* [PATCH 1/2] wifi: mt76: mt792x: add common USB transport reset helpers
@ 2026-03-19 4:53 Sean Wang
2026-03-19 4:53 ` [PATCH 2/2] wifi: mt76: mt7921u: escalate broken USB transport to device reset Sean Wang
0 siblings, 1 reply; 2+ messages in thread
From: Sean Wang @ 2026-03-19 4:53 UTC (permalink / raw)
To: nbd, lorenzo.bianconi; +Cc: linux-wireless, linux-mediatek, Sean Wang
From: Sean Wang <sean.wang@mediatek.com>
Add per-device USB reset work and a control-path access check helper
for mt7921u and mt7925u.
This prepares common infrastructure for transport-level recovery while
keeping the reset state per-device for correct lifetime handling.
No functional change intended.
Signed-off-by: Sean Wang <sean.wang@mediatek.com>
---
.../net/wireless/mediatek/mt76/mt7921/usb.c | 2 +
.../net/wireless/mediatek/mt76/mt7925/usb.c | 2 +
drivers/net/wireless/mediatek/mt76/mt792x.h | 5 ++
.../net/wireless/mediatek/mt76/mt792x_usb.c | 50 +++++++++++++++++++
4 files changed, 59 insertions(+)
diff --git a/drivers/net/wireless/mediatek/mt76/mt7921/usb.c b/drivers/net/wireless/mediatek/mt76/mt7921/usb.c
index 17057e68bf21..6be28f4152ed 100644
--- a/drivers/net/wireless/mediatek/mt76/mt7921/usb.c
+++ b/drivers/net/wireless/mediatek/mt76/mt7921/usb.c
@@ -196,6 +196,7 @@ static int mt7921u_probe(struct usb_interface *usb_intf,
dev = container_of(mdev, struct mt792x_dev, mt76);
dev->fw_features = features;
dev->hif_ops = &hif_ops;
+ mt792xu_reset_work_init(dev);
udev = usb_get_dev(udev);
usb_reset_device(udev);
@@ -244,6 +245,7 @@ static int mt7921u_probe(struct usb_interface *usb_intf,
error:
mt76u_queues_deinit(&dev->mt76);
+ mt792xu_reset_work_cleanup(dev);
usb_set_intfdata(usb_intf, NULL);
usb_put_dev(interface_to_usbdev(usb_intf));
diff --git a/drivers/net/wireless/mediatek/mt76/mt7925/usb.c b/drivers/net/wireless/mediatek/mt76/mt7925/usb.c
index d9968f03856d..8b5d58125352 100644
--- a/drivers/net/wireless/mediatek/mt76/mt7925/usb.c
+++ b/drivers/net/wireless/mediatek/mt76/mt7925/usb.c
@@ -184,6 +184,7 @@ static int mt7925u_probe(struct usb_interface *usb_intf,
dev = container_of(mdev, struct mt792x_dev, mt76);
dev->fw_features = features;
dev->hif_ops = &hif_ops;
+ mt792xu_reset_work_init(dev);
udev = usb_get_dev(udev);
usb_reset_device(udev);
@@ -232,6 +233,7 @@ static int mt7925u_probe(struct usb_interface *usb_intf,
error:
mt76u_queues_deinit(&dev->mt76);
+ mt792xu_reset_work_cleanup(dev);
usb_set_intfdata(usb_intf, NULL);
usb_put_dev(interface_to_usbdev(usb_intf));
diff --git a/drivers/net/wireless/mediatek/mt76/mt792x.h b/drivers/net/wireless/mediatek/mt76/mt792x.h
index 4ff93f2cd624..5f06074591ca 100644
--- a/drivers/net/wireless/mediatek/mt76/mt792x.h
+++ b/drivers/net/wireless/mediatek/mt76/mt792x.h
@@ -243,6 +243,8 @@ struct mt792x_dev {
wait_queue_head_t wait;
struct work_struct init_work;
+ struct work_struct usb_reset_work;
+ atomic_t usb_reset_pending;
u8 fw_debug;
u8 fw_features;
@@ -489,6 +491,9 @@ int mt792xu_dma_init(struct mt792x_dev *dev, bool resume);
int mt792xu_mcu_power_on(struct mt792x_dev *dev);
int mt792xu_wfsys_reset(struct mt792x_dev *dev);
int mt792xu_init_reset(struct mt792x_dev *dev);
