[RFC PATCH] usb: mtu3: fix random remote wakeup

[Chunfeng Yun]

Wakeup_signal will toggle status according to ssusb_ip_sleep signal
after debounce time, so need add a delay time and wait for wakeup_signal
toggle to complete, then enable the remote wakeup. Meanwhile reduce the
debounce time of wakeup_signal. These will avoid spurious wakeup event.

Signed-off-by: Tianping Fang <tianping.fang@xxxxxxxxxxxx>
Signed-off-by: Chunfeng Yun <chunfeng.yun@xxxxxxxxxxxx>
---
Note, depends on following patch not merged:

    [v3,3/7] usb: mtu3: support ip-sleep wakeup for MT8183
    https://patchwork.kernel.org/patch/11123151/
---
 drivers/usb/mtu3/mtu3_host.c | 6 ++++--
 1 file changed, 4 insertions(+), 2 deletions(-)

diff --git a/drivers/usb/mtu3/mtu3_host.c b/drivers/usb/mtu3/mtu3_host.c
index 182c9439c15a..ca48ff751c8b 100644
--- a/drivers/usb/mtu3/mtu3_host.c
+++ b/drivers/usb/mtu3/mtu3_host.c
@@ -53,12 +53,12 @@ static void ssusb_wakeup_ip_sleep_set(struct ssusb_mtk *ssusb, bool enable)
 	case SSUSB_UWK_V0:
 		reg = ssusb->uwk_reg_base + PERI_WK_CTRL0;
 		msk = (u32)(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(0x3)) : 0;
 		break;
 	case SSUSB_UWK_V1:
 		reg = ssusb->uwk_reg_base + PERI_WK_CTRL1;
 		msk = WC1_IS_EN | WC1_IS_C(0xf) | WC1_IS_P;
-		val = enable ? (WC1_IS_EN | WC1_IS_C(0x8)) : 0;
+		val = enable ? (WC1_IS_EN | WC1_IS_C(0x3)) : 0;
 		break;
 	case SSUSB_UWK_V2:
 		reg = ssusb->uwk_reg_base + PERI_SSUSB_SPM_CTRL;
@@ -197,6 +197,8 @@ int ssusb_host_disable(struct ssusb_mtk *ssusb, bool suspend)
 			  (value & SSUSB_IP_SLEEP_STS), 100, 100000);
 	if (ret)
 		dev_err(ssusb->dev, "ip sleep failed!!!\n");
+	else  /* wait for wakeup_signal toggle done after enter ip-sleep */
+		usleep_range(245, 255);
 
 	return ret;
 }
-- 
2.23.0