xref: /linux/drivers/net/phy/amd.c (revision 4f77c3462308c62ffe7129cc18b9ac937f44b5a5)
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_AC101L		0x00225520
17 #define PHY_ID_AM79C874		0x0022561b
18 
19 #define MII_AM79C_IR		17	/* Interrupt Status/Control Register */
20 #define MII_AM79C_IR_EN_LINK	0x0400	/* IR enable Linkstate */
21 #define MII_AM79C_IR_EN_ANEG	0x0100	/* IR enable Aneg Complete */
22 #define MII_AM79C_IR_IMASK_INIT	(MII_AM79C_IR_EN_LINK | MII_AM79C_IR_EN_ANEG)
23 
24 #define MII_AM79C_IR_LINK_DOWN	BIT(2)
25 #define MII_AM79C_IR_ANEG_DONE	BIT(0)
26 #define MII_AM79C_IR_IMASK_STAT	(MII_AM79C_IR_LINK_DOWN | MII_AM79C_IR_ANEG_DONE)
27 
28 MODULE_DESCRIPTION("AMD PHY driver");
29 MODULE_AUTHOR("Heiko Schocher <hs@denx.de>");
30 MODULE_LICENSE("GPL");
31 
32 static int am79c_ack_interrupt(struct phy_device *phydev)
33 {
34 	int err;
35 
36 	err = phy_read(phydev, MII_BMSR);
37 	if (err < 0)
38 		return err;
39 
40 	err = phy_read(phydev, MII_AM79C_IR);
41 	if (err < 0)
42 		return err;
43 
44 	return 0;
45 }
46 
47 static int am79c_config_init(struct phy_device *phydev)
48 {
49 	return 0;
50 }
51 
52 static int am79c_config_intr(struct phy_device *phydev)
53 {
54 	int err;
55 
56 	if (phydev->interrupts == PHY_INTERRUPT_ENABLED) {
57 		err = am79c_ack_interrupt(phydev);
58 		if (err)
59 			return err;
60 
61 		err = phy_write(phydev, MII_AM79C_IR, MII_AM79C_IR_IMASK_INIT);
62 	} else {
63 		err = phy_write(phydev, MII_AM79C_IR, 0);
64 		if (err)
65 			return err;
66 
67 		err = am79c_ack_interrupt(phydev);
68 	}
69 
70 	return err;
71 }
72 
73 static irqreturn_t am79c_handle_interrupt(struct phy_device *phydev)
74 {
75 	int irq_status;
76 
77 	irq_status = phy_read(phydev, MII_AM79C_IR);
78 	if (irq_status < 0) {
79 		phy_error(phydev);
80 		return IRQ_NONE;
81 	}
82 
83 	if (!(irq_status & MII_AM79C_IR_IMASK_STAT))
84 		return IRQ_NONE;
85 
86 	phy_trigger_machine(phydev);
87 
88 	return IRQ_HANDLED;
89 }
90 
91 static struct phy_driver am79c_drivers[] = {
92 	{
93 		.phy_id		= PHY_ID_AM79C874,
94 		.name		= "AM79C874",
95 		.phy_id_mask	= 0xfffffff0,
96 		/* PHY_BASIC_FEATURES */
97 		.config_init	= am79c_config_init,
98 		.config_intr	= am79c_config_intr,
99 		.handle_interrupt = am79c_handle_interrupt,
100 	},
101 	{
102 		.phy_id		= PHY_ID_AC101L,
103 		.name		= "AC101L",
104 		.phy_id_mask	= 0xfffffff0,
105 		/* PHY_BASIC_FEATURES */
106 		.config_init	= am79c_config_init,
107 		.config_intr	= am79c_config_intr,
108 		.handle_interrupt = am79c_handle_interrupt,
109 	},
110 };
111 
112 module_phy_driver(am79c_drivers);
113 
114 static struct mdio_device_id __maybe_unused amd_tbl[] = {
115 	{ PHY_ID_AC101L, 0xfffffff0 },
116 	{ PHY_ID_AM79C874, 0xfffffff0 },
117 	{ }
118 };
119 
120 MODULE_DEVICE_TABLE(mdio, amd_tbl);
121