From: Luotao Fu Date: Mon, 1 Mar 2010 12:24:24 +0000 (+0100) Subject: i2c-pnx: fix setting start/stop condition X-Git-Url: https://git.stricted.de/?a=commitdiff_plain;h=ad0194e8d624df67a970a36e8ef9e61514e25553;p=GitHub%2Fexynos8895%2Fandroid_kernel_samsung_universal8895.git 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 Signed-off-by: Ben Dooks --- 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)