<def f='src/src/sys/dev/pci/if_iwmreg.h' l='4304' ll='4308' type='__uint32_t iwm_mvm_get_scd_ssn(struct iwm_mvm_tx_resp * tx_resp)'/>
<doc f='src/src/sys/dev/pci/if_iwmreg.h' l='4291'>/**
 * iwm_mvm_get_scd_ssn - returns the SSN of the SCD
 * @tx_resp: the Tx response from the fw (agg or non-agg)
 *
 * When the fw sends an AMPDU, it fetches the MPDUs one after the other. Since
 * it can&apos;t know that everything will go well until the end of the AMPDU, it
 * can&apos;t know in advance the number of MPDUs that will be sent in the current
 * batch. This is why it writes the agg Tx response while it fetches the MPDUs.
 * Hence, it can&apos;t know in advance what the SSN of the SCD will be at the end
 * of the batch. This is why the SSN of the SCD is written at the end of the
 * whole struct at a variable offset. This function knows how to cope with the
 * variable offset and returns the SSN of the SCD.
 */</doc>
