From: "Antonino A. Daplas" <adaplas@hotpop.com>
Sigh, this patch uncovered a can of worms. I tested different combinations,
those with/without xxxfb_blank implementation, framebuffers in directcolor
or truecolor, etc. I find that there is a problem unblanking if the hardware
has no xxxfb_blank() implementation, and also that the generic fb_blank() in
fbmem.c is problematic with drivers in directcolor or pseudocolor mode when
called by an fb application such as X.
Display blanking is implemented in three ways:
1. using the drivers blanking implementation - info->fbops->fb_blank()
2. clearing the screen with the console erase character - fbcon_blank()
3. setting the color map to all black - fb_blank()
The third method is problematic for these reasons:
- Setting the colormap to all black will not work in truecolor mode
- In directcolor or pseudocolor, it will overwrite the fb application's
color map, producing wrong colors.
So, remove the generic implementation in fb_blank() and just return -EINVAL
if there is no hardware implementation. This will be only used by apps doing
an FBIO_BLANK ioctl, and is a more robust approach.
Other changes:
- Consolidated all tests and created an inlined helper function to check if
the framebuffer console is inactive or not.
- fix unblanking if driver has no xxxfb_blank() hook.
I'm probably missing a few more things, but this patch should be generally
correct. Please apply after the entire patch series to avoid rejects.
Signed-off-by: Antonino Daplas <adaplas@pol.net>
Signed-off-by: Andrew Morton <akpm@osdl.org>
---
25-akpm/drivers/video/console/fbcon.c | 61 +++++++++++++---------------------
25-akpm/drivers/video/fbmem.c | 25 +------------
2 files changed, 28 insertions(+), 58 deletions(-)
diff -puN drivers/video/console/fbcon.c~fbcon-do-not-touch-hardware-if-vc_mode-=-kd_text-fix drivers/video/console/fbcon.c
--- 25/drivers/video/console/fbcon.c~fbcon-do-not-touch-hardware-if-vc_mode-=-kd_text-fix Wed Nov 3 15:49:32 2004
+++ 25-akpm/drivers/video/console/fbcon.c Wed Nov 3 15:49:32 2004
@@ -200,6 +200,13 @@ static irqreturn_t fb_vbl_detect(int irq
}
#endif
+static inline int fbcon_is_inactive(struct vc_data *vc, struct fb_info *info)
+{
+ return (info->state != FBINFO_STATE_RUNNING ||
+ vt_cons[vc->vc_num]->vc_mode != KD_TEXT ||
+ (console_blanked && info->fbops->fb_blank));
+}
+
static inline int get_color(struct vc_data *vc, struct fb_info *info,
u16 c, int is_fg)
{
@@ -252,9 +259,8 @@ static void fb_flashcursor(void *private
if (ops->currcon != -1)
vc = vc_cons[ops->currcon].d;
- if (info->state != FBINFO_STATE_RUNNING ||
- !vc || !CON_IS_VISIBLE(vc) ||
- vt_cons[vc->vc_num]->vc_mode != KD_TEXT ||
+ if (!vc || !CON_IS_VISIBLE(vc) ||
+ fbcon_is_inactive(vc, info) ||
registered_fb[con2fb_map[vc->vc_num]] != info)
return;
acquire_console_sem();
@@ -988,12 +994,7 @@ static void fbcon_clear(struct vc_data *
struct display *p = &fb_display[vc->vc_num];
u_int y_break;
- if (!info->fbops->fb_blank && console_blanked)
- return;
- if (info->state != FBINFO_STATE_RUNNING)
- return;
-
- if (vt_cons[vc->vc_num]->vc_mode != KD_TEXT)
+ if (fbcon_is_inactive(vc, info))
return;
if (!height || !width)
@@ -1018,18 +1019,10 @@ static void fbcon_putcs(struct vc_data *
struct display *p = &fb_display[vc->vc_num];
struct fbcon_ops *ops = info->fbcon_par;
- if (!info->fbops->fb_blank && console_blanked)
- return;
-
- if (info->state != FBINFO_STATE_RUNNING)
- return;
-
- if (vt_cons[vc->vc_num]->vc_mode != KD_TEXT)
- return;
-
- ops->putcs(vc, info, s, count, real_y(p, ypos), xpos,
- get_color(vc, info, scr_readw(s), 1),
