Linux2.6.32 for Utu2440(5)

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In this chapter we will continue to migrate driver on LCD, first we want to get the LCD information.

LCD Info

From the LCD we could see “LTV350QV-F0E”, Search it on google and we know it’s SAMSUNG TFT 3.5-inch 320*240 LTV350QV-F0E lcd panel.
Its datasheet could be downloaded from:
http://www.datasheet-pdf.com/datasheet-html/L/T/V/LTV350QV-F0E_Samsung.pdf.html

TFT means ´╝łThin Film Transistor´╝ë.
Beware, the kernel we should choose is uImage_T1_F0E_320x240_ts, because we bought the Package 1 of the development board, they shipped us with Samsung screen .

Code Modification

Kernel configuration modification:

Device Drivers --->
	Graphics support --->
		<*> Support for frame buffer devices
			Support for buffer devices --->
				<*> S3C2410 LCD framebuffer support
		Backlight & LCD device sipport --->
			<*>Lowlevel LCD controls
		Display device support --->
			<*> Display panel/monitor support
		Console display driver support --->
			<*> Framebuffer Console support
			[*] Framebuffer Console Rotation
			[*] Select compiled-in fonts
			[*] VGA 8x8 font
			[*] VGA 8x16 font
			[*] Mini 4x6 font
			[*] Sparc console 8x16 font
		[*] Bootup logo --->
			--- Bootup logo
			[*] Standard 224-color Linux logo

arch/arm/mach-s3c2440/mach-smdk2440.c:

static struct s3c2410fb_display smdk2440_lcd_cfg __initdata = {
 
        .lcdcon5        = S3C2410_LCDCON5_FRM565 |
                          S3C2410_LCDCON5_INVVCLK |
                          S3C2410_LCDCON5_INVVLINE |
                          S3C2410_LCDCON5_INVVFRAME |
                        // S3C2410_LCDCON5_PWREN |
                          S3C2410_LCDCON5_HWSWP,
 
        .type           = S3C2410_LCDCON1_TFT,
 
        .width          = 320,    // 240,
        .height         = 240,    //320,
 
        .pixclock       = 100000,   //HCLK/10   166667,
        .xres           = 320,    //240,
        .yres           = 240,    //320,
        .bpp            = 16,
        .left_margin    = 17,     //HFPD+1     20,
        .right_margin   = 17,     //HBPD+1     8,
        .hsync_len      = 13,     //HSPW+1     4,
        .upper_margin   = 5,      //VBPD+1     8,
        .lower_margin   = 5,      //VFPD+1     7,
        .vsync_len      = 9,      //VSPW+1     4,
};

static struct s3c2410fb_mach_info smdk2440_fb_info __initdata = {
        .displays       = &smdk2440_lcd_cfg,
        .num_displays   =  1, 
        .default_display = 0,
 //#if 0
       
        .gpccon         = 0xaaaa56a9,    //0xaa940659,
        .gpccon_mask    = 0xffffffff,
        .gpcup          = 0xffffffff,    //0x0000ffff,
        .gpcup_mask     = 0xffffffff,
        .gpdcon         = 0xaaaaaaaa,    //0xaa84aaa0,
        .gpdcon_mask    = 0xffffffff,
        .gpdup          = 0xffffffff,    //0x0000faff,
        .gpdup_mask     = 0xffffffff,
//#endif 
        .lpcsel         = 0,     //((0xCE6) & ~7) | 1<<4,
};

Enable the lcd:

static struct platform_device *smdk2410_devices[] __initdata = {
&s3c_device_usb,
&s3c_device_lcd, 

arch/arm/mach-s3c2410/include/mach/regs-lcd.h:

#define S3C2410_LCDCON1_MMODE (0<<7)

drivers/video/s3c2410fb.c, after around line 52:

//LTV350QV_FOE_V0.0
 static void LTV350QV_Short_Delay(u_char time)
 {
  ndelay(150);
 }


