From 0d8cfeeef3f5a5966abce1903f80308be33280cb Mon Sep 17 00:00:00 2001 From: Chunfeng Yun Date: Tue, 2 Nov 2021 10:50:04 +0800 Subject: [PATCH] usb: xhci-mtk: 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 function 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. Signed-off-by: Chunfeng Yun Link: https://lore.kernel.org/r/20211102025004.29156-2-chunfeng.yun@mediatek.com Signed-off-by: Greg Kroah-Hartman --- drivers/usb/host/xhci-mtk.c | 11 ++++++----- 1 file changed, 6 insertions(+), 5 deletions(-) diff --git a/drivers/usb/host/xhci-mtk.c b/drivers/usb/host/xhci-mtk.c index 8b98de4..91738af0 100644 --- a/drivers/usb/host/xhci-mtk.c +++ b/drivers/usb/host/xhci-mtk.c @@ -245,11 +245,12 @@ static int xhci_mtk_host_disable(struct xhci_hcd_mtk *mtk) /* wait for host ip to sleep */ ret = readl_poll_timeout(&ippc->ip_pw_sts1, value, (value & STS1_IP_SLEEP_STS), 100, 100000); - if (ret) { + if (ret) dev_err(mtk->dev, "ip sleep failed!!!\n"); - return ret; - } - return 0; + else /* workaound for platforms using low level latch */ + usleep_range(100, 200); + + return ret; } static int xhci_mtk_ssusb_config(struct xhci_hcd_mtk *mtk) @@ -300,7 +301,7 @@ static void usb_wakeup_ip_sleep_set(struct xhci_hcd_mtk *mtk, bool enable) case SSUSB_UWK_V1_1: reg = mtk->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 = mtk->uwk_reg_base + PERI_WK_CTRL0; -- 2.7.4