+void mt792xu_reset_work_init(struct mt792x_dev *dev);
+void mt792xu_reset_work_cleanup(struct mt792x_dev *dev);
+int mt792xu_check_bus(struct mt792x_dev *dev);
u32 mt792xu_rr(struct mt76_dev *dev, u32 addr);
void mt792xu_wr(struct mt76_dev *dev, u32 addr, u32 val);
u32 mt792xu_rmw(struct mt76_dev *dev, u32 addr, u32 mask, u32 val);
diff --git a/drivers/net/wireless/mediatek/mt76/mt792x_usb.c b/drivers/net/wireless/mediatek/mt76/mt792x_usb.c
index 47827d1c5ccb..2558d87b1e0f 100644
--- a/drivers/net/wireless/mediatek/mt76/mt792x_usb.c
+++ b/drivers/net/wireless/mediatek/mt76/mt792x_usb.c
@@ -11,6 +11,55 @@
#include "mt792x.h"
#include "mt76_connac2_mac.h"
+static int mt792xu_read32(struct mt76_dev *dev, u32 addr, void *buf)
+{
+ return __mt76u_vendor_request(dev, MT_VEND_READ_EXT,
+ USB_DIR_IN | MT_USB_TYPE_VENDOR,
+ (u16)(addr >> 16), (u16)addr,
+ buf, sizeof(__le32));
+}
+
+static void mt792xu_reset_work(struct work_struct *work)
+{
+ struct mt792x_dev *dev =
+ container_of(work, struct mt792x_dev, usb_reset_work);
+ struct usb_interface *usb_intf = to_usb_interface(dev->mt76.dev);
+
+ if (usb_intf && usb_get_intfdata(usb_intf) == dev)
+ usb_queue_reset_device(usb_intf);
+
+ atomic_set(&dev->usb_reset_pending, 0);
+}
+
+void mt792xu_reset_work_init(struct mt792x_dev *dev)
+{
+ INIT_WORK(&dev->usb_reset_work, mt792xu_reset_work);
+ atomic_set(&dev->usb_reset_pending, 0);
+}
+EXPORT_SYMBOL_GPL(mt792xu_reset_work_init);
+
+void mt792xu_reset_work_cleanup(struct mt792x_dev *dev)
+{
+ cancel_work_sync(&dev->usb_reset_work);
+ atomic_set(&dev->usb_reset_pending, 0);
+}
+EXPORT_SYMBOL_GPL(mt792xu_reset_work_cleanup);
+
+int mt792xu_check_bus(struct mt792x_dev *dev)
+{
+ int ret;
+
+ mutex_lock(&dev->mt76.usb.usb_ctrl_mtx);
+ ret = mt792xu_read32(&dev->mt76, MT_HW_CHIPID, dev->mt76.usb.data);
+ mutex_unlock(&dev->mt76.usb.usb_ctrl_mtx);
+
+ if (ret == sizeof(__le32))
+ return 0;
+
+ return ret < 0 ? ret : -EIO;
+}
+EXPORT_SYMBOL_GPL(mt792xu_check_bus);
+
u32 mt792xu_rr(struct mt76_dev *dev, u32 addr)
{
u32 ret;
@@ -333,6 +382,7 @@ void mt792xu_disconnect(struct usb_interface *usb_intf)
{
struct mt792x_dev *dev = usb_get_intfdata(usb_intf);
+ mt792xu_reset_work_cleanup(dev);
cancel_work_sync(&dev->init_work);
if (!test_bit(MT76_STATE_INITIALIZED, &dev->mphy.state))
return;
--
2.43.0
^ permalink raw reply related [flat|nested] 2+ messages in thread
* [PATCH 2/2] wifi: mt76: mt7921u: escalate broken USB transport to device reset
2026-03-19 4:53 [PATCH 1/2] wifi: mt76: mt792x: add common USB transport reset helpers Sean Wang
@ 2026-03-19 4:53 ` Sean Wang
0 siblings, 0 replies; 2+ messages in thread
From: Sean Wang @ 2026-03-19 4:53 UTC (permalink / raw)
To: nbd, lorenzo.bianconi; +Cc: linux-wireless, linux-mediatek, Sean Wang
From: Sean Wang <sean.wang@mediatek.com>
Check the USB control path before running the normal WFSYS reset flow.
If USB access is no longer reliable, stop the WFSYS-only reset path,
mark the device as bus_hung, and queue a USB device reset instead.
Reuse the existing bus_hung state to represent transport-level failure,
keeping the semantics consistent with the SDIO path.
Also initialize bus_hung explicitly during probe for consistency.
