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) */
10static 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
15static int eeprom_lrc_write(struct adapter *adapter, u32 addr,
16		u32 len, u8 *wbuf, u8 *rbuf, int retries)
17{
18int i;
19
20for (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
31static 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
47static 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
61static 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
89static 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
97static 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
106static 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
120static 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 */
132int 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}
147EXPORT_SYMBOL(flexcop_eeprom_check_mac_addr);
148