ata: ahci: Disable DIPM if host lacks support
authorDamien Le Moal <dlemoal@kernel.org>
Tue, 1 Jul 2025 12:53:17 +0000 (21:53 +0900)
committerNiklas Cassel <cassel@kernel.org>
Wed, 2 Jul 2025 10:01:33 +0000 (12:01 +0200)
commitf7870e8d345cdabfb94bcbdcba6a07e050f8705e
treefe379aa340d807702a42b34f8d6f10eea5b9e5a0
parent413e800cadbf67550d76c77c230b2ecd96bce83a
ata: ahci: Disable DIPM if host lacks support

The AHCI specification version 1.3.1 section 8.3.1.4 (Software
Requirements and Precedence) states that:

If CAP.SSC or CAP.PSC is cleared to ‘0’, software should disable
device-initiated power management by issuing the appropriate SET
FEATURES command to the device.

To satisfy this constraint and force ata_dev_configure to disable the
device DIPM feature, modify ahci_update_initial_lpm_policy() to set the
ATA_FLAG_NO_DIPM flag on ports that have a host with either the
ATA_HOST_NO_PART flag set or the ATA_HOST_NO_SSC flag set.

Signed-off-by: Damien Le Moal <dlemoal@kernel.org>
Reviewed-by: Niklas Cassel <cassel@kernel.org>
Reviewed-by: Hannes Reinecke <hare@suse.de>
Reviewed-by: Hannes Reinecke <hare@suse.de.>
Link: https://lore.kernel.org/r/20250701125321.69496-7-dlemoal@kernel.org
Signed-off-by: Niklas Cassel <cassel@kernel.org>
drivers/ata/ahci.c