common/b2c2/flexcop-eeprom.c

0001 // SPDX-License-Identifier: GPL-2.0
0002 /*
0003  * Linux driver for digital TV devices equipped with B2C2 FlexcopII(b)/III
0004  * flexcop-eeprom.c - eeprom access methods (currently only MAC address reading)
0005  * see flexcop.c for copyright information
0006  */
0007 #include "flexcop.h"
0008
0009 #if 0
0010 /*EEPROM (Skystar2 has one "24LC08B" chip on board) */
0011 static int eeprom_write(struct adapter *adapter, u16 addr, u8 *buf, u16 len)
0012 {
0013     return flex_i2c_write(adapter, 0x20000000, 0x50, addr, buf, len);
0014 }
0015
0016 static int eeprom_lrc_write(struct adapter *adapter, u32 addr,
0017         u32 len, u8 *wbuf, u8 *rbuf, int retries)
0018 {
0019 int i;
0020
0021 for (i = 0; i < retries; i++) {
0022     if (eeprom_write(adapter, addr, wbuf, len) == len) {
0023         if (eeprom_lrc_read(adapter, addr, len, rbuf, retries) == 1)
0024             return 1;
0025         }
0026     }
0027     return 0;
0028 }
0029
0030 /* These functions could be used to unlock SkyStar2 cards. */
0031
0032 static int eeprom_writeKey(struct adapter *adapter, u8 *key, u32 len)
0033 {
0034     u8 rbuf[20];
0035     u8 wbuf[20];
0036
0037     if (len != 16)
0038         return 0;
0039
0040     memcpy(wbuf, key, len);
0041     wbuf[16] = 0;
0042     wbuf[17] = 0;
0043     wbuf[18] = 0;
0044     wbuf[19] = calc_lrc(wbuf, 19);
0045     return eeprom_lrc_write(adapter, 0x3e4, 20, wbuf, rbuf, 4);
0046 }
0047
0048 static int eeprom_readKey(struct adapter *adapter, u8 *key, u32 len)
0049 {
0050     u8 buf[20];
0051
0052     if (len != 16)
0053         return 0;
0054
0055     if (eeprom_lrc_read(adapter, 0x3e4, 20, buf, 4) == 0)
0056         return 0;
0057
0058     memcpy(key, buf, len);
0059     return 1;
0060 }
0061
0062 static char eeprom_set_mac_addr(struct adapter *adapter, char type, u8 *mac)
0063 {
0064     u8 tmp[8];
0065
0066     if (type != 0) {
0067         tmp[0] = mac[0];
0068         tmp[1] = mac[1];
0069         tmp[2] = mac[2];
0070         tmp[3] = mac[5];
0071         tmp[4] = mac[6];
0072         tmp[5] = mac[7];
0073     } else {
0074         tmp[0] = mac[0];
0075         tmp[1] = mac[1];
0076         tmp[2] = mac[2];
0077         tmp[3] = mac[3];
0078         tmp[4] = mac[4];
0079         tmp[5] = mac[5];
0080     }
0081
0082     tmp[6] = 0;
0083     tmp[7] = calc_lrc(tmp, 7);
0084
0085     if (eeprom_write(adapter, 0x3f8, tmp, 8) == 8)
0086         return 1;
0087     return 0;
0088 }
0089
0090 static int flexcop_eeprom_read(struct flexcop_device *fc,
0091         u16 addr, u8 *buf, u16 len)
0092 {
0093     return fc->i2c_request(fc,FC_READ,FC_I2C_PORT_EEPROM,0x50,addr,buf,len);
0094 }
0095
0096 #endif
0097
0098 static u8 calc_lrc(u8 *buf, int len)
0099 {
0100     int i;
0101     u8 sum = 0;
0102     for (i = 0; i < len; i++)
0103         sum = sum ^ buf[i];
0104     return sum;
0105 }
0106
0107 static int flexcop_eeprom_request(struct flexcop_device *fc,
0108     flexcop_access_op_t op, u16 addr, u8 *buf, u16 len, int retries)
0109 {
0110     int i,ret = 0;
0111     u8 chipaddr =  0x50 | ((addr >> 8) & 3);
0112     for (i = 0; i < retries; i++) {
0113         ret = fc->i2c_request(&fc->fc_i2c_adap[1], op, chipaddr,
0114             addr & 0xff, buf, len);
0115         if (ret == 0)
0116             break;
0117     }
0118     return ret;
0119 }
0120
0121 static int flexcop_eeprom_lrc_read(struct flexcop_device *fc, u16 addr,
0122         u8 *buf, u16 len, int retries)
0123 {
0124     int ret = flexcop_eeprom_request(fc, FC_READ, addr, buf, len, retries);
0125     if (ret == 0)
0126         if (calc_lrc(buf, len - 1) != buf[len - 1])
0127             ret = -EINVAL;
0128     return ret;
0129 }
0130
0131 /* JJ's comment about extended == 1: it is not presently used anywhere but was
0132  * added to the low-level functions for possible support of EUI64 */
0133 int flexcop_eeprom_check_mac_addr(struct flexcop_device *fc, int extended)
0134 {
0135     u8 buf[8];
0136     int ret = 0;
0137
0138     if ((ret = flexcop_eeprom_lrc_read(fc,0x3f8,buf,8,4)) == 0) {
0139         if (extended != 0) {
0140             err("TODO: extended (EUI64) MAC addresses aren't completely supported yet");
0141             ret = -EINVAL;
0142         } else
0143             memcpy(fc->dvb_adapter.proposed_mac,buf,6);
0144     }
0145     return ret;
0146 }
0147 EXPORT_SYMBOL(flexcop_eeprom_check_mac_addr);