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
49 enum hdx_loopback {
50 hdx_loopback_on = 0,
51 hdx_loopback_off = 1,
52 };
53
ns_exp_read(struct phy_device * phydev,u16 reg)54 static 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
ns_exp_write(struct phy_device * phydev,u16 reg,u8 data)60 static 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
ns_config_intr(struct phy_device * phydev)66 static 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
ns_ack_interrupt(struct phy_device * phydev)79 static 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
ns_giga_speed_fallback(struct phy_device * phydev,int mode)92 static 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
ns_10_base_t_hdx_loopack(struct phy_device * phydev,int disable)106 static void ns_10_base_t_hdx_loopack(struct phy_device *phydev, int disable)
107 {
108 u16 lb_dis = BIT(1);
109
110 if (disable)
111 ns_exp_write(phydev, 0x1c0,
112 ns_exp_read(phydev, 0x1c0) | lb_dis);
113 else
114 ns_exp_write(phydev, 0x1c0,
115 ns_exp_read(phydev, 0x1c0) & ~lb_dis);
116
117 pr_debug("10BASE-T HDX loopback %s\n",
118 (ns_exp_read(phydev, 0x1c0) & lb_dis) ? "off" : "on");
119 }
120
ns_config_init(struct phy_device * phydev)121 static int ns_config_init(struct phy_device *phydev)
122 {
123 ns_giga_speed_fallback(phydev, ALL_FALLBACK_ON);
124 /* In the latest MAC or switches design, the 10 Mbps loopback
125 is desired to be turned off. */
126 ns_10_base_t_hdx_loopack(phydev, hdx_loopback_off);
127 return ns_ack_interrupt(phydev);
128 }
129
130 static struct phy_driver dp83865_driver[] = { {
131 .phy_id = DP83865_PHY_ID,
132 .phy_id_mask = 0xfffffff0,
133 .name = "NatSemi DP83865",
134 /* PHY_GBIT_FEATURES */
135 .config_init = ns_config_init,
136 .ack_interrupt = ns_ack_interrupt,
137 .config_intr = ns_config_intr,
138 } };
139
140 module_phy_driver(dp83865_driver);
141
142 MODULE_DESCRIPTION("NatSemi PHY driver");
143 MODULE_AUTHOR("Stuart Menefy");
144 MODULE_LICENSE("GPL");
145
146 static struct mdio_device_id __maybe_unused ns_tbl[] = {
147 { DP83865_PHY_ID, 0xfffffff0 },
148 { }
149 };
150
151 MODULE_DEVICE_TABLE(mdio, ns_tbl);
152