brcmfmac: Add module parameter to disable features.

For debugging purpose it is very handy to be able to disable
features. It has happened a few times that new features turned
out not always being properly detected for all devices/firmwares.
Making it possible to disable the feature with a module parameter
will make testing/debugging easier.
Reviewed-by: Arend Van Spriel <arend@broadcom.com>
Reviewed-by: Franky (Zhenhui) Lin <frankyl@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>

drivers/net/wireless/brcm80211/brcmfmac/feature.c

@@ -15,6 +15,7 @@
  */
 
 #include <linux/netdevice.h>
+#include <linux/module.h>
 
 #include <brcm_hw_ids.h>
 #include "core.h"
@@ -23,6 +24,12 @@
 #include "fwil.h"
 #include "feature.h"
 
+
+/* Module param feature_disable (global for all devices) */
+static int brcmf_feature_disable;
+module_param_named(feature_disable, brcmf_feature_disable, int, 0);
+MODULE_PARM_DESC(feature_disable, "Disable features");
+
 /*
  * expand feature list to array of feature strings.
  */
@@ -131,6 +138,12 @@ void brcmf_feat_attach(struct brcmf_pub *drvr)
 		brcmf_feat_iovar_int_set(ifp, BRCMF_FEAT_MBSS, "mbss", 0);
 	brcmf_feat_iovar_int_get(ifp, BRCMF_FEAT_P2P, "p2p");
 
+	if (brcmf_feature_disable) {
+		brcmf_dbg(INFO, "Features: 0x%02x, disable: 0x%02x\n",
+			  ifp->drvr->feat_flags, brcmf_feature_disable);
+		ifp->drvr->feat_flags &= ~brcmf_feature_disable;
+	}
+
 	/* set chip related quirks */
 	switch (drvr->bus_if->chip) {
 	case BRCM_CC_43236_CHIP_ID: