Resent as plain text this time. Sorry to those that got this twice.
On Mon, Mar 23, 2020 at 11:10 AM Dejin Zheng <zhengdej...@gmail.com> wrote:
>
> use phy_read_poll_timeout() to replace the poll codes for
> simplify lan87xx_read_status() function.
>
> Suggested-by: Andrew Lunn <and...@lunn.ch>
> Reviewed-by: Florian Fainelli <f.faine...@gmail.com>
> Signed-off-by: Dejin Zheng <zhengdej...@gmail.com>
> ---
> v6 -> v7:
> - adapt to a newly added parameter sleep_before_read.
> v5 -> v6:
> - no changed.
> v4 -> v5:
> - add msleep before phy_read_poll_timeout() to keep the
> code more similar
> v3 -> v4:
> - add this patch by Andrew's suggestion. Thanks Andrew!
>
> drivers/net/phy/smsc.c | 16 +++++-----------
> 1 file changed, 5 insertions(+), 11 deletions(-)
>
> diff --git a/drivers/net/phy/smsc.c b/drivers/net/phy/smsc.c
> index b73298250793..93da7d3d0954 100644
> --- a/drivers/net/phy/smsc.c
> +++ b/drivers/net/phy/smsc.c
> @@ -112,8 +112,6 @@ static int lan87xx_read_status(struct phy_device *phydev)
> int err = genphy_read_status(phydev);
>
> if (!phydev->link && priv->energy_enable) {
> - int i;
> -
> /* Disable EDPD to wake up PHY */
> int rc = phy_read(phydev, MII_LAN83C185_CTRL_STATUS);
> if (rc < 0)
> @@ -125,15 +123,11 @@ static int lan87xx_read_status(struct phy_device
> *phydev)
> return rc;
>
> /* Wait max 640 ms to detect energy */
> - for (i = 0; i < 64; i++) {
> - /* Sleep to allow link test pulses to be sent */
> - msleep(10);
> - rc = phy_read(phydev, MII_LAN83C185_CTRL_STATUS);
> - if (rc < 0)
> - return rc;
> - if (rc & MII_LAN83C185_ENERGYON)
> - break;
> - }
> + phy_read_poll_timeout(phydev, MII_LAN83C185_CTRL_STATUS, rc,
> + rc & MII_LAN83C185_ENERGYON, 10000,
> + 640000, true);
> + if (rc < 0)
> + return rc;
>
> /* Re-enable EDPD */
> rc = phy_read(phydev, MII_LAN83C185_CTRL_STATUS);
> --
> 2.25.0
This patch causes the kernel log to be spammed with the following when
Ethernet cable is not connected:
SMSC LAN8710/LAN8720 2188000.ethernet-1:00: lan87xx_read_status failed: -110
It still seems to work but I think that is only a fluke.
The "if (rc < 0)" is not actually checking the return value of
phy_read_poll_timeout but is looking at the value of the register
read. I don't think rc will ever be negative in this case. If you
change the code to "rc = phy_read_poll_timeout(...)" so that it
actually checks the error then the function will behave differently
than before. The original code would only return an error if phy_read
returned an error. On a timeout it just continued. So the "if" could
be changed to "if (rc < 0 && rc != -ETIMEDOUT)". But you will still
get the extra messages in the log that were not there before.
Kevin
