brcmfmac: Workaround in change vif for wpa_supplicant support.

Different wpa_supplicants have different behavior and expectations
regarding the change_virtual_intf behavior. This patch implements
a workaround for the different versions and possible brcmfmac
configuration.

Reviewed-by: Arend Van Spriel <arend@broadcom.com>
Reviewed-by: Pieter-Paul Giesberts <pieterpg@broadcom.com>
Signed-off-by: Hante Meuleman <meuleman@broadcom.com>
Signed-off-by: Arend van Spriel <arend@broadcom.com>
Signed-off-by: Kalle Valo <kvalo@codeaurora.org>

diff --git a/drivers/net/wireless/brcm80211/brcmfmac/cfg80211.c b/drivers/net/wireless/brcm80211/brcmfmac/cfg80211.c
index 3e1c8fcf57cb250979ccf335f8f5115b3f4a2a60..891f4ed8c5e381d52ddf89438e95c763bc6087ae 100644 (file)
--- a/drivers/net/wireless/brcm80211/brcmfmac/cfg80211.c
+++ b/drivers/net/wireless/brcm80211/brcmfmac/cfg80211.c
@@ -777,6 +777,37 @@ brcmf_cfg80211_change_iface(struct wiphy *wiphy, struct net_device *ndev,
        s32 err = 0;
 
        brcmf_dbg(TRACE, "Enter, idx=%d, type=%d\n", ifp->bssidx, type);
+
+       /* WAR: There are a number of p2p interface related problems which
+        * need to be handled initially (before doing the validate).
+        * wpa_supplicant tends to do iface changes on p2p device/client/go
+        * which are not always possible/allowed. However we need to return
+        * OK otherwise the wpa_supplicant wont start. The situation differs
+        * on configuration and setup (p2pon=1 module param). The first check
+        * is to see if the request is a change to station for p2p iface.
+        */
+       if ((type == NL80211_IFTYPE_STATION) &&
+           ((vif->wdev.iftype == NL80211_IFTYPE_P2P_CLIENT) ||
+            (vif->wdev.iftype == NL80211_IFTYPE_P2P_GO) ||
+            (vif->wdev.iftype == NL80211_IFTYPE_P2P_DEVICE))) {
+               brcmf_dbg(TRACE, "Ignoring cmd for p2p if\n");
+               /* Now depending on whether module param p2pon=1 was used the
+                * response needs to be either 0 or EOPNOTSUPP. The reason is
+                * that if p2pon=1 is used, but a newer supplicant is used then
+                * we should return an error, as this combination wont work.
+                * In other situations 0 is returned and supplicant will start
+                * normally. It will give a trace in cfg80211, but it is the
+                * only way to get it working. Unfortunately this will result
+                * in situation where we wont support new supplicant in
+                * combination with module param p2pon=1, but that is the way
+                * it is. If the user tries this then unloading of driver might
+                * fail/lock.
+                */
+               if (cfg->p2p.p2pdev_dynamically)
+                       return -EOPNOTSUPP;
+               else
+                       return 0;
+       }
        err = brcmf_vif_change_validate(wiphy_to_cfg(wiphy), vif, type);
        if (err) {
                brcmf_err("iface validation failed: err=%d\n", err);
@@ -792,18 +823,6 @@ brcmf_cfg80211_change_iface(struct wiphy *wiphy, struct net_device *ndev,
                infra = 0;
                break;
        case NL80211_IFTYPE_STATION:
-               /* Ignore change for p2p IF. Unclear why supplicant does this */
-               if ((vif->wdev.iftype == NL80211_IFTYPE_P2P_CLIENT) ||
-                   (vif->wdev.iftype == NL80211_IFTYPE_P2P_GO)) {
-                       brcmf_dbg(TRACE, "Ignoring cmd for p2p if\n");
-                       /* WAR: It is unexpected to get a change of VIF for P2P
-                        * IF, but it happens. The request can not be handled
-                        * but returning EPERM causes a crash. Returning 0
-                        * without setting ieee80211_ptr->iftype causes trace
-                        * (WARN_ON) but it works with wpa_supplicant
-                        */
-                       return 0;
-               }
                infra = 1;
                break;
        case NL80211_IFTYPE_AP: