Commit 62496658 authored by Mikulas Patocka's avatar Mikulas Patocka Committed by Tomi Valkeinen
Browse files

tgafb: fix mode setting with fbset 



Mode setting in the TGA driver is broken for these reasons:

- info->fix.line_length is set just once in tgafb_init_fix function. If
  we change videomode, info->fix.line_length is not recalculated - so
  the video mode is changed but the screen is corrupted because of wrong
  info->fix.line_length.

- info->fix.smem_len is set in tgafb_init_fix to the size of the default
  video mode (640x480). If we set a higher resolution,
  info->fix.smem_len is smaller than the current screen size, preventing
  the userspace program from mapping the framebuffer.

This patch fixes it:

- info->fix.line_length initialization is moved to tgafb_set_par so that
  it is recalculated with each mode change.

- info->fix.smem_len is set to a fixed value representing the real
  amount of video ram (the values are taken from xfree86 driver).

- add a check to tgafb_check_var to prevent us from setting a videomode
  that doesn't fit into videoram.

- in tgafb_register, tgafb_init_fix is moved upwards, to be called
  before fb_find_mode (because fb_find_mode already needs the videoram
  size set in tgafb_init_fix).

Signed-off-by: default avatarMikulas Patocka <mpatocka@redhat.com>
Cc: stable@vga.kernel.org
Signed-off-by: default avatarTomi Valkeinen <tomi.valkeinen@ti.com>
parent 43751a1b

drivers/video/tgafb.c

+14 −4
Original line number Diff line number Diff line
@@ -182,6 +182,8 @@ tgafb_check_var(struct fb_var_screeninfo *var, struct fb_info *info) 


	if (var->xres_virtual != var->xres || var->yres_virtual != var->yres)

		return -EINVAL;

	if (var->xres * var->yres * (var->bits_per_pixel >> 3) > info->fix.smem_len)

		return -EINVAL;

	if (var->nonstd)

		return -EINVAL;

	if (1000000000 / var->pixclock > TGA_PLL_MAX_FREQ)
@@ -262,6 +264,7 @@ tgafb_set_par(struct fb_info *info) 
	par->yres = info->var.yres;

	par->pll_freq = pll_freq = 1000000000 / info->var.pixclock;

	par->bits_per_pixel = info->var.bits_per_pixel;

	info->fix.line_length = par->xres * (par->bits_per_pixel >> 3);



	tga_type = par->tga_type;
@@ -1470,6 +1473,7 @@ tgafb_init_fix(struct fb_info *info) 
	int tga_bus_tc = TGA_BUS_TC(par->dev);

	u8 tga_type = par->tga_type;

	const char *tga_type_name = NULL;

	unsigned memory_size;



	switch (tga_type) {

	case TGA_TYPE_8PLANE:
@@ -1477,22 +1481,27 @@ tgafb_init_fix(struct fb_info *info) 
			tga_type_name = "Digital ZLXp-E1";

		if (tga_bus_tc)

			tga_type_name = "Digital ZLX-E1";

		memory_size = 2097152;

		break;

	case TGA_TYPE_24PLANE:

		if (tga_bus_pci)

			tga_type_name = "Digital ZLXp-E2";

		if (tga_bus_tc)

			tga_type_name = "Digital ZLX-E2";

		memory_size = 8388608;

		break;

	case TGA_TYPE_24PLUSZ:

		if (tga_bus_pci)

			tga_type_name = "Digital ZLXp-E3";

		if (tga_bus_tc)

			tga_type_name = "Digital ZLX-E3";

		memory_size = 16777216;

		break;

	}

	if (!tga_type_name)

	if (!tga_type_name) {

		tga_type_name = "Unknown";

		memory_size = 16777216;

	}



	strlcpy(info->fix.id, tga_type_name, sizeof(info->fix.id));
@@ -1502,9 +1511,8 @@ tgafb_init_fix(struct fb_info *info) 
			    ? FB_VISUAL_PSEUDOCOLOR

			    : FB_VISUAL_DIRECTCOLOR);



	info->fix.line_length = par->xres * (par->bits_per_pixel >> 3);

	info->fix.smem_start = (size_t) par->tga_fb_base;

	info->fix.smem_len = info->fix.line_length * par->yres;

	info->fix.smem_len = memory_size;

	info->fix.mmio_start = (size_t) par->tga_regs_base;

	info->fix.mmio_len = 512;
@@ -1628,6 +1636,9 @@ static int tgafb_register(struct device *dev) 
		modedb_tga = &modedb_tc;

		modedbsize_tga = 1;

	}



	tgafb_init_fix(info);



	ret = fb_find_mode(&info->var, info,

			   mode_option ? mode_option : mode_option_tga,

			   modedb_tga, modedbsize_tga, NULL,
@@ -1645,7 +1656,6 @@ static int tgafb_register(struct device *dev) 
	}



	tgafb_set_par(info);

	tgafb_init_fix(info);



	if (register_framebuffer(info) < 0) {

		printk(KERN_ERR "tgafb: Could not register framebuffer\n");

CRA Git | Maintained and supported by SUSTech CRA and CCSE