i2c: octeon: Fix high-level controller status check

In case the high-level controller (HLC) is used the status code is
reported at a different location. Check that location after HLC
write operations if the ready bit is not set and return an appropriate
error code instead of always returning -EAGAIN.

Signed-off-by: Jan Glauber <jglauber@cavium.com>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>

diff --git a/drivers/i2c/busses/i2c-octeon-core.c b/drivers/i2c/busses/i2c-octeon-core.c
index 7d4df83..5e63b17 100644 (file)
--- a/drivers/i2c/busses/i2c-octeon-core.c
+++ b/drivers/i2c/busses/i2c-octeon-core.c
@@ -215,7 +215,16 @@ static int octeon_i2c_hlc_wait(struct octeon_i2c *i2c)
 
 static int octeon_i2c_check_status(struct octeon_i2c *i2c, int final_read)
 {
 
 static int octeon_i2c_check_status(struct octeon_i2c *i2c, int final_read)
 {

-       u8 stat = octeon_i2c_stat_read(i2c);
+       u8 stat;
+
+       /*
+        * This is ugly... in HLC mode the status is not in the status register
+        * but in the lower 8 bits of SW_TWSI.
+        */
+       if (i2c->hlc_enabled)
+               stat = __raw_readq(i2c->twsi_base + SW_TWSI(i2c));
+       else
+               stat = octeon_i2c_stat_read(i2c);

 
        switch (stat) {
        /* Everything is fine */
 
        switch (stat) {
        /* Everything is fine */


@@ -453,7 +462,7 @@ static int octeon_i2c_hlc_read(struct octeon_i2c *i2c, struct i2c_msg *msgs)
 
        cmd = __raw_readq(i2c->twsi_base + SW_TWSI(i2c));
        if ((cmd & SW_TWSI_R) == 0)
 
        cmd = __raw_readq(i2c->twsi_base + SW_TWSI(i2c));
        if ((cmd & SW_TWSI_R) == 0)

-               return -EAGAIN;
+               return octeon_i2c_check_status(i2c, false);

 
        for (i = 0, j = msgs[0].len - 1; i  < msgs[0].len && i < 4; i++, j--)
                msgs[0].buf[j] = (cmd >> (8 * i)) & 0xff;
 
        for (i = 0, j = msgs[0].len - 1; i  < msgs[0].len && i < 4; i++, j--)
                msgs[0].buf[j] = (cmd >> (8 * i)) & 0xff;


@@ -506,9 +515,7 @@ static int octeon_i2c_hlc_write(struct octeon_i2c *i2c, struct i2c_msg *msgs)
 
        cmd = __raw_readq(i2c->twsi_base + SW_TWSI(i2c));
        if ((cmd & SW_TWSI_R) == 0)
 
        cmd = __raw_readq(i2c->twsi_base + SW_TWSI(i2c));
        if ((cmd & SW_TWSI_R) == 0)

-               return -EAGAIN;
-
-       ret = octeon_i2c_check_status(i2c, false);
+               return octeon_i2c_check_status(i2c, false);

 
 err:
        return ret;
 
 err:
        return ret;


@@ -553,7 +560,7 @@ static int octeon_i2c_hlc_comp_read(struct octeon_i2c *i2c, struct i2c_msg *msgs
 
        cmd = __raw_readq(i2c->twsi_base + SW_TWSI(i2c));
        if ((cmd & SW_TWSI_R) == 0)
 
        cmd = __raw_readq(i2c->twsi_base + SW_TWSI(i2c));
        if ((cmd & SW_TWSI_R) == 0)

-               return -EAGAIN;
+               return octeon_i2c_check_status(i2c, false);

 
        for (i = 0, j = msgs[1].len - 1; i  < msgs[1].len && i < 4; i++, j--)
                msgs[1].buf[j] = (cmd >> (8 * i)) & 0xff;
 
        for (i = 0, j = msgs[1].len - 1; i  < msgs[1].len && i < 4; i++, j--)
                msgs[1].buf[j] = (cmd >> (8 * i)) & 0xff;


@@ -617,9 +624,7 @@ static int octeon_i2c_hlc_comp_write(struct octeon_i2c *i2c, struct i2c_msg *msg
 
        cmd = __raw_readq(i2c->twsi_base + SW_TWSI(i2c));
        if ((cmd & SW_TWSI_R) == 0)
 
        cmd = __raw_readq(i2c->twsi_base + SW_TWSI(i2c));
        if ((cmd & SW_TWSI_R) == 0)

-               return -EAGAIN;
-
-       ret = octeon_i2c_check_status(i2c, false);
+               return octeon_i2c_check_status(i2c, false);

 
 err:
        return ret;
 
 err:
        return ret;