From 87a68cdbac416d2f79c32a474c8b8248048c9c42 Mon Sep 17 00:00:00 2001
From: notaz <notasas@gmail.com>
Date: Sat, 11 Dec 2010 17:46:39 +0000
Subject: [PATCH] fbdev: change API to make easier to avoid glitches
git-svn-id: file:///home/notaz/opt/svn/PicoDrive/platform@912 be3aeb3a-fb24-0410-a615-afba39da0efa
---
linux/fbdev.c | 26 +++++++++++++++++++-------
linux/fbdev.h | 2 +-
2 files changed, 20 insertions(+), 8 deletions(-)
diff --git a/linux/fbdev.c b/linux/fbdev.c
index b4889ea..bcef0fc 100644
--- a/linux/fbdev.c
+++ b/linux/fbdev.c
@@ -61,7 +61,8 @@ void vout_fbdev_wait_vsync(struct vout_fbdev *fbdev)
ioctl(fbdev->fd, FBIO_WAITFORVSYNC, &arg);
}
-int vout_fbdev_resize(struct vout_fbdev *fbdev, int w, int h, int bpp,
+/* it is recommended to call vout_fbdev_clear() before this */
+void *vout_fbdev_resize(struct vout_fbdev *fbdev, int w, int h, int bpp,
int left_border, int right_border, int top_border, int bottom_border, int buffer_cnt)
{
int w_total = left_border + w + right_border;
@@ -83,13 +84,20 @@ int vout_fbdev_resize(struct vout_fbdev *fbdev, int w, int h, int bpp,
fbdev->fbvar_new.xres_virtual = w_total;
fbdev->fbvar_new.yres_virtual = h_total;
fbdev->fbvar_new.xoffset = left_border;
+ fbdev->fbvar_new.yoffset = top_border;
fbdev->fbvar_new.bits_per_pixel = bpp;
printf(" switching to %dx%d@%d\n", w, h, bpp);
+
+ // seems to help a bit to avoid glitches
+ vout_fbdev_wait_vsync(fbdev);
+
ret = ioctl(fbdev->fd, FBIOPUT_VSCREENINFO, &fbdev->fbvar_new);
if (ret == -1) {
perror("FBIOPUT_VSCREENINFO ioctl");
- return -1;
+ return NULL;
}
+
+ fbdev->buffer_write = 1;
}
fbdev->buffer_count = buffer_cnt;
@@ -99,6 +107,7 @@ int vout_fbdev_resize(struct vout_fbdev *fbdev, int w, int h, int bpp,
ret = ioctl(fbdev->fd, FBIOPUT_VSCREENINFO, &fbdev->fbvar_new);
if (ret == -1) {
fbdev->buffer_count = 1;
+ fbdev->buffer_write = 0;
fprintf(stderr, "Warning: failed to increase virtual resolution, "
"doublebuffering disabled\n");
}
@@ -110,7 +119,7 @@ int vout_fbdev_resize(struct vout_fbdev *fbdev, int w, int h, int bpp,
mem_size = fbdev->fb_size * fbdev->buffer_count;
if (fbdev->mem_size >= mem_size)
- return 0;
+ goto out;
if (fbdev->mem != NULL)
munmap(fbdev->mem, fbdev->mem_size);
@@ -126,11 +135,13 @@ int vout_fbdev_resize(struct vout_fbdev *fbdev, int w, int h, int bpp,
fbdev->mem = NULL;
fbdev->mem_size = 0;
perror("mmap framebuffer");
- return -1;
+ return NULL;
}
fbdev->mem_size = mem_size;
- return 0;
+
+out:
+ return (char *)fbdev->mem + fbdev->fb_size * fbdev->buffer_write;
}
void vout_fbdev_clear(struct vout_fbdev *fbdev)
@@ -160,6 +171,7 @@ struct vout_fbdev *vout_fbdev_init(const char *fbdev_name, int *w, int *h, int b
{
struct vout_fbdev *fbdev;
int req_w, req_h;
+ void *pret;
int ret;
fbdev = calloc(1, sizeof(*fbdev));
@@ -188,8 +200,8 @@ struct vout_fbdev *vout_fbdev_init(const char *fbdev_name, int *w, int *h, int b
if (*h != 0)
req_h = *h;
- ret = vout_fbdev_resize(fbdev, req_w, req_h, bpp, 0, 0, 0, 0, buffer_cnt);
- if (ret != 0)
+ pret = vout_fbdev_resize(fbdev, req_w, req_h, bpp, 0, 0, 0, 0, buffer_cnt);
+ if (pret == NULL)
goto fail;
printf("%s: %ix%i@%d\n", fbdev_name, fbdev->fbvar_new.xres, fbdev->fbvar_new.yres,
diff --git a/linux/fbdev.h b/linux/fbdev.h
index ddbfdab..2db9163 100644
--- a/linux/fbdev.h
+++ b/linux/fbdev.h
@@ -3,7 +3,7 @@ struct vout_fbdev;
struct vout_fbdev *vout_fbdev_init(const char *fbdev_name, int *w, int *h, int bpp, int buffer_count);
void *vout_fbdev_flip(struct vout_fbdev *fbdev);
void vout_fbdev_wait_vsync(struct vout_fbdev *fbdev);
-int vout_fbdev_resize(struct vout_fbdev *fbdev, int w, int h, int bpp,
+void *vout_fbdev_resize(struct vout_fbdev *fbdev, int w, int h, int bpp,
int left_border, int right_border, int top_border, int bottom_border,
int buffer_count);
void vout_fbdev_clear(struct vout_fbdev *fbdev);
--
2.39.5