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