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#include <device/smbus_def.h>
#define SMBGSTATUS 0xe0
#define SMBGCTL 0xe2
#define SMBHSTADDR 0xe4
#define SMBHSTDAT 0xe6
#define SMBHSTCMD 0xe8
#define SMBHSTFIFO 0xe9
#define SMBUS_TIMEOUT (100*1000*10)
#define SMBUS_STATUS_MASK 0xfbff
static inline void smbus_delay(void)
{
outb(0x80, 0x80);
}
static int smbus_wait_until_ready(unsigned smbus_io_base)
{
unsigned long loops;
loops = SMBUS_TIMEOUT;
do {
unsigned short val;
smbus_delay();
val = inw(smbus_io_base + SMBGSTATUS);
if ((val & 0x800) == 0) {
break;
}
if(loops == (SMBUS_TIMEOUT / 2)) {
outw(inw(smbus_io_base + SMBGSTATUS),
smbus_io_base + SMBGSTATUS);
}
} while(--loops);
return loops?0:SMBUS_WAIT_UNTIL_READY_TIMEOUT;
}
static int smbus_wait_until_done(unsigned smbus_io_base)
{
unsigned long loops;
loops = SMBUS_TIMEOUT;
do {
unsigned short val;
smbus_delay();
val = inw(smbus_io_base + SMBGSTATUS);
if (((val & 0x8) == 0) | ((val & 0x0037) != 0)) {
break;
}
} while(--loops);
return loops?0:SMBUS_WAIT_UNTIL_DONE_TIMEOUT;
}
static int do_smbus_recv_byte(unsigned smbus_io_base, unsigned device)
{
unsigned global_status_register;
unsigned byte;
if (smbus_wait_until_ready(smbus_io_base) < 0) {
return SMBUS_WAIT_UNTIL_READY_TIMEOUT;
}
/* setup transaction */
/* disable interrupts */
outw(inw(smbus_io_base + SMBGCTL) & ~((1<<10)|(1<<9)|(1<<8)|(1<<4)), smbus_io_base + SMBGCTL);
/* set the device I'm talking too */
outw(((device & 0x7f) << 1) | 1, smbus_io_base + SMBHSTADDR);
/* set the command/address... */
outb(0, smbus_io_base + SMBHSTCMD);
/* set up for a send byte */
outw((inw(smbus_io_base + SMBGCTL) & ~7) | (0x1), smbus_io_base + SMBGCTL);
/* clear any lingering errors, so the transaction will run */
/* Do I need to write the bits to a 1 to clear an error? */
outw(inw(smbus_io_base + SMBGSTATUS), smbus_io_base + SMBGSTATUS);
/* set the data word...*/
outw(0, smbus_io_base + SMBHSTDAT);
/* start the command */
outw((inw(smbus_io_base + SMBGCTL) | (1 << 3)), smbus_io_base + SMBGCTL);
/* poll for transaction completion */
if (smbus_wait_until_done(smbus_io_base) < 0) {
return SMBUS_WAIT_UNTIL_DONE_TIMEOUT;
}
global_status_register = inw(smbus_io_base + SMBGSTATUS);
/* read results of transaction */
byte = inw(smbus_io_base + SMBHSTDAT) & 0xff;
if ((global_status_register & SMBUS_STATUS_MASK) != (1 << 4)) {
return SMBUS_ERROR;
}
return byte;
}
static int do_smbus_send_byte(unsigned smbus_io_base, unsigned device, unsigned value)
{
unsigned global_status_register;
if (smbus_wait_until_ready(smbus_io_base) < 0) {
return SMBUS_WAIT_UNTIL_READY_TIMEOUT;
}
/* setup transaction */
/* disable interrupts */
outw(inw(smbus_io_base + SMBGCTL) & ~((1<<10)|(1<<9)|(1<<8)|(1<<4)), smbus_io_base + SMBGCTL);
/* set the device I'm talking too */
outw(((device & 0x7f) << 1) | 0, smbus_io_base + SMBHSTADDR);
/* set the command/address... */
outb(0, smbus_io_base + SMBHSTCMD);
/* set up for a send byte */
outw((inw(smbus_io_base + SMBGCTL) & ~7) | (0x1), smbus_io_base + SMBGCTL);
/* clear any lingering errors, so the transaction will run */
/* Do I need to write the bits to a 1 to clear an error? */
outw(inw(smbus_io_base + SMBGSTATUS), smbus_io_base + SMBGSTATUS);
