blob: eb74a8cf8df1c077670c3d84c37f7c872e37ff4b [file] [log] [blame]
// SPDX-License-Identifier: GPL-2.0+
/* Driver for Asix PHYs
*
* Author: Michael Schmitz <schmitzmic@gmail.com>
*/
#include <linux/kernel.h>
#include <linux/errno.h>
#include <linux/init.h>
#include <linux/module.h>
#include <linux/mii.h>
#include <linux/phy.h>
#define PHY_ID_ASIX_AX88772A 0x003b1861
#define PHY_ID_ASIX_AX88772C 0x003b1881
#define PHY_ID_ASIX_AX88796B 0x003b1841
MODULE_DESCRIPTION("Asix PHY driver");
MODULE_AUTHOR("Michael Schmitz <schmitzmic@gmail.com>");
MODULE_LICENSE("GPL");
/**
* asix_soft_reset - software reset the PHY via BMCR_RESET bit
* @phydev: target phy_device struct
*
* Description: Perform a software PHY reset using the standard
* BMCR_RESET bit and poll for the reset bit to be cleared.
* Toggle BMCR_RESET bit off to accommodate broken AX8796B PHY implementation
* such as used on the Individual Computers' X-Surf 100 Zorro card.
*
* Returns: 0 on success, < 0 on failure
*/
static int asix_soft_reset(struct phy_device *phydev)
{
int ret;
/* Asix PHY won't reset unless reset bit toggles */
ret = phy_write(phydev, MII_BMCR, 0);
if (ret < 0)
return ret;
return genphy_soft_reset(phydev);
}
/* AX88772A is not working properly with some old switches (NETGEAR EN 108TP):
* after autoneg is done and the link status is reported as active, the MII_LPA
* register is 0. This issue is not reproducible on AX88772C.
*/
static int asix_ax88772a_read_status(struct phy_device *phydev)
{
int ret, val;
ret = genphy_update_link(phydev);
if (ret)
return ret;
if (!phydev->link)
return 0;
/* If MII_LPA is 0, phy_resolve_aneg_linkmode() will fail to resolve
* linkmode so use MII_BMCR as default values.
*/
val = phy_read(phydev, MII_BMCR);
if (val < 0)
return val;
if (val & BMCR_SPEED100)
phydev->speed = SPEED_100;
else
phydev->speed = SPEED_10;
if (val & BMCR_FULLDPLX)
phydev->duplex = DUPLEX_FULL;
else
phydev->duplex = DUPLEX_HALF;
ret = genphy_read_lpa(phydev);
if (ret < 0)
return ret;
if (phydev->autoneg == AUTONEG_ENABLE && phydev->autoneg_complete)
phy_resolve_aneg_linkmode(phydev);
return 0;
}
static void asix_ax88772a_link_change_notify(struct phy_device *phydev)
{
/* Reset PHY, otherwise MII_LPA will provide outdated information.
* This issue is reproducible only with some link partner PHYs
*/
if (phydev->state == PHY_NOLINK) {
phy_init_hw(phydev);
_phy_start_aneg(phydev);
}
}
static struct phy_driver asix_driver[] = {
{
PHY_ID_MATCH_EXACT(PHY_ID_ASIX_AX88772A),
.name = "Asix Electronics AX88772A",
.flags = PHY_IS_INTERNAL,
.read_status = asix_ax88772a_read_status,
.suspend = genphy_suspend,
.resume = genphy_resume,
.soft_reset = asix_soft_reset,
.link_change_notify = asix_ax88772a_link_change_notify,
}, {
PHY_ID_MATCH_EXACT(PHY_ID_ASIX_AX88772C),
.name = "Asix Electronics AX88772C",
.flags = PHY_IS_INTERNAL,
.suspend = genphy_suspend,
.resume = genphy_resume,
.soft_reset = asix_soft_reset,
}, {
.phy_id = PHY_ID_ASIX_AX88796B,
.name = "Asix Electronics AX88796B",
.phy_id_mask = 0xfffffff0,
/* PHY_BASIC_FEATURES */
.soft_reset = asix_soft_reset,
} };
module_phy_driver(asix_driver);
static struct mdio_device_id __maybe_unused asix_tbl[] = {
{ PHY_ID_MATCH_EXACT(PHY_ID_ASIX_AX88772A) },
{ PHY_ID_MATCH_EXACT(PHY_ID_ASIX_AX88772C) },
{ PHY_ID_ASIX_AX88796B, 0xfffffff0 },
{ }
};
MODULE_DEVICE_TABLE(mdio, asix_tbl);