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/*
* This program is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
* GNU General Public License for more details.
*
* You should have received a copy of the GNU General Public License
* along with this program; if not, write to the Free Software
* Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
*/
#include <common.h>
#include <asm/arch/aspeed_i2c.h>
#ifdef CONFIG_DRIVER_ASPEED_I2C
void i2c_init (int speed, int slaveadd)
{
unsigned long SCURegister;
//I2C Reset
SCURegister = inl (SCU_BASE + SCU_RESET_CONTROL);
outl (SCURegister & ~(0x04), SCU_BASE + SCU_RESET_CONTROL);
//I2C Multi-Pin
SCURegister = inl (SCU_BASE + SCU_MULTIFUNCTION_PIN_CTL5_REG);
outl ((SCURegister | 0x30000), SCU_BASE + SCU_MULTIFUNCTION_PIN_CTL5_REG);
//Reset
outl (0, I2C_FUNCTION_CONTROL_REGISTER);
//Set AC Timing, we use fix AC timing for eeprom in u-boot
outl (AC_TIMING, I2C_AC_TIMING_REGISTER_1);
outl (0, I2C_AC_TIMING_REGISTER_2);
//Clear Interrupt
outl (ALL_CLEAR, I2C_INTERRUPT_STATUS_REGISTER);
//Enable Master Mode
outl (MASTER_ENABLE, I2C_FUNCTION_CONTROL_REGISTER);
//Enable Interrupt, STOP Interrupt has bug in AST2000
outl (0xAF, I2C_INTERRUPT_CONTROL_REGISTER);
//Set Slave address, should not use for eeprom
outl (slaveadd, I2C_DEVICE_ADDRESS_REGISTER);
}
static int i2c_read_byte (u8 devaddr, u16 regoffset, u8 * value, int alen)
{
int i2c_error = 0;
u32 status, count = 0;
//Start and Send Device Address
outl (devaddr, I2C_BYTE_BUFFER_REGISTER);
outl (MASTER_START_COMMAND | MASTER_TX_COMMAND, I2C_COMMAND_REGISTER);
//Wait Tx ACK
do {
status = (inl (I2C_INTERRUPT_STATUS_REGISTER) & (TX_ACK | TX_NACK));
count++;
if (count == LOOP_COUNT) {
i2c_error = 1;
printf ("Start and Send Device Address can't get ACK back\n");
return i2c_error;
}
} while (status != TX_ACK);
count = 0;
//Clear Interrupt
outl (ALL_CLEAR, I2C_INTERRUPT_STATUS_REGISTER);
//Check if address length equals to 16bits
if (alen != 1) {
//Send Device Register Offset (HIGH BYTE)
outl ((regoffset & 0xFF00) >> 8, I2C_BYTE_BUFFER_REGISTER);
outl (MASTER_TX_COMMAND, I2C_COMMAND_REGISTER);
//Wait Tx ACK
do {
status = (inl (I2C_INTERRUPT_STATUS_REGISTER) & (TX_ACK | TX_NACK));
count++;
if (count == LOOP_COUNT) {
i2c_error = 1;
printf ("Send Device Register Offset can't get ACK back\n");
return i2c_error;
}
} while (status != TX_ACK);
count = 0;
//Clear Interrupt
outl (ALL_CLEAR, I2C_INTERRUPT_STATUS_REGISTER);
}
//Send Device Register Offset(LOW)
outl (regoffset & 0xFF, I2C_BYTE_BUFFER_REGISTER);
outl (MASTER_TX_COMMAND, I2C_COMMAND_REGISTER);
//Wait Tx ACK
do {
status = (inl (I2C_INTERRUPT_STATUS_REGISTER) & (TX_ACK | TX_NACK));
count++;
if (count == LOOP_COUNT) {
i2c_error = 1;
printf ("Send Device Register Offset can't get ACK back\n");
return i2c_error;
}
} while (status != TX_ACK);
count = 0;
//Clear Interrupt
outl (ALL_CLEAR, I2C_INTERRUPT_STATUS_REGISTER);
//Start, Send Device Address + 1 (Read Mode), Receive Data
outl (devaddr + 1, I2C_BYTE_BUFFER_REGISTER);
outl (MASTER_START_COMMAND | MASTER_TX_COMMAND | MASTER_RX_COMMAND | RX_COMMAND_LIST, I2C_COMMAND_REGISTER);
//Wait Rx Done
do {
status = (inl (I2C_INTERRUPT_STATUS_REGISTER) & RX_DONE);
count++;
if (count == LOOP_COUNT) {
i2c_error = 1;
printf ("Can't get RX_DONE back\n");
return i2c_error;
}
} while (status != RX_DONE);
count = 0;
//Clear Interrupt
outl (ALL_CLEAR, I2C_INTERRUPT_STATUS_REGISTER);
//Enable Interrupt + Stop Interrupt
outl (0xBF, I2C_INTERRUPT_CONTROL_REGISTER);
//Issue Stop Command
outl (MASTER_STOP_COMMAND, I2C_COMMAND_REGISTER);
//Wait Stop
do {
status = (inl (I2C_INTERRUPT_STATUS_REGISTER) & STOP_DONE);
count++;
if (count == LOOP_COUNT) {
i2c_error = 1;
printf ("Can't get STOP back\n");
return i2c_error;
}
} while (status != STOP_DONE);
//Disable Stop Interrupt
outl (0xAF, I2C_INTERRUPT_CONTROL_REGISTER);
//Clear Interrupt
outl (ALL_CLEAR, I2C_INTERRUPT_STATUS_REGISTER);
