LXR linux/drivers/media/common/b2c2/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);
 148