From: Jan Glauber jglauber@cavium.com
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 (cherry picked from commit 38caa925ee67d2359f45a4a9cd1afa2e23a9eece) Signed-off-by: Vadim Lomovtsev Vadim.Lomovtsev@caviumnetworks.com --- drivers/i2c/busses/i2c-octeon-core.c | 23 ++++++++++++++--------- 1 file changed, 14 insertions(+), 9 deletions(-)
diff --git a/drivers/i2c/busses/i2c-octeon-core.c b/drivers/i2c/busses/i2c-octeon-core.c index 7d4df83..5e63b17 100644 --- 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) { - 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 */ @@ -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) - 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; @@ -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) - return -EAGAIN; - - ret = octeon_i2c_check_status(i2c, false); + return octeon_i2c_check_status(i2c, false);
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) - 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; @@ -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) - return -EAGAIN; - - ret = octeon_i2c_check_status(i2c, false); + return octeon_i2c_check_status(i2c, false);
err: return ret;