Forums

Hi Keldy,

In u-boot i2c0 is enabled by default, you can go through "read_eeprom()" API for usage.

can i really use <i2c.h> header file to enable i2c1 as well? any changes needed?

Yes, you have to add i2c.h

i2c1 sould be register in the simillar lines as that of i2c0.

* Do proper pinmuxing

* enable i2c1 clocks

* i2c_int()

Note: In software I2C instances are starting from 1 instead of 0 (HW)

Regards

AnilKumar

Please mark this Forum post as answered via the Verify Answer button below if it helps answer your question.  Thanks!

Also you need to setup pin-mux for i2c1 pins.

so you need to setup

1. i2c1 clocks

2. i2c1 pin-mux

3. proper i2c1 base address to be used by omap-i2c driver

4. verify that the omap-i2c driver supports multi-bus and use it accordingly

Regards

Gururaja

Hi All,

I build a i2c1 function inside u-boot code, ("board-support/u-boot-2011.09-psp04.06.00.02/board/ti/am335x/evm.c"), in this case, i plan to communicate with i2c port expander (tca6416) with chip address 0x20, communication speed 400k.

___________________________________________________________________

void i2c1(void)
{
 u32 val;
 val = __raw_readl(CONF_SPI0_D1);            //pin_mux i2c1_sda
 val = (val & 0xFFFFFFF1 | 0x2);
 __raw_writel(val, CONF_SPI0_D1);

 val = __raw_readl(CONF_SPI0_CS0);            //pin_mux i2c1_scl
 val = (val & 0xFFFFFFF1 | 0x2);
 __raw_writel(val, CONF_SPI0_CS0);

 i2c_init(400000, 0x20); //i2c speed 400k, i2c port expander (tca6416) chip address 0x20
 
 printf("sending value = 0xFF\n");           //write value
 i2c_write(0x20, 0x06, 1, 0xFF, 1);
 
 uchar read_val;        //read value
 printf("reading value :");
 i2c_read(0x20, 0x06, 1, &read_val, 1);
 printf("%d\n", read_val); 
}

___________________________________________________________________

am i correct? is the i2c_init(), i2c_write(), i2c_read() functions applicable for i2c1 ?

Thanks & Regards

Keldy  

I dont think thats enough. By default u-boot i2c driver will be working for i2c-0 instance. so you need to switch it to i2c-1 instance.

Also look at board-support/u-boot-2011.09-psp04.06.00.02/board/ti/am335x/mux.c on how i2c0 pin-mux is done. 

Have you set i2c1 clocks (controller clocks & not i2c device clocks). for this look at board-support/u-boot-2011.09-psp04.06.00.02/board/ti/am335x/pll.c

Hi,

in "board-support/u-boot-2011.09-psp04.06.00.02/board/ti/am335x/mux.c"

i have changed: PULLUDEN to PULLUDDIS (because i use external pull-up)

static struct module_pin_mux i2c1_pin_mux[] = {
 {OFFSET(spi0_d1), (MODE(2) | RXACTIVE | PULLUDDIS | SLEWCTRL)}, /* I2C_DATA */
 {OFFSET(spi0_cs0), (MODE(2) | RXACTIVE | PULLUDDIS | SLEWCTRL)}, /* I2C_SCLK */
 {-1},
};

and i have add new function:

void enable_i2c1_pin_mux(void)
{
 configure_module_pin_mux(i2c1_pin_mux);
}

in "board-support/u-boot-2011.09-psp04.06.00.02/board/ti/am335x/evm.c"

void i2c1(void)
{

enable_i2c1_pin_mux(); //set pin mux
 
 /* enable clock i2c1 */
 __raw_writel(0x2, CM_PER_I2C1_CLKCTRL);
 while (__raw_readl(CM_PER_I2C1_CLKCTRL) != 0x2);
 
 i2c_init(400000, 0x20); //i2c speed 400k, chip address 0x20
 
 printf("sending value = 0xFF\n");           //write value
 i2c_write(0x20, 0x06, 1, 0xFF, 1);
 
 uchar read_val;        //read value
 printf("reading value :");
 i2c_read(0x20, 0x06, 1, &read_val, 1);
 printf("%d\n", read_val); 
 
}

how i switch u-boot i2c driver to i2c-1 instance?

Thanks & Regards

Keldy

Hi Keldy,

Replace this line
 i2c_init(400000, 0x20); //i2c speed 400k, chip address 0x20

with
 i2c_init(400000, 2); //i2c speed 400k, chip id 2 /* instance 1 */

Regards

AnilKumar

Please mark this Forum post as answered via the Verify Answer button below if it helps answer your question.  Thanks!

