onewire: make those onewire functions more general and add temperature reading wrapper function

dev/onewire.c

-#include "persistent_mac.h"
+#include "onewire.h"
 #include "../sockitowm/ownet.h"
 #include "../sockitowm/findtype.h"
 
-#define MAX_DEV1WIRE 8
 #define DEBUG_PMAC 0
 
-/* 0 = success, -1 = error */
-int get_persistent_mac(unsigned char* mac)
+uint8_t FamilySN[MAX_DEV1WIRE][8];
+uint8_t devsnum;
+uint8_t found_msk;
+
+void own_scanbus(uint8_t portnum)
 {
-  unsigned char FamilySN[MAX_DEV1WIRE][8];
-  unsigned char read_buffer[32];
-  unsigned char portnum = ONEWIRE_PORT;
-  int i, devices, out;
-  
   // Find the device(s)
-  devices = 0;
-  devices += FindDevices(portnum, &FamilySN[devices], 0x28, MAX_DEV1WIRE - devices); /* Temperature 28 sensor (SPEC) */
-  devices += FindDevices(portnum, &FamilySN[devices], 0x42, MAX_DEV1WIRE - devices); /* Temperature 42 sensor (SCU) */
-  devices += FindDevices(portnum, &FamilySN[devices], 0x43, MAX_DEV1WIRE - devices); /* EEPROM */
+  found_msk = 0;
+  devsnum = 0;
+  devsnum += FindDevices(portnum, &FamilySN[devsnum], 0x28, MAX_DEV1WIRE - devsnum); /* Temperature 28 sensor (SPEC) */
+  if(devsnum>0) found_msk |= FOUND_DS18B20;
+  devsnum += FindDevices(portnum, &FamilySN[devsnum], 0x42, MAX_DEV1WIRE - devsnum); /* Temperature 42 sensor (SCU) */
+  devsnum += FindDevices(portnum, &FamilySN[devsnum], 0x43, MAX_DEV1WIRE - devsnum); /* EEPROM */
 #if DEBUG_PMAC
-  mprintf("Found %d onewire devices\n", devices);
+  mprintf("Found %d onewire devices\n", devsnum);
 #endif
+}
+
+int16_t own_readtemp(uint8_t portnum, int16_t *temp, int16_t *t_frac)
+{
+  if(!(found_msk & FOUND_DS18B20))
+    return -1;
+  if(ReadTemperature28(portnum, FamilySN[0], temp))
+  {
+    *t_frac = 5000*(!!(*temp & 0x08)) + 2500*(!!(*temp & 0x04)) + 1250*(!!(*temp & 0x02)) +
+              625*(!!(*temp & 0x01));
+    *t_frac = *t_frac/100 + (*t_frac%100)/50;
+    *temp >>= 4;
+    return 0;
+  }
+  return -1;
+}
+
+/* 0 = success, -1 = error */
+int8_t get_persistent_mac(uint8_t portnum, uint8_t* mac)
+{
+  uint8_t read_buffer[32];
+  uint8_t i;
+  int8_t out;
   
   out = -1;
+
+  if(devsnum == 0) return out;
   
-  for (i = 0; i < devices; ++i) {
-#if DEBUG_PMAC
+  for (i = 0; i < devsnum; ++i) {
+//#if DEBUG_PMAC
     mprintf("Found device: %x:%x:%x:%x:%x:%x:%x:%x\n", 
       FamilySN[i][7], FamilySN[i][6], FamilySN[i][5], FamilySN[i][4],
       FamilySN[i][3], FamilySN[i][2], FamilySN[i][1], FamilySN[i][0]);
-#endif
+//#endif
 
     /* If there is a temperature sensor, use it for the low three MAC values */
     if (FamilySN[i][0] == 0x28 || FamilySN[i][0] == 0x42) {
@@ -67,17 +91,13 @@ int get_persistent_mac(unsigned char* mac)
 }
 
