Spotted by Dean Capindale.
Systems that support open-drain GPIO properly are allowed provide an empty I2C_TRISTATE define. However, this means that we need to be careful not to drive SDA low when the slave is expected to respond.
This patch adds a missing I2C_SDA(1) to read_byte() required to tristate the SDA line on systems that support open-drain GPIO.
Signed-off-by: Haavard Skinnemoen haavard.skinnemoen@atmel.com --- common/soft_i2c.c | 1 + 1 files changed, 1 insertions(+), 0 deletions(-)
diff --git a/common/soft_i2c.c b/common/soft_i2c.c index c5d7e20..5ef7f30 100644 --- a/common/soft_i2c.c +++ b/common/soft_i2c.c @@ -252,6 +252,7 @@ static uchar read_byte(int ack) * Read 8 bits, MSB first. */ I2C_TRISTATE; + I2C_SDA(1); data = 0; for(j = 0; j < 8; j++) { I2C_SCL(0);