1*4882a593Smuzhiyun // SPDX-License-Identifier: GPL-2.0+
2*4882a593Smuzhiyun /* Driver for Asix PHYs
3*4882a593Smuzhiyun *
4*4882a593Smuzhiyun * Author: Michael Schmitz <schmitzmic@gmail.com>
5*4882a593Smuzhiyun */
6*4882a593Smuzhiyun #include <linux/kernel.h>
7*4882a593Smuzhiyun #include <linux/errno.h>
8*4882a593Smuzhiyun #include <linux/init.h>
9*4882a593Smuzhiyun #include <linux/module.h>
10*4882a593Smuzhiyun #include <linux/mii.h>
11*4882a593Smuzhiyun #include <linux/phy.h>
12*4882a593Smuzhiyun
13*4882a593Smuzhiyun #define PHY_ID_ASIX_AX88796B 0x003b1841
14*4882a593Smuzhiyun
15*4882a593Smuzhiyun MODULE_DESCRIPTION("Asix PHY driver");
16*4882a593Smuzhiyun MODULE_AUTHOR("Michael Schmitz <schmitzmic@gmail.com>");
17*4882a593Smuzhiyun MODULE_LICENSE("GPL");
18*4882a593Smuzhiyun
19*4882a593Smuzhiyun /**
20*4882a593Smuzhiyun * asix_soft_reset - software reset the PHY via BMCR_RESET bit
21*4882a593Smuzhiyun * @phydev: target phy_device struct
22*4882a593Smuzhiyun *
23*4882a593Smuzhiyun * Description: Perform a software PHY reset using the standard
24*4882a593Smuzhiyun * BMCR_RESET bit and poll for the reset bit to be cleared.
25*4882a593Smuzhiyun * Toggle BMCR_RESET bit off to accommodate broken AX8796B PHY implementation
26*4882a593Smuzhiyun * such as used on the Individual Computers' X-Surf 100 Zorro card.
27*4882a593Smuzhiyun *
28*4882a593Smuzhiyun * Returns: 0 on success, < 0 on failure
29*4882a593Smuzhiyun */
asix_soft_reset(struct phy_device * phydev)30*4882a593Smuzhiyun static int asix_soft_reset(struct phy_device *phydev)
31*4882a593Smuzhiyun {
32*4882a593Smuzhiyun int ret;
33*4882a593Smuzhiyun
34*4882a593Smuzhiyun /* Asix PHY won't reset unless reset bit toggles */
35*4882a593Smuzhiyun ret = phy_write(phydev, MII_BMCR, 0);
36*4882a593Smuzhiyun if (ret < 0)
37*4882a593Smuzhiyun return ret;
38*4882a593Smuzhiyun
39*4882a593Smuzhiyun return genphy_soft_reset(phydev);
40*4882a593Smuzhiyun }
41*4882a593Smuzhiyun
42*4882a593Smuzhiyun static struct phy_driver asix_driver[] = { {
43*4882a593Smuzhiyun .phy_id = PHY_ID_ASIX_AX88796B,
44*4882a593Smuzhiyun .name = "Asix Electronics AX88796B",
45*4882a593Smuzhiyun .phy_id_mask = 0xfffffff0,
46*4882a593Smuzhiyun /* PHY_BASIC_FEATURES */
47*4882a593Smuzhiyun .soft_reset = asix_soft_reset,
48*4882a593Smuzhiyun } };
49*4882a593Smuzhiyun
50*4882a593Smuzhiyun module_phy_driver(asix_driver);
51*4882a593Smuzhiyun
52*4882a593Smuzhiyun static struct mdio_device_id __maybe_unused asix_tbl[] = {
53*4882a593Smuzhiyun { PHY_ID_ASIX_AX88796B, 0xfffffff0 },
54*4882a593Smuzhiyun { }
55*4882a593Smuzhiyun };
56*4882a593Smuzhiyun
57*4882a593Smuzhiyun MODULE_DEVICE_TABLE(mdio, asix_tbl);
58