1 // SPDX-License-Identifier: GPL-2.0-or-later
3     Retrieve encoded MAC address from 24C16 serial 2-wire EEPROM,
10     MAC address into the EEPROM.
16     Copyright (C) 2002-2003 Ralph Metzler <rjkm@metzlerbros.de>
29 #include "ttpci-eeprom.h"
57 	u8 data[20];  in getmac_tt()  local
61 	memcpy(data, encodedMAC, 20);  in getmac_tt()
64 		data[i] ^= xor[i];  in getmac_tt()
66 		data[i] = ((data[2 * i + 1] << 8) | data[2 * i])  in getmac_tt()
67 			>> ((data[2 * i + 1] >> 6) & 3);  in getmac_tt()
69 	if (check_mac_tt(data))  in getmac_tt()
70 		return -ENODEV;  in getmac_tt()
72 	decodedMAC[0] = data[2]; decodedMAC[1] = data[1]; decodedMAC[2] = data[0];  in getmac_tt()
73 	decodedMAC[3] = data[6]; decodedMAC[4] = data[5]; decodedMAC[5] = data[4];  in getmac_tt()
82 	u8 data[20];  in ttpci_eeprom_decode_mac()  local
85 	memcpy(data, encodedMAC, 20);  in ttpci_eeprom_decode_mac()
88 		data[i] ^= xor[i];  in ttpci_eeprom_decode_mac()
90 		data[i] = ((data[2 * i + 1] << 8) | data[2 * i])  in ttpci_eeprom_decode_mac()
91 			>> ((data[2 * i + 1] >> 6) & 3);  in ttpci_eeprom_decode_mac()
93 	if (check_mac_tt(data))  in ttpci_eeprom_decode_mac()
94 		return -ENODEV;  in ttpci_eeprom_decode_mac()
96 	decodedMAC[0] = data[2];  in ttpci_eeprom_decode_mac()
97 	decodedMAC[1] = data[1];  in ttpci_eeprom_decode_mac()
98 	decodedMAC[2] = data[0];  in ttpci_eeprom_decode_mac()
99 	decodedMAC[3] = data[6];  in ttpci_eeprom_decode_mac()
100 	decodedMAC[4] = data[5];  in ttpci_eeprom_decode_mac()
101 	decodedMAC[5] = data[4];  in ttpci_eeprom_decode_mac()
120 	if (ret != 2)		/* Assume EEPROM isn't there */  in ttpci_eeprom_read_encodedMAC()
121 		return (-ENODEV);  in ttpci_eeprom_read_encodedMAC()
135 	if (ret != 0) {		/* Will only be -ENODEV */  in ttpci_eeprom_parse_mac()
136 		dprintk("Couldn't read from EEPROM: not there?\n");  in ttpci_eeprom_parse_mac()
144 		dprintk("encoded MAC from EEPROM was %*phC",  in ttpci_eeprom_parse_mac()
159 MODULE_DESCRIPTION("Decode dvb_net MAC address from EEPROM of PCI DVB cards made by Siemens, Techno…