[PATCH v3] wifi: mt76: mt7921e: add pci .shutdown() support

[Deren Wu]

From: Leon Yen <Leon.Yen at mediatek.com>

Some combinations of hosts cannnot detect mt7921e after reboot. The
interoperability issue is caused by the status mismatch between host
and chip fw. In such cases, the driver should stop chip activities
and reset chip to default state before reboot.

Suggested-by: angelogioacchino.delregno at collabora.com
Co-developed-by: Deren Wu <deren.wu at mediatek.com>
Signed-off-by: Deren Wu <deren.wu at mediatek.com>
Signed-off-by: Leon Yen <Leon.Yen at mediatek.com>
---
v3:
  - use pci .shutdown() instead of reboot notification
  - add suggested by Angelo
v2: add reboot notification block in mt76
---
 drivers/net/wireless/mediatek/mt76/mt7921/pci.c | 16 ++++++++++++++++
 1 file changed, 16 insertions(+)

diff --git a/drivers/net/wireless/mediatek/mt76/mt7921/pci.c b/drivers/net/wireless/mediatek/mt76/mt7921/pci.c
index 28342ec940f0..cb72ded37256 100644
--- a/drivers/net/wireless/mediatek/mt76/mt7921/pci.c
+++ b/drivers/net/wireless/mediatek/mt76/mt7921/pci.c
@@ -507,6 +507,21 @@ static int mt7921_pci_resume(struct device *device)
 	return err;
 }
 
+static void mt7921_pci_shutdown(struct pci_dev *pdev)
+{
+	struct mt76_dev *mdev = pci_get_drvdata(pdev);
+	struct mt7921_dev *dev = container_of(mdev, struct mt7921_dev, mt76);
+	struct mt76_connac_pm *pm = &dev->pm;
+
+	cancel_delayed_work_sync(&pm->ps_work);
+	cancel_work_sync(&pm->wake_work);
+
+	/* chip cleanup before reboot */
+	mt7921_mcu_drv_pmctrl(dev);
+	mt7921_dma_cleanup(dev);
+	mt7921_wfsys_reset(dev);
+}
+
 static DEFINE_SIMPLE_DEV_PM_OPS(mt7921_pm_ops, mt7921_pci_suspend, mt7921_pci_resume);
 
 static struct pci_driver mt7921_pci_driver = {
@@ -514,6 +529,7 @@ static struct pci_driver mt7921_pci_driver = {
 	.id_table	= mt7921_pci_device_table,
 	.probe		= mt7921_pci_probe,
 	.remove		= mt7921_pci_remove,
+	.shutdown	= mt7921_pci_shutdown,
 	.driver.pm	= pm_sleep_ptr(&mt7921_pm_ops),
 };
 
-- 
2.18.0