Copyright (C) 2006 Jaya Kumar
*
* This file is subject to the terms and conditions of the GNU General Public
- * License. See the file COPYING in the main directory of this archive
+ * License. See the file COPYING in the main directory of this archive
* for more details.
*/
@@ -31,7 +31,7 @@
unsigned long offset;
struct page *page;
struct fb_info *info = vma->vm_private_data;
- /* info->screen_base is in System RAM */
+ /* info->screen_base is virtual memory */
void *screen_base = (void __force *) info->screen_base;
offset = vmf->pgoff << PAGE_SHIFT;
@@ -43,6 +43,15 @@
return VM_FAULT_SIGBUS;
get_page(page);
+
+ if (vma->vm_file)
+ page->mapping = vma->vm_file->f_mapping;
+ else
+ printk(KERN_ERR "no mapping available\n");
+
+ BUG_ON(!page->mapping);
+ page->index = vmf->pgoff;
+
vmf->page = page;
return 0;
}
@@ -138,11 +147,20 @@
void fb_deferred_io_cleanup(struct fb_info *info)
{
+ void *screen_base = (void __force *) info->screen_base;
struct fb_deferred_io *fbdefio = info->fbdefio;
+ struct page *page;
+ int i;
BUG_ON(!fbdefio);
cancel_delayed_work(&info->deferred_work);
flush_scheduled_work();
+
+ /* clear out the mapping that we setup */
+ for (i = 0 ; i < info->fix.smem_len; i += PAGE_SIZE) {
+ page = vmalloc_to_page(screen_base + i);
+ page->mapping = NULL;
+ }
}
EXPORT_SYMBOL_GPL(fb_deferred_io_cleanup);