#define LTV350QV_FOE 0x1d //device ID
typedef struct _LTV350qv_spi_data_{
unsigned char Device_ID; //ID of the device
unsigned int Index; //index of register
unsigned long Structure; //structure to be writed
}LTV350QV_SPI_Data;
//micro for LTV350QV_FOE
#define CS_H __raw_writel(__raw_readl(S3C2410_GPCDAT) |(1<< 8),S3C2410_GPCDAT)//MAKE_HIGH(LTV350QV_CS)
#define CS_L __raw_writel(__raw_readl(S3C2410_GPCDAT)&~(1<< 8),S3C2410_GPCDAT)//MAKE_LOW(LTV350QV_CS)
#define SCLK_H __raw_writel(__raw_readl(S3C2410_GPCDAT) |(1<< 9),S3C2410_GPCDAT)//MAKE_HIGH(LTV350QV_SCL)
#define SCLK_L __raw_writel(__raw_readl(S3C2410_GPCDAT)&~(1<< 9),S3C2410_GPCDAT)//MAKE_LOW(LTV350QV_SCL)
#define SDI_H __raw_writel(__raw_readl(S3C2410_GPCDAT) |(1<<10),S3C2410_GPCDAT)//MAKE_HIGH(LTV350QV_SDI)
#define SDI_L __raw_writel(__raw_readl(S3C2410_GPCDAT)&~(1<<10),S3C2410_GPCDAT)//MAKE_LOW(LTV350QV_SDI)
#define RST_H __raw_writel(__raw_readl(S3C2410_GPDDAT) |(1<< 0),S3C2410_GPDDAT)//MAKE_HIGH(LTV350QV_RST)
#define RST_L __raw_writel(__raw_readl(S3C2410_GPDDAT)&~(1<< 0),S3C2410_GPDDAT)//MAKE_LOW(LTV350QV_RST)
//
static void LTV350QV_Register_Write(LTV350QV_SPI_Data regdata)
{
u_char i,temp1;
u_int temp2;
u_long temp3;
unsigned long flags;
//write index
temp1=regdata.Device_ID<<2 | 0<<1 | 0<<0; //register index
temp2=regdata.Index;
temp3=(temp1<<24) | (temp2<<8);
local_irq_save(flags);
CS_L;
LTV350QV_Short_Delay(1);
for(i=0;i<24;i++)
{
SCLK_L;
if(temp3 & (1<<(31-i)) ) //if is H
SDI_H;
else
SDI_L;
LTV350QV_Short_Delay(1); //setup time
SCLK_H;
LTV350QV_Short_Delay(1); //hold time
}
CS_H;
LTV350QV_Short_Delay(5);
//write instruction
temp1=regdata.Device_ID<<2 | 1<<1 | 0<<0; //instruction
temp2=regdata.Structure;
temp3=(temp1<<24) | (temp2<<8);
CS_L;
LTV350QV_Short_Delay(1);
for(i=0;i<24;i++)
{
SCLK_L;
if(temp3 & (1<<(31-i)) ) //if is H
SDI_H;
else
SDI_L;
LTV350QV_Short_Delay(1);
SCLK_H;
LTV350QV_Short_Delay(1);
}
CS_H;
local_irq_restore(flags);
}
 
static void LTV350QV_Write(u_int index, u_int regdata)
{
LTV350QV_SPI_Data WriteData;
WriteData.Device_ID = LTV350QV_FOE;
WriteData.Index = index;
WriteData.Structure = regdata;
LTV350QV_Register_Write(WriteData);
}
 
static void LTV350QV_Power_ON(void)
{
LTV350QV_Write( 9, 0x0000);
mdelay(150);
LTV350QV_Write( 9, 0x4000);
LTV350QV_Write(10, 0x2000);
LTV350QV_Write( 9, 0x4055);
mdelay(550);
LTV350QV_Write( 1, 0x409d);
LTV350QV_Write( 2, 0x0204);
LTV350QV_Write( 3, 0x0100);
LTV350QV_Write( 4, 0x3000);
LTV350QV_Write( 5, 0x4003);
LTV350QV_Write( 6, 0x000a);
LTV350QV_Write( 7, 0x0021);
LTV350QV_Write( 8, 0x0c00);
LTV350QV_Write(10, 0x0103);
LTV350QV_Write(11, 0x0301);
LTV350QV_Write(12, 0x1f0f);
LTV350QV_Write(13, 0x1f0f);
LTV350QV_Write(14, 0x0707);
LTV350QV_Write(15, 0x0307);
LTV350QV_Write(16, 0x0707);
LTV350QV_Write(17, 0x0000);
LTV350QV_Write(18, 0x0004);
LTV350QV_Write(19, 0x0000);
mdelay(200);
LTV350QV_Write( 9, 0x4a55);
LTV350QV_Write( 5, 0x5003);
}
 
 
static void s3c2440fb_init_ltv350qv(void)
{
__raw_writel(0xaa9556a9, S3C2410_GPCCON); //Initialize VD[7:0],LCDVF[2:0],VM,VFRAME,VLINE,VCLK,LEND
//LCDVF[0],[1],[2]---output;VD[0],[1],[2]----output.
__raw_writel(0xffffffff, S3C2410_GPCUP); // Disable Pull-up register
LTV350QV_Power_ON() ; //init LCD model
__raw_writel(0xaaaaaaaa, S3C2410_GPDCON);
__raw_writel(0xffffffff, S3C2410_GPDUP);
// __raw_writel(3, S3C2410_LCDINTMSK); // MASK LCD Sub Interrupt
// __raw_writel(0, S3C2410_TPAL); // Disable Temp Palette
// __raw_writel(0, S3C2410_LPCSEL); // Disable LPC3600
}

Then add following sentense before the “return 0” of static int s3c2410fb_init_registers(struct fb_info *info):

s3c2440fb_init_ltv350qv();

Now recompile the kernel, you will see framebuffer OK.

Comment all of the function content of drivers/char/vt.c blank_screen_t(unsigned long dummy), this will disable the LCD’s display from closing.

Directly boot from tftp

Avoiding flash into the nand.


>tftp 30000000 uImage
dm9000 i/o: 0x18000300, id: 0x90000a46 
> bootm