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| author | Luotao Fu <l.fu@pengutronix.de> | 2010-03-01 13:24:24 +0100 |
|---|---|---|
| committer | Ben Dooks <ben-linux@fluff.org> | 2010-03-07 22:10:09 +0000 |
| commit | ad0194e8d624df67a970a36e8ef9e61514e25553 (patch) | |
| tree | 0a6ca637423c97d98599d5e17a0f5af4bd03bc39 /drivers | |
| parent | 96eb7164e3c2f8c1b53118078e5c06f7c34c2d49 (diff) | |
| download | lwn-ad0194e8d624df67a970a36e8ef9e61514e25553.tar.gz lwn-ad0194e8d624df67a970a36e8ef9e61514e25553.zip | |
i2c-pnx: fix setting start/stop condition
The start/stop condtions are set in different places repetedly in the i2c-pnx
driver. Beside in i2c_pnx_start and i2c_pnx_stop the start/stop bit are also
set during the transfer of a i2c message in the master_xmit/rcv calls. This is
wrong since we can't set the start/stop condition during the transaction of a
single message any way. As a matter of fact, the driver will sometimes set both
the start and the stop bits at one time. This can be easily reproduced by
sending a simple read request like e.g
struct i2c_msg msgs[] = {
{ addr, 0, 1, buf },
{ addr, I2C_M_RD, offset, buf }
};
While processing the first message the i2c_pnx_master_xmit will set both the
start_bit and the stop_bit, which will eventually confuse the slave.
Fixed by remove setting start/stop condition from the transmit routines.
Signed-off-by: Luotao Fu <l.fu@pengutronix.de>
Signed-off-by: Ben Dooks <ben-linux@fluff.org>
Diffstat (limited to 'drivers')
| -rw-r--r-- | drivers/i2c/busses/i2c-pnx.c | 11 |
1 files changed, 0 insertions, 11 deletions
diff --git a/drivers/i2c/busses/i2c-pnx.c b/drivers/i2c/busses/i2c-pnx.c index 2b0bd0b042d6..9532dee6b580 100644 --- a/drivers/i2c/busses/i2c-pnx.c +++ b/drivers/i2c/busses/i2c-pnx.c @@ -172,12 +172,6 @@ static int i2c_pnx_master_xmit(struct i2c_pnx_algo_data *alg_data) /* We still have something to talk about... */ val = *alg_data->mif.buf++; - if (alg_data->mif.len == 1) { - val |= stop_bit; - if (!alg_data->last) - val |= start_bit; - } - alg_data->mif.len--; iowrite32(val, I2C_REG_TX(alg_data)); @@ -251,11 +245,6 @@ static int i2c_pnx_master_rcv(struct i2c_pnx_algo_data *alg_data) __func__); if (alg_data->mif.len == 1) { - /* Last byte, do not acknowledge next rcv. */ - val |= stop_bit; - if (!alg_data->last) - val |= start_bit; - /* * Enable interrupt RFDAIE (data in Rx fifo), * and disable DRMIE (need data for Tx) |