On Wed, Jun 29, 2016 at 1:52 PM, Krishna Chaitanya
[off-list ref] wrote:

On Wed, Jun 29, 2016 at 1:50 PM, Krishna Chaitanya
[off-list ref] wrote:

quoted

On Wed, Jun 29, 2016 at 1:41 PM, Karl Beldan [off-list ref] wrote:

quoted

On Mon, Jun 27, 2016 at 9:53 AM, Chaitanya TK [off-list ref]
wrote:

quoted

From: Chaitanya T K <redacted>

If peer support reception of STBC and LDPC, enable them for better
performance.

Signed-off-by: Chaitanya TK <redacted>
---
 include/linux/ieee80211.h          |    1 +
 net/mac80211/rc80211_minstrel_ht.c |   25 +++++++++++++++++--------
 2 files changed, 18 insertions(+), 8 deletions(-)

diff --git a/include/linux/ieee80211.h b/include/linux/ieee80211.h
index b118744..4d01130 100644
--- a/include/linux/ieee80211.h
+++ b/include/linux/ieee80211.h

@@ -1550,6 +1550,7 @@ struct ieee80211_vht_operation {
 #define IEEE80211_VHT_CAP_RXSTBC_3                             0x00000300
 #define IEEE80211_VHT_CAP_RXSTBC_4                             0x00000400
 #define IEEE80211_VHT_CAP_RXSTBC_MASK                          0x00000700
+#define IEEE80211_VHT_CAP_RXSTBC_SHIFT                         8
 #define IEEE80211_VHT_CAP_SU_BEAMFORMER_CAPABLE

0x00000800
 #define IEEE80211_VHT_CAP_SU_BEAMFORMEE_CAPABLE
0x00001000
 #define IEEE80211_VHT_CAP_BEAMFORMEE_STS_SHIFT                  13

diff --git a/net/mac80211/rc80211_minstrel_ht.c

b/net/mac80211/rc80211_minstrel_ht.c
index 30fbabf..e2fcdea 100644

--- a/net/mac80211/rc80211_minstrel_ht.c
+++ b/net/mac80211/rc80211_minstrel_ht.c

@@ -1166,13 +1166,14 @@ minstrel_ht_update_caps(void *priv, struct

ieee80211_supported_band *sband,
        struct minstrel_ht_sta_priv *msp = priv_sta;
        struct minstrel_ht_sta *mi = &msp->ht;
        struct ieee80211_mcs_info *mcs = &sta->ht_cap.mcs;
-       u16 sta_cap = sta->ht_cap.cap;
+       u16 ht_cap = sta->ht_cap.cap;
        struct ieee80211_sta_vht_cap *vht_cap = &sta->vht_cap;
        int use_vht;
        int n_supported = 0;
        int ack_dur;
        int stbc;
        int i;
+       bool ldpc;

        /* fall back to the old minstrel for legacy stations */
        if (!sta->ht_cap.ht_supported)

@@ -1210,16 +1211,24 @@ minstrel_ht_update_caps(void *priv, struct

ieee80211_supported_band *sband,
        }
        mi->sample_tries = 4;

-       /* TODO tx_flags for vht - ATM the RC API is not fine-grained
enough */
        if (!use_vht) {
-               stbc = (sta_cap & IEEE80211_HT_CAP_RX_STBC) >>
+               stbc = (ht_cap & IEEE80211_HT_CAP_RX_STBC) >>
                        IEEE80211_HT_CAP_RX_STBC_SHIFT;
-               mi->tx_flags |= stbc << IEEE80211_TX_CTL_STBC_SHIFT;

-               if (sta_cap & IEEE80211_HT_CAP_LDPC_CODING)
-                       mi->tx_flags |= IEEE80211_TX_CTL_LDPC;
+               if (ht_cap & IEEE80211_HT_CAP_LDPC_CODING)
+                       ldpc = true;
+       } else {
+               stbc = (vht_cap->cap & IEEE80211_VHT_CAP_RXSTBC_MASK) >>
+                       IEEE80211_VHT_CAP_RXSTBC_SHIFT;
+
+               if (vht_cap->cap & IEEE80211_VHT_CAP_RXLDPC)
+                       ldpc = true;
        }

+       mi->tx_flags |= stbc << IEEE80211_TX_CTL_STBC_SHIFT;
+       if (ldpc)
+               mi->tx_flags |= IEEE80211_TX_CTL_LDPC;
+

Here you are using ldpc uninitialized.

yeah, will fix it.

Johannes,

How do you want to proceed? Do you want to
revert this patch and shall i send another patch?