RE: [PATCH v3 19/28] scsi: hpsa: use generic power management

[Don.Brace]

-----Original Message-----
From: Vaibhav Gupta [mailto:vaibhavgupta40@xxxxxxxxx] 
Sent: Thursday, October 1, 2020 7:25 AM
To: Bjorn Helgaas <helgaas@xxxxxxxxxx>; Bjorn Helgaas <bhelgaas@xxxxxxxxxx>; Bjorn Helgaas <bjorn@xxxxxxxxxxx>; Vaibhav Gupta <vaibhav.varodek@xxxxxxxxx>; Adam Radford <aradford@xxxxxxxxx>; James E.J. Bottomley <jejb@xxxxxxxxxxxxx>; Martin K. Petersen <martin.petersen@xxxxxxxxxx>; Adaptec OEM Raid Solutions <aacraid@xxxxxxxxxxxxx>; Hannes Reinecke <hare@xxxxxxxx>; Bradley Grove <linuxdrivers@xxxxxxxxxxxx>; John Garry <john.garry@xxxxxxxxxx>; Don Brace <don.brace@xxxxxxxxxxxxx>; James Smart <james.smart@xxxxxxxxxxxx>; Dick Kennedy <dick.kennedy@xxxxxxxxxxxx>; Kashyap Desai <kashyap.desai@xxxxxxxxxxxx>; Sumit Saxena <sumit.saxena@xxxxxxxxxxxx>; Shivasharan S <shivasharan.srikanteshwara@xxxxxxxxxxxx>; Sathya Prakash <sathya.prakash@xxxxxxxxxxxx>; Sreekanth Reddy <sreekanth.reddy@xxxxxxxxxxxx>; Suganath Prabu Subramani <suganath-prabu.subramani@xxxxxxxxxxxx>; Jack Wang <jinpu.wang@xxxxxxxxxxxxxxx>
Cc: Vaibhav Gupta <vaibhavgupta40@xxxxxxxxx>; Shuah Khan <skhan@xxxxxxxxxxxxxxxxxxx>; linux-kernel@xxxxxxxxxxxxxxx; linux-kernel-mentees@xxxxxxxxxxxxxxxxxxxxxxxxx; linux-scsi@xxxxxxxxxxxxxxx; esc.storagedev@xxxxxxxxxxxxx; megaraidlinux.pdl@xxxxxxxxxxxx; MPT-FusionLinux.pdl@xxxxxxxxxxxx
Subject: [PATCH v3 19/28] scsi: hpsa: use generic power management

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Drivers should do only device-specific jobs. But in general, drivers using legacy PCI PM framework for .suspend()/.resume() have to manage many PCI PM-related tasks themselves which can be done by PCI Core itself. This brings extra load on the driver and it directly calls PCI helper functions to handle them.

Switch to the new generic framework by updating function signatures and define a "struct dev_pm_ops" variable to bind PM callbacks. Also, remove unnecessary calls to the PCI Helper functions along with the legacy .suspend & .resume bindings.

Signed-off-by: Vaibhav Gupta <vaibhavgupta40@xxxxxxxxx>

Acked-by: Don Brace <don.brace@xxxxxxxxxxxxx>

---
 drivers/scsi/hpsa.c | 12 +++++++-----
 1 file changed, 7 insertions(+), 5 deletions(-)

diff --git a/drivers/scsi/hpsa.c b/drivers/scsi/hpsa.c index 81d0414e2117..70bdd6fe91ee 100644
--- a/drivers/scsi/hpsa.c
+++ b/drivers/scsi/hpsa.c
@@ -9070,25 +9070,27 @@ static void hpsa_remove_one(struct pci_dev *pdev)
        hpda_free_ctlr_info(h);                         /* init_one 1 */
 }

-static int hpsa_suspend(__attribute__((unused)) struct pci_dev *pdev,
-       __attribute__((unused)) pm_message_t state)
+static int __maybe_unused hpsa_suspend(
+       __attribute__((unused)) struct device *dev)
 {
        return -ENOSYS;
 }

-static int hpsa_resume(__attribute__((unused)) struct pci_dev *pdev)
+static int __maybe_unused hpsa_resume
+       (__attribute__((unused)) struct device *dev)
 {
        return -ENOSYS;
 }

+static SIMPLE_DEV_PM_OPS(hpsa_pm_ops, hpsa_suspend, hpsa_resume);
+
 static struct pci_driver hpsa_pci_driver = {
        .name = HPSA,
        .probe = hpsa_init_one,
        .remove = hpsa_remove_one,
        .id_table = hpsa_pci_device_id, /* id_table */
        .shutdown = hpsa_shutdown,
-       .suspend = hpsa_suspend,
-       .resume = hpsa_resume,
+       .driver.pm = &hpsa_pm_ops,
 };

 /* Fill in bucket_map[], given nsgs (the max number of
--
2.28.0