flexcop-eeprom.c

  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) */
 11static 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
 16static int eeprom_lrc_write(struct adapter *adapter, u32 addr,
 17		u32 len, u8 *wbuf, u8 *rbuf, int retries)
 18{
 19int i;
 20
 21for (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
 32static 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
 48static 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
 62static 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
 90static 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
 98static 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
107static 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
121static 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 */
133int 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}
147EXPORT_SYMBOL(flexcop_eeprom_check_mac_addr);