Re: [PATCH net-next 4/7] net: phy: bcm84881: use phy_read_mmd_poll_timeout() to simplify the code

[Andrew Lunn <andrew@lunn.ch>]

On Fri, Mar 20, 2020 at 12:39:07AM +0800, Dejin Zheng wrote:
> use phy_read_mmd_poll_timeout() to replace the poll codes for
> simplify the code in bcm84881_wait_init() function.
> 
> Signed-off-by: Dejin Zheng <zhengdejin5@gmail.com>
> ---
>  drivers/net/phy/bcm84881.c | 24 ++++++------------------
>  1 file changed, 6 insertions(+), 18 deletions(-)
> 
> diff --git a/drivers/net/phy/bcm84881.c b/drivers/net/phy/bcm84881.c
> index 14d55a77eb28..c916bd0f6afa 100644
> --- a/drivers/net/phy/bcm84881.c
> +++ b/drivers/net/phy/bcm84881.c
> @@ -22,26 +22,14 @@ enum {
>  
>  static int bcm84881_wait_init(struct phy_device *phydev)
>  {
> -	unsigned int tries = 20;
>  	int ret, val;
>  
> -	do {
> -		val = phy_read_mmd(phydev, MDIO_MMD_PMAPMD, MDIO_CTRL1);
> -		if (val < 0) {
> -			ret = val;
> -			break;
> -		}
> -		if (!(val & MDIO_CTRL1_RESET)) {
> -			ret = 0;
> -			break;
> -		}
> -		if (!--tries) {
> -			ret = -ETIMEDOUT;
> -			break;
> -		}
> -		msleep(100);
> -	} while (1);
> -
> +	ret = phy_read_mmd_poll_timeout(val, val < 0 ||
> +					!(val & MDIO_CTRL1_RESET), 100000,

It would be good if the "val < 0" was not here. What the user is
really interested in is !(val & MDIO_CTRL1_RESET). "val < 0" is the
error handling for phy_read_mmd(). This would look a lot nicer if that
error handling was inside phy_read_mmd_poll_timeout() and ret would
already contain the error from phy_read_mmd(). Not sure you can do
this and still make use of readx_poll_timeout().

     Andrew