Hi,

my u-boot hang while execute the i2c1() function, the i2c_write() cause the u-boot hang.

void i2c1 (void)

{

 enable_i2c1_pin_mux();
 
 /* enable clock i2c1 */
 __raw_writel(0x2, CM_PER_I2C1_CLKCTRL);
 while (__raw_readl(CM_PER_I2C1_CLKCTRL) != 0x2);
 
 i2c_init(400000, 2); //i2c speed 400k, chip address 0x20
 
 printf("sending value = 0xFF\n");           //write value
 i2c_write(0x20, 0x06, 1, 0xFF, 1);         //-----------------------------------------------------------------------------this line cause the u-boot hang
 uchar read_val;        //read value
 printf("reading value :");
 i2c_read(0x20, 0x06, 1, &read_val, 1);
 printf("%d\n", read_val); 
}

Any wrong with my code, what i have miss to configure?

Thanks & Regards

Keldy

Hi Keldy,

Looking at the board/ti/am335x/evm.c , only  pinmuxing and i2c_init is done did you add both these in
board_init() function itself? are you sure the i2c speed for i2c1 is 400000?

Thx,

--Prabhakar Lad

Hi Keldy,

Remove "enable clock i2c1" code from your9 part. Because all the I2C clocks are enabled in u-boot in "pll_init()"

You have to call your API (i2c1) after pll_init() call.

Regards

AnilKumar

Please mark this Forum post as answered via the Verify Answer button below if it helps answer your question.  Thanks!

Hi,

in "/board-support/u-boot-2011.09-psp04.06.00.02/board/ti/am335x/evm.c

under function: s_init(void) :

void s_init(void)
{
 /* Can be removed as A8 comes up with L2 enabled */
 l2_cache_enable();

 /* WDT1 is already running when the bootloader gets control
  * Disable it to avoid "random" resets
  */
 __raw_writel(0xAAAA, WDT_WSPR);
 while(__raw_readl(WDT_WWPS) != 0x0);
 __raw_writel(0x5555, WDT_WSPR);
 while(__raw_readl(WDT_WWPS) != 0x0);

#ifdef CONFIG_SPL_BUILD
 /* Setup the PLLs and the clocks for the peripherals */
 pll_init();
 i2c1();  ---------------------------------------------------------------- my API i2c1();

The u-boot no hang anymore, but seen like the u-boot didn't execute i2c1(), because it didn't printf the message inside the i2c1(void) function.

do i need to call the function s_init() inside board_init() function ?

Thanks & Regard

Keldy

Hi Keldy,

Can you add next to config_am335x_ddr();? I think console is not initialized at your step.

Regards

AnilKumar

Please mark this Forum post as answered via the Verify Answer button below if it helps answer your question.  Thanks!

Hi,

void s_init(void)
{
 /* Can be removed as A8 comes up with L2 enabled */
 l2_cache_enable();

 /* WDT1 is already running when the bootloader gets control
  * Disable it to avoid "random" resets
  */
 __raw_writel(0xAAAA, WDT_WSPR);
 while(__raw_readl(WDT_WWPS) != 0x0);
 __raw_writel(0x5555, WDT_WSPR);
 while(__raw_readl(WDT_WWPS) != 0x0);

#ifdef CONFIG_SPL_BUILD
 /* Setup the PLLs and the clocks for the peripherals */
 pll_init();
 
 /* UART softreset */
 u32 regVal;
 u32 uart_base = DEFAULT_UART_BASE;

 enable_uart0_pin_mux();
 /* IA Motor Control Board has default console on UART3*/
 /* XXX: This is before we've probed / set board_id */
 if (board_id == IA_BOARD) {
  uart_base = UART3_BASE;
 }

 regVal = __raw_readl(uart_base + UART_SYSCFG_OFFSET);
 regVal |= UART_RESET;
 __raw_writel(regVal, (uart_base + UART_SYSCFG_OFFSET) );
 while ((__raw_readl(uart_base + UART_SYSSTS_OFFSET) &
   UART_CLK_RUNNING_MASK) != UART_CLK_RUNNING_MASK);

 /* Disable smart idle */
 regVal = __raw_readl((uart_base + UART_SYSCFG_OFFSET));
 regVal |= UART_SMART_IDLE_EN;
 __raw_writel(regVal, (uart_base + UART_SYSCFG_OFFSET));

 /* Initialize the Timer */
 init_timer();

 preloader_console_init();

 config_am335x_ddr();
 i2c1(); ----------------------------------------------------------------------------my i2c1 API
#endif
}

the result still the same, the u-boot didn't execute the i2c1().

Thanks & Regards

Keldy

HI All;

if your paritcular i2c need to be worked means,

which bus you are using, need to initialize in i2c_init function last line okay!

bus_initialized[current_bus] = X; // X is the bus number

It' will work!!!!!!!!!!

Regards

santosh vastrad