net/phy/amd.c

0001 // SPDX-License-Identifier: GPL-2.0+
0002 /*
0003  * Driver for AMD am79c PHYs
0004  *
0005  * Author: Heiko Schocher <hs@denx.de>
0006  *
0007  * Copyright (c) 2011 DENX Software Engineering GmbH
0008  */
0009 #include <linux/kernel.h>
0010 #include <linux/errno.h>
0011 #include <linux/init.h>
0012 #include <linux/module.h>
0013 #include <linux/mii.h>
0014 #include <linux/phy.h>
0015
0016 #define PHY_ID_AM79C874     0x0022561b
0017
0018 #define MII_AM79C_IR        17  /* Interrupt Status/Control Register */
0019 #define MII_AM79C_IR_EN_LINK    0x0400  /* IR enable Linkstate */
0020 #define MII_AM79C_IR_EN_ANEG    0x0100  /* IR enable Aneg Complete */
0021 #define MII_AM79C_IR_IMASK_INIT (MII_AM79C_IR_EN_LINK | MII_AM79C_IR_EN_ANEG)
0022
0023 #define MII_AM79C_IR_LINK_DOWN  BIT(2)
0024 #define MII_AM79C_IR_ANEG_DONE  BIT(0)
0025 #define MII_AM79C_IR_IMASK_STAT (MII_AM79C_IR_LINK_DOWN | MII_AM79C_IR_ANEG_DONE)
0026
0027 MODULE_DESCRIPTION("AMD PHY driver");
0028 MODULE_AUTHOR("Heiko Schocher <hs@denx.de>");
0029 MODULE_LICENSE("GPL");
0030
0031 static int am79c_ack_interrupt(struct phy_device *phydev)
0032 {
0033     int err;
0034
0035     err = phy_read(phydev, MII_BMSR);
0036     if (err < 0)
0037         return err;
0038
0039     err = phy_read(phydev, MII_AM79C_IR);
0040     if (err < 0)
0041         return err;
0042
0043     return 0;
0044 }
0045
0046 static int am79c_config_init(struct phy_device *phydev)
0047 {
0048     return 0;
0049 }
0050
0051 static int am79c_config_intr(struct phy_device *phydev)
0052 {
0053     int err;
0054
0055     if (phydev->interrupts == PHY_INTERRUPT_ENABLED) {
0056         err = am79c_ack_interrupt(phydev);
0057         if (err)
0058             return err;
0059
0060         err = phy_write(phydev, MII_AM79C_IR, MII_AM79C_IR_IMASK_INIT);
0061     } else {
0062         err = phy_write(phydev, MII_AM79C_IR, 0);
0063         if (err)
0064             return err;
0065
0066         err = am79c_ack_interrupt(phydev);
0067     }
0068
0069     return err;
0070 }
0071
0072 static irqreturn_t am79c_handle_interrupt(struct phy_device *phydev)
0073 {
0074     int irq_status;
0075
0076     irq_status = phy_read(phydev, MII_AM79C_IR);
0077     if (irq_status < 0) {
0078         phy_error(phydev);
0079         return IRQ_NONE;
0080     }
0081
0082     if (!(irq_status & MII_AM79C_IR_IMASK_STAT))
0083         return IRQ_NONE;
0084
0085     phy_trigger_machine(phydev);
0086
0087     return IRQ_HANDLED;
0088 }
0089
0090 static struct phy_driver am79c_driver[] = { {
0091     .phy_id     = PHY_ID_AM79C874,
0092     .name       = "AM79C874",
0093     .phy_id_mask    = 0xfffffff0,
0094     /* PHY_BASIC_FEATURES */
0095     .config_init    = am79c_config_init,
0096     .config_intr    = am79c_config_intr,
0097     .handle_interrupt = am79c_handle_interrupt,
0098 } };
0099
0100 module_phy_driver(am79c_driver);
0101
0102 static struct mdio_device_id __maybe_unused amd_tbl[] = {
0103     { PHY_ID_AM79C874, 0xfffffff0 },
0104     { }
0105 };
0106
0107 MODULE_DEVICE_TABLE(mdio, amd_tbl);