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 /* DP83865 phy identifier values */
23 #define DP83865_PHY_ID 0x20005c7a
24
25 #define DP83865_INT_STATUS 0x14
26 #define DP83865_INT_MASK 0x15
27 #define DP83865_INT_CLEAR 0x17
28
29 #define DP83865_INT_REMOTE_FAULT 0x0008
30 #define DP83865_INT_ANE_COMPLETED 0x0010
31 #define DP83865_INT_LINK_CHANGE 0xe000
32 #define DP83865_INT_MASK_DEFAULT (DP83865_INT_REMOTE_FAULT | \
33 DP83865_INT_ANE_COMPLETED | \
34 DP83865_INT_LINK_CHANGE)
35
36 /* Advanced proprietary configuration */
37 #define NS_EXP_MEM_CTL 0x16
38 #define NS_EXP_MEM_DATA 0x1d
39 #define NS_EXP_MEM_ADD 0x1e
40
41 #define LED_CTRL_REG 0x13
42 #define AN_FALLBACK_AN 0x0001
43 #define AN_FALLBACK_CRC 0x0002
44 #define AN_FALLBACK_IE 0x0004
45 #define ALL_FALLBACK_ON (AN_FALLBACK_AN | AN_FALLBACK_CRC | AN_FALLBACK_IE)
46
47 enum hdx_loopback {
48 hdx_loopback_on = 0,
49 hdx_loopback_off = 1,
50 };
51
ns_exp_read(struct phy_device * phydev,u16 reg)52 static u8 ns_exp_read(struct phy_device *phydev, u16 reg)
53 {
54 phy_write(phydev, NS_EXP_MEM_ADD, reg);
55 return phy_read(phydev, NS_EXP_MEM_DATA);
56 }
57
ns_exp_write(struct phy_device * phydev,u16 reg,u8 data)58 static void ns_exp_write(struct phy_device *phydev, u16 reg, u8 data)
59 {
60 phy_write(phydev, NS_EXP_MEM_ADD, reg);
61 phy_write(phydev, NS_EXP_MEM_DATA, data);
62 }
63
ns_ack_interrupt(struct phy_device * phydev)64 static int ns_ack_interrupt(struct phy_device *phydev)
65 {
66 int ret = phy_read(phydev, DP83865_INT_STATUS);
67 if (ret < 0)
68 return ret;
69
70 /* Clear the interrupt status bit by writing a “1”
71 * to the corresponding bit in INT_CLEAR (2:0 are reserved)
72 */
73 ret = phy_write(phydev, DP83865_INT_CLEAR, ret & ~0x7);
74
75 return ret;
76 }
77
ns_handle_interrupt(struct phy_device * phydev)78 static irqreturn_t ns_handle_interrupt(struct phy_device *phydev)
79 {
80 int irq_status;
81
82 irq_status = phy_read(phydev, DP83865_INT_STATUS);
83 if (irq_status < 0) {
84 phy_error(phydev);
85 return IRQ_NONE;
86 }
87
88 if (!(irq_status & DP83865_INT_MASK_DEFAULT))
89 return IRQ_NONE;
90
91 /* clear the interrupt */
92 phy_write(phydev, DP83865_INT_CLEAR, irq_status & ~0x7);
93
94 phy_trigger_machine(phydev);
95
96 return IRQ_HANDLED;
97 }
98
ns_config_intr(struct phy_device * phydev)99 static int ns_config_intr(struct phy_device *phydev)
100 {
101 int err;
102
103 if (phydev->interrupts == PHY_INTERRUPT_ENABLED) {
104 err = ns_ack_interrupt(phydev);
105 if (err)
106 return err;
107
108 err = phy_write(phydev, DP83865_INT_MASK,
109 DP83865_INT_MASK_DEFAULT);
110 } else {
111 err = phy_write(phydev, DP83865_INT_MASK, 0);
112 if (err)
113 return err;
114
115 err = ns_ack_interrupt(phydev);
116 }
117
118 return err;
119 }
120
ns_giga_speed_fallback(struct phy_device * phydev,int mode)121 static void ns_giga_speed_fallback(struct phy_device *phydev, int mode)
122 {
123 int bmcr = phy_read(phydev, MII_BMCR);
124
125 phy_write(phydev, MII_BMCR, (bmcr | BMCR_PDOWN));
126
127 /* Enable 8 bit expended memory read/write (no auto increment) */
128 phy_write(phydev, NS_EXP_MEM_CTL, 0);
129 phy_write(phydev, NS_EXP_MEM_ADD, 0x1C0);
130 phy_write(phydev, NS_EXP_MEM_DATA, 0x0008);
131 phy_write(phydev, MII_BMCR, (bmcr & ~BMCR_PDOWN));
132 phy_write(phydev, LED_CTRL_REG, mode);
133 }
134
ns_10_base_t_hdx_loopack(struct phy_device * phydev,int disable)135 static void ns_10_base_t_hdx_loopack(struct phy_device *phydev, int disable)
136 {
137 u16 lb_dis = BIT(1);
138
139 if (disable)
140 ns_exp_write(phydev, 0x1c0,
141 ns_exp_read(phydev, 0x1c0) | lb_dis);
142 else
143 ns_exp_write(phydev, 0x1c0,
144 ns_exp_read(phydev, 0x1c0) & ~lb_dis);
145
146 pr_debug("10BASE-T HDX loopback %s\n",
147 (ns_exp_read(phydev, 0x1c0) & lb_dis) ? "off" : "on");
148 }
149
ns_config_init(struct phy_device * phydev)150 static int ns_config_init(struct phy_device *phydev)
151 {
152 ns_giga_speed_fallback(phydev, ALL_FALLBACK_ON);
153 /* In the latest MAC or switches design, the 10 Mbps loopback
154 * is desired to be turned off.
155 */
156 ns_10_base_t_hdx_loopack(phydev, hdx_loopback_off);
157 return ns_ack_interrupt(phydev);
158 }
159
160 static struct phy_driver dp83865_driver[] = { {
161 .phy_id = DP83865_PHY_ID,
162 .phy_id_mask = 0xfffffff0,
163 .name = "NatSemi DP83865",
164 /* PHY_GBIT_FEATURES */
165 .config_init = ns_config_init,
166 .config_intr = ns_config_intr,
167 .handle_interrupt = ns_handle_interrupt,
168 } };
169
170 module_phy_driver(dp83865_driver);
171
172 MODULE_DESCRIPTION("NatSemi PHY driver");
173 MODULE_AUTHOR("Stuart Menefy");
174 MODULE_LICENSE("GPL");
175
176 static struct mdio_device_id __maybe_unused ns_tbl[] = {
177 { DP83865_PHY_ID, 0xfffffff0 },
178 { }
179 };
180
181 MODULE_DEVICE_TABLE(mdio, ns_tbl);
182