blob: 4a37f036345b47f23512c0275dba975fc54fee1a [file] [log] [blame]
/**
* dwc3_otg.c - DesignWare USB3 DRD Controller OTG
*
* Copyright (c) 2012, Code Aurora Forum. All rights reserved.
*
* 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
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
* GNU General Public License for more details.
*/
#include <linux/usb.h>
#include <linux/usb/hcd.h>
#include <linux/platform_device.h>
#include "core.h"
#include "dwc3_otg.h"
#include "io.h"
#include "xhci.h"
/**
* dwc3_otg_set_host_regs - reset dwc3 otg registers to host operation.
*
* This function sets the OTG registers to work in A-Device host mode.
* This function should be called just before entering to A-Device mode.
*
* @w: Pointer to the dwc3 otg workqueue.
*/
static void dwc3_otg_set_host_regs(struct dwc3_otg *dotg)
{
u32 octl;
/* Set OCTL[6](PeriMode) to 0 (host) */
octl = dwc3_readl(dotg->regs, DWC3_OCTL);
octl &= ~DWC3_OTG_OCTL_PERIMODE;
dwc3_writel(dotg->regs, DWC3_OCTL, octl);
/*
* TODO: add more OTG registers writes for HOST mode here,
* see figure 12-10 A-device flow in dwc3 Synopsis spec
*/
}
/**
* dwc3_otg_set_peripheral_regs - reset dwc3 otg registers to peripheral operation.
*
* This function sets the OTG registers to work in B-Device peripheral mode.
* This function should be called just before entering to B-Device mode.
*
* @w: Pointer to the dwc3 otg workqueue.
*/
static void dwc3_otg_set_peripheral_regs(struct dwc3_otg *dotg)
{
u32 octl;
/* Set OCTL[6](PeriMode) to 1 (peripheral) */
octl = dwc3_readl(dotg->regs, DWC3_OCTL);
octl |= DWC3_OTG_OCTL_PERIMODE;
dwc3_writel(dotg->regs, DWC3_OCTL, octl);
/*
* TODO: add more OTG registers writes for PERIPHERAL mode here,
* see figure 12-19 B-device flow in dwc3 Synopsis spec
*/
}
/**
* dwc3_otg_start_host - helper function for starting/stoping the host controller driver.
*
* @otg: Pointer to the otg_transceiver structure.
* @on: start / stop the host controller driver.
*
* Returns 0 on success otherwise negative errno.
*/
static int dwc3_otg_start_host(struct usb_otg *otg, int on)
{
struct dwc3_otg *dotg = container_of(otg, struct dwc3_otg, otg);
struct usb_hcd *hcd;
struct xhci_hcd *xhci;
int ret = 0;
if (!otg->host)
return -EINVAL;
hcd = bus_to_hcd(otg->host);
xhci = hcd_to_xhci(hcd);
if (on) {
dev_dbg(otg->phy->dev, "%s: turn on host %s\n",
__func__, otg->host->bus_name);
dwc3_otg_set_host_regs(dotg);
/*
* This should be revisited for more testing post-silicon.
* In worst case we may need to disconnect the root hub
* before stopping the controller so that it does not
* interfere with runtime pm/system pm.
* We can also consider registering and unregistering xhci
* platform device. It is almost similar to add_hcd and
* remove_hcd, But we may not use standard set_host method
* anymore.
*/
ret = hcd->driver->start(hcd);
if (ret) {
dev_err(otg->phy->dev,
"%s: failed to start primary hcd, ret=%d\n",
__func__, ret);
return ret;
}
ret = xhci->shared_hcd->driver->start(xhci->shared_hcd);
if (ret) {
dev_err(otg->phy->dev,
"%s: failed to start secondary hcd, ret=%d\n",
__func__, ret);
return ret;
}
} else {
dev_dbg(otg->phy->dev, "%s: turn off host %s\n",
__func__, otg->host->bus_name);
hcd->driver->stop(hcd);
}
return 0;
}
/**
* dwc3_otg_set_host - bind/unbind the host controller driver.
*
* @otg: Pointer to the otg_transceiver structure.
* @host: Pointer to the usb_bus structure.
*
* Returns 0 on success otherwise negative errno.
*/
static int dwc3_otg_set_host(struct usb_otg *otg, struct usb_bus *host)
{
struct dwc3_otg *dotg = container_of(otg, struct dwc3_otg, otg);
if (host) {
dev_dbg(otg->phy->dev, "%s: set host %s\n",
__func__, host->bus_name);
otg->host = host;
/*
* Only after both peripheral and host are set then check
* OTG sm. This prevents unnecessary activation of the sm
* in case the ID is high.
