From bcb8173578437175717d820e2eac5e1887467557 Mon Sep 17 00:00:00 2001
From: Steve Markgraf <steve@steve-m.de>
Date: Tue, 9 Oct 2012 01:26:26 +0200
Subject: [PATCH] add support for GSM-R-900

Signed-off-by: Steve Markgraf <steve@steve-m.de>
---
 src/arfcn_freq.cc | 37 ++++++++++++++++++++++++++++++++++---
 src/arfcn_freq.h  |  1 +
 src/kal.cc        |  4 ++--
 3 files changed, 37 insertions(+), 5 deletions(-)

diff --git a/src/arfcn_freq.cc b/src/arfcn_freq.cc
index d8734fd..1c7a2b7 100644
--- a/src/arfcn_freq.cc
+++ b/src/arfcn_freq.cc
@@ -38,6 +38,9 @@ const char *bi_to_str(int bi) {
 		case GSM_850:
 			return "GSM-850";
 
+		case GSM_R_900:
+			return "GSM-R-900";
+
 		case GSM_900:
 			return "GSM-900";
 
@@ -61,6 +64,9 @@ int str_to_bi(char *s) {
 	if(!strcmp(s, "GSM850") || !strcmp(s, "GSM-850") || !strcmp(s, "850"))
 		return GSM_850;
 
+	if(!strcmp(s, "GSM-R") || !strcmp(s, "R-GSM"))
+		return GSM_R_900;
+
 	if(!strcmp(s, "GSM900") || !strcmp(s, "GSM-900") || !strcmp(s, "900"))
 		return GSM_900;
 
@@ -99,9 +105,13 @@ double arfcn_to_freq(int n, int *bi) {
 			*bi = GSM_E_900;
 		return 935e6;
 	}
-	if((975 <= n) && (n <= 1023)) {
-		if(bi)
-			*bi = GSM_E_900;
+	if((955 <= n) && (n <= 1023)) {
+		if(bi) {
+			if (975 <= n)
+				*bi = GSM_E_900;
+			else
+				*bi = GSM_R_900;
+		}
 		return 890.0e6 + 0.2e6 * (n - 1024) + 45.0e6;
 	}
 
@@ -141,6 +151,12 @@ int freq_to_arfcn(double freq, int *bi) {
 		return (int)((freq - 869.2e6) / 0.2e6) + 128;
 	}
 
+	if((921.2e6 <= freq) && (freq <= 925.0e6)) {
+		if(bi)
+			*bi = GSM_R_900;
+		return (int)((freq - 935e6) / 0.2e6) + 1024;
+	}
+
 	if((935.2e6 <= freq) && (freq <= 959.8e6)) {
 		if(bi)
 			*bi = GSM_900;
@@ -181,6 +197,9 @@ int first_chan(int bi) {
 		case GSM_850:
 			return 128;
 
+		case GSM_R_900:
+			return 955;
+
 		case GSM_900:
 			return 1;
 
@@ -211,6 +230,13 @@ int next_chan_loop(int chan, int bi) {
 				return 128;
 			return -1;
 
+		case GSM_R_900:
+			if((955 <= chan) && (chan < 974))
+				return chan + 1;
+			if(chan == 974)
+				return 955;
+			return -1;
+
 		case GSM_900:
 			if((1 <= chan) && (chan < 124))
 				return chan + 1;
@@ -259,6 +285,11 @@ int next_chan(int chan, int bi) {
 				return chan + 1;
 			return -1;
 
+		case GSM_R_900:
+			if((955 <= chan) && (chan < 974))
+				return chan + 1;
+			return -1;
+
 		case GSM_900:
 			if((1 <= chan) && (chan < 124))
 				return chan + 1;
diff --git a/src/arfcn_freq.h b/src/arfcn_freq.h
index 68c91b4..fbd24e6 100644
--- a/src/arfcn_freq.h
+++ b/src/arfcn_freq.h
@@ -28,6 +28,7 @@
 enum {
 	BI_NOT_DEFINED,
 	GSM_850,
+	GSM_R_900,
 	GSM_900,
 	GSM_E_900,
 	DCS_1800,
diff --git a/src/kal.cc b/src/kal.cc
index 6e745d2..5c9483c 100644
--- a/src/kal.cc
+++ b/src/kal.cc
@@ -77,10 +77,10 @@ void usage(char *prog) {
 	printf("\t\t%s <-f frequency | -c channel> [options]\n", basename(prog));
 	printf("\n");
 	printf("Where options are:\n");
-	printf("\t-s\tband to scan (GSM850, GSM900, EGSM, DCS, PCS)\n");
+	printf("\t-s\tband to scan (GSM850, GSM-R, GSM900, EGSM, DCS, PCS)\n");
 	printf("\t-f\tfrequency of nearby GSM base station\n");
 	printf("\t-c\tchannel of nearby GSM base station\n");
-	printf("\t-b\tband indicator (GSM850, GSM900, EGSM, DCS, PCS)\n");
+	printf("\t-b\tband indicator (GSM850, GSM-R, GSM900, EGSM, DCS, PCS)\n");
 	printf("\t-g\tgain in dB\n");
 	printf("\t-d\trtl-sdr device index\n");
 	printf("\t-e\tinitial frequency error in ppm\n");