7d258451d3
commit b6ad6261d27708567b309fdb3102b12c42a070cc upstream.
Experimentation shows that PHY detect might fail when the code attempts
MDIO bus read immediately after clock enable. Add delay to stabilize the
clock before bus access.
PHY detect failure started to show after commit 7590fc6f80ac ("net:
mdio: Demote probed message to debug print") that removed coincidental
delay between clock enable and bus access.
10ms is meant to match the time it take to send the probed message over
UART at 115200 bps. This might be a far overshoot.
Fixes: 23a890d493e3 ("net: mdio: Add the reset function for IPQ MDIO driver")
Signed-off-by: Baruch Siach <baruch.siach@siklu.com>
Reviewed-by: Andrew Lunn <andrew@lunn.ch>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Linux kernel
============
There are several guides for kernel developers and users. These guides can
be rendered in a number of formats, like HTML and PDF. Please read
Documentation/admin-guide/README.rst first.
In order to build the documentation, use ``make htmldocs`` or
``make pdfdocs``. The formatted documentation can also be read online at:
https://www.kernel.org/doc/html/latest/
There are various text files in the Documentation/ subdirectory,
several of them using the Restructured Text markup notation.
Please read the Documentation/process/changes.rst file, as it contains the
requirements for building and running the kernel, and information about
the problems which may result by upgrading your kernel.