am335x lcd not work

When you say LCD doesn't work, can you describe it more? LCD display is blank? Or kernel throws an error? Or nothing happens on LCD panel?

Did you make sure that, the LCD timing parameters which you added to driver is taking effect? Please note that you have to change the board-am335xevm.c file to specify the name of the lcd panel which you want to use.

Thanks,

Vaibhav

Vaibhav Hiremath：

thanks for your reply.

my lcd is 800*480. i have test the HSYNC VSYNC pclk .all of them is right. but the LCD display is blank.  i have changed the program for below:

//board-am335xevm.c

static const struct display_panel disp_panel = {
 WVGA,
 24,
 24,
 COLOR_ACTIVE,
};

//Daxx-fb.c

static struct da8xx_panel known_lcd_panels[] = {
 /* Sharp_LCD035Q3DG01*/
 [0] = {
  .name = "Sharp_LCD035Q3DG01",
  .width = 800,
  .height = 480,
  .hfp = 20,
  .hbp = 10,
  .hsw = 36,
  .vfp = 10,
  .vbp = 16,
  .vsw = 17,
  .pxl_clk = 33300000,
  .invert_pxl_clk = 0,
 },

I will be very thankful if u can tell me why when the kerel is start the serial is printf as below again and again:

00:01:57.109181725 UTC)
[  118.545288] init: untracked pid 453 exited
[  119.309783] pvrsrvkm: disagrees about version of symbol module_layout
[  119.338989] omaplfb: disagrees about version of symbol module_layout
[  125.245697] pvrsrvkm: disagrees about version of symbol module_layout
[  125.279632] omaplfb: disagrees about version of symbol module_layout
[  127.075683] request_suspend_state: wakeup (0->0) at 127072510382 (2000-01-01
00:02:05.653218590 UTC)

how can i solve the problem?? thank you very much.

yongliang huang said:

I will be very thankful if u can tell me why when the kerel is start the serial is printf as below again and again:

00:01:57.109181725 UTC)
[  118.545288] init: untracked pid 453 exited
[  119.309783] pvrsrvkm: disagrees about version of symbol module_layout
[  119.338989] omaplfb: disagrees about version of symbol module_layout
[  125.245697] pvrsrvkm: disagrees about version of symbol module_layout
[  125.279632] omaplfb: disagrees about version of symbol module_layout
[  127.075683] request_suspend_state: wakeup (0->0) at 127072510382 (2000-01-01
00:02:05.653218590 UTC)

This error is because the sgx kernel modules were not compiled against the kernel which is running. You need to compile the SGX modules against the kernel sources you are using. The easiest way to do this is to rebuild the full android filesystem.

hi:

thanks for you reply.now i rebuild the filesystem and kernel,the lcd is still blank, and the serial printf as belows:

root@android:/ # [    4.383392] Disabling lock debugging due to kernel taint
[    4.543609] omaplfb: OMAPLFBInitFBDev: Device 0: Unknown FB format
[    5.031250] init: untracked pid 61 exited
[    8.998962] init: untracked pid 104 exited
[   13.380523] init: untracked pid 119 exited
[   18.770111] init: untracked pid 126 exited
[   24.160858] init: untracked pid 133 exited
[   28.549530] init: untracked pid 140 exited
[   33.940765] init: untracked pid 147 exited
[   39.329406] init: untracked pid 154 exited
[   43.717651] init: untracked pid 161 exited
[   49.100830] init: untracked pid 168 exited
[   53.499908] init: untracked pid 175 exited
[   58.890594] init: untracked pid 182 exited
[   64.280517] init: untracked pid 189 exited
[   68.666534] init: untracked pid 196 exited

i will be very thankful if you tell why the printf     [4.543609] omaplfb: OMAPLFBInitFBDev: Device 0: Unknown FB format

thank you very much!

if you look at "Unknown FB format" error, you will see there is no 24 bits format. You can only use 32 or 16 bits.

static const struct display_panel disp_panel = {
 WVGA,
 24,
 24,
 COLOR_ACTIVE,
};

To

static const struct display_panel disp_panel = {
 WVGA,
 16,
 16,
 COLOR_ACTIVE,
};

for example.