summaryrefslogtreecommitdiff
path: root/drivers/media/dvb/ttpci/ttpci-eeprom.c
diff options
context:
space:
mode:
Diffstat (limited to 'drivers/media/dvb/ttpci/ttpci-eeprom.c')
-rw-r--r--drivers/media/dvb/ttpci/ttpci-eeprom.c146
1 files changed, 146 insertions, 0 deletions
diff --git a/drivers/media/dvb/ttpci/ttpci-eeprom.c b/drivers/media/dvb/ttpci/ttpci-eeprom.c
new file mode 100644
index 000000000000..e9a8457b0727
--- /dev/null
+++ b/drivers/media/dvb/ttpci/ttpci-eeprom.c
@@ -0,0 +1,146 @@
+/*
+ Retrieve encoded MAC address from 24C16 serial 2-wire EEPROM,
+ decode it and store it in the associated adapter struct for
+ use by dvb_net.c
+
+ This card appear to have the 24C16 write protect held to ground,
+ thus permitting normal read/write operation. Theoretically it
+ would be possible to write routines to burn a different (encoded)
+ MAC address into the EEPROM.
+
+ Robert Schlabbach GMX
+ Michael Glaum KVH Industries
+ Holger Waechtler Convergence
+
+ Copyright (C) 2002-2003 Ralph Metzler <rjkm@metzlerbros.de>
+ Metzler Brothers Systementwicklung GbR
+
+ This program is free software; you can redistribute it and/or modify
+ it under the terms of the GNU General Public License as published by
+ the Free Software Foundation; either version 2 of the License, or
+ (at your option) any later version.
+
+ This program is distributed in the hope that it will be useful,
+ but WITHOUT ANY WARRANTY; without even the implied warranty of
+ MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+ GNU General Public License for more details.
+
+ You should have received a copy of the GNU General Public License
+ along with this program; if not, write to the Free Software
+ Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
+
+*/
+
+#include <asm/errno.h>
+#include <linux/init.h>
+#include <linux/module.h>
+#include <linux/string.h>
+#include <linux/i2c.h>
+
+
+#if 1
+#define dprintk(x...) do { printk(x); } while (0)
+#else
+#define dprintk(x...) do { } while (0)
+#endif
+
+
+static int check_mac_tt(u8 *buf)
+{
+ int i;
+ u16 tmp = 0xffff;
+
+ for (i = 0; i < 8; i++) {
+ tmp = (tmp << 8) | ((tmp >> 8) ^ buf[i]);
+ tmp ^= (tmp >> 4) & 0x0f;
+ tmp ^= (tmp << 12) ^ ((tmp & 0xff) << 5);
+ }
+ tmp ^= 0xffff;
+ return (((tmp >> 8) ^ buf[8]) | ((tmp & 0xff) ^ buf[9]));
+}
+
+static int getmac_tt(u8 * decodedMAC, u8 * encodedMAC)
+{
+ u8 xor[20] = { 0x72, 0x23, 0x68, 0x19, 0x5c, 0xa8, 0x71, 0x2c,
+ 0x54, 0xd3, 0x7b, 0xf1, 0x9E, 0x23, 0x16, 0xf6,
+ 0x1d, 0x36, 0x64, 0x78};
+ u8 data[20];
+ int i;
+
+ /* In case there is a sig check failure have the orig contents available */
+ memcpy(data, encodedMAC, 20);
+
+ for (i = 0; i < 20; i++)
+ data[i] ^= xor[i];
+ for (i = 0; i < 10; i++)
+ data[i] = ((data[2 * i + 1] << 8) | data[2 * i])
+ >> ((data[2 * i + 1] >> 6) & 3);
+
+ if (check_mac_tt(data))
+ return -ENODEV;
+
+ decodedMAC[0] = data[2]; decodedMAC[1] = data[1]; decodedMAC[2] = data[0];
+ decodedMAC[3] = data[6]; decodedMAC[4] = data[5]; decodedMAC[5] = data[4];
+ return 0;
+}
+
+static int ttpci_eeprom_read_encodedMAC(struct i2c_adapter *adapter, u8 * encodedMAC)
+{
+ int ret;
+ u8 b0[] = { 0xcc };
+
+ struct i2c_msg msg[] = {
+ { .addr = 0x50, .flags = 0, .buf = b0, .len = 1 },
+ { .addr = 0x50, .flags = I2C_M_RD, .buf = encodedMAC, .len = 20 }
+ };
+
+ /* dprintk("%s\n", __FUNCTION__); */
+
+ ret = i2c_transfer(adapter, msg, 2);
+
+ if (ret != 2) /* Assume EEPROM isn't there */
+ return (-ENODEV);
+
+ return 0;
+}
+
+
+int ttpci_eeprom_parse_mac(struct i2c_adapter *adapter, u8 *proposed_mac)
+{
+ int ret, i;
+ u8 encodedMAC[20];
+ u8 decodedMAC[6];
+
+ ret = ttpci_eeprom_read_encodedMAC(adapter, encodedMAC);
+
+ if (ret != 0) { /* Will only be -ENODEV */
+ dprintk("Couldn't read from EEPROM: not there?\n");
+ memset(proposed_mac, 0, 6);
+ return ret;
+ }
+
+ ret = getmac_tt(decodedMAC, encodedMAC);
+ if( ret != 0 ) {
+ dprintk("adapter failed MAC signature check\n");
+ dprintk("encoded MAC from EEPROM was " );
+ for(i=0; i<19; i++) {
+ dprintk( "%.2x:", encodedMAC[i]);
+ }
+ dprintk("%.2x\n", encodedMAC[19]);
+ memset(proposed_mac, 0, 6);
+ return ret;
+ }
+
+ memcpy(proposed_mac, decodedMAC, 6);
+ dprintk("adapter has MAC addr = %.2x:%.2x:%.2x:%.2x:%.2x:%.2x\n",
+ decodedMAC[0], decodedMAC[1], decodedMAC[2],
+ decodedMAC[3], decodedMAC[4], decodedMAC[5]);
+ return 0;
+}
+
+EXPORT_SYMBOL(ttpci_eeprom_parse_mac);
+
+MODULE_LICENSE("GPL");
+MODULE_AUTHOR("Ralph Metzler, Marcus Metzler, others");
+MODULE_DESCRIPTION("Decode dvb_net MAC address from EEPROM of PCI DVB cards "
+ "made by Siemens, Technotrend, Hauppauge");