atmel_lcdfb: validate display timings

[linux-2.6-omap-h63xx.git] / drivers / video / atmel_lcdfb.c

diff --git a/drivers/video/atmel_lcdfb.c b/drivers/video/atmel_lcdfb.c
index f8e711147501079011887cc86f65365b04b1cf46..5d22ea532e421516fb9ceb3bddbdeddb09c7b4ba 100644 (file)
--- a/drivers/video/atmel_lcdfb.c
+++ b/drivers/video/atmel_lcdfb.c
@@ -203,6 +203,26 @@ static int atmel_lcdfb_check_var(struct fb_var_screeninfo *var,
        var->transp.offset = var->transp.length = 0;
        var->xoffset = var->yoffset = 0;
 
+       /* Saturate vertical and horizontal timings at maximum values */
+       var->vsync_len = min_t(u32, var->vsync_len,
+                       (ATMEL_LCDC_VPW >> ATMEL_LCDC_VPW_OFFSET) + 1);
+       var->upper_margin = min_t(u32, var->upper_margin,
+                       ATMEL_LCDC_VBP >> ATMEL_LCDC_VBP_OFFSET);
+       var->lower_margin = min_t(u32, var->lower_margin,
+                       ATMEL_LCDC_VFP);
+       var->right_margin = min_t(u32, var->right_margin,
+                       (ATMEL_LCDC_HFP >> ATMEL_LCDC_HFP_OFFSET) + 1);
+       var->hsync_len = min_t(u32, var->hsync_len,
+                       (ATMEL_LCDC_HPW >> ATMEL_LCDC_HPW_OFFSET) + 1);
+       var->left_margin = min_t(u32, var->left_margin,
+                       ATMEL_LCDC_HBP + 1);
+
+       /* Some parameters can't be zero */
+       var->vsync_len = max_t(u32, var->vsync_len, 1);
+       var->right_margin = max_t(u32, var->right_margin, 1);
+       var->hsync_len = max_t(u32, var->hsync_len, 1);
+       var->left_margin = max_t(u32, var->left_margin, 1);
+
        switch (var->bits_per_pixel) {
        case 1:
        case 2: