MLK-14237 video: mxsfb: fb1 maybe access when fb0 in blank state

The overlay framebuffer fb1 access maybe accessed when fb0
is in the blank state in which all the lcd clocks have been
disabled.

Signed-off-by: Fancy Fang <chen.fang@nxp.com>

diff --git a/drivers/video/fbdev/mxsfb.c b/drivers/video/fbdev/mxsfb.c
index 25ad8db..cf8a13f 100644 (file)
--- a/drivers/video/fbdev/mxsfb.c
+++ b/drivers/video/fbdev/mxsfb.c
@@ -1818,6 +1818,7 @@ static int overlayfb_set_par(struct fb_info *info)
 {
        int size, bpp;
        struct mxsfb_layer *ofb = (struct mxsfb_layer*)info->par;
+       struct mxsfb_info  *fbi = ofb->fbi;
        struct fb_var_screeninfo *var = &ofb->ol_fb->var;
 
        bpp = var->bits_per_pixel;
@@ -1827,6 +1828,15 @@ static int overlayfb_set_par(struct fb_info *info)
        if (ofb->video_mem_size < size)
                return -EINVAL;
 
+       if (!lock_fb_info(fbi->fb_info))
+               return -EINVAL;
+
+       if (fbi->cur_blank != FB_BLANK_UNBLANK) {
+               clk_enable_pix(fbi);
+               clk_enable_axi(fbi);
+               clk_enable_disp_axi(fbi);
+       }
+
        if (ofb->blank_state == FB_BLANK_UNBLANK)
                ofb->ops->disable(ofb);
 
@@ -1835,6 +1845,14 @@ static int overlayfb_set_par(struct fb_info *info)
        if (ofb->blank_state == FB_BLANK_UNBLANK)
                ofb->ops->enable(ofb);
 
+       if (fbi->cur_blank != FB_BLANK_UNBLANK) {
+               clk_disable_disp_axi(fbi);
+               clk_disable_axi(fbi);
+               clk_disable_pix(fbi);
+       }
+
+       unlock_fb_info(fbi->fb_info);
+
        if ((var->activate & FB_ACTIVATE_FORCE) &&
            (var->activate & FB_ACTIVATE_MASK) == FB_ACTIVATE_NOW)
                var->activate = FB_ACTIVATE_NOW;
@@ -1845,10 +1863,20 @@ static int overlayfb_set_par(struct fb_info *info)
 static int overlayfb_blank(int blank, struct fb_info *info)
 {
        struct mxsfb_layer *ofb = (struct mxsfb_layer*)info->par;
+       struct mxsfb_info  *fbi  = ofb->fbi;
 
        if (ofb->blank_state == blank)
                return 0;
 
+       if (!lock_fb_info(fbi->fb_info))
+               return -EINVAL;
+
+       if (fbi->cur_blank != FB_BLANK_UNBLANK) {
+               clk_enable_pix(fbi);
+               clk_enable_axi(fbi);
+               clk_enable_disp_axi(fbi);
+       }
+
        switch (blank) {
        case FB_BLANK_POWERDOWN:
        case FB_BLANK_VSYNC_SUSPEND:
@@ -1861,6 +1889,14 @@ static int overlayfb_blank(int blank, struct fb_info *info)
                break;
        }
 
+       if (fbi->cur_blank != FB_BLANK_UNBLANK) {
+               clk_disable_disp_axi(fbi);
+               clk_disable_axi(fbi);
+               clk_disable_pix(fbi);
+       }
+
+       unlock_fb_info(fbi->fb_info);
+
        ofb->blank_state = blank;
 
        return 0;
@@ -1876,6 +1912,16 @@ static int overlayfb_pan_display(struct fb_var_screeninfo *var,
 
        init_completion(&fbi->flip_complete);
 
+       if (!lock_fb_info(fbi->fb_info))
+               return -EINVAL;
+
+       if (fbi->cur_blank != FB_BLANK_UNBLANK) {
+               unlock_fb_info(fbi->fb_info);
+               return -EINVAL;
+       }
+
+       unlock_fb_info(fbi->fb_info);
+
        bytes_offset = info->fix.line_length * var->yoffset;
        writel(info->fix.smem_start + bytes_offset,
               fbi->base + LCDC_AS_NEXT_BUF);