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