[PATCH] brcmfmac: check if we can support used firmware API version

["Rafał Miłecki" <zajec5@gmail.com>]

From: Rafał Miłecki <rafal@milecki.pl>

Every new firmware API will most likely require changes in our code to
support it. Right now we support 2 versions only. Refuse to init if we
detect newer version.

Signed-off-by: Rafał Miłecki <rafal@milecki.pl>
---
Hi Arend,

I think you were concerned about possible firmware API changes. Please
review this patch, I hope it's a proper check for running unsupported
firmware version which could result in broken communication between host
driver and a device.
---
 drivers/net/wireless/broadcom/brcm80211/brcmfmac/cfg80211.c | 5 +++++
 1 file changed, 5 insertions(+)

diff --git a/drivers/net/wireless/broadcom/brcm80211/brcmfmac/cfg80211.c b/drivers/net/wireless/broadcom/brcm80211/brcmfmac/cfg80211.c
index 0babfc7..c69ae84 100644
--- a/drivers/net/wireless/broadcom/brcm80211/brcmfmac/cfg80211.c
+++ b/drivers/net/wireless/broadcom/brcm80211/brcmfmac/cfg80211.c
@@ -6816,6 +6816,11 @@ struct brcmf_cfg80211_info *brcmf_cfg80211_attach(struct brcmf_pub *drvr,
 		brcmf_err("Failed to get D11 version (%d)\n", err);
 		goto priv_out;
 	}
+	if (io_type > BRCMU_D11AC_IOTYPE) {
+		brcmf_err("Unsupported IO version %d\n", io_type);
+		goto priv_out;
+	}
+
 	cfg->d11inf.io_type = (u8)io_type;
 	brcmu_d11_attach(&cfg->d11inf);
 
-- 
2.10.1