static int pch_i2c_wait_for_check_xfer(struct i2c_algo_pch_data *adap)
{
long ret;
ret = wait_event_timeout(pch_event,
(adap->pch_event_flag != 0), msecs_to_jiffies(1000));
if (!ret) {
pch_err(adap, "%s:wait-event timeout\n", __func__);
adap->pch_event_flag = 0;
pch_i2c_stop(adap);
pch_i2c_init(adap);
return -ETIMEDOUT;
}
if (adap->pch_event_flag & I2C_ERROR_MASK) {
pch_err(adap, "Lost Arbitration\n");
adap->pch_event_flag = 0;
pch_clrbit(adap->pch_base_address, PCH_I2CSR, I2CMAL_BIT);
pch_clrbit(adap->pch_base_address, PCH_I2CSR, I2CMIF_BIT);
pch_i2c_init(adap);
return -EAGAIN;
}
adap->pch_event_flag = 0;
if (pch_i2c_getack(adap)) {
pch_dbg(adap, "Receive NACK for slave address"
"setting\n");
return -EIO;
}
return 0;
}
/**
* pch_i2c_wait_for_bus_idle() - check the status of bus.
* @adap: Pointer to struct i2c_algo_pch_data.
* @timeout: waiting time counter (ms).
*/
static s32 pch_i2c_wait_for_bus_idle(struct i2c_algo_pch_data *adap,
s32 timeout)
{
void __iomem *p = adap->pch_base_address;
int schedule = 0;
unsigned long end = jiffies + msecs_to_jiffies(timeout);
while (ioread32(p + PCH_I2CSR) & I2CMBB_BIT) {
if (time_after(jiffies, end)) {
pch_dbg(adap, "I2CSR = %x\n", ioread32(p + PCH_I2CSR));
pch_err(adap, "%s: Timeout Error.return%d\n",
__func__, -ETIME);
pch_i2c_init(adap);
return -ETIME;
}
if (!schedule)
/* Retry after some usecs */
udelay(5);
else
/* Wait a bit more without consuming CPU */
usleep_range(20, 1000);
schedule = 1;
}
return 0;
}
/**
* pch_i2c_writebytes() - write data to I2C bus in normal mode
* @i2c_adap: Pointer to the struct i2c_adapter.
* @last: specifies whether last message or not.
* In the case of compound mode it will be 1 for last message,
* otherwise 0.
* @first: specifies whether first message or not.
* 1 for first message otherwise 0.
*/
static s32 pch_i2c_writebytes(struct i2c_adapter *i2c_adap,
struct i2c_msg *msgs, u32 last, u32 first)
{
struct i2c_algo_pch_data *adap = i2c_adap->algo_data;
u8 *buf;
u32 length;
u32 addr;
u32 addr_2_msb;
u32 addr_8_lsb;
s32 wrcount;
s32 rtn;
void __iomem *p = adap->pch_base_address;
length = msgs->len;
buf = msgs->buf;
addr = msgs->addr;
/* enable master tx */
pch_setbit(adap->pch_base_address, PCH_I2CCTL, I2C_TX_MODE);
pch_dbg(adap, "I2CCTL = %x msgs->len = %d\n", ioread32(p + PCH_I2CCTL),
length);
if (first) {
if (pch_i2c_wait_for_bus_idle(adap, BUS_IDLE_TIMEOUT) == -ETIME)
return -ETIME;
}
if (msgs->flags & I2C_M_TEN) {
addr_2_msb = ((addr & I2C_MSB_2B_MSK) >> 7) & 0x06;
iowrite32(addr_2_msb | TEN_BIT_ADDR_MASK, p + PCH_I2CDR);
if (first)
pch_i2c_start(adap);
rtn = pch_i2c_wait_for_xfer_complete(adap);
if (rtn == 0) {
if (pch_i2c_getack(adap)) {
pch_dbg(adap, "Receive NACK for slave address"
"setting\n");
return -EIO;
}
addr_8_lsb = (addr & I2C_ADDR_MSK);
iowrite32(addr_8_lsb, p + PCH_I2CDR);
} else if (rtn == -EIO) { /* Arbitration Lost */
pch_err(adap, "Lost Arbitration\n");
pch_clrbit(adap->pch_base_address, PCH_I2CSR,
I2CMAL_BIT);
pch_clrbit(adap->pch_base_address, PCH_I2CSR,
I2CMIF_BIT);
pch_i2c_init(adap);
return -EAGAIN;
} else { /* wait-event timeout */
pch_i2c_stop(adap);
return -ETIME;
}
} else {
/**
* pch_i2c_getack() - to confirm ACK/NACK
* @adap: Pointer to struct i2c_algo_pch_data.
*/
static s32 pch_i2c_getack(struct i2c_algo_pch_data *adap)
{
u32 reg_val;
void __iomem *p = adap->pch_base_address;
reg_val = ioread32(p + PCH_I2CSR) & PCH_GETACK;
if (reg_val != 0) {
pch_err(adap, "return%d\n", -EPROTO);
return -EPROTO;
}
return 0;
}
/**
* pch_i2c_wait_for_xfer_complete() - initiates a wait for the tx complete event
* @adap: Pointer to struct i2c_algo_pch_data.
*/
static s32 pch_i2c_wait_for_xfer_complete(struct i2c_algo_pch_data *adap)
{
long ret;
ret = wait_event_timeout(pch_event,
(adap->pch_event_flag != 0), msecs_to_jiffies(1000));
if (ret == 0) {
pch_err(adap, "timeout: %x\n", adap->pch_event_flag);
adap->pch_event_flag = 0;
return -ETIMEDOUT;
}
if (adap->pch_event_flag & I2C_ERROR_MASK) {
pch_err(adap, "error bits set: %x\n", adap->pch_event_flag);
adap->pch_event_flag = 0;
return -EIO;
}
adap->pch_event_flag = 0;
return 0;
}
/**
* pch_i2c_wait_for_bus_idle() - check the status of bus.
* @adap: Pointer to struct i2c_algo_pch_data.
* @timeout: waiting time counter (us).
*/
static s32 pch_i2c_wait_for_bus_idle(struct i2c_algo_pch_data *adap,
s32 timeout)
{
void __iomem *p = adap->pch_base_address;
/* MAX timeout value is timeout*1000*1000nsec */
ktime_t ns_val = ktime_add_ns(ktime_get(), timeout*1000*1000);
do {
if ((ioread32(p + PCH_I2CSR) & I2CMBB_BIT) == 0)
break;
msleep(20);
} while (ktime_lt(ktime_get(), ns_val));
pch_dbg(adap, "I2CSR = %x\n", ioread32(p + PCH_I2CSR));
if (timeout == 0) {
pch_err(adap, "%s: Timeout Error.return%d\n", __func__, -ETIME);
return -ETIME;
}
return 0;
}
