On certain MT7601U adapters, such as Tenda U2 (USB ID 148f:7601) and other newer hardware revisions, driver initialization consistently fails during probe with vendor request timeouts (-110 / -ETIMEDOUT): mt7601u 3-14:1.0: ASIC revision: 76010001 MAC revision: 76010500 mt7601u 3-14:1.0: Firmware Version: 0.1.00 Build: 7640 mt7601u 3-14:1.0: Vendor request req:07 off:09a8 failed:-110 mt7601u 3-14:1.0: Vendor request req:02 off:09a8 failed:-110 mt7601u 3-14:1.0: Vendor request req:07 off:0734 failed:-110 mt7601u 3-14:1.0: Vendor request req:42 off:0230 failed:-110 mt7601u 3-14:1.0: probe with driver mt7601u failed with error -110 The failure occurs because mt7601u_load_firmware() unconditionally calls mt7601u_vendor_reset() (MT_VEND_DEV_MODE_RESET) before uploading firmware chunks. On these devices, issuing this vendor reset leaves the internal MCU / FCE DMA engine in an unresponsive state after the first firmware URB is submitted. As a result, reading MT_TX_CPU_FROM_FCE_CPU_DESC_IDX (0x09a8) immediately times out. The USB device is already reset during mt7601u_probe() via usb_reset_device(), making this additional vendor-specific reset redundant. The vendor driver never used it, and devices that work with vendor reset also work properly without it. Drop mt7601u_vendor_reset() and its definition to allow firmware upload and probe to succeed on all MT7601U adapters. Link: https://bugs.launchpad.net/ubuntu/+source/linux/+bug/1716301 Link: https://www.opena.tv/viewtopic.php?t=63919 Link: https://askubuntu.com/questions/1418850/the-problem-with-wi-fi-u2 Link: https://bbs.archlinux.org/viewtopic.php?id=224859 Link: https://reddit.com/r/archlinux/comments/1d6dfv5/mt7601u_usb_wifi_not_working/ Signed-off-by: Herman Semenoff --- drivers/net/wireless/mediatek/mt7601u/mcu.c | 3 --- drivers/net/wireless/mediatek/mt7601u/usb.c | 6 ------ drivers/net/wireless/mediatek/mt7601u/usb.h | 3 --- 3 files changed, 12 deletions(-) diff --git a/drivers/net/wireless/mediatek/mt7601u/mcu.c b/drivers/net/wireless/mediatek/mt7601u/mcu.c index bad6ca821400..979bc506d4ed 100644 --- a/drivers/net/wireless/mediatek/mt7601u/mcu.c +++ b/drivers/net/wireless/mediatek/mt7601u/mcu.c @@ -459,9 +459,6 @@ static int mt7601u_load_firmware(struct mt7601u_dev *dev) mt7601u_wr(dev, 0x94c, 0); mt7601u_wr(dev, MT_FCE_PSE_CTRL, 0); - mt7601u_vendor_reset(dev); - msleep(5); - mt7601u_wr(dev, 0xa44, 0); mt7601u_wr(dev, 0x230, 0x84210); mt7601u_wr(dev, 0x400, 0x80c00); diff --git a/drivers/net/wireless/mediatek/mt7601u/usb.c b/drivers/net/wireless/mediatek/mt7601u/usb.c index 9306870cbc91..0d38644c491e 100644 --- a/drivers/net/wireless/mediatek/mt7601u/usb.c +++ b/drivers/net/wireless/mediatek/mt7601u/usb.c @@ -116,12 +116,6 @@ int mt7601u_vendor_request(struct mt7601u_dev *dev, const u8 req, return ret; } -void mt7601u_vendor_reset(struct mt7601u_dev *dev) -{ - mt7601u_vendor_request(dev, MT_VEND_DEV_MODE, USB_DIR_OUT, - MT_VEND_DEV_MODE_RESET, 0, NULL, 0); -} - /* should be called with vendor_req_mutex held */ static u32 __mt7601u_rr(struct mt7601u_dev *dev, u32 offset) { diff --git a/drivers/net/wireless/mediatek/mt7601u/usb.h b/drivers/net/wireless/mediatek/mt7601u/usb.h index 723025f84483..49fede310c3b 100644 --- a/drivers/net/wireless/mediatek/mt7601u/usb.h +++ b/drivers/net/wireless/mediatek/mt7601u/usb.h @@ -14,8 +14,6 @@ #define MT_VEND_REQ_MAX_RETRY 10 #define MT_VEND_REQ_TOUT_MS 300 -#define MT_VEND_DEV_MODE_RESET 1 - #define MT_VEND_BUF sizeof(__le32) enum mt_vendor_req { @@ -65,7 +63,6 @@ void mt7601u_complete_urb(struct urb *urb); int mt7601u_vendor_request(struct mt7601u_dev *dev, const u8 req, const u8 direction, const u16 val, const u16 offset, void *buf, const size_t buflen); -void mt7601u_vendor_reset(struct mt7601u_dev *dev); int mt7601u_vendor_single_wr(struct mt7601u_dev *dev, const u8 req, const u16 offset, const u32 val); -- 2.55.0 base-commit: af5f12805e5cefa4fe68d6127c7e1fb78cd5535c