Am 01.06.2010 16:04, schrieb Reinhard Meyer (-VC): > Hi, Dear Reinhard Meyer,
> has anyone started or completed work on an I2C driver for AP7000x? No ... > > If not, I am at least going to make SOFT I2C defines to read VPD from an > At24C64 EEPROM. But I've working soft-i2c here. There are still some other examples in u-boot how to interface a at24xx eeprom. custom board config file: ---8<--- /* i2c definitions */ #define CONFIG_SOFT_I2C #if defined(CONFIG_SOFT_I2C) #define DEBUG_I2C #ifndef __ASSEMBLY__ #include <asm/arch/portmux.h> #define MEDUCORE_SDA_PIN 6 #define MEDUCORE_SCL_PIN 7 #define I2C_ACTIVE portmux_select_gpio(PORTMUX_PORT_A, (1<<MEDUCORE_SDA_PIN), PORTMUX_DIR_OUTPUT|PORTMUX_INIT_LOW) #define I2C_TRISTATE portmux_select_gpio(PORTMUX_PORT_A, (1<<MEDUCORE_SDA_PIN), PORTMUX_DIR_INPUT|PORTMUX_OPEN_DRAIN) #define I2C_READ pio_get_input_value(GPIO_PIN_PA(MEDUCORE_SDA_PIN)) #define I2C_SDA(bit) pio_set_output_value(GPIO_PIN_PA(MEDUCORE_SDA_PIN), bit) #define I2C_SCL(bit) pio_set_output_value(GPIO_PIN_PA(MEDUCORE_SCL_PIN), bit) #endif #define I2C_DELAY udelay(3) /* TODO needs testing */ #define I2C_SOFT_DECLARATIONS #define CONFIG_SYS_I2C_SLAVE 0x0 #define CONFIG_SYS_I2C_SPEED 100000 /* TODO needs testing */ #define CONFIG_CMD_I2C #endif --->8--- and in our custom board implementation (only snippet): ---8<--- @@ -29,6 +29,8 @@ #include <asm/arch/hmatrix.h> #include <asm/arch/portmux.h> +#include <i2c.h> + DECLARE_GLOBAL_DATA_PTR; /* @@ -71,6 +73,38 @@ static const struct sdram_config sdram_config = { int board_early_init_f(void) { + unsigned char val = 0xFF; + unsigned char version = 0x00; + int ret = -1; // assume error + + // first select SCL gpio + portmux_select_gpio(PORTMUX_PORT_A, (1<<MEDUCORE_SCL_PIN), PORTMUX_DIR_OUTPUT|PORTMUX_INIT_LOW); + // initialize i2c + i2c_init(1000, 0x27); + // check for precedence of port multiplexer + ret = i2c_probe(0x27); + if ( ret != 0 ) { + gd->flags |= GD_FLG_POSTFAIL; + goto out; + } + + ret |= i2c_write(0x27, 0x06, 1, &val, 1); // set GPPU to FF + ret |= i2c_write(0x27, 0x01, 1, &val, 1); // set IPOL to FF (invert palaritiy) + if ( ret != 0 ) { + gd->flags |= GD_FLG_POSTFAIL; + goto out; + } + + ret = i2c_read(0x27, 0x09, 1, &version, 1); // read in the version value + if ( ret != 0 ) { + gd->flags |= GD_FLG_POSTFAIL; + goto out; + } + // version can be used from here --->8--- regards Andreas Bießmann _______________________________________________ U-Boot mailing list U-Boot@lists.denx.de http://lists.denx.de/mailman/listinfo/u-boot