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i2c-eg20t: Separate error processing

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Error processing for NACK or wait-event must be precessed separately.
So divide wait-event error processing into NACK-receiving and timeout.
Add arbitration lost processing.

Signed-off-by: Tomoya MORINAGA <tomoya-linux@dsn.lapis-semi.com>
Signed-off-by: Ben Dooks <ben-linux@fluff.org>
This commit is contained in:
Tomoya MORINAGA 2011-10-12 13:13:03 +09:00 committed by Ben Dooks
parent c249ac207f
commit 12bd314651
1 changed files with 122 additions and 65 deletions
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187
drivers/i2c/busses/i2c-eg20t.c
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@ -391,6 +391,7 @@ static s32 pch_i2c_writebytes(struct i2c_adapter *i2c_adap,
u32 addr_2_msb;
u32 addr_8_lsb;
s32 wrcount;
s32 rtn;
void __iomem *p = adap->pch_base_address;
length = msgs->len;
@ -413,11 +414,25 @@ static s32 pch_i2c_writebytes(struct i2c_adapter *i2c_adap,
iowrite32(addr_2_msb | TEN_BIT_ADDR_MASK, p + PCH_I2CDR);
if (first)
pch_i2c_start(adap);
if (pch_i2c_wait_for_xfer_complete(adap) == 0 &&
pch_i2c_getack(adap) == 0) {
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 {
} 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;
}
@ -428,31 +443,49 @@ static s32 pch_i2c_writebytes(struct i2c_adapter *i2c_adap,
pch_i2c_start(adap);
}
if ((pch_i2c_wait_for_xfer_complete(adap) == 0) &&
(pch_i2c_getack(adap) == 0)) {
for (wrcount = 0; wrcount < length; ++wrcount) {
/* write buffer value to I2C data register */
iowrite32(buf[wrcount], p + PCH_I2CDR);
pch_dbg(adap, "writing %x to Data register\n",
buf[wrcount]);
if (pch_i2c_wait_for_xfer_complete(adap) != 0)
return -ETIME;
if (pch_i2c_getack(adap))
return -EIO;
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;
}
/* check if this is the last message */
if (last)
pch_i2c_stop(adap);
else
pch_i2c_repstart(adap);
} else {
pch_i2c_stop(adap);
return -EIO;
} 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);
return -EAGAIN;
} else { /* wait-event timeout */
return -ETIME;
}
for (wrcount = 0; wrcount < length; ++wrcount) {
/* write buffer value to I2C data register */
iowrite32(buf[wrcount], p + PCH_I2CDR);
pch_dbg(adap, "writing %x to Data register\n", buf[wrcount]);
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;
}
pch_clrbit(adap->pch_base_address, PCH_I2CSR,
I2CMCF_BIT);
pch_clrbit(adap->pch_base_address, PCH_I2CSR,
I2CMIF_BIT);
} else { /* wait-event timeout */
return -ETIME;
}
}
/* check if this is the last message */
if (last)
pch_i2c_stop(adap);
else
pch_i2c_repstart(adap);
pch_dbg(adap, "return=%d\n", wrcount);
return wrcount;
@ -512,6 +545,7 @@ static s32 pch_i2c_readbytes(struct i2c_adapter *i2c_adap, struct i2c_msg *msgs,
u32 addr_2_msb;
u32 addr_8_lsb;
void __iomem *p = adap->pch_base_address;
s32 rtn;
length = msgs->len;
buf = msgs->buf;
@ -585,56 +619,79 @@ static s32 pch_i2c_readbytes(struct i2c_adapter *i2c_adap, struct i2c_msg *msgs,
if (first)
pch_i2c_start(adap);
if ((pch_i2c_wait_for_xfer_complete(adap) == 0) &&
(pch_i2c_getack(adap) == 0)) {
pch_dbg(adap, "return %d\n", 0);
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;
}
} 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);
return -EAGAIN;
} else { /* wait-event timeout */
return -ETIME;
}
if (length == 0) {
pch_i2c_stop(adap);
ioread32(p + PCH_I2CDR); /* Dummy read needs */
if (length == 0) {
pch_i2c_stop(adap);
ioread32(p + PCH_I2CDR); /* Dummy read needs */
count = length;
} else {
int read_index;
int loop;
pch_i2c_sendack(adap);
/* Dummy read */
for (loop = 1, read_index = 0; loop < length; loop++) {
buf[read_index] = ioread32(p + PCH_I2CDR);
if (loop != 1)
read_index++;
if (pch_i2c_wait_for_xfer_complete(adap) != 0) {
pch_i2c_stop(adap);
return -ETIME;
}
} /* end for */
pch_i2c_sendnack(adap);
count = length;
} else {
int read_index;
int loop;
pch_i2c_sendack(adap);
/* Dummy read */
for (loop = 1, read_index = 0; loop < length; loop++) {
buf[read_index] = ioread32(p + PCH_I2CDR);
if (length != 1)
if (loop != 1)
read_index++;
if (pch_i2c_wait_for_xfer_complete(adap) == 0) {
if (last)
pch_i2c_stop(adap);
else
pch_i2c_repstart(adap);
buf[read_index++] = ioread32(p + PCH_I2CDR);
count = read_index;
} else {
count = -ETIME;
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;
}
} else { /* wait-event timeout */
pch_i2c_stop(adap);
return -ETIME;
}
} /* end for */
pch_i2c_sendnack(adap);
buf[read_index] = ioread32(p + PCH_I2CDR); /* Read final - 1 */
if (length != 1)
read_index++;
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;
}
} else { /* wait-event timeout */
pch_i2c_stop(adap);
return -ETIME;
}
} else {
count = -ETIME;
pch_i2c_stop(adap);
if (last)
pch_i2c_stop(adap);
else
pch_i2c_repstart(adap);
buf[read_index++] = ioread32(p + PCH_I2CDR); /* Read Final */
count = read_index;
}
return count;