[PATCH v2] mdio: aspeed: Fix "Link is Down" issue

[Andrew Lunn]

On Thu, Nov 25, 2021 at 10:44:32AM +0800, Dylan Hung wrote:
> The issue happened randomly in runtime.  The message "Link is Down" is
> popped but soon it recovered to "Link is Up".
> 
> The "Link is Down" results from the incorrect read data for reading the
> PHY register via MDIO bus.  The correct sequence for reading the data
> shall be:
> 1. fire the command
> 2. wait for command done (this step was missing)
> 3. wait for data idle
> 4. read data from data register
> 
> Fixes: f160e99462c6 ("net: phy: Add mdio-aspeed")
> Cc: stable at vger.kernel.org
> Reviewed-by: Joel Stanley <joel at jms.id.au>
> Signed-off-by: Dylan Hung <dylan_hung at aspeedtech.com>

Reviewed-by: Andrew Lunn <andrew at lunn.ch>

    Andrew