Commit d98a30cc authored by Chunfeng Yun's avatar Chunfeng Yun Committed by Greg Kroah-Hartman
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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: b1a34458 ("usb: mtu3: support ip-sleep wakeup for MT8183")
Cc: stable@vger.kernel.org
Signed-off-by: default avatarChunfeng Yun <chunfeng.yun@mediatek.com>
Link: https://lore.kernel.org/r/20210826083637.33237-2-chunfeng.yun@mediatek.com


Signed-off-by: default avatarGreg Kroah-Hartman <gregkh@linuxfoundation.org>
parent 50fdcb56

drivers/usb/mtu3/mtu3_host.c

+1 −1
Original line number Diff line number Diff line
@@ -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;

drivers/usb/mtu3/mtu3_plat.c

+3 −0
Original line number Diff line number Diff line
@@ -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;