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1. static int s3c_fb_blank(int blank_mode, struct fb_info *info)
2. {
3. struct s3c_fb_win *win = info->par;
4. struct s3c_fb *sfb = win->parent;
5. unsigned int index = win->index;
6. u32 wincon;
7. printk("lj:s3c_fb_blank:blank mode:%d\n",blank_mode);
8. dev_dbg(sfb->dev, "blank mode %d\n", blank_mode);
9. pm_runtime_get_sync(sfb->dev);
10. wincon = readl(sfb->regs + sfb->variant.wincon + (index * 4));
11. switch (blank_mode) {
12. case FB_BLANK_POWERDOWN:
13. wincon &= ~WINCONx_ENWIN;
14. sfb->enabled &= ~(1 << index);
15. /* fall through to FB_BLANK_NORMAL */
16. case FB_BLANK_NORMAL:
17. /* disable the DMA and display 0x0 (black) */
18. shadow_protect_win(win, 1);
19. dump_stack();
20. writel(WINxMAP_MAP | WINxMAP_MAP_COLOUR(0x00),//liujia  disable the black screen
21. sfb->regs + sfb->variant.winmap + (index * 4));
22. shadow_protect_win(win, 0);
23. break;
24. case FB_BLANK_UNBLANK:
25. shadow_protect_win(win, 1);
26. writel(0x0, sfb->regs + sfb->variant.winmap + (index * 4));
27. shadow_protect_win(win, 0);
28. wincon |= WINCONx_ENWIN;
29. sfb->enabled |= (1 << index);
30. break;
31. case FB_BLANK_VSYNC_SUSPEND:
32. case FB_BLANK_HSYNC_SUSPEND:
33. default:
34. pm_runtime_put_sync(sfb->dev);
35. return 1;
36. }
37. shadow_protect_win(win, 1);
38. writel(wincon, sfb->regs + sfb->variant.wincon + (index * 4));
39. shadow_protect_win(win, 0);
40. /* Check the enabled state to see if we need to be running the
41. * main LCD interface, as if there are no active windows then
42. * it is highly likely that we also do not need to output
43. * anything.
44. */
45. /* We could do something like the following code, but the current
46. * system of using framebuffer events means that we cannot make
47. * the distinction between just window 0 being inactive and all
48. * the windows being down.
49. *
50. * s3c_fb_enable(sfb, sfb->enabled ? 1 : 0);
51. */
52. /* we're stuck with this until we can do something about overriding
53. * the power control using the blanking event for a single fb.
54. */
55. if (index == sfb->pdata->default_win) {
56. shadow_protect_win(win, 1);
57. s3c_fb_enable(sfb, blank_mode != FB_BLANK_POWERDOWN ? 1 : 0);
58. shadow_protect_win(win, 0);
59. }
60. pm_runtime_put_sync(sfb->dev);
61. return 0;
62. }

1. case FB_BLANK_NORMAL:
2. /* disable the DMA and display 0x0 (black) */
3. shadow_protect_win(win, 1);
4. dump_stack();
5. writel(WINxMAP_MAP | WINxMAP_MAP_COLOUR(0x00),//liujia  disable the black screen
6. sfb->regs + sfb->variant.winmap + (index * 4));
7. shadow_protect_win(win, 0);
8. break;

1. <7>[   61.285759] lj:s3c_fb_blank:blank mode:1
2. <7>[   61.285772] lj:shadow_protect_win:1
3. <7>[   61.285816] [<80013120>] (unwind_backtrace+0x0/0xec) from [<801af0b8>] (s3c_fb_blank+0x84/0x180)
4. <7>[   61.285835] [<801af0b8>] (s3c_fb_blank+0x84/0x180) from [<801a2bcc>] (fb_blank+0x3c/0x68)
5. <7>[   61.285852] [<801a2bcc>] (fb_blank+0x3c/0x68) from [<801a9690>] (fbcon_blank+0x118/0x260)
6. <7>[   61.285875] [<801a9690>] (fbcon_blank+0x118/0x260) from [<801c7594>] (do_blank_screen+0x1b8/0x258)
7. <7>[   61.285892] [<801c7594>] (do_blank_screen+0x1b8/0x258) from [<801c884c>] (console_callback+0xe4/0x114)
8. <7>[   61.285909] [<801c884c>] (console_callback+0xe4/0x114) from [<8002e12c>] (process_one_work+0x1e8/0x318)
9. <7>[   61.285927] [<8002e12c>] (process_one_work+0x1e8/0x318) from [<800301c0>] (worker_thread+0x1b4/0x2b4)
10. <7>[   61.285947] [<800301c0>] (worker_thread+0x1b4/0x2b4) from [<80033438>] (kthread+0x88/0x94)
11. <7>[   61.285969] [<80033438>] (kthread+0x88/0x94) from [<8000ec20>] (kernel_thread_exit+0x0/0x8)
12. <7>[   61.285979] lj:shadow_protect_win:0
13. <7>[   61.285984] lj:shadow_protect_win:1
14. <7>[   61.285990] lj:shadow_protect_win:0
15. <7>[   61.285995] lj:shadow_protect_win:1
16. <7>[   61.286001] lj:s3c_fb_set_par
17. <7>[   61.286005] lj:shadow_protect_win:0