[PATCH] wpa_supplicant: Allow disabling LDPC

[Pawel Kulakowski]

Allows user to disable LDPC coding.
This possibility is useful for testing purpose.

Signed-off-by: Pawel Kulakowski <pawel.kulakowski at tieto.com>
---
 Kernel patch sent to linux-wireless mailing list
 wpa_supplicant/config.c            |    2 ++
 wpa_supplicant/config_ssid.h       |    9 +++++++++
 wpa_supplicant/wpa_supplicant.c    |   22 ++++++++++++++++++++++
 wpa_supplicant/wpa_supplicant.conf |    4 ++++
 4 files changed, 37 insertions(+)

diff --git a/wpa_supplicant/config.c b/wpa_supplicant/config.c
index 23aab4b..6a46210 100644
--- a/wpa_supplicant/config.c
+++ b/wpa_supplicant/config.c
@@ -1701,6 +1701,7 @@ static const struct parse_data ssid_fields[] = {
 	{ INT_RANGE(disable_ht, 0, 1) },
 	{ INT_RANGE(disable_ht40, -1, 1) },
 	{ INT_RANGE(disable_sgi, 0, 1) },
+	{ INT_RANGE(disable_ldpc, 0, 1) },
 	{ INT_RANGE(disable_max_amsdu, -1, 1) },
 	{ INT_RANGE(ampdu_factor, -1, 3) },
 	{ INT_RANGE(ampdu_density, -1, 7) },
@@ -2157,6 +2158,7 @@ void wpa_config_set_network_defaults(struct wpa_ssid *ssid)
 	ssid->disable_ht = DEFAULT_DISABLE_HT;
 	ssid->disable_ht40 = DEFAULT_DISABLE_HT40;
 	ssid->disable_sgi = DEFAULT_DISABLE_SGI;
+	ssid->disable_ldpc = DEFAULT_DISABLE_LDPC;
 	ssid->disable_max_amsdu = DEFAULT_DISABLE_MAX_AMSDU;
 	ssid->ampdu_factor = DEFAULT_AMPDU_FACTOR;
 	ssid->ampdu_density = DEFAULT_AMPDU_DENSITY;
diff --git a/wpa_supplicant/config_ssid.h b/wpa_supplicant/config_ssid.h
index d515030..71829ef 100644
--- a/wpa_supplicant/config_ssid.h
+++ b/wpa_supplicant/config_ssid.h
@@ -30,6 +30,7 @@
 #define DEFAULT_DISABLE_HT 0
 #define DEFAULT_DISABLE_HT40 0
 #define DEFAULT_DISABLE_SGI 0
+#define DEFAULT_DISABLE_LDPC 0
 #define DEFAULT_DISABLE_MAX_AMSDU -1 /* no change */
 #define DEFAULT_AMPDU_FACTOR -1 /* no change */
 #define DEFAULT_AMPDU_DENSITY -1 /* no change */
@@ -525,6 +526,14 @@ struct wpa_ssid {
 	int disable_sgi;
 
 	/**
+	 * disable_ldpc - Disable LDPC for this network
+	 *
+	 * By default, use it if it is available, but this can be configured
+	 * to 1 to have it disabled.
+	 */
+	int disable_ldpc;
+
+	/**
 	 * disable_max_amsdu - Disable MAX A-MSDU
 	 *
 	 * A-MDSU will be 3839 bytes when disabled, or 7935
diff --git a/wpa_supplicant/wpa_supplicant.c b/wpa_supplicant/wpa_supplicant.c
index b47e423..5c6f625 100644
--- a/wpa_supplicant/wpa_supplicant.c
+++ b/wpa_supplicant/wpa_supplicant.c
@@ -2922,6 +2922,27 @@ static int wpa_set_disable_sgi(struct wpa_supplicant *wpa_s,
 }
 
 
+static int wpa_set_disable_ldpc(struct wpa_supplicant *wpa_s,
+			       struct ieee80211_ht_capabilities *htcaps,
+			       struct ieee80211_ht_capabilities *htcaps_mask,
+			       int disabled)
+{
+	/* Masking these out disables LDPC */
+	u16 msk = host_to_le16(HT_CAP_INFO_LDPC_CODING_CAP);
+
+	wpa_msg(wpa_s, MSG_DEBUG, "set_disable_ldpc: %d", disabled);
+
+	if (disabled)
+		htcaps->ht_capabilities_info &= ~msk;
+	else
+		htcaps->ht_capabilities_info |= msk;
+
+	htcaps_mask->ht_capabilities_info |= msk;
+
+	return 0;
+}
+
+
 void wpa_supplicant_apply_ht_overrides(
 	struct wpa_supplicant *wpa_s, struct wpa_ssid *ssid,
 	struct wpa_driver_associate_params *params)
@@ -2945,6 +2966,7 @@ void wpa_supplicant_apply_ht_overrides(
 	wpa_set_ampdu_density(wpa_s, htcaps, htcaps_mask, ssid->ampdu_density);
 	wpa_set_disable_ht40(wpa_s, htcaps, htcaps_mask, ssid->disable_ht40);
 	wpa_set_disable_sgi(wpa_s, htcaps, htcaps_mask, ssid->disable_sgi);
+	wpa_set_disable_ldpc(wpa_s, htcaps, htcaps_mask, ssid->disable_ldpc);
 }
 
 #endif /* CONFIG_HT_OVERRIDES */
diff --git a/wpa_supplicant/wpa_supplicant.conf b/wpa_supplicant/wpa_supplicant.conf
index 03c6f5f..3358250 100644
--- a/wpa_supplicant/wpa_supplicant.conf
+++ b/wpa_supplicant/wpa_supplicant.conf
@@ -947,6 +947,10 @@ fast_reauth=1
 # 0 = SGI enabled (if AP supports it)
 # 1 = SGI disabled
 #
+# disable_ldpc: Whether LDPC should be disabled.
+# 0 = LDPC enabled (if AP supports it)
+# 1 = LDPC disabled
+#
 # ht_mcs:  Configure allowed MCS rates.
 #  Parsed as an array of bytes, in base-16 (ascii-hex)
 # ht_mcs=""                                   // Use all available (default)
-- 
1.7.9.5