Commit 24fe86a6 authored by Hans de Goede's avatar Hans de Goede Committed by Felipe Balbi

phy: sun4i-usb: Add a sunxi specific function for setting squelch-detect

The sunxi otg phy has a bug where it wrongly detects a high speed squelch
when reset on the root port gets de-asserted with a lo-speed device.

The workaround for this is to disable squelch detect before de-asserting
reset, and re-enabling it after the reset de-assert is done. Add a sunxi
specific phy function to allow the sunxi-musb glue to do this.
Acked-by: default avatarKishon Vijay Abraham I <>
Signed-off-by: default avatarHans de Goede <>
Signed-off-by: default avatarFelipe Balbi <>
parent 7a64c728
......@@ -30,6 +30,7 @@
#include <linux/of.h>
#include <linux/of_address.h>
#include <linux/phy/phy.h>
#include <linux/phy/phy-sun4i-usb.h>
#include <linux/platform_device.h>
#include <linux/regulator/consumer.h>
#include <linux/reset.h>
......@@ -58,6 +59,7 @@
#define PHY_OTG_FUNC_EN 0x28
#define PHY_VBUS_DET_EN 0x29
#define PHY_DISCON_TH_SEL 0x2a
#define MAX_PHYS 3
......@@ -204,6 +206,13 @@ static int sun4i_usb_phy_power_off(struct phy *_phy)
return 0;
void sun4i_usb_phy_set_squelch_detect(struct phy *_phy, bool enabled)
struct sun4i_usb_phy *phy = phy_get_drvdata(_phy);
sun4i_usb_phy_write(phy, PHY_SQUELCH_DETECT, enabled ? 0 : 2, 2);
static struct phy_ops sun4i_usb_phy_ops = {
.init = sun4i_usb_phy_init,
.exit = sun4i_usb_phy_exit,
* Copyright (c) 2015 Hans de Goede <>
* This program is free software; you can redistribute it and/or modify
* it under the terms of the GNU General Public License version 2 and
* only version 2 as published by the Free Software Foundation.
* This program is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* GNU General Public License for more details.
#ifndef PHY_SUN4I_USB_H_
#define PHY_SUN4I_USB_H_
#include "phy.h"
* sun4i_usb_phy_set_squelch_detect() - Enable/disable squelch detect
* @phy: reference to a sun4i usb phy
* @enabled: wether to enable or disable squelch detect
void sun4i_usb_phy_set_squelch_detect(struct phy *phy, bool enabled);
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