OMAP: DSS2: OMAPFB: Reduce stack usage

omapfb_mode_to_timings() had struct fb_info, struct fb_var and struct
fb_ops allocated from stack. This caused the stack usage grow quite
high.

Use kzalloc to allocate the structs instead.

Signed-off-by: Tomi Valkeinen <tomi.valkeinen@ti.com>

diff --git a/drivers/video/omap2/omapfb/omapfb-main.c b/drivers/video/omap2/omapfb/omapfb-main.c
index 9a5b4bc81c80adca45c1496b59d176fd384780be..505bc12a3031a877ad5617a0259dce21f519f970 100644 (file)
--- a/drivers/video/omap2/omapfb/omapfb-main.c
+++ b/drivers/video/omap2/omapfb/omapfb-main.c
@@ -1996,9 +1996,9 @@ static int omapfb_create_framebuffers(struct omapfb2_device *fbdev)
 static int omapfb_mode_to_timings(const char *mode_str,
                struct omap_video_timings *timings, u8 *bpp)
 {
-       struct fb_info fbi;
-       struct fb_var_screeninfo var;
-       struct fb_ops fbops;
+       struct fb_info *fbi;
+       struct fb_var_screeninfo *var;
+       struct fb_ops *fbops;
        int r;
 
 #ifdef CONFIG_OMAP2_DSS_VENC
@@ -2016,39 +2016,66 @@ static int omapfb_mode_to_timings(const char *mode_str,
        /* this is quite a hack, but I wanted to use the modedb and for
         * that we need fb_info and var, so we create dummy ones */
 
-       memset(&fbi, 0, sizeof(fbi));
-       memset(&var, 0, sizeof(var));
-       memset(&fbops, 0, sizeof(fbops));
-       fbi.fbops = &fbops;
-
-       r = fb_find_mode(&var, &fbi, mode_str, NULL, 0, NULL, 24);
-
-       if (r != 0) {
-               timings->pixel_clock = PICOS2KHZ(var.pixclock);
-               timings->hbp = var.left_margin;
-               timings->hfp = var.right_margin;
-               timings->vbp = var.upper_margin;
-               timings->vfp = var.lower_margin;
-               timings->hsw = var.hsync_len;
-               timings->vsw = var.vsync_len;
-               timings->x_res = var.xres;
-               timings->y_res = var.yres;
-
-               switch (var.bits_per_pixel) {
-               case 16:
-                       *bpp = 16;
-                       break;
-               case 24:
-               case 32:
-               default:
-                       *bpp = 24;
-                       break;
-               }
+       *bpp = 0;
+       fbi = NULL;
+       var = NULL;
+       fbops = NULL;
 
-               return 0;
-       } else {
-               return -EINVAL;
+       fbi = kzalloc(sizeof(*fbi), GFP_KERNEL);
+       if (fbi == NULL) {
+               r = -ENOMEM;
+               goto err;
+       }
+
+       var = kzalloc(sizeof(*var), GFP_KERNEL);
+       if (var == NULL) {
+               r = -ENOMEM;
+               goto err;
+       }
+
+       fbops = kzalloc(sizeof(*fbops), GFP_KERNEL);
+       if (fbops == NULL) {
+               r = -ENOMEM;
+               goto err;
+       }
+
+       fbi->fbops = fbops;
+
+       r = fb_find_mode(var, fbi, mode_str, NULL, 0, NULL, 24);
+       if (r == 0) {
+               r = -EINVAL;
+               goto err;
        }
+
+       timings->pixel_clock = PICOS2KHZ(var->pixclock);
+       timings->hbp = var->left_margin;
+       timings->hfp = var->right_margin;
+       timings->vbp = var->upper_margin;
+       timings->vfp = var->lower_margin;
+       timings->hsw = var->hsync_len;
+       timings->vsw = var->vsync_len;
+       timings->x_res = var->xres;
+       timings->y_res = var->yres;
+
+       switch (var->bits_per_pixel) {
+       case 16:
+               *bpp = 16;
+               break;
+       case 24:
+       case 32:
+       default:
+               *bpp = 24;
+               break;
+       }
+
+       r = 0;
+
+err:
+       kfree(fbi);
+       kfree(var);
+       kfree(fbops);
+
+       return r;
 }
 
 static int omapfb_set_def_mode(struct omapfb2_device *fbdev,