brcmfmac: fallback to mimo_bw_cap for older firmwares

In order to support the driver behaviour introduced by:

   commit d0575a5a703978c43e25128421158c78534ba100
   Author: Daniel Kim <dekim@broadcom.com>
   Date:   Wed Mar 12 18:12:14 2014 -0700

       brcmfmac: Enable 40MHz bandwidth in 2GHz band and OBSS scanning

in devices that do not support bwcap firmware command a fallback
is added.

Reviewed-by: Daniel (Deognyoun) Kim <dekim@broadcom.com>
Reviewed-by: Pieter-Paul Giesberts <pieterpg@broadcom.com>
Signed-off-by: Arend van Spriel <arend@broadcom.com>
Signed-off-by: John W. Linville <linville@tuxdriver.com>

1 files changed, 18 insertions, 8 deletions

diff --git a/drivers/net/wireless/brcm80211/brcmfmac/wl_cfg80211.c b/drivers/net/wireless/brcm80211/brcmfmac/wl_cfg80211.c
index 428b4cb94da1..e0e649aab8db 100644
--- a/drivers/net/wireless/brcm80211/brcmfmac/wl_cfg80211.c
+++ b/drivers/net/wireless/brcm80211/brcmfmac/wl_cfg80211.c
@@ -4930,16 +4930,27 @@ static void init_vif_event(struct brcmf_cfg80211_vif_event *event)
         mutex_init(&event->vif_event_lock);
 }
 
-static int brcmf_set_bwcap(struct brcmf_if *ifp, u32 band, u32 bw_cap)
+static int brcmf_enable_bw40_2g(struct brcmf_if *ifp)
 {
         struct brcmf_fil_bwcap_le band_bwcap;
+        u32 val;
         int err;
 
-        band_bwcap.band = cpu_to_le32(band);
-        band_bwcap.bw_cap = cpu_to_le32(bw_cap);
-        err = brcmf_fil_iovar_data_set(ifp, "bw_cap", &band_bwcap,
-                                       sizeof(band_bwcap));
+        /* verify support for bw_cap command */
+        val = WLC_BAND_5G;
+        err = brcmf_fil_iovar_int_get(ifp, "bw_cap", &val);
 
+        if (!err) {
+                /* only set 2G bandwidth using bw_cap command */
+                band_bwcap.band = cpu_to_le32(WLC_BAND_2G);
+                band_bwcap.bw_cap = cpu_to_le32(WLC_BW_40MHZ_BIT);
+                err = brcmf_fil_iovar_data_set(ifp, "bw_cap", &band_bwcap,
+                                               sizeof(band_bwcap));
+        } else {
+                brcmf_dbg(INFO, "fallback to mimo_bw_cap\n");
+                val = WLC_N_BW_40ALL;
+                err = brcmf_fil_iovar_int_set(ifp, "mimo_bw_cap", val);
+        }
         return err;
 }
 
@@ -5005,11 +5016,10 @@ struct brcmf_cfg80211_info *brcmf_cfg80211_attach(struct brcmf_pub *drvr,
          */
         if (wiphy->bands[IEEE80211_BAND_2GHZ]->ht_cap.cap &
             IEEE80211_HT_CAP_SUP_WIDTH_20_40) {
-                err = brcmf_set_bwcap(ifp, WLC_BAND_2G, WLC_BW_CAP_40MHZ);
-                if (!err) {
+                err = brcmf_enable_bw40_2g(ifp);
+                if (!err)
                         err = brcmf_fil_iovar_int_set(ifp, "obss_coex",
                                                       BRCMF_OBSS_COEX_AUTO);
-                }
         }
 
         err = brcmf_fil_iovar_int_set(ifp, "tdls_enable", 1);