LXR linux/drivers/net/phy/national.c

   1// SPDX-License-Identifier: GPL-2.0+
   2/*
   3 * drivers/net/phy/national.c
   4 *
   5 * Driver for National Semiconductor PHYs
   6 *
   7 * Author: Stuart Menefy <stuart.menefy@st.com>
   8 * Maintainer: Giuseppe Cavallaro <peppe.cavallaro@st.com>
   9 *
  10 * Copyright (c) 2008 STMicroelectronics Limited
  11 */
  12
  13#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
  14
  15#include <linux/kernel.h>
  16#include <linux/module.h>
  17#include <linux/mii.h>
  18#include <linux/ethtool.h>
  19#include <linux/phy.h>
  20#include <linux/netdevice.h>
  21
  22#define DEBUG
  23
  24/* DP83865 phy identifier values */
  25#define DP83865_PHY_ID  0x20005c7a
  26
  27#define DP83865_INT_STATUS      0x14
  28#define DP83865_INT_MASK        0x15
  29#define DP83865_INT_CLEAR       0x17
  30
  31#define DP83865_INT_REMOTE_FAULT 0x0008
  32#define DP83865_INT_ANE_COMPLETED 0x0010
  33#define DP83865_INT_LINK_CHANGE 0xe000
  34#define DP83865_INT_MASK_DEFAULT (DP83865_INT_REMOTE_FAULT | \
  35                                DP83865_INT_ANE_COMPLETED | \
  36                                DP83865_INT_LINK_CHANGE)
  37
  38/* Advanced proprietary configuration */
  39#define NS_EXP_MEM_CTL  0x16
  40#define NS_EXP_MEM_DATA 0x1d
  41#define NS_EXP_MEM_ADD  0x1e
  42
  43#define LED_CTRL_REG 0x13
  44#define AN_FALLBACK_AN 0x0001
  45#define AN_FALLBACK_CRC 0x0002
  46#define AN_FALLBACK_IE 0x0004
  47#define ALL_FALLBACK_ON (AN_FALLBACK_AN |  AN_FALLBACK_CRC | AN_FALLBACK_IE)
  48
  49enum hdx_loopback {
  50        hdx_loopback_on = 0,
  51        hdx_loopback_off = 1,
  52};
  53
  54static u8 ns_exp_read(struct phy_device *phydev, u16 reg)
  55{
  56        phy_write(phydev, NS_EXP_MEM_ADD, reg);
  57        return phy_read(phydev, NS_EXP_MEM_DATA);
  58}
  59
  60static void ns_exp_write(struct phy_device *phydev, u16 reg, u8 data)
  61{
  62        phy_write(phydev, NS_EXP_MEM_ADD, reg);
  63        phy_write(phydev, NS_EXP_MEM_DATA, data);
  64}
  65
  66static int ns_config_intr(struct phy_device *phydev)
  67{
  68        int err;
  69
  70        if (phydev->interrupts == PHY_INTERRUPT_ENABLED)
  71                err = phy_write(phydev, DP83865_INT_MASK,
  72                                DP83865_INT_MASK_DEFAULT);
  73        else
  74                err = phy_write(phydev, DP83865_INT_MASK, 0);
  75
  76        return err;
  77}
  78
  79static int ns_ack_interrupt(struct phy_device *phydev)
  80{
  81        int ret = phy_read(phydev, DP83865_INT_STATUS);
  82        if (ret < 0)
  83                return ret;
  84
  85        /* Clear the interrupt status bit by writing a “1”
  86         * to the corresponding bit in INT_CLEAR (2:0 are reserved) */
  87        ret = phy_write(phydev, DP83865_INT_CLEAR, ret & ~0x7);
  88
  89        return ret;
  90}
  91
  92static void ns_giga_speed_fallback(struct phy_device *phydev, int mode)
  93{
  94        int bmcr = phy_read(phydev, MII_BMCR);
  95
  96        phy_write(phydev, MII_BMCR, (bmcr | BMCR_PDOWN));
  97
  98        /* Enable 8 bit expended memory read/write (no auto increment) */
  99        phy_write(phydev, NS_EXP_MEM_CTL, 0);
 100        phy_write(phydev, NS_EXP_MEM_ADD, 0x1C0);
 101        phy_write(phydev, NS_EXP_MEM_DATA, 0x0008);
 102        phy_write(phydev, MII_BMCR, (bmcr & ~BMCR_PDOWN));
 103        phy_write(phydev, LED_CTRL_REG, mode);
 104}
 105
 106static void ns_10_base_t_hdx_loopack(struct phy_device *phydev, int disable)
 107{
 108        if (disable)
 109                ns_exp_write(phydev, 0x1c0, ns_exp_read(phydev, 0x1c0) | 1);
 110        else
 111                ns_exp_write(phydev, 0x1c0,
 112                             ns_exp_read(phydev, 0x1c0) & 0xfffe);
 113
 114        pr_debug("10BASE-T HDX loopback %s\n",
 115                 (ns_exp_read(phydev, 0x1c0) & 0x0001) ? "off" : "on");
 116}
 117
 118static int ns_config_init(struct phy_device *phydev)
 119{
 120        ns_giga_speed_fallback(phydev, ALL_FALLBACK_ON);
 121        /* In the latest MAC or switches design, the 10 Mbps loopback
 122           is desired to be turned off. */
 123        ns_10_base_t_hdx_loopack(phydev, hdx_loopback_off);
 124        return ns_ack_interrupt(phydev);
 125}
 126
 127static struct phy_driver dp83865_driver[] = { {
 128        .phy_id = DP83865_PHY_ID,
 129        .phy_id_mask = 0xfffffff0,
 130        .name = "NatSemi DP83865",
 131        /* PHY_GBIT_FEATURES */
 132        .config_init = ns_config_init,
 133        .ack_interrupt = ns_ack_interrupt,
 134        .config_intr = ns_config_intr,
 135} };
 136
 137module_phy_driver(dp83865_driver);
 138
 139MODULE_DESCRIPTION("NatSemi PHY driver");
 140MODULE_AUTHOR("Stuart Menefy");
 141MODULE_LICENSE("GPL");
 142
 143static struct mdio_device_id __maybe_unused ns_tbl[] = {
 144        { DP83865_PHY_ID, 0xfffffff0 },
 145        { }
 146};
 147
 148MODULE_DEVICE_TABLE(mdio, ns_tbl);
 149