/* set the data word...*/
outw(value, smbus_io_base + SMBHSTDAT);
/* start the command */
outw((inw(smbus_io_base + SMBGCTL) | (1 << 3)), smbus_io_base + SMBGCTL);
/* poll for transaction completion */
if (smbus_wait_until_done(smbus_io_base) < 0) {
return SMBUS_WAIT_UNTIL_DONE_TIMEOUT;
}
global_status_register = inw(smbus_io_base + SMBGSTATUS);
if ((global_status_register & SMBUS_STATUS_MASK) != (1 << 4)) {
return SMBUS_ERROR;
}
return 0;
}
static int do_smbus_read_byte(unsigned smbus_io_base, unsigned device, unsigned address)
{
unsigned global_status_register;
unsigned byte;
if (smbus_wait_until_ready(smbus_io_base) < 0) {
return SMBUS_WAIT_UNTIL_READY_TIMEOUT;
}
/* setup transaction */
/* disable interrupts */
outw(inw(smbus_io_base + SMBGCTL) & ~((1<<10)|(1<<9)|(1<<8)|(1<<4)), smbus_io_base + SMBGCTL);
/* set the device I'm talking too */
outw(((device & 0x7f) << 1) | 1, smbus_io_base + SMBHSTADDR);
/* set the command/address... */
outb(address & 0xFF, smbus_io_base + SMBHSTCMD);
/* set up for a byte data read */
outw((inw(smbus_io_base + SMBGCTL) & ~7) | (0x2), smbus_io_base + SMBGCTL);
/* clear any lingering errors, so the transaction will run */
/* Do I need to write the bits to a 1 to clear an error? */
outw(inw(smbus_io_base + SMBGSTATUS), smbus_io_base + SMBGSTATUS);
/* clear the data word...*/
outw(0, smbus_io_base + SMBHSTDAT);
/* start the command */
outw((inw(smbus_io_base + SMBGCTL) | (1 << 3)), smbus_io_base + SMBGCTL);
/* poll for transaction completion */
if (smbus_wait_until_done(smbus_io_base) < 0) {
return SMBUS_WAIT_UNTIL_DONE_TIMEOUT;
}
global_status_register = inw(smbus_io_base + SMBGSTATUS);
/* read results of transaction */
byte = inw(smbus_io_base + SMBHSTDAT) & 0xff;
if ((global_status_register & SMBUS_STATUS_MASK) != (1 << 4)) {
return SMBUS_ERROR;
}
return byte;
}
static int do_smbus_write_byte(unsigned smbus_io_base, unsigned device, unsigned address, unsigned char val)
{
unsigned global_status_register;
if (smbus_wait_until_ready(smbus_io_base) < 0) {
return SMBUS_WAIT_UNTIL_READY_TIMEOUT;
}
/* setup transaction */
/* disable interrupts */
outw(inw(smbus_io_base + SMBGCTL) & ~((1<<10)|(1<<9)|(1<<8)|(1<<4)), smbus_io_base + SMBGCTL);
/* set the device I'm talking too */
outw(((device & 0x7f) << 1) | 0, smbus_io_base + SMBHSTADDR);
outb(address & 0xFF, smbus_io_base + SMBHSTCMD);
/* set up for a byte data write */ /* FIXME */
outw((inw(smbus_io_base + SMBGCTL) & ~7) | (0x2), smbus_io_base + SMBGCTL);
/* clear any lingering errors, so the transaction will run */
/* Do I need to write the bits to a 1 to clear an error? */
outw(inw(smbus_io_base + SMBGSTATUS), smbus_io_base + SMBGSTATUS);
/* write the data word...*/
outw(val, smbus_io_base + SMBHSTDAT);
/* start the command */
outw((inw(smbus_io_base + SMBGCTL) | (1 << 3)), smbus_io_base + SMBGCTL);
/* poll for transaction completion */
if (smbus_wait_until_done(smbus_io_base) < 0) {
return SMBUS_WAIT_UNTIL_DONE_TIMEOUT;
}
global_status_register = inw(smbus_io_base + SMBGSTATUS);
if ((global_status_register & SMBUS_STATUS_MASK) != (1 << 4)) {
return SMBUS_ERROR;
}
return 0;
}
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