gsm0808_utils: fix gsm48 multirate configuration generator
The function gsm0808_sc_cfg_from_gsm48_mr_cfg() takes an S15 to S0
bitmask and converts that bitmask into an AMR multirate configuration
struct.
Unfortunately the current implementation implements 3GPP TS 28.062,
Table 7.11.3.1.3-2 wrongly in some aspects. Lets fix this.
- Fix wrong interpretation of the bitpatterns
- 5,15K is invalid and must never be selected
- Make sure that no more than 4 rates are selected in the active set
- Extend unit-test
Change-Id: I6fd7f4073b84093742c322752f2fd878d1071e15
Related: SYS#4470
diff --git a/include/osmocom/gsm/protocol/gsm_08_08.h b/include/osmocom/gsm/protocol/gsm_08_08.h
index 67dc6ee..aa01ee5 100644
--- a/include/osmocom/gsm/protocol/gsm_08_08.h
+++ b/include/osmocom/gsm/protocol/gsm_08_08.h
@@ -553,6 +553,20 @@
GSM0808_SC_CFG_DEFAULT_AMR_12_2 = 0xc082
};
+/*! Single speech codec configurations broken down by reate.
+ * See also: 3GPP TS 28.062, Table 7.11.3.1.3-2: Preferred Configurations for
+ * the Adaptive Multi-Rate Codec Types. */
+enum gsm0808_speech_codec_rate {
+ GSM0808_SC_CFG_AMR_4_75 = 0x0001,
+ GSM0808_SC_CFG_AMR_4_75_5_90_7_40_12_20 = 0x0002,
+ GSM0808_SC_CFG_AMR_5_90 = 0x0004,
+ GSM0808_SC_CFG_AMR_6_70 = 0x0008,
+ GSM0808_SC_CFG_AMR_7_40 = 0x0010,
+ GSM0808_SC_CFG_AMR_7_95 = 0x0020,
+ GSM0808_SC_CFG_AMR_10_2 = 0x0040,
+ GSM0808_SC_CFG_AMR_12_2 = 0x0080,
+};
+
/* 3GPP TS 48.008 3.2.2.103 Speech Codec List */
#define SPEECH_CODEC_MAXLEN 255
struct gsm0808_speech_codec_list {