i2c: at91_i2c: Wait for TXRDY after sending the first byte

The driver must wait for TXRDY after each byte is pushed into
the i2c FIFO before pushing the next byte. Previously this was
not done for the first byte, causing a race condition with zeros
sometimes being sent for the next byte (which is typically the
first actual data byte).

Signed-off-by: Alan Ott <alan@softiron.com>
Reviewed-by: Heiko Schocher <hs@denx.de>
This commit is contained in:
Alan Ott 2017-11-28 22:25:23 -05:00 committed by Heiko Schocher
parent 50a69095cb
commit 0afbb0e1c0

View File

@ -72,6 +72,8 @@ static int at91_i2c_xfer_msg(struct at91_i2c_bus *bus, struct i2c_msg *msg)
} else {
writel(msg->buf[0], &reg->thr);
ret = at91_wait_for_xfer(bus, TWI_SR_TXRDY);
for (i = 1; !ret && (i < msg->len); i++) {
writel(msg->buf[i], &reg->thr);
ret = at91_wait_for_xfer(bus, TWI_SR_TXRDY);