*/
if (otg->gadget)
schedule_work(&dotg->sm_work);
} else {
if (otg->phy->state == OTG_STATE_A_HOST) {
dwc3_otg_start_host(otg, 0);
otg->host = NULL;
otg->phy->state = OTG_STATE_UNDEFINED;
schedule_work(&dotg->sm_work);
} else {
otg->host = NULL;
}
}
return 0;
}
/**
* dwc3_otg_start_peripheral - bind/unbind the peripheral controller.
*
* @otg: Pointer to the otg_transceiver structure.
* @gadget: pointer to the usb_gadget structure.
*
* Returns 0 on success otherwise negative errno.
*/
static int dwc3_otg_start_peripheral(struct usb_otg *otg, int on)
{
struct dwc3_otg *dotg = container_of(otg, struct dwc3_otg, otg);
if (!otg->gadget)
return -EINVAL;
if (on) {
dev_dbg(otg->phy->dev, "%s: turn on gadget %s\n",
__func__, otg->gadget->name);
dwc3_otg_set_peripheral_regs(dotg);
usb_gadget_vbus_connect(otg->gadget);
} else {
dev_dbg(otg->phy->dev, "%s: turn off gadget %s\n",
__func__, otg->gadget->name);
usb_gadget_vbus_disconnect(otg->gadget);
}
return 0;
}
/**
* dwc3_otg_set_peripheral - bind/unbind the peripheral controller driver.
*
* @otg: Pointer to the otg_transceiver structure.
* @gadget: pointer to the usb_gadget structure.
*
* Returns 0 on success otherwise negative errno.
*/
static int dwc3_otg_set_peripheral(struct usb_otg *otg,
struct usb_gadget *gadget)
{
struct dwc3_otg *dotg = container_of(otg, struct dwc3_otg, otg);
if (gadget) {
dev_dbg(otg->phy->dev, "%s: set gadget %s\n",
__func__, gadget->name);
otg->gadget = gadget;
/*
* Only after both peripheral and host are set then check
* OTG sm. This prevents unnecessary activation of the sm
* in case the ID is grounded.
*/
if (otg->host)
schedule_work(&dotg->sm_work);
} else {
if (otg->phy->state == OTG_STATE_B_PERIPHERAL) {
dwc3_otg_start_peripheral(otg, 0);
otg->gadget = NULL;
otg->phy->state = OTG_STATE_UNDEFINED;
schedule_work(&dotg->sm_work);
} else {
otg->gadget = NULL;
}
}
return 0;
}
/**
* dwc3_ext_chg_det_done - callback to handle charger detection completion
* @otg: Pointer to the otg transceiver structure
* @charger: Pointer to the external charger structure
*
* Returns 0 on success
*/
static void dwc3_ext_chg_det_done(struct usb_otg *otg, struct dwc3_charger *chg)
{
struct dwc3_otg *dotg = container_of(otg, struct dwc3_otg, otg);
/*
* Ignore chg_detection notification if BSV has gone off by this time.
