NCR5380_select(9)

💅 NCR5380_select(9) — a Kernel API Manual moment ✨

okay so bestie, welcome to the Kernel API Manual page for NCR5380_select 🎀 this is the group chat where we explain how to get a SCSI command its very own nexus. stay with me, it's giving iconic 💖

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✨ NAME ✨

NCR5380_select — attempt arbitration and selection for a given command 🦋

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🌸 SYNOPSIS 🌸

bool NCR5380_select (struct Scsi_Host *instance , struct scsi_cmnd *cmd
);

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🫶 ARGUMENTS 🫶

• instance — the Scsi_Host instance, aka the host that's doing all this 💜
• cmd — the scsi_cmnd to execute, the little errand we're running 🏃‍♀️

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🔥 DESCRIPTION 🔥

so this routine establishes an I_T_L nexus for a SCSI command — that's the whole main character energy of the function. and to do that it goes through ARBITRATION, SELECTION and MESSAGE OUT phases, plus an IDENTIFY message. it's a whole production, no cap 💅

as for what it gives back:

• returns true if the operation should be retried (try again bestie 🙈)
• returns false if it should not be retried (not this time 💀)

Side effects, because yes there are always side effects:

• if the bus is busy, or arbitration failed, or whatever other drama happened, NCR5380_select will exit with the registers exactly as they should have been on entry — ie. SELECT_ENABLE will be set appropriately, and the NCR5380 will cease to drive any SCSI bus signals ⭐
• if it's successful: the I_T_L nexus gets established, and hostdata->connected will be set to cmd. the SELECT interrupt will be disabled 🎀
• if it fails (no target): scsi_done will be called, and the cmd->result host byte set to DID_BAD_TARGET 😭

fr fr, keep that nexus-or-nothing energy in mind — the success and failure exits do very different things, and the "no target" path is the one doing the scsi_done call and setting DID_BAD_TARGET. 💀

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👑 SEE ALSO 👑

Kernel file ./drivers/scsi/NCR5380.c and its entire friend group, all invited to the group chat:

• initialize_SCp(9)
• NCR5380_poll_politely2(9)
• NCR5380_print(9)
• NCR5380_print_phase(9)
• NCR5380_info(9)
• NCR5380_init(9)
• NCR5380_maybe_reset_bus(9)
• NCR5380_exit(9)
• complete_cmd(9)
• NCR5380_queue_command(9)
• dequeue_next_cmd(9)
• NCR5380_main(9)
• NCR5380_intr(9)
• NCR5380_transfer_pio(9)
• do_reset(9)
• do_abort(9)
• list_find_cmd(9)
• NCR5380_abort(9)
• NCR5380_host_reset(9)

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that's the whole page bestie, ily, go establish some nexuses 🧚💖 this one came straight out of ./drivers/scsi and it's dated October 2026 — slay, see you next manpage ✨🌈