[PATCH] atmel_lcdfb: Validate display timings
From: Haavard Skinnemoen <hidden>
Date: 2007-11-29 13:52:01
Also in:
lkml
Subsystem:
framebuffer layer, microchip lcdfb driver, the rest · Maintainers:
Helge Deller, Nicolas Ferre, Linus Torvalds
Setting a display timing parameter too high or too low may cause it to wrap around and thus become completely wrong. Validate the timings in atmel_lcdfb_check_var() and saturate to the highest or lowest possible value if necessary. Signed-off-by: Haavard Skinnemoen <redacted> --- drivers/video/atmel_lcdfb.c | 20 ++++++++++++++++++++ include/video/atmel_lcdc.h | 14 +++++++------- 2 files changed, 27 insertions(+), 7 deletions(-)
diff --git a/drivers/video/atmel_lcdfb.c b/drivers/video/atmel_lcdfb.c
index 235b618..58d49e4 100644
--- 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:
diff --git a/include/video/atmel_lcdc.h b/include/video/atmel_lcdc.h
index 4eea637..76095e7 100644
--- a/include/video/atmel_lcdc.h
+++ b/include/video/atmel_lcdc.h@@ -115,20 +115,20 @@ struct atmel_lcdfb_info { #define ATMEL_LCDC_MEMOR_LITTLE (1 << 31) #define ATMEL_LCDC_TIM1 0x0808 -#define ATMEL_LCDC_VFP (0xff << 0) +#define ATMEL_LCDC_VFP (0xffU << 0) #define ATMEL_LCDC_VBP_OFFSET 8 -#define ATMEL_LCDC_VBP (0xff << ATMEL_LCDC_VBP_OFFSET) +#define ATMEL_LCDC_VBP (0xffU << ATMEL_LCDC_VBP_OFFSET) #define ATMEL_LCDC_VPW_OFFSET 16 -#define ATMEL_LCDC_VPW (0x3f << ATMEL_LCDC_VPW_OFFSET) +#define ATMEL_LCDC_VPW (0x3fU << ATMEL_LCDC_VPW_OFFSET) #define ATMEL_LCDC_VHDLY_OFFSET 24 -#define ATMEL_LCDC_VHDLY (0xf << ATMEL_LCDC_VHDLY_OFFSET) +#define ATMEL_LCDC_VHDLY (0xfU << ATMEL_LCDC_VHDLY_OFFSET) #define ATMEL_LCDC_TIM2 0x080c -#define ATMEL_LCDC_HBP (0xff << 0) +#define ATMEL_LCDC_HBP (0xffU << 0) #define ATMEL_LCDC_HPW_OFFSET 8 -#define ATMEL_LCDC_HPW (0x3f << ATMEL_LCDC_HPW_OFFSET) +#define ATMEL_LCDC_HPW (0x3fU << ATMEL_LCDC_HPW_OFFSET) #define ATMEL_LCDC_HFP_OFFSET 21 -#define ATMEL_LCDC_HFP (0x7ff << ATMEL_LCDC_HFP_OFFSET) +#define ATMEL_LCDC_HFP (0x7ffU << ATMEL_LCDC_HFP_OFFSET) #define ATMEL_LCDC_LCDFRMCFG 0x0810 #define ATMEL_LCDC_LINEVAL (0x7ff << 0)
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1.5.3.4
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