* STOP chg_det as part of !BSV handling would reset the chg_det flags
*/
if (test_bit(B_SESS_VLD, &dotg->inputs))
schedule_work(&dotg->sm_work);
}
/**
* dwc3_set_charger - bind/unbind external charger driver
* @otg: Pointer to the otg transceiver structure
* @charger: Pointer to the external charger structure
*
* Returns 0 on success
*/
int dwc3_set_charger(struct usb_otg *otg, struct dwc3_charger *charger)
{
struct dwc3_otg *dotg = container_of(otg, struct dwc3_otg, otg);
dotg->charger = charger;
if (charger)
charger->notify_detection_complete = dwc3_ext_chg_det_done;
return 0;
}
/**
* dwc3_ext_event_notify - callback to handle events from external transceiver
* @otg: Pointer to the otg transceiver structure
* @event: Event reported by transceiver
*
* Returns 0 on success
*/
static void dwc3_ext_event_notify(struct usb_otg *otg,
enum dwc3_ext_events event)
{
struct dwc3_otg *dotg = container_of(otg, struct dwc3_otg, otg);
struct dwc3_ext_xceiv *ext_xceiv = dotg->ext_xceiv;
struct usb_phy *phy = dotg->otg.phy;
if (event == DWC3_EVENT_PHY_RESUME) {
if (!pm_runtime_status_suspended(phy->dev)) {
dev_warn(phy->dev, "PHY_RESUME event out of LPM!!!!\n");
} else {
dev_dbg(phy->dev, "ext PHY_RESUME event received\n");
/* ext_xceiver would have taken h/w out of LPM by now */
pm_runtime_get(phy->dev);
}
}
if (ext_xceiv->id == DWC3_ID_FLOAT)
set_bit(ID, &dotg->inputs);
else
clear_bit(ID, &dotg->inputs);
if (ext_xceiv->bsv)
set_bit(B_SESS_VLD, &dotg->inputs);
else
clear_bit(B_SESS_VLD, &dotg->inputs);
schedule_work(&dotg->sm_work);
}
/**
* dwc3_set_ext_xceiv - bind/unbind external transceiver driver
* @otg: Pointer to the otg transceiver structure
* @ext_xceiv: Pointer to the external transceiver struccture
*
* Returns 0 on success
*/
int dwc3_set_ext_xceiv(struct usb_otg *otg, struct dwc3_ext_xceiv *ext_xceiv)
{
struct dwc3_otg *dotg = container_of(otg, struct dwc3_otg, otg);
dotg->ext_xceiv = ext_xceiv;
if (ext_xceiv)
ext_xceiv->notify_ext_events = dwc3_ext_event_notify;
return 0;
}
/* IRQs which OTG driver is interested in handling */
#define DWC3_OEVT_MASK (DWC3_OEVTEN_OTGCONIDSTSCHNGEVNT | \
DWC3_OEVTEN_OTGBDEVVBUSCHNGEVNT)
/**
* dwc3_otg_interrupt - interrupt handler for dwc3 otg events.
* @_dotg: Pointer to out controller context structure
*
* Returns IRQ_HANDLED on success otherwise IRQ_NONE.
*/
static irqreturn_t dwc3_otg_interrupt(int irq, void *_dotg)
{
struct dwc3_otg *dotg = (struct dwc3_otg *)_dotg;
struct usb_phy *phy = dotg->otg.phy;
u32 osts, oevt_reg;
int ret = IRQ_NONE;
int handled_irqs = 0;
/*
* If PHY is in retention mode then this interrupt would not be fired.
* ext_xcvr (parent) is responsible for bringing h/w out of LPM.
* OTG driver just need to increment power count and can safely
* assume that h/w is out of low power state now.
* TODO: explicitly disable OEVTEN interrupts if ext_xceiv is present
*/
if (pm_runtime_status_suspended(phy->dev))
pm_runtime_get(phy->dev);
oevt_reg = dwc3_readl(dotg->regs, DWC3_OEVT);
if (!(oevt_reg & DWC3_OEVT_MASK))
return IRQ_NONE;
osts = dwc3_readl(dotg->regs, DWC3_OSTS);
if ((oevt_reg & DWC3_OEVTEN_OTGCONIDSTSCHNGEVNT) ||
(oevt_reg & DWC3_OEVTEN_OTGBDEVVBUSCHNGEVNT)) {
/*
* ID sts has changed, set inputs later, in the workqueue
* function, switch from A to B or from B to A.
*/
if (osts & DWC3_OTG_OSTS_CONIDSTS)
set_bit(ID, &dotg->inputs);
else
clear_bit(ID, &dotg->inputs);
if (osts & DWC3_OTG_OSTS_BSESVALID)
set_bit(B_SESS_VLD, &dotg->inputs);
else
clear_bit(B_SESS_VLD, &dotg->inputs);
schedule_work(&dotg->sm_work);
handled_irqs |= (oevt_reg & DWC3_OEVTEN_OTGCONIDSTSCHNGEVNT) ?
DWC3_OEVTEN_OTGCONIDSTSCHNGEVNT : 0;
handled_irqs |= (oevt_reg & DWC3_OEVTEN_OTGBDEVVBUSCHNGEVNT) ?
