create lock files to choose mpsse index in order to support two lora cards1.7.0-mts

1 files changed, 30 insertions, 9 deletions

diff --git a/libloragw/src/loragw_spi.ftdi.c b/libloragw/src/loragw_spi.ftdi.c
index d57e764..4f0928a 100644
--- a/libloragw/src/loragw_spi.ftdi.c
+++ b/libloragw/src/loragw_spi.ftdi.c
@@ -28,6 +28,7 @@ Maintainer: Sylvain Miermont
 
 #include <sys/types.h>
 #include <linux/limits.h>
+#include <sys/file.h>
 #include <mpsse.h>
 
 #include "loragw_spi.h"
@@ -60,6 +61,8 @@ Maintainer: Sylvain Miermont
 	#define PID		0x6010
 #endif
 
+#define LCK_SPI0 "/var/lock/LCK..spi0"
+#define LCK_SPI1 "/var/lock/LCK..spi1"
 
 /* -------------------------------------------------------------------------- */
 /* --- PUBLIC FUNCTIONS DEFINITION ------------------------------------------ */
@@ -78,15 +81,33 @@ int lgw_spi_open(void **spi_target_ptr) {
 	CHECK_NULL(spi_target_ptr); /* cannot be null, must point on a void pointer (*spi_target_ptr can be null) */
 	
 	/* try to open the first available FTDI device matching VID/PID parameters */
-	mpsse = OpenIndex(VID,PID,SPI0, SIX_MHZ, MSB, IFACE_A, NULL, NULL, 0);
-	if (mpsse == NULL) {
-		DEBUG_MSG("ERROR: MPSSE OPEN FUNCTION RETURNED NULL\n");
-		return LGW_SPI_ERROR;
-	}
-	if (mpsse->open != 1) {
-		DEBUG_MSG("ERROR: MPSSE OPEN FUNCTION FAILED\n");
-		return LGW_SPI_ERROR;
-	}
+	    int i = 0;
+
+    int fd = open(LCK_SPI0, O_RDWR | O_CREAT, 0666); // open or create lockfile
+    //check open success...
+    int rc = flock(fd, LOCK_EX | LOCK_NB); // grab exclusive lock, fail if can't obtain.
+    if (rc)
+    {
+        i = 1;
+        fd = open(LCK_SPI1, O_RDWR | O_CREAT, 0666); // open or create lockfile
+        //check open success...
+        rc = flock(fd, LOCK_EX | LOCK_NB); // grab exclusive lock, fail if can't obtain.
+
+        if (rc) {
+            DEBUG_MSG("ERROR: FAILED TO OBTAIN LOCK ON SPI DEVICE\n");
+            return LGW_SPI_ERROR;
+        }
+    }
+
+    mpsse = OpenIndex(VID,PID,SPI0, SIX_MHZ, MSB, IFACE_A, NULL, NULL, i);
+    if (mpsse == NULL) {
+        DEBUG_MSG("ERROR: MPSSE OPEN FUNCTION RETURNED NULL\n");
+        return LGW_SPI_ERROR;
+    }
+    if (mpsse->open != 1) {
+        DEBUG_MSG("ERROR: MPSSE OPEN FUNCTION FAILED\n");
+        return LGW_SPI_ERROR;
+    }
 	
 	/* toggle pin ADBUS5 of the FT2232H */
 	/* On the Semtech reference board, it resets the SX1301 */