diff options
| author | Chunfeng Yun <chunfeng.yun@mediatek.com> | 2021-08-26 11:36:37 +0300 |
|---|---|---|
| committer | Greg Kroah-Hartman <gregkh@linuxfoundation.org> | 2021-08-26 14:41:52 +0300 |
| commit | d98a30ccdc839947c9233369744341d1fa54439c (patch) | |
| tree | b697f6f128ca3b9c667c70f37834713fe794f34c /drivers/usb/mtu3 | |
| parent | 50fdcb56c41904c3535687a0e1e1dbd9423a8f9a (diff) | |
| download | linux-d98a30ccdc839947c9233369744341d1fa54439c.tar.xz | |
usb: mtu3: fix random remote wakeup
Some platforms, e.g. 8183/8192, use low level latch way to keep
wakeup signal, it may latch a wrong signal if debounce more time,
and enable wakeup earlier.
____________________
ip_sleep ____/ \__________
___________________
wakeup_signal ____________/ \______
_______________________________
wakeup_en _______/
^ ^
|(1) |(2)
latch wakeup_signal mistakenly at (1), should latch it at (2);
Workaround: delay about 100us to enable wakeup, meanwhile decrease
debounce time.
Fixes: b1a344589eea ("usb: mtu3: support ip-sleep wakeup for MT8183")
Cc: stable@vger.kernel.org
Signed-off-by: Chunfeng Yun <chunfeng.yun@mediatek.com>
Link: https://lore.kernel.org/r/20210826083637.33237-2-chunfeng.yun@mediatek.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Diffstat (limited to 'drivers/usb/mtu3')
| -rw-r--r-- | drivers/usb/mtu3/mtu3_host.c | 2 | ||||
| -rw-r--r-- | drivers/usb/mtu3/mtu3_plat.c | 3 |
2 files changed, 4 insertions, 1 deletions
diff --git a/drivers/usb/mtu3/mtu3_host.c b/drivers/usb/mtu3/mtu3_host.c index 7d528f3c2482..f3903367a6a0 100644 --- a/drivers/usb/mtu3/mtu3_host.c +++ b/drivers/usb/mtu3/mtu3_host.c @@ -62,7 +62,7 @@ static void ssusb_wakeup_ip_sleep_set(struct ssusb_mtk *ssusb, bool enable) case SSUSB_UWK_V1_1: reg = ssusb->uwk_reg_base + PERI_WK_CTRL0; msk = WC0_IS_EN | WC0_IS_C(0xf) | WC0_IS_P; - val = enable ? (WC0_IS_EN | WC0_IS_C(0x8)) : 0; + val = enable ? (WC0_IS_EN | WC0_IS_C(0x1)) : 0; break; case SSUSB_UWK_V1_2: reg = ssusb->uwk_reg_base + PERI_WK_CTRL0; diff --git a/drivers/usb/mtu3/mtu3_plat.c b/drivers/usb/mtu3/mtu3_plat.c index 5b3f7f73cb40..f13531022f4a 100644 --- a/drivers/usb/mtu3/mtu3_plat.c +++ b/drivers/usb/mtu3/mtu3_plat.c @@ -63,6 +63,9 @@ static int wait_for_ip_sleep(struct ssusb_mtk *ssusb) if (ret) { dev_err(ssusb->dev, "ip sleep failed!!!\n"); ret = -EBUSY; + } else { + /* workaround: avoid wrong wakeup signal latch for some soc */ + usleep_range(100, 200); } return ret; |