1 files changed, 147 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 00000000000..7dd54b3026a
--- /dev/null
+++ b/drivers/media/dvb/ttpci/ttpci-eeprom.c
@@ -0,0 +1,147 @@
+/*
+    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>
+
+#include "ttpci-eeprom.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", __func__); */
+
+        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");