//Read Received Data
*value = ((inl (I2C_BYTE_BUFFER_REGISTER) & 0xFF00) >> 8);
return i2c_error;
}
static int i2c_write_byte (u8 devaddr, u16 regoffset, u8 value, int alen)
{
int i2c_error = 0;
u32 status, count = 0;
//Start and Send Device Address
outl (devaddr, I2C_BYTE_BUFFER_REGISTER);
outl (MASTER_START_COMMAND | MASTER_TX_COMMAND, I2C_COMMAND_REGISTER);
//Wait Tx ACK
do {
status = (inl (I2C_INTERRUPT_STATUS_REGISTER) & (TX_ACK | TX_NACK));
count++;
if (status == TX_NACK) {
//Clear Interrupt
outl (ALL_CLEAR, I2C_INTERRUPT_STATUS_REGISTER);
//Re-send Start and Send Device Address while NACK return
outl (devaddr, I2C_BYTE_BUFFER_REGISTER);
outl (MASTER_START_COMMAND | MASTER_TX_COMMAND, I2C_COMMAND_REGISTER);
}
else {
if (count == LOOP_COUNT) {
i2c_error = 1;
printf ("Start and Send Device Address can't get ACK back\n");
return i2c_error;
}
}
} while (status != TX_ACK);
count = 0;
//Clear Interrupt
outl (ALL_CLEAR, I2C_INTERRUPT_STATUS_REGISTER);
//Check if address length equals to 16bits
if (alen != 1) {
//Send Device Register Offset (HIGH BYTE)
outl ((regoffset & 0xFF00) >> 8, I2C_BYTE_BUFFER_REGISTER);
outl (MASTER_TX_COMMAND, I2C_COMMAND_REGISTER);
//Wait Tx ACK
do {
status = (inl (I2C_INTERRUPT_STATUS_REGISTER) & (TX_ACK | TX_NACK));
count++;
if (count == LOOP_COUNT) {
i2c_error = 1;
printf ("Send Device Register Offset can't get ACK back\n");
return i2c_error;
}
} while (status != TX_ACK);
count = 0;
//Clear Interrupt
outl (ALL_CLEAR, I2C_INTERRUPT_STATUS_REGISTER);
}
//Send Device Register Offset
outl (regoffset & 0xFF, I2C_BYTE_BUFFER_REGISTER);
outl (MASTER_TX_COMMAND, I2C_COMMAND_REGISTER);
//Wait Tx ACK
do {
status = (inl (I2C_INTERRUPT_STATUS_REGISTER) & (TX_ACK | TX_NACK));
count++;
if (count == LOOP_COUNT) {
i2c_error = 1;
printf ("Send Device Register Offset can't get ACK back\n");
return i2c_error;
}
} while (status != TX_ACK);
count = 0;
//Clear Interrupt
outl (ALL_CLEAR, I2C_INTERRUPT_STATUS_REGISTER);
//Send Device Register Value
outl (value, I2C_BYTE_BUFFER_REGISTER);
outl (MASTER_TX_COMMAND, I2C_COMMAND_REGISTER);
//Wait Tx ACK
do {
status = (inl (I2C_INTERRUPT_STATUS_REGISTER) & (TX_ACK | TX_NACK));
count++;
if (count == LOOP_COUNT) {
i2c_error = 1;
printf ("Send Device Register Value can't get ACK back\n");
return i2c_error;
}
} while (status != TX_ACK);
count = 0;
//Clear Interrupt
outl (ALL_CLEAR, I2C_INTERRUPT_STATUS_REGISTER);
//Enable Interrupt + Stop Interrupt
outl (0xBF, I2C_INTERRUPT_CONTROL_REGISTER);
//Issue Stop Command
outl (MASTER_STOP_COMMAND, I2C_COMMAND_REGISTER);
//Wait Stop
do {
status = (inl (I2C_INTERRUPT_STATUS_REGISTER) & STOP_DONE);
count++;
if (count == LOOP_COUNT) {
i2c_error = 1;
printf ("Can't get STOP back\n");
return i2c_error;
}
} while (status != STOP_DONE);
//Disable Stop Interrupt
outl (0xAF, I2C_INTERRUPT_CONTROL_REGISTER);
//Clear Interrupt
outl (ALL_CLEAR, I2C_INTERRUPT_STATUS_REGISTER);
return i2c_error;
}
int i2c_probe (uchar chip)
{
//Suppose IP is always on chip
int res = 0;
return res;
}
int i2c_read (uchar device_addr, uint register_offset, int alen, uchar * buffer, int len)
{
int i;
if ((alen == 1) && ((register_offset + len) > 256)) {
printf ("Register index overflow\n");
}
for (i = 0; i < len; i++) {
if (i2c_read_byte (device_addr, register_offset + i, &buffer[i], alen)) {
printf ("I2C read: I/O error\n");
i2c_init (CONFIG_SYS_I2C_SPEED, CONFIG_SYS_I2C_SLAVE);
return 1;
}
}
return 0;
}
int i2c_write (uchar device_addr, uint register_offset, int alen, uchar * buffer, int len)
{
int i;
if ((alen == 1) && ((register_offset + len) > 256)) {
printf ("Register index overflow\n");
}
for (i = 0; i < len; i++) {
if (i2c_write_byte (device_addr, register_offset + i, buffer[i], alen)) {
printf ("I2C read: I/O error\n");
i2c_init (CONFIG_SYS_I2C_SPEED, CONFIG_SYS_I2C_SLAVE);
return 1;
}
}
return 0;
}
#endif /* CONFIG_DRIVER_ASPEED_I2C */
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