1 // SPDX-License-Identifier: GPL-2.0+
2 /*
3 * Driver for AMD am79c PHYs
4 *
5 * Author: Heiko Schocher <hs@denx.de>
6 *
7 * Copyright (c) 2011 DENX Software Engineering GmbH
8 */
9 #include <linux/kernel.h>
10 #include <linux/errno.h>
11 #include <linux/init.h>
12 #include <linux/module.h>
13 #include <linux/mii.h>
14 #include <linux/phy.h>
15
16 #define PHY_ID_AM79C874 0x0022561b
17
18 #define MII_AM79C_IR 17 /* Interrupt Status/Control Register */
19 #define MII_AM79C_IR_EN_LINK 0x0400 /* IR enable Linkstate */
20 #define MII_AM79C_IR_EN_ANEG 0x0100 /* IR enable Aneg Complete */
21 #define MII_AM79C_IR_IMASK_INIT (MII_AM79C_IR_EN_LINK | MII_AM79C_IR_EN_ANEG)
22
23 #define MII_AM79C_IR_LINK_DOWN BIT(2)
24 #define MII_AM79C_IR_ANEG_DONE BIT(0)
25 #define MII_AM79C_IR_IMASK_STAT (MII_AM79C_IR_LINK_DOWN | MII_AM79C_IR_ANEG_DONE)
26
27 MODULE_DESCRIPTION("AMD PHY driver");
28 MODULE_AUTHOR("Heiko Schocher <hs@denx.de>");
29 MODULE_LICENSE("GPL");
30
am79c_ack_interrupt(struct phy_device * phydev)31 static int am79c_ack_interrupt(struct phy_device *phydev)
32 {
33 int err;
34
35 err = phy_read(phydev, MII_BMSR);
36 if (err < 0)
37 return err;
38
39 err = phy_read(phydev, MII_AM79C_IR);
40 if (err < 0)
41 return err;
42
43 return 0;
44 }
45
am79c_config_init(struct phy_device * phydev)46 static int am79c_config_init(struct phy_device *phydev)
47 {
48 return 0;
49 }
50
am79c_config_intr(struct phy_device * phydev)51 static int am79c_config_intr(struct phy_device *phydev)
52 {
53 int err;
54
55 if (phydev->interrupts == PHY_INTERRUPT_ENABLED) {
56 err = am79c_ack_interrupt(phydev);
57 if (err)
58 return err;
59
60 err = phy_write(phydev, MII_AM79C_IR, MII_AM79C_IR_IMASK_INIT);
61 } else {
62 err = phy_write(phydev, MII_AM79C_IR, 0);
63 if (err)
64 return err;
65
66 err = am79c_ack_interrupt(phydev);
67 }
68
69 return err;
70 }
71
am79c_handle_interrupt(struct phy_device * phydev)72 static irqreturn_t am79c_handle_interrupt(struct phy_device *phydev)
73 {
74 int irq_status;
75
76 irq_status = phy_read(phydev, MII_AM79C_IR);
77 if (irq_status < 0) {
78 phy_error(phydev);
79 return IRQ_NONE;
80 }
81
82 if (!(irq_status & MII_AM79C_IR_IMASK_STAT))
83 return IRQ_NONE;
84
85 phy_trigger_machine(phydev);
86
87 return IRQ_HANDLED;
88 }
89
90 static struct phy_driver am79c_driver[] = { {
91 .phy_id = PHY_ID_AM79C874,
92 .name = "AM79C874",
93 .phy_id_mask = 0xfffffff0,
94 /* PHY_BASIC_FEATURES */
95 .config_init = am79c_config_init,
96 .config_intr = am79c_config_intr,
97 .handle_interrupt = am79c_handle_interrupt,
98 } };
99
100 module_phy_driver(am79c_driver);
101
102 static struct mdio_device_id __maybe_unused amd_tbl[] = {
103 { PHY_ID_AM79C874, 0xfffffff0 },
104 { }
105 };
106
107 MODULE_DEVICE_TABLE(mdio, amd_tbl);
108