Signed-off-by: Sean Wang <sean.wang@mediatek.com>
---
.../net/wireless/mediatek/mt76/mt7921/mac.c | 4 ++-
.../net/wireless/mediatek/mt76/mt7921/usb.c | 5 ++++
drivers/net/wireless/mediatek/mt76/mt792x.h | 1 +
.../net/wireless/mediatek/mt76/mt792x_usb.c | 26 +++++++++++++++++++
4 files changed, 35 insertions(+), 1 deletion(-)
diff --git a/drivers/net/wireless/mediatek/mt76/mt7921/mac.c b/drivers/net/wireless/mediatek/mt76/mt7921/mac.c
index 03b4960db73f..d27dbee8df1b 100644
--- a/drivers/net/wireless/mediatek/mt76/mt7921/mac.c
+++ b/drivers/net/wireless/mediatek/mt76/mt7921/mac.c
@@ -675,7 +675,9 @@ void mt7921_mac_reset_work(struct work_struct *work)
if (!ret)
break;
}
- if (mt76_is_sdio(&dev->mt76) && atomic_read(&dev->mt76.bus_hung))
+
+ if ((mt76_is_sdio(&dev->mt76) || mt76_is_usb(&dev->mt76)) &&
+ atomic_read(&dev->mt76.bus_hung))
return;
if (i == 10)
diff --git a/drivers/net/wireless/mediatek/mt76/mt7921/usb.c b/drivers/net/wireless/mediatek/mt76/mt7921/usb.c
index 6be28f4152ed..8c0f0e4ef87b 100644
--- a/drivers/net/wireless/mediatek/mt76/mt7921/usb.c
+++ b/drivers/net/wireless/mediatek/mt76/mt7921/usb.c
@@ -88,6 +88,10 @@ static int mt7921u_mac_reset(struct mt792x_dev *dev)
{
int err;
+ mt792xu_reset_on_bus_error(dev);
+ if (atomic_read(&dev->mt76.bus_hung))
+ return 0;
+
mt76_txq_schedule_all(&dev->mphy);
mt76_worker_disable(&dev->mt76.tx_worker);
@@ -196,6 +200,7 @@ static int mt7921u_probe(struct usb_interface *usb_intf,
dev = container_of(mdev, struct mt792x_dev, mt76);
dev->fw_features = features;
dev->hif_ops = &hif_ops;
+ atomic_set(&dev->mt76.bus_hung, false);
mt792xu_reset_work_init(dev);
udev = usb_get_dev(udev);
diff --git a/drivers/net/wireless/mediatek/mt76/mt792x.h b/drivers/net/wireless/mediatek/mt76/mt792x.h
index 5f06074591ca..74222c507b81 100644
--- a/drivers/net/wireless/mediatek/mt76/mt792x.h
+++ b/drivers/net/wireless/mediatek/mt76/mt792x.h
@@ -494,6 +494,7 @@ int mt792xu_init_reset(struct mt792x_dev *dev);
void mt792xu_reset_work_init(struct mt792x_dev *dev);
void mt792xu_reset_work_cleanup(struct mt792x_dev *dev);
int mt792xu_check_bus(struct mt792x_dev *dev);
+int mt792xu_reset_on_bus_error(struct mt792x_dev *dev);
u32 mt792xu_rr(struct mt76_dev *dev, u32 addr);
void mt792xu_wr(struct mt76_dev *dev, u32 addr, u32 val);
u32 mt792xu_rmw(struct mt76_dev *dev, u32 addr, u32 mask, u32 val);
diff --git a/drivers/net/wireless/mediatek/mt76/mt792x_usb.c b/drivers/net/wireless/mediatek/mt76/mt792x_usb.c
index 2558d87b1e0f..6b10d035bcbc 100644
--- a/drivers/net/wireless/mediatek/mt76/mt792x_usb.c
+++ b/drivers/net/wireless/mediatek/mt76/mt792x_usb.c
@@ -60,6 +60,32 @@ int mt792xu_check_bus(struct mt792x_dev *dev)
}
EXPORT_SYMBOL_GPL(mt792xu_check_bus);
+int mt792xu_reset_on_bus_error(struct mt792x_dev *dev)
+{
+ int err = 0;
+
+ if (!atomic_read(&dev->mt76.bus_hung))
+ err = mt792xu_check_bus(dev);
+
+ if (err) {
+ atomic_set(&dev->mt76.bus_hung, true);
+
+ if (!atomic_xchg(&dev->usb_reset_pending, 1)) {
+ dev_warn(dev->mt76.dev,
+ "USB transport access failed (%d), queueing device reset\n",
+ err);
+
+ schedule_work(&dev->usb_reset_work);
+ }
+
+ return err;
+ }
+
+ atomic_set(&dev->mt76.bus_hung, false);
+ return 0;
+}
+EXPORT_SYMBOL_GPL(mt792xu_reset_on_bus_error);
+
u32 mt792xu_rr(struct mt76_dev *dev, u32 addr)
{
u32 ret;
--
2.43.0
^ permalink raw reply related [flat|nested] 2+ messages in thread
end of thread, other threads:[~2026-03-19 4:54 UTC | newest]
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