[U-Boot] [PATCH 2/2] xilinx_xiic: Fix transfer initialisation

Marek Vasut marex at denx.de
Tue Jun 25 11:33:25 UTC 2019


On 6/25/19 11:59 AM, Melin Tomas wrote:
> 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: 9656eeebf3f1dd05376c4c923797369746d9a618

This should be 12 character commit SHA1 and the commit subject.

> Signed-off-by: Tomas Melin <tomas.melin at vaisala.com>
> ---
>  drivers/i2c/xilinx_xiic.c | 9 +++++++++
>  1 file changed, 9 insertions(+)
> 
> diff --git a/drivers/i2c/xilinx_xiic.c b/drivers/i2c/xilinx_xiic.c
> index e4ca0ab936..4c2d0edf48 100644
> --- a/drivers/i2c/xilinx_xiic.c
> +++ b/drivers/i2c/xilinx_xiic.c
> @@ -267,6 +267,15 @@ static void xiic_reinit(struct xilinx_xiic_priv *priv)
>  static int xilinx_xiic_xfer(struct udevice *dev, struct i2c_msg *msg, int nmsgs)
>  {
>  	int ret = 0;
> +	struct xilinx_xiic_priv *priv = dev_get_priv(dev);

Keep this sorted in reverse xmas tree order.

> +	ret = wait_for_bit_8(priv->base + XIIC_SR_REG_OFFSET,
> +			     XIIC_SR_BUS_BUSY_MASK, false, 3000, true);

Why 3 seconds wait ?

> +	if (ret)
> +		return ret;
> +
> +	xiic_reinit(priv);
>  
>  	for (; nmsgs > 0; nmsgs--, msg++) {
>  		if (msg->flags & I2C_M_RD)
> 


-- 
Best regards,
Marek Vasut


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