From: Damien Le Moal <dlemoal@kernel.org>
Date: Tue, 1 Jul 2025 12:53:16 +0000 (+0900)
Subject: ata: libata-sata: Disallow changing LPM state if not supported
X-Git-Url: https://www.infradead.org/git/?a=commitdiff_plain;h=413e800cadbf67550d76c77c230b2ecd96bce83a;p=users%2Fjedix%2Flinux-maple.git

ata: libata-sata: Disallow changing LPM state if not supported

Modify ata_scsi_lpm_store() to return an error if a user attempts to set
a link power management policy for a port that does not support LPM,
that is, ports flagged with ATA_FLAG_NO_LPM.

Signed-off-by: Damien Le Moal <dlemoal@kernel.org>
Reviewed-by: Niklas Cassel <cassel@kernel.org>
Reviewed-by: Hannes Reinecke <hare@suse.de>
Link: https://lore.kernel.org/r/20250701125321.69496-6-dlemoal@kernel.org
Signed-off-by: Niklas Cassel <cassel@kernel.org>
---

diff --git a/drivers/ata/libata-sata.c b/drivers/ata/libata-sata.c
index cb46ce276bb1..47169c469f43 100644
--- a/drivers/ata/libata-sata.c
+++ b/drivers/ata/libata-sata.c
@@ -924,6 +924,11 @@ static ssize_t ata_scsi_lpm_store(struct device *device,
 
 	spin_lock_irqsave(ap->lock, flags);
 
+	if (ap->flags & ATA_FLAG_NO_LPM) {
+		count = -EOPNOTSUPP;
+		goto out_unlock;
+	}
+
 	ata_for_each_link(link, ap, EDGE) {
 		ata_for_each_dev(dev, &ap->link, ENABLED) {
 			if (dev->quirks & ATA_QUIRK_NOLPM) {