From: Johannes Berg <[email protected]> IEEE 802.11-2016 extended the VHT capability fields to allow indicating the number of spatial streams depending on the actually used bandwidth, add support for decoding this.
Signed-off-by: Johannes Berg <[email protected]> --- include/linux/ieee80211.h | 105 +++++++++++++++++++++++++++++++++++++++++++++- 1 file changed, 103 insertions(+), 2 deletions(-) diff --git a/include/linux/ieee80211.h b/include/linux/ieee80211.h index 4a7200c6c9ea..c51d309a45e7 100644 --- a/include/linux/ieee80211.h +++ b/include/linux/ieee80211.h @@ -1457,13 +1457,16 @@ struct ieee80211_ht_operation { * STA can receive. Rate expressed in units of 1 Mbps. * If this field is 0 this value should not be used to * consider the highest RX data rate supported. - * The top 3 bits of this field are reserved. + * The top 3 bits of this field indicate the Maximum NSTS,total + * (a beamformee capability.) * @tx_mcs_map: TX MCS map 2 bits for each stream, total 8 streams * @tx_highest: Indicates highest long GI VHT PPDU data rate * STA can transmit. Rate expressed in units of 1 Mbps. * If this field is 0 this value should not be used to * consider the highest TX data rate supported. - * The top 3 bits of this field are reserved. + * The top 2 bits of this field are reserved, the + * 3rd bit from the top indiciates VHT Extended NSS BW + * Capability. */ struct ieee80211_vht_mcs_info { __le16 rx_mcs_map; @@ -1472,6 +1475,13 @@ struct ieee80211_vht_mcs_info { __le16 tx_highest; } __packed; +/* for rx_highest */ +#define IEEE80211_VHT_MAX_NSTS_TOTAL_SHIFT 13 +#define IEEE80211_VHT_MAX_NSTS_TOTAL_MASK (7 << IEEE80211_VHT_MAX_NSTS_TOTAL_SHIFT) + +/* for tx_highest */ +#define IEEE80211_VHT_EXT_NSS_BW_CAPABLE (1 << 13) + /** * enum ieee80211_vht_mcs_support - VHT MCS support definitions * @IEEE80211_VHT_MCS_SUPPORT_0_7: MCSes 0-7 are supported for the @@ -1547,6 +1557,7 @@ struct ieee80211_vht_operation { #define IEEE80211_VHT_CAP_SUPP_CHAN_WIDTH_160MHZ 0x00000004 #define IEEE80211_VHT_CAP_SUPP_CHAN_WIDTH_160_80PLUS80MHZ 0x00000008 #define IEEE80211_VHT_CAP_SUPP_CHAN_WIDTH_MASK 0x0000000C +#define IEEE80211_VHT_CAP_SUPP_CHAN_WIDTH_SHIFT 2 #define IEEE80211_VHT_CAP_RXLDPC 0x00000010 #define IEEE80211_VHT_CAP_SHORT_GI_80 0x00000020 #define IEEE80211_VHT_CAP_SHORT_GI_160 0x00000040 @@ -1575,6 +1586,96 @@ struct ieee80211_vht_operation { #define IEEE80211_VHT_CAP_VHT_LINK_ADAPTATION_VHT_MRQ_MFB 0x0c000000 #define IEEE80211_VHT_CAP_RX_ANTENNA_PATTERN 0x10000000 #define IEEE80211_VHT_CAP_TX_ANTENNA_PATTERN 0x20000000 +#define IEEE80211_VHT_CAP_EXT_NSS_BW_SHIFT 30 +#define IEEE80211_VHT_CAP_EXT_NSS_BW_MASK 0xc0000000 + +static int __maybe_unused +ieee80211_get_vht_max_nss(struct ieee80211_vht_cap *cap, + enum ieee80211_vht_chanwidth bw, + int mcs) +{ + u16 map = le16_to_cpu(cap->supp_mcs.rx_mcs_map); + int max_vht_nss; + int ext_nss_bw; + int supp_width; + int i, mcs_encoding; + + if (map == 0xffff) + return 0; + + if (WARN_ON(mcs > 9)) + return 0; + if (mcs <= 7) + mcs_encoding = 0; + else if (mcs == 8) + mcs_encoding = 1; + else + mcs_encoding = 2; + + /* find max_vht_nss for the given MCS */ + for (i = 7; i >= 0; i--) { + int supp = (map >> (2*i)) & 3; + + if (supp == 3) + continue; + + if (supp >= mcs_encoding) { + max_vht_nss = i; + break; + } + } + + if (!(cap->supp_mcs.tx_mcs_map & cpu_to_le16(IEEE80211_VHT_EXT_NSS_BW_CAPABLE))) + return max_vht_nss; + + ext_nss_bw = (le32_to_cpu(cap->vht_cap_info) & + IEEE80211_VHT_CAP_EXT_NSS_BW_MASK) + >> IEEE80211_VHT_CAP_EXT_NSS_BW_SHIFT; + supp_width = (le32_to_cpu(cap->vht_cap_info) & + IEEE80211_VHT_CAP_SUPP_CHAN_WIDTH_MASK) + >> IEEE80211_VHT_CAP_SUPP_CHAN_WIDTH_SHIFT; + + /* + * Cover all the special cases according to IEEE 802.11-2016 Table 9-250. + * All other cases are either factor of 1 or not valid/supported. + */ + switch (bw) { + case IEEE80211_VHT_CHANWIDTH_USE_HT: + case IEEE80211_VHT_CHANWIDTH_80MHZ: + if ((supp_width == 1 || supp_width == 2) && + ext_nss_bw == 3) + return 2 * max_vht_nss; + break; + case IEEE80211_VHT_CHANWIDTH_160MHZ: + if (supp_width == 0 && + (ext_nss_bw == 1 || ext_nss_bw == 2)) + return DIV_ROUND_UP(max_vht_nss, 2); + if (supp_width == 0 && + ext_nss_bw == 3) + return DIV_ROUND_UP(3 * max_vht_nss, 4); + if (supp_width == 1 && + ext_nss_bw == 3) + return 2 * max_vht_nss; + break; + case IEEE80211_VHT_CHANWIDTH_80P80MHZ: + if (supp_width == 0 && + ext_nss_bw == 2) + return DIV_ROUND_UP(max_vht_nss, 2); + if (supp_width == 0 && + ext_nss_bw == 3) + return DIV_ROUND_UP(3 * max_vht_nss, 4); + if (supp_width == 1 && + ext_nss_bw == 1) + return DIV_ROUND_UP(max_vht_nss, 2); + if (supp_width == 1 && + ext_nss_bw == 2) + return DIV_ROUND_UP(3 * max_vht_nss, 4); + break; + } + + /* not covered or invalid combination received */ + return max_vht_nss; +} /* Authentication algorithms */ #define WLAN_AUTH_OPEN 0 -- 2.9.3
