1 // SPDX-License-Identifier: GPL-2.0
2 /*
3 * Linux driver for digital TV devices equipped with B2C2 FlexcopII(b)/III
4 * flexcop-eeprom.c - eeprom access methods (currently only MAC address reading)
5 * see flexcop.c for copyright information
6 */
7 #include "flexcop.h"
8
9 #if 0
10 /*EEPROM (Skystar2 has one "24LC08B" chip on board) */
11 static int eeprom_write(struct adapter *adapter, u16 addr, u8 *buf, u16 len)
12 {
13 return flex_i2c_write(adapter, 0x20000000, 0x50, addr, buf, len);
14 }
15
16 static int eeprom_lrc_write(struct adapter *adapter, u32 addr,
17 u32 len, u8 *wbuf, u8 *rbuf, int retries)
18 {
19 int i;
20
21 for (i = 0; i < retries; i++) {
22 if (eeprom_write(adapter, addr, wbuf, len) == len) {
23 if (eeprom_lrc_read(adapter, addr, len, rbuf, retries) == 1)
24 return 1;
25 }
26 }
27 return 0;
28 }
29
30 /* These functions could be used to unlock SkyStar2 cards. */
31
32 static int eeprom_writeKey(struct adapter *adapter, u8 *key, u32 len)
33 {
34 u8 rbuf[20];
35 u8 wbuf[20];
36
37 if (len != 16)
38 return 0;
39
40 memcpy(wbuf, key, len);
41 wbuf[16] = 0;
42 wbuf[17] = 0;
43 wbuf[18] = 0;
44 wbuf[19] = calc_lrc(wbuf, 19);
45 return eeprom_lrc_write(adapter, 0x3e4, 20, wbuf, rbuf, 4);
46 }
47
48 static int eeprom_readKey(struct adapter *adapter, u8 *key, u32 len)
49 {
50 u8 buf[20];
51
52 if (len != 16)
53 return 0;
54
55 if (eeprom_lrc_read(adapter, 0x3e4, 20, buf, 4) == 0)
56 return 0;
57
58 memcpy(key, buf, len);
59 return 1;
60 }
61
62 static char eeprom_set_mac_addr(struct adapter *adapter, char type, u8 *mac)
63 {
64 u8 tmp[8];
65
66 if (type != 0) {
67 tmp[0] = mac[0];
68 tmp[1] = mac[1];
69 tmp[2] = mac[2];
70 tmp[3] = mac[5];
71 tmp[4] = mac[6];
72 tmp[5] = mac[7];
73 } else {
74 tmp[0] = mac[0];
75 tmp[1] = mac[1];
76 tmp[2] = mac[2];
77 tmp[3] = mac[3];
78 tmp[4] = mac[4];
79 tmp[5] = mac[5];
80 }
81
82 tmp[6] = 0;
83 tmp[7] = calc_lrc(tmp, 7);
84
85 if (eeprom_write(adapter, 0x3f8, tmp, 8) == 8)
86 return 1;
87 return 0;
88 }
89
90 static int flexcop_eeprom_read(struct flexcop_device *fc,
91 u16 addr, u8 *buf, u16 len)
92 {
93 return fc->i2c_request(fc,FC_READ,FC_I2C_PORT_EEPROM,0x50,addr,buf,len);
94 }
95
96 #endif
97
calc_lrc(u8 * buf,int len)98 static u8 calc_lrc(u8 *buf, int len)
99 {
100 int i;
101 u8 sum = 0;
102 for (i = 0; i < len; i++)
103 sum = sum ^ buf[i];
104 return sum;
105 }
106
flexcop_eeprom_request(struct flexcop_device * fc,flexcop_access_op_t op,u16 addr,u8 * buf,u16 len,int retries)107 static int flexcop_eeprom_request(struct flexcop_device *fc,
108 flexcop_access_op_t op, u16 addr, u8 *buf, u16 len, int retries)
109 {
110 int i,ret = 0;
111 u8 chipaddr = 0x50 | ((addr >> 8) & 3);
112 for (i = 0; i < retries; i++) {
113 ret = fc->i2c_request(&fc->fc_i2c_adap[1], op, chipaddr,
114 addr & 0xff, buf, len);
115 if (ret == 0)
116 break;
117 }
118 return ret;
119 }
120
flexcop_eeprom_lrc_read(struct flexcop_device * fc,u16 addr,u8 * buf,u16 len,int retries)121 static int flexcop_eeprom_lrc_read(struct flexcop_device *fc, u16 addr,
122 u8 *buf, u16 len, int retries)
123 {
124 int ret = flexcop_eeprom_request(fc, FC_READ, addr, buf, len, retries);
125 if (ret == 0)
126 if (calc_lrc(buf, len - 1) != buf[len - 1])
127 ret = -EINVAL;
128 return ret;
129 }
130
131 /* JJ's comment about extended == 1: it is not presently used anywhere but was
132 * added to the low-level functions for possible support of EUI64 */
flexcop_eeprom_check_mac_addr(struct flexcop_device * fc,int extended)133 int flexcop_eeprom_check_mac_addr(struct flexcop_device *fc, int extended)
134 {
135 u8 buf[8];
136 int ret = 0;
137
138 if ((ret = flexcop_eeprom_lrc_read(fc,0x3f8,buf,8,4)) == 0) {
139 if (extended != 0) {
140 err("TODO: extended (EUI64) MAC addresses aren't completely supported yet");
141 ret = -EINVAL;
142 } else
143 memcpy(fc->dvb_adapter.proposed_mac,buf,6);
144 }
145 return ret;
146 }
147 EXPORT_SYMBOL(flexcop_eeprom_check_mac_addr);
148