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在 boar/embedsky/tq3358/evm.c 文件中有下面一个函数,问题见红色部分:
/*hxs amend 2012-9-12 RTC and BATERRY*/
void spl_board_init(void)
{
uchar pmic_status_reg = 0;
/* Configure the i2c0 pin mux */
enable_i2c0_pin_mux();
i2c_init(CONFIG_SYS_I2C_SPEED, CONFIG_SYS_I2C_SLAVE);
/*if (read_eeprom()) {
printf("read_eeprom() failure\n");
return;
}*/
#if 0
if (!strncmp("A335BONE", header.name, 8)) {
printd("evm.c/spl_board_init:: TPS65217_CHIP_PM = %d \n", TPS65217_CHIP_PM);
/* BeagleBone PMIC Code */
if (i2c_probe(TPS65217_CHIP_PM))
return;
printd("TPS659101 read DEVCTRL_REG = %d! \n", pmic_status_reg);
if (tps65217_reg_write(PROT_LEVEL_2, DEVCTRL_REG,
0X44, LDO_MASK))
printf("tps65217_reg_write DEVCTRL_REG failure\n");
printd("TPS659101 set DEVCTRL_REG success! \n");
if (tps65217_reg_read(DEVCTRL_REG, &pmic_status_reg))
return;
printd("TPS659101 read DEVCTRL_REG = %d! \n", pmic_status_reg);
/* Increase USB current limit to 1300mA */
if (tps65217_reg_write(PROT_LEVEL_NONE, POWER_PATH,
USB_INPUT_CUR_LIMIT_1300MA,
USB_INPUT_CUR_LIMIT_MASK))
printf("tps65217_reg_write failure\n");
/* Only perform PMIC configurations if board rev > A1 */
if (!strncmp(header.version, "00A1", 4))
return;
/* Set DCDC2 (MPU) voltage to 1.275V */
if (tps65217_voltage_update(DEFDCDC2,
DCDC_VOLT_SEL_1275MV)) {
printf("tps65217_voltage_update failure\n");
return;
}
/* Set LDO3, LDO4 output voltage to 3.3V */
if (tps65217_reg_write(PROT_LEVEL_2, DEFLS1,
LDO_VOLTAGE_OUT_3_3, LDO_MASK))
printf("tps65217_reg_write failure\n");
if (tps65217_reg_write(PROT_LEVEL_2, DEFLS2,
LDO_VOLTAGE_OUT_3_3, LDO_MASK))
printf("tps65217_reg_write failure\n");
if (!(pmic_status_reg & PWR_SRC_AC_BITMASK)) {
printf("No AC power, disabling frequency switch\n");
return;
}
/* Set MPU Frequency to 720MHz */
mpu_pll_config(MPUPLL_M_720);
}
else {
#else
if (1) {
#endif /* 1 */
set_tps659101();
}
}
这几行代码怎么理解,大括号怎么会把“#endif ”给扩进去了呢?
有解释吗? |
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