tree 57494784e7f165aa9f445ecef2d202cb2f04e662
parent e7b9fb4f545b1f7885e7c642643828f93d3d79c9
author Quentin Schulz <quentin.schulz@bootlin.com> 1542996111 +0100
committer David S. Miller <davem@davemloft.net> 1543041280 -0800

net: phy: mscc: fix deadlock in vsc85xx_default_config

The vsc85xx_default_config function called in the vsc85xx_config_init
function which is used by VSC8530, VSC8531, VSC8540 and VSC8541 PHYs
mistakenly calls phy_read and phy_write in-between phy_select_page and
phy_restore_page.

phy_select_page and phy_restore_page actually take and release the MDIO
bus lock and phy_write and phy_read take and release the lock to write
or read to a PHY register.

Let's fix this deadlock by using phy_modify_paged which handles
correctly a read followed by a write in a non-standard page.

Fixes: 6a0bfbbe20b0 ("net: phy: mscc: migrate to phy_select/restore_page functions")
Signed-off-by: Quentin Schulz <quentin.schulz@bootlin.com>
Reviewed-by: Andrew Lunn <andrew@lunn.ch>
Signed-off-by: David S. Miller <davem@davemloft.net>