drivers/media/dvb/b2c2/flexcop-eeprom.c

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