xref: /openbmc/linux/drivers/net/phy/qsemi.c (revision 2cf1c348)
1 // SPDX-License-Identifier: GPL-2.0+
2 /*
3  * drivers/net/phy/qsemi.c
4  *
5  * Driver for Quality Semiconductor PHYs
6  *
7  * Author: Andy Fleming
8  *
9  * Copyright (c) 2004 Freescale Semiconductor, Inc.
10  */
11 #include <linux/kernel.h>
12 #include <linux/string.h>
13 #include <linux/errno.h>
14 #include <linux/unistd.h>
15 #include <linux/interrupt.h>
16 #include <linux/init.h>
17 #include <linux/delay.h>
18 #include <linux/netdevice.h>
19 #include <linux/etherdevice.h>
20 #include <linux/skbuff.h>
21 #include <linux/spinlock.h>
22 #include <linux/mm.h>
23 #include <linux/module.h>
24 #include <linux/mii.h>
25 #include <linux/ethtool.h>
26 #include <linux/phy.h>
27 
28 #include <asm/io.h>
29 #include <asm/irq.h>
30 #include <linux/uaccess.h>
31 
32 /* ------------------------------------------------------------------------- */
33 /* The Quality Semiconductor QS6612 is used on the RPX CLLF                  */
34 
35 /* register definitions */
36 
37 #define MII_QS6612_MCR		17  /* Mode Control Register      */
38 #define MII_QS6612_FTR		27  /* Factory Test Register      */
39 #define MII_QS6612_MCO		28  /* Misc. Control Register     */
40 #define MII_QS6612_ISR		29  /* Interrupt Source Register  */
41 #define MII_QS6612_IMR		30  /* Interrupt Mask Register    */
42 #define MII_QS6612_IMR_INIT	0x003a
43 #define MII_QS6612_PCR		31  /* 100BaseTx PHY Control Reg. */
44 
45 #define QS6612_PCR_AN_COMPLETE	0x1000
46 #define QS6612_PCR_RLBEN	0x0200
47 #define QS6612_PCR_DCREN	0x0100
48 #define QS6612_PCR_4B5BEN	0x0040
49 #define QS6612_PCR_TX_ISOLATE	0x0020
50 #define QS6612_PCR_MLT3_DIS	0x0002
51 #define QS6612_PCR_SCRM_DESCRM	0x0001
52 
53 MODULE_DESCRIPTION("Quality Semiconductor PHY driver");
54 MODULE_AUTHOR("Andy Fleming");
55 MODULE_LICENSE("GPL");
56 
57 /* Returns 0, unless there's a write error */
58 static int qs6612_config_init(struct phy_device *phydev)
59 {
60 	/* The PHY powers up isolated on the RPX,
61 	 * so send a command to allow operation.
62 	 * XXX - My docs indicate this should be 0x0940
63 	 * ...or something.  The current value sets three
64 	 * reserved bits, bit 11, which specifies it should be
65 	 * set to one, bit 10, which specifies it should be set
66 	 * to 0, and bit 7, which doesn't specify.  However, my
67 	 * docs are preliminary, and I will leave it like this
68 	 * until someone more knowledgable corrects me or it.
69 	 * -- Andy Fleming
70 	 */
71 	return phy_write(phydev, MII_QS6612_PCR, 0x0dc0);
72 }
73 
74 static int qs6612_ack_interrupt(struct phy_device *phydev)
75 {
76 	int err;
77 
78 	/* The Interrupt Source register is not self-clearing, bits 4 and 5 are
79 	 * cleared when MII_BMSR is read and bits 1 and 3 are cleared when
80 	 * MII_EXPANSION is read
81 	 */
82 	err = phy_read(phydev, MII_QS6612_ISR);
83 
84 	if (err < 0)
85 		return err;
86 
87 	err = phy_read(phydev, MII_BMSR);
88 
89 	if (err < 0)
90 		return err;
91 
92 	err = phy_read(phydev, MII_EXPANSION);
93 
94 	if (err < 0)
95 		return err;
96 
97 	return 0;
98 }
99 
100 static int qs6612_config_intr(struct phy_device *phydev)
101 {
102 	int err;
103 
104 	if (phydev->interrupts == PHY_INTERRUPT_ENABLED) {
105 		/* clear any interrupts before enabling them */
106 		err = qs6612_ack_interrupt(phydev);
107 		if (err)
108 			return err;
109 
110 		err = phy_write(phydev, MII_QS6612_IMR,
111 				MII_QS6612_IMR_INIT);
112 	} else {
113 		err = phy_write(phydev, MII_QS6612_IMR, 0);
114 		if (err)
115 			return err;
116 
117 		/* clear any leftover interrupts */
118 		err = qs6612_ack_interrupt(phydev);
119 	}
120 
121 	return err;
122 
123 }
124 
125 static irqreturn_t qs6612_handle_interrupt(struct phy_device *phydev)
126 {
127 	int irq_status;
128 
129 	irq_status = phy_read(phydev, MII_QS6612_ISR);
130 	if (irq_status < 0) {
131 		phy_error(phydev);
132 		return IRQ_NONE;
133 	}
134 
135 	if (!(irq_status & MII_QS6612_IMR_INIT))
136 		return IRQ_NONE;
137 
138 	/* the interrupt source register is not self-clearing */
139 	qs6612_ack_interrupt(phydev);
140 
141 	phy_trigger_machine(phydev);
142 
143 	return IRQ_HANDLED;
144 }
145 
146 static struct phy_driver qs6612_driver[] = { {
147 	.phy_id		= 0x00181440,
148 	.name		= "QS6612",
149 	.phy_id_mask	= 0xfffffff0,
150 	/* PHY_BASIC_FEATURES */
151 	.config_init	= qs6612_config_init,
152 	.config_intr	= qs6612_config_intr,
153 	.handle_interrupt = qs6612_handle_interrupt,
154 } };
155 
156 module_phy_driver(qs6612_driver);
157 
158 static struct mdio_device_id __maybe_unused qs6612_tbl[] = {
159 	{ 0x00181440, 0xfffffff0 },
160 	{ }
161 };
162 
163 MODULE_DEVICE_TABLE(mdio, qs6612_tbl);
164