iwlwifi: add iwl_tlv_array_len()

Allows to easily calculate array length at the end of a TLV.

Signed-off-by: Shahar S Matityahu <shahar.s.matityahu@intel.com>
Signed-off-by: Luca Coelho <luciano.coelho@intel.com>

diff --git a/drivers/net/wireless/intel/iwlwifi/fw/file.h b/drivers/net/wireless/intel/iwlwifi/fw/file.h
index 329b00e..1bdcab9 100644 (file)
--- a/drivers/net/wireless/intel/iwlwifi/fw/file.h
+++ b/drivers/net/wireless/intel/iwlwifi/fw/file.h
@@ -972,4 +972,19 @@ struct iwl_fw_cmd_version {
        u8 notif_ver;
 } __packed;
 
+static inline size_t _iwl_tlv_array_len(const struct iwl_ucode_tlv *tlv,
+                                       size_t fixed_size, size_t var_size)
+{
+       size_t var_len = le32_to_cpu(tlv->length) - fixed_size;
+
+       if (WARN_ON(var_len % var_size))
+               return 0;
+
+       return var_len / var_size;
+}
+
+#define iwl_tlv_array_len(_tlv_ptr, _struct_ptr, _memb)                        \
+       _iwl_tlv_array_len((_tlv_ptr), sizeof(*(_struct_ptr)),          \
+                          sizeof(_struct_ptr->_memb[0]))
+
 #endif  /* __iwl_fw_file_h__ */