gsm0808: add function gsm0808_chan_type_to_speech_code()

The permitted speech field used in channel type element (struct
gsm0808_channel_type) uses a different representation as
the type field in the speech codec element (struct
gsm0808_speech_codec)

This patch adds a function to convert from permitted speech to
speech codec type.

Change-Id: Ib26a9c20864459b2baaa04f49b6e7902ba44b7cb
This commit is contained in:
Philipp Maier 2017-06-02 13:22:34 +02:00 committed by Harald Welte
parent a9b9276948
commit 3149b0d076
3 changed files with 40 additions and 0 deletions

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@ -71,3 +71,5 @@ uint8_t gsm0808_enc_cell_id_list(struct msgb *msg,
/* Decode Cell Identifier List element */
int gsm0808_dec_cell_id_list(struct gsm0808_cell_id_list *cil,
const uint8_t *elem, uint8_t len);
int gsm0808_chan_type_to_speech_code(uint8_t perm_spch);

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@ -645,4 +645,41 @@ int gsm0808_dec_cell_id_list(struct gsm0808_cell_id_list *cil,
return (int)(elem - old_elem);
}
/*! \brief Convert the representation of the permitted speech codec identifier
* that is used in struct gsm0808_channel_type to the speech codec
* representation we use in struct gsm0808_speech_codec.
* \param[in] perm_spch to be converted (see also gsm0808_permitted_speech)
* \returns GSM speech codec type; negative on error */
int gsm0808_chan_type_to_speech_codec(uint8_t perm_spch)
{
/*! The speech codec type, which is used in the channel type field to
* signal the permitted speech versions (codecs) has a different
* encoding than the type field in the speech codec type element
* (See also 3GPP TS 48.008, 3.2.2.11 and 3.2.2.103) */
switch (perm_spch) {
case GSM0808_PERM_FR1:
return GSM0808_SCT_FR1;
case GSM0808_PERM_FR2:
return GSM0808_SCT_FR2;
case GSM0808_PERM_FR3:
return GSM0808_SCT_FR3;
case GSM0808_PERM_FR4:
return GSM0808_SCT_FR4;
case GSM0808_PERM_FR5:
return GSM0808_SCT_FR5;
case GSM0808_PERM_HR1:
return GSM0808_SCT_HR1;
case GSM0808_PERM_HR3:
return GSM0808_SCT_HR3;
case GSM0808_PERM_HR4:
return GSM0808_SCT_HR4;
case GSM0808_PERM_HR6:
return GSM0808_SCT_HR6;
}
/* Invalid input */
return -EINVAL;
}
/*! @} */

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@ -162,6 +162,7 @@ gsm0808_enc_encrypt_info;
gsm0808_dec_encrypt_info;
gsm0808_enc_cell_id_list;
gsm0808_dec_cell_id_list;
gsm0808_convert_to_speech_codec_type;
gsm0858_rsl_ul_meas_enc;