From d3826fb052af9e6df22abaefb1b0c7496e469f9e Mon Sep 17 00:00:00 2001 From: Melin Tomas Date: Fri, 28 Jun 2019 12:08:40 +0000 Subject: [PATCH] xilinx_xiic: Fix transfer initialisation 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") hs: Fixed DOS line endings added missing '\n' Fixed git commit description style Signed-off-by: Tomas Melin --- 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..5ce0f869c7 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\n"); + + 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); -- 2.39.5