[PATCH v3 08/23] ata: libata-core: Do not register PM operations for SAS ports

Damien Le Moal
2023-09-15T08:24:56Z

libsas does its own domain based power management of ports. For such
ports, libata should not use a device type defining power management
operations as executing these operations for suspend/resume in addition
to libsas calls to ata_sas_port_suspend() and ata_sas_port_resume() is
not necessary (and likely dangerous to do, even though problems are not
seen currently).

Introduce the new ata_port_sas_type device_type for ports managed by
libsas. This new device type is used in ata_tport_add() and is defined
without power management operations.

Fixes: 2fcbdcb4c802 ("[SCSI] libata: export ata_port suspend/resume infrastructure for sas")
Cc: stable@vger.kernel.org
Signed-off-by: Damien Le Moal <dlemoal@kernel.org>
Reviewed-by: Hannes Reinecke <hare@suse.de>
Tested-by: Chia-Lin Kao (AceLan) <acelan.kao@canonical.com>
---
drivers/ata/libata-core.c | 2 +-
drivers/ata/libata-transport.c | 9 ++++++++-
drivers/ata/libata.h | 2 ++
3 files changed, 11 insertions(+), 2 deletions(-)

diff --git a/drivers/ata/libata-core.c b/drivers/ata/libata-core.c
index 0479493e54bd..18b2a0da9e54 100644
--- a/drivers/ata/libata-core.c
+++ b/drivers/ata/libata-core.c
@@ -5339,7 +5339,7 @@ EXPORT_SYMBOL_GPL(ata_host_resume);
#endif

const struct device_type ata_port_type = {
- .name = "ata_port",
+ .name = ATA_PORT_TYPE_NAME,
#ifdef CONFIG_PM
.pm = &ata_port_pm_ops,
#endif
diff --git a/drivers/ata/libata-transport.c b/drivers/ata/libata-transport.c
index e4fb9d1b9b39..3e49a877500e 100644
--- a/drivers/ata/libata-transport.c
+++ b/drivers/ata/libata-transport.c
@@ -266,6 +266,10 @@ void ata_tport_delete(struct ata_port *ap)
put_device(dev);
}

+static const struct device_type ata_port_sas_type = {
+ .name = ATA_PORT_TYPE_NAME,
+};
+
/** ata_tport_add - initialize a transport ATA port structure
*
* @parent: parent device
@@ -283,7 +287,10 @@ int ata_tport_add(struct device *parent,
struct device *dev = &ap->tdev;

device_initialize(dev);
- dev->type = &ata_port_type;
+ if (ap->flags & ATA_FLAG_SAS_HOST)
+ dev->type = &ata_port_sas_type;
+ else
+ dev->type = &ata_port_type;

dev->parent = parent;
ata_host_get(ap->host);
diff --git a/drivers/ata/libata.h b/drivers/ata/libata.h
index a5ee06f0234a..c57e094c3af9 100644
--- a/drivers/ata/libata.h
+++ b/drivers/ata/libata.h
@@ -30,6 +30,8 @@ enum {
ATA_DNXFER_QUIET = (1 << 31),
};

+#define ATA_PORT_TYPE_NAME "ata_port"
+
extern atomic_t ata_print_id;
extern int atapi_passthru16;
extern int libata_fua;
--
2.41.0