github-mirror/linux
1
0
Fork 0
mirror of https://github.com/torvalds/linux.git synced 2026-10-08 19:46:02 +02:00
Code Issues Actions Packages Projects Releases Wiki Activity Graph

wifi: mt76: mt792x: stop USB register access after bus hang

Browse Source 
Mark the mt792x USB bus hung on the first control timeout and switch
register access to no-op bus ops. Each failed vendor request may spend
up to MT_VEND_REQ_MAX_RETRY * MT_VEND_REQ_TOUT_MS, about 3 seconds, and
teardown/reset paths can keep issuing such requests after the device has
stopped responding.

Also skip the USB WFSYS reset path after bus_hung is set, since it uses
UHW vendor requests as well.

mt7925u 1-2:1.3: vendor request req:63 off:0018 failed:-110
mt7925u 1-2:1.3: vendor request req:63 off:0018 failed:-110
mt7925u 1-2:1.3: vendor request req:63 off:0018 failed:-110
mt7925u 1-2:1.3: vendor request req:63 off:0018 failed:-110
mt7925u 1-2:1.3: vendor request req:63 off:0018 failed:-110

Avoid repeating those register reads after the bus is known to be hung by
switching register access to no-op handlers.

Fixes: 0d2afe09fa ("mt76: mt7921: add mt7921u driver")
Fixes: c948b5da6b ("wifi: mt76: mt7925: add Mediatek Wi-Fi7 driver for mt7925 chips")
Signed-off-by: Sean Wang <sean.wang@mediatek.com>
Link: https://patch.msgid.link/20260613224131.2396026-4-sean.wang@kernel.org
Signed-off-by: Felix Fietkau <nbd@nbd.name>
This commit is contained in:
Sean Wang 2026-06-13 17:41:28 -05:00 committed by Felix Fietkau
parent c781b74c3f
commit e137e5fd24
3 changed files with 90 additions and 13 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

1
drivers/net/wireless/mediatek/mt76/mt76.h
View File

@ -672,6 +672,7 @@ struct mt76_usb {
u8 out_ep[__MT_EP_OUT_MAX];
u8 in_ep[__MT_EP_IN_MAX];
void (*ctrl_timeout)(struct mt76_dev *dev, int err);
bool sg_en;
struct mt76u_mcu {

91
drivers/net/wireless/mediatek/mt76/mt792x_usb.c
View File

@ -31,10 +31,75 @@ static void mt792xu_reset_work(struct work_struct *work)
atomic_set(&dev->usb_reset_pending, 0);
}
static void mt792xu_queue_usb_reset(struct mt792x_dev *dev, int err)
{
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);
}
}
static u32 mt792xu_bus_hung_rr(struct mt76_dev *mdev, u32 offset)
{
return 0;
}
static void mt792xu_bus_hung_wr(struct mt76_dev *mdev, u32 offset, u32 val)
{
}
static u32 mt792xu_bus_hung_rmw(struct mt76_dev *mdev, u32 offset,
u32 mask, u32 val)
{
return 0;
}
static void mt792xu_bus_hung_write_copy(struct mt76_dev *mdev, u32 offset,
const void *data, int len)
{
}
static void mt792xu_bus_hung_read_copy(struct mt76_dev *mdev, u32 offset,
void *data, int len)
{
memset(data, 0, len);
}
static const struct mt76_bus_ops mt792xu_bus_hung_ops = {
.rr = mt792xu_bus_hung_rr,
.wr = mt792xu_bus_hung_wr,
.rmw = mt792xu_bus_hung_rmw,
.write_copy = mt792xu_bus_hung_write_copy,
.read_copy = mt792xu_bus_hung_read_copy,
.type = MT76_BUS_USB,
};
static void mt792xu_set_bus_hung(struct mt792x_dev *dev)
{
atomic_set(&dev->mt76.bus_hung, true);
if (READ_ONCE(dev->mt76.bus) == &mt792xu_bus_hung_ops)
return;
WRITE_ONCE(dev->mt76.bus, &mt792xu_bus_hung_ops);
}
static void mt792xu_ctrl_timeout(struct mt76_dev *mdev, int err)
{
struct mt792x_dev *dev = container_of(mdev, struct mt792x_dev, mt76);
mt792xu_set_bus_hung(dev);
mt792xu_queue_usb_reset(dev, err);
}
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);
dev->mt76.usb.ctrl_timeout = mt792xu_ctrl_timeout;
}
EXPORT_SYMBOL_GPL(mt792xu_reset_work_init);
@ -62,26 +127,23 @@ EXPORT_SYMBOL_GPL(mt792xu_check_bus);
int mt792xu_reset_on_bus_error(struct mt792x_dev *dev)
{
int err = 0;
int err;
if (!atomic_read(&dev->mt76.bus_hung))
err = mt792xu_check_bus(dev);
/* Once hung, the no-op bus ops stay installed until the queued USB
* reset re-probes the device. Do not clear bus_hung here, or the caller
* would run a full reset over dropped register I/O and report success.
*/
if (atomic_read(&dev->mt76.bus_hung))
return -EIO;
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);
}
mt792xu_set_bus_hung(dev);
mt792xu_queue_usb_reset(dev, err);
return err;
}
atomic_set(&dev->mt76.bus_hung, false);
return 0;
}
EXPORT_SYMBOL_GPL(mt792xu_reset_on_bus_error);
@ -344,6 +406,9 @@ int mt792xu_wfsys_reset(struct mt792x_dev *dev)
u32 val;
int i;
if (atomic_read(&dev->mt76.bus_hung))
return -EIO;
mt792xu_epctl_rst_opt(dev, false);
val = mt792xu_uhw_rr(&dev->mt76, desc->rst_reg);

11
drivers/net/wireless/mediatek/mt76/usb.c
View File

@ -30,6 +30,8 @@ int __mt76u_vendor_request(struct mt76_dev *dev, u8 req, u8 req_type,
for (i = 0; i < MT_VEND_REQ_MAX_RETRY; i++) {
if (test_bit(MT76_REMOVED, &dev->phy.state))
return -EIO;
if (dev->usb.ctrl_timeout && atomic_read(&dev->bus_hung))
return -EIO;
ret = usb_control_msg(udev, pipe, req, req_type, val,
offset, buf, len, MT_VEND_REQ_TOUT_MS);
@ -42,6 +44,15 @@ int __mt76u_vendor_request(struct mt76_dev *dev, u8 req, u8 req_type,
dev_err(dev->dev, "vendor request req:%02x off:%04x failed:%d\n",
req, offset, ret);
if (dev->usb.ctrl_timeout) {
atomic_set(&dev->bus_hung, true);
dev_err(dev->dev, "vendor request req:%02x off:%04x timed out, marking bus hung\n",
req, offset);
dev->usb.ctrl_timeout(dev, ret);
return ret;
}
return ret;
}
EXPORT_SYMBOL_GPL(__mt76u_vendor_request);