1 // SPDX-License-Identifier: GPL-2.0
2 /*
3 * This files contains card eeprom (93c46 or 93c56) programming routines,
4 * memory is addressed by 16 bits words.
5 *
6 * This is part of rtl8180 OpenSource driver.
7 * Copyright (C) Andrea Merello 2004 <andrea.merello@gmail.com>
8 *
9 * Parts of this driver are based on the GPL part of the
10 * official realtek driver.
11 *
12 * Parts of this driver are based on the rtl8180 driver skeleton
13 * from Patric Schenke & Andres Salomon.
14 *
15 * Parts of this driver are based on the Intel Pro Wireless 2100 GPL driver.
16 *
17 * We want to thank the Authors of those projects and the Ndiswrapper
18 * project Authors.
19 */
20
21 #include "r8180_93cx6.h"
22
eprom_cs(struct net_device * dev,short bit)23 static void eprom_cs(struct net_device *dev, short bit)
24 {
25 u8 cmdreg;
26 int err;
27
28 err = read_nic_byte_E(dev, EPROM_CMD, &cmdreg);
29 if (err)
30 return;
31 if (bit)
32 /* enable EPROM */
33 write_nic_byte_E(dev, EPROM_CMD, cmdreg | EPROM_CS_BIT);
34 else
35 /* disable EPROM */
36 write_nic_byte_E(dev, EPROM_CMD, cmdreg & ~EPROM_CS_BIT);
37
38 force_pci_posting(dev);
39 udelay(EPROM_DELAY);
40 }
41
eprom_ck_cycle(struct net_device * dev)42 static void eprom_ck_cycle(struct net_device *dev)
43 {
44 u8 cmdreg;
45 int err;
46
47 err = read_nic_byte_E(dev, EPROM_CMD, &cmdreg);
48 if (err)
49 return;
50 write_nic_byte_E(dev, EPROM_CMD, cmdreg | EPROM_CK_BIT);
51 force_pci_posting(dev);
52 udelay(EPROM_DELAY);
53
54 read_nic_byte_E(dev, EPROM_CMD, &cmdreg);
55 write_nic_byte_E(dev, EPROM_CMD, cmdreg & ~EPROM_CK_BIT);
56 force_pci_posting(dev);
57 udelay(EPROM_DELAY);
58 }
59
eprom_w(struct net_device * dev,short bit)60 static void eprom_w(struct net_device *dev, short bit)
61 {
62 u8 cmdreg;
63 int err;
64
65 err = read_nic_byte_E(dev, EPROM_CMD, &cmdreg);
66 if (err)
67 return;
68 if (bit)
69 write_nic_byte_E(dev, EPROM_CMD, cmdreg | EPROM_W_BIT);
70 else
71 write_nic_byte_E(dev, EPROM_CMD, cmdreg & ~EPROM_W_BIT);
72
73 force_pci_posting(dev);
74 udelay(EPROM_DELAY);
75 }
76
eprom_r(struct net_device * dev)77 static short eprom_r(struct net_device *dev)
78 {
79 u8 bit;
80 int err;
81
82 err = read_nic_byte_E(dev, EPROM_CMD, &bit);
83 if (err)
84 return err;
85
86 udelay(EPROM_DELAY);
87
88 if (bit & EPROM_R_BIT)
89 return 1;
90
91 return 0;
92 }
93
eprom_send_bits_string(struct net_device * dev,short b[],int len)94 static void eprom_send_bits_string(struct net_device *dev, short b[], int len)
95 {
96 int i;
97
98 for (i = 0; i < len; i++) {
99 eprom_w(dev, b[i]);
100 eprom_ck_cycle(dev);
101 }
102 }
103
eprom_read(struct net_device * dev,u32 addr)104 int eprom_read(struct net_device *dev, u32 addr)
105 {
106 struct r8192_priv *priv = ieee80211_priv(dev);
107 short read_cmd[] = {1, 1, 0};
108 short addr_str[8];
109 int i;
110 int addr_len;
111 u32 ret;
112 int err;
113
114 ret = 0;
115 /* enable EPROM programming */
116 write_nic_byte_E(dev, EPROM_CMD,
117 (EPROM_CMD_PROGRAM << EPROM_CMD_OPERATING_MODE_SHIFT));
118 force_pci_posting(dev);
119 udelay(EPROM_DELAY);
120
121 if (priv->epromtype == EPROM_93c56) {
122 addr_str[7] = addr & 1;
123 addr_str[6] = addr & BIT(1);
124 addr_str[5] = addr & BIT(2);
125 addr_str[4] = addr & BIT(3);
126 addr_str[3] = addr & BIT(4);
127 addr_str[2] = addr & BIT(5);
128 addr_str[1] = addr & BIT(6);
129 addr_str[0] = addr & BIT(7);
130 addr_len = 8;
131 } else {
132 addr_str[5] = addr & 1;
133 addr_str[4] = addr & BIT(1);
134 addr_str[3] = addr & BIT(2);
135 addr_str[2] = addr & BIT(3);
136 addr_str[1] = addr & BIT(4);
137 addr_str[0] = addr & BIT(5);
138 addr_len = 6;
139 }
140 eprom_cs(dev, 1);
141 eprom_ck_cycle(dev);
142 eprom_send_bits_string(dev, read_cmd, 3);
143 eprom_send_bits_string(dev, addr_str, addr_len);
144
145 /*
146 * keep chip pin D to low state while reading.
147 * I'm unsure if it is necessary, but anyway shouldn't hurt
148 */
149 eprom_w(dev, 0);
150
151 for (i = 0; i < 16; i++) {
152 /* eeprom needs a clk cycle between writing opcode&adr
153 * and reading data. (eeprom outs a dummy 0)
154 */
155 eprom_ck_cycle(dev);
156 err = eprom_r(dev);
157 if (err < 0)
158 return err;
159
160 ret |= err << (15 - i);
161 }
162
163 eprom_cs(dev, 0);
164 eprom_ck_cycle(dev);
165
166 /* disable EPROM programming */
167 write_nic_byte_E(dev, EPROM_CMD,
168 (EPROM_CMD_NORMAL << EPROM_CMD_OPERATING_MODE_SHIFT));
169 return ret;
170 }
171