nfc: port100: fix using -ERRNO as command type mask

commit 2195f2062e4cc93870da8e71c318ef98a1c51cef upstream.

During probing, the driver tries to get a list (mask) of supported
command types in port100_get_command_type_mask() function.  The value
is u64 and 0 is treated as invalid mask (no commands supported).  The
function however returns also -ERRNO as u64 which will be interpret as
valid command mask.

Return 0 on every error case of port100_get_command_type_mask(), so the
probing will stop.

Cc: <stable@vger.kernel.org>
Fixes: 2d2c10ed4976 ("NFC: port100: Commands mechanism implementation")
Signed-off-by: Krzysztof Kozlowski <krzysztof.kozlowski@canonical.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

diff --git a/drivers/nfc/port100.c b/drivers/nfc/port100.c
index 8e4d355dc3aec4e6c0e75afe01f2e9b190009f68..1caebefb25ff1d43abe9adf71e933fe2732ad497 100644 (file)
--- a/drivers/nfc/port100.c
+++ b/drivers/nfc/port100.c
@@ -1003,11 +1003,11 @@ static u64 port100_get_command_type_mask(struct port100 *dev)
 
        skb = port100_alloc_skb(dev, 0);
        if (!skb)
-               return -ENOMEM;
+               return 0;
 
        resp = port100_send_cmd_sync(dev, PORT100_CMD_GET_COMMAND_TYPE, skb);
        if (IS_ERR(resp))
-               return PTR_ERR(resp);
+               return 0;
 
        if (resp->len < 8)
                mask = 0;