i2c-eg20t: Separate error processing

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>

diff --git a/drivers/i2c/busses/i2c-eg20t.c b/drivers/i2c/busses/i2c-eg20t.c
index 38e44d9..cb29686 100644 (file)
--- a/drivers/i2c/busses/i2c-eg20t.c
+++ b/drivers/i2c/busses/i2c-eg20t.c
@@ -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;
                }
@@ -428,30 +443,48 @@ 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]);
+       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 (pch_i2c_wait_for_xfer_complete(adap) != 0)
-                               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]);
 
-                       if (pch_i2c_getack(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;
+                       }
+                       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);
-       } else {
+       /* check if this is the last message */
+       if (last)
                pch_i2c_stop(adap);
-               return -EIO;
-       }
+       else
+               pch_i2c_repstart(adap);
 
        pch_dbg(adap, "return=%d\n", 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);
+               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);
+               /* Dummy read */
+               for (loop = 1, read_index = 0; loop < length; loop++) {
+                       buf[read_index] = ioread32(p + PCH_I2CDR);
 
-                               if (loop != 1)
-                                       read_index++;
+                       if (loop != 1)
+                               read_index++;
 
-                               if (pch_i2c_wait_for_xfer_complete(adap) != 0) {
-                                       pch_i2c_stop(adap);
-                                       return -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;
                                }
-                       }       /* end for */
+                       } else { /* wait-event timeout */
+                               pch_i2c_stop(adap);
+                               return -ETIME;
+                       }
 
-                       pch_i2c_sendnack(adap);
+               }       /* end for */
 
-                       buf[read_index] = ioread32(p + PCH_I2CDR);
+               pch_i2c_sendnack(adap);
 
-                       if (length != 1)
-                               read_index++;
+               buf[read_index] = ioread32(p + PCH_I2CDR); /* Read final - 1 */
 
-                       if (pch_i2c_wait_for_xfer_complete(adap) == 0) {
-                               if (last)
-                                       pch_i2c_stop(adap);
-                               else
-                                       pch_i2c_repstart(adap);
+               if (length != 1)
+                       read_index++;
 
-                               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;
                }
-       } 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;