Prior to starting a new transfer, conditionally wait for bus to not
be busy.
Reinitialise controller as otherwise operation is not stable.
For reference, see linux kernel commit: 9656eeebf3f1 ("i2c: Revert
"i2c: xiic: Do not reset controller before every transfer"")
Signed-off-by: Tomas Melin <tomas.me...@vaisala.com>
---
Changes in v2:
- Change variable declaration order
- Change timeout to 3ms
Changes in v3:
- Change timeout to 1000ms
- Add print in case of timeout
drivers/i2c/xilinx_xiic.c | 12 ++++++++++++
1 file changed, 12 insertions(+)
diff --git a/drivers/i2c/xilinx_xiic.c b/drivers/i2c/xilinx_xiic.c
index e4ca0ab936..afb5f21b75 100644
--- a/drivers/i2c/xilinx_xiic.c
+++ b/drivers/i2c/xilinx_xiic.c
@@ -266,8 +266,20 @@ static void xiic_reinit(struct xilinx_xiic_priv *priv)
static int xilinx_xiic_xfer(struct udevice *dev, struct i2c_msg *msg, int
nmsgs)
{
+ struct xilinx_xiic_priv *priv = dev_get_priv(dev);
int ret = 0;
+ ret = wait_for_bit_8(priv->base + XIIC_SR_REG_OFFSET,
+ XIIC_SR_BUS_BUSY_MASK, false, 1000, true);
+
+ if (ret == -ETIMEDOUT)
+ dev_err(dev, "timeout waiting for bus not busy condition");
+
+ if (ret)
+ return ret;
+
+ xiic_reinit(priv);
+
for (; nmsgs > 0; nmsgs--, msg++) {
if (msg->flags & I2C_M_RD)
ret = xilinx_xiic_read_common(dev, msg, nmsgs);
--
2.17.2
_______________________________________________
U-Boot mailing list
U-Boot@lists.denx.de
https://lists.denx.de/listinfo/u-boot