- get_color(vc, info, scr_readw(s), 0));
+ if (!fbcon_is_inactive(vc, info))
+ ops->putcs(vc, info, s, count, real_y(p, ypos), xpos,
+ get_color(vc, info, scr_readw(s), 1),
+ get_color(vc, info, scr_readw(s), 0));
}
static void fbcon_putc(struct vc_data *vc, int c, int ypos, int xpos)
@@ -1045,7 +1038,8 @@ static void fbcon_clear_margins(struct v
struct fb_info *info = registered_fb[con2fb_map[vc->vc_num]];
struct fbcon_ops *ops = info->fbcon_par;
- ops->clear_margins(vc, info, bottom_only);
+ if (!fbcon_is_inactive(vc, info))
+ ops->clear_margins(vc, info, bottom_only);
}
static void fbcon_cursor(struct vc_data *vc, int mode)
@@ -1056,7 +1050,7 @@ static void fbcon_cursor(struct vc_data
int y = real_y(p, vc->vc_y);
int c = scr_readw((u16 *) vc->vc_pos);
- if (vt_cons[vc->vc_num]->vc_mode != KD_TEXT)
+ if (fbcon_is_inactive(vc, info))
return;
ops->cursor_flash = 1;
@@ -1511,11 +1505,8 @@ static int fbcon_scroll(struct vc_data *
struct fbcon_ops *ops = info->fbcon_par;
int scroll_partial = info->flags & FBINFO_PARTIAL_PAN_OK;
- if (!info->fbops->fb_blank && console_blanked)
- return 0;
-
- if (!count || vt_cons[vc->vc_num]->vc_mode != KD_TEXT)
- return 0;
+ if (fbcon_is_inactive(vc, info))
+ return -EINVAL;
fbcon_cursor(vc, CM_ERASE);
@@ -1704,10 +1695,7 @@ static void fbcon_bmove(struct vc_data *
struct fb_info *info = registered_fb[con2fb_map[vc->vc_num]];
struct display *p = &fb_display[vc->vc_num];
- if (!info->fbops->fb_blank && console_blanked)
- return;
-
- if (vt_cons[vc->vc_num]->vc_mode != KD_TEXT)
+ if (fbcon_is_inactive(vc, info))
return;
if (!width || !height)
@@ -1999,8 +1987,8 @@ static int fbcon_blank(struct vc_data *v
return 0;
}
- ops->cursor_flash = (!blank);
fbcon_cursor(vc, blank ? CM_ERASE : CM_DRAW);
+ ops->cursor_flash = (!blank);
if (!info->fbops->fb_blank) {
if (blank) {
@@ -2019,10 +2007,10 @@ static int fbcon_blank(struct vc_data *v
} else
fbcon_clear(vc, 0, 0, height, vc->vc_cols);
vc->vc_video_erase_char = oldc;
- } else
+ } else if (!fbcon_is_inactive(vc, info))
update_screen(vc->vc_num);
} else if (vt_cons[vc->vc_num]->vc_mode == KD_TEXT)
- retval = fb_blank(info, blank);
+ retval = info->fbops->fb_blank(blank, info);
return retval;
}
@@ -2328,8 +2316,9 @@ static int fbcon_set_palette(struct vc_d
int i, j, k, depth;
u8 val;
- if (!info->fbops->fb_blank && console_blanked)
+ if (fbcon_is_inactive(vc, info))
return -EINVAL;
+
depth = fb_get_color_depth(info);
if (depth > 3) {
for (i = j = 0; i < 16; i++) {
diff -puN drivers/video/fbmem.c~fbcon-do-not-touch-hardware-if-vc_mode-=-kd_text-fix drivers/video/fbmem.c
--- 25/drivers/video/fbmem.c~fbcon-do-not-touch-hardware-if-vc_mode-=-kd_text-fix Wed Nov 3 15:49:32 2004
+++ 25-akpm/drivers/video/fbmem.c Wed Nov 3 15:49:32 2004
@@ -743,33 +743,14 @@ fb_set_var(struct fb_info *info, struct
int
fb_blank(struct fb_info *info, int blank)
{
- /* ??? Variable sized stack allocation. */
- struct fb_cmap cmap;
- u16 *black = NULL;
- int err = 0;
+ int err = -EINVAL;
/* Workaround for broken X servers */
if (blank > VESA_POWERDOWN)
blank = VESA_POWERDOWN;
- if (info->fbops->fb_blank && !info->fbops->fb_blank(blank, info))
- return 0;
-
- cmap = info->cmap;
-
- if (blank) {
- black = kmalloc(sizeof(u16) * info->cmap.len, GFP_KERNEL);
- if (black) {
- memset(black, 0, info->cmap.len * sizeof(u16));
- cmap.red = cmap.green = cmap.blue = black;
- cmap.transp = info->cmap.transp ? black : NULL;
- cmap.start = info->cmap.start;
- cmap.len = info->cmap.len;
- }
- }
-
- err = fb_set_cmap(&cmap, info);
- kfree(black);
+ if (info->fbops->fb_blank)
+ err = info->fbops->fb_blank(blank, info);
return err;
}
_