 /* 0 = success, -1 = error */
-int set_persistent_mac(unsigned char* mac)
+int8_t set_persistent_mac(uint8_t portnum, uint8_t* mac)
 {
-  unsigned char FamilySN[MAX_DEV1WIRE][8];
-  unsigned char write_buffer[32];
-  unsigned char portnum = ONEWIRE_PORT;
-  int i, devices;
+  uint8_t FamilySN[1][8];
+  uint8_t write_buffer[32];
 
-  // Find the device(s)
-  devices = FindDevices(portnum, &FamilySN[0], 0x43, MAX_DEV1WIRE); /* EEPROM */
-  
-  if (devices == 0) return -1;
+  // Find the device (only the first one, we won't write MAC to all EEPROMs out there, right?)
+  if( FindDevices(portnum, &FamilySN[0], 0x43, 1) == 0) return -1;
   
   memset(write_buffer, 0, sizeof(write_buffer));
   memcpy(write_buffer, mac, 6);
@@ -88,7 +108,7 @@ int set_persistent_mac(unsigned char* mac)
   
   /* Write the last EEPROM with the MAC */
   owLevel(portnum, MODE_NORMAL);
-  if (Write43(portnum, FamilySN[devices-1], EEPROM_MAC_PAGE, &write_buffer) == TRUE)
+  if (Write43(portnum, FamilySN[0], EEPROM_MAC_PAGE, &write_buffer) == TRUE)
     return 0;
   
   return -1;

include/onewire.h

@@ -3,9 +3,14 @@
 
 #define ONEWIRE_PORT 0
 #define EEPROM_MAC_PAGE 0
+#define MAX_DEV1WIRE 8
 
+#define FOUND_DS18B20 0x01
+
+void own_scanbus(uint8_t portnum);
+int16_t own_readtemp(uint8_t portnum, int16_t *temp, int16_t *t_frac);
 /* 0 = success, -1 = error */
-int get_persistent_mac(unsigned char* mac);
-int set_persistent_mac(unsigned char* mac);
+int8_t get_persistent_mac(uint8_t portnum, uint8_t* mac);
+int8_t set_persistent_mac(uint8_t portnum, uint8_t* mac);
 
 #endif

shell/cmd_mac.c

@@ -4,6 +4,7 @@
 
 #include "softpll_ng.h"
 #include "shell.h"
+#include "onewire.h"
 #include "../lib/ipv4.h"
 
 static decode_mac(const char *str, unsigned char* mac) {
@@ -27,14 +28,14 @@ int cmd_mac(const char *args[])
   } else if (!strcasecmp(args[0], "getp")) {
     /* get persistent MAC */
     get_mac_addr(mac);
-    get_persistent_mac(mac);
+    get_persistent_mac(ONEWIRE_PORT, mac);
   } else if (!strcasecmp(args[0], "set") && args[1]) {
     decode_mac(args[1], mac);
     set_mac_addr(mac);
     pfilter_init_default();
   } else if (!strcasecmp(args[0], "setp") && args[1]) {
     decode_mac(args[1], mac);
-    set_persistent_mac(mac);
+    set_persistent_mac(ONEWIRE_PORT, mac);
   } else {
     return -EINVAL;
   }

wrc_main.c

@@ -13,7 +13,7 @@
 #include "i2c.h"
 //#include "eeprom.h"
 #include "softpll_ng.h"
-#include "persistent_mac.h"
+#include "onewire.h"
 #include "lib/ipv4.h"
 
 #include "wrc_ptp.h"
@@ -50,7 +50,8 @@ void wrc_initialize()
   mac_addr[4] = 0xAD;
   mac_addr[5] = 0x42;
   
-  if (get_persistent_mac(mac_addr) == -1) {
+  own_scanbus(ONEWIRE_PORT);
+  if (get_persistent_mac(ONEWIRE_PORT, mac_addr) == -1) {
     mprintf("Unable to determine MAC address\n");
   }