DWC3_OEVTEN_OTGBDEVVBUSCHNGEVNT : 0;
ret = IRQ_HANDLED;
/* Clear the interrupts we handled */
dwc3_writel(dotg->regs, DWC3_OEVT, handled_irqs);
}
return ret;
}
/**
* dwc3_otg_init_sm - initialize OTG statemachine input
* @dotg: Pointer to the dwc3_otg structure
*
*/
void dwc3_otg_init_sm(struct dwc3_otg *dotg)
{
u32 osts = dwc3_readl(dotg->regs, DWC3_OSTS);
struct usb_phy *phy = dotg->otg.phy;
/*
* TODO: If using external notifications then wait here till initial
* state is reported
*/
dev_dbg(phy->dev, "Initialize OTG inputs, osts: 0x%x\n", osts);
if (osts & DWC3_OTG_OSTS_CONIDSTS)
set_bit(ID, &dotg->inputs);
else
clear_bit(ID, &dotg->inputs);
if (osts & DWC3_OTG_OSTS_BSESVALID)
set_bit(B_SESS_VLD, &dotg->inputs);
else
clear_bit(B_SESS_VLD, &dotg->inputs);
}
/**
* dwc3_otg_sm_work - workqueue function.
*
* @w: Pointer to the dwc3 otg workqueue
*
* NOTE: After any change in phy->state,
* we must reschdule the state machine.
*/
static void dwc3_otg_sm_work(struct work_struct *w)
{
struct dwc3_otg *dotg = container_of(w, struct dwc3_otg, sm_work);
struct usb_phy *phy = dotg->otg.phy;
struct dwc3_charger *charger = dotg->charger;
bool work = 0;
pm_runtime_resume(phy->dev);
dev_dbg(phy->dev, "%s state\n", otg_state_string(phy->state));
/* Check OTG state */
switch (phy->state) {
case OTG_STATE_UNDEFINED:
dwc3_otg_init_sm(dotg);
/* Switch to A or B-Device according to ID / BSV */
if (!test_bit(ID, &dotg->inputs) && phy->otg->host) {
dev_dbg(phy->dev, "!id\n");
phy->state = OTG_STATE_A_IDLE;
work = 1;
} else if (test_bit(B_SESS_VLD, &dotg->inputs)) {
dev_dbg(phy->dev, "b_sess_vld\n");
phy->state = OTG_STATE_B_IDLE;
work = 1;
} else {
phy->state = OTG_STATE_B_IDLE;
dev_dbg(phy->dev, "No device, trying to suspend\n");
pm_runtime_put_sync(phy->dev);
}
break;
case OTG_STATE_B_IDLE:
if (!test_bit(ID, &dotg->inputs) && phy->otg->host) {
dev_dbg(phy->dev, "!id\n");
phy->state = OTG_STATE_A_IDLE;
work = 1;
if (charger) {
if (charger->chg_type == DWC3_INVALID_CHARGER)
charger->start_detection(dotg->charger,
false);
else
charger->chg_type =
DWC3_INVALID_CHARGER;
}
} else if (test_bit(B_SESS_VLD, &dotg->inputs)) {
dev_dbg(phy->dev, "b_sess_vld\n");
if (charger) {
/* Has charger been detected? If no detect it */
switch (charger->chg_type) {
case DWC3_DCP_CHARGER:
dev_dbg(phy->dev, "lpm, DCP charger\n");
pm_runtime_put_sync(phy->dev);
break;
case DWC3_CDP_CHARGER:
dwc3_otg_start_peripheral(&dotg->otg,
1);
phy->state = OTG_STATE_B_PERIPHERAL;
work = 1;
break;
case DWC3_SDP_CHARGER:
dwc3_otg_start_peripheral(&dotg->otg,
1);
phy->state = OTG_STATE_B_PERIPHERAL;
work = 1;
break;
default:
dev_dbg(phy->dev, "chg_det started\n");
charger->start_detection(charger, true);
break;
}
} else {
/* no charger registered, start peripheral */
if (dwc3_otg_start_peripheral(&dotg->otg, 1)) {
/*
* Probably set_peripheral not called
* yet. We will re-try as soon as it
* will be called
*/
dev_err(phy->dev, "enter lpm as\n"
"unable to start B-device\n");
phy->state = OTG_STATE_UNDEFINED;
pm_runtime_put_sync(phy->dev);
return;
}
}
} else {
if (charger) {
if (charger->chg_type == DWC3_INVALID_CHARGER)
charger->start_detection(dotg->charger,
false);
else
charger->chg_type =
DWC3_INVALID_CHARGER;
}
dev_dbg(phy->dev, "No device, trying to suspend\n");
pm_runtime_put_sync(phy->dev);
}
break;
case OTG_STATE_B_PERIPHERAL:
if (!test_bit(B_SESS_VLD, &dotg->inputs) ||
!test_bit(ID, &dotg->inputs)) {
dev_dbg(phy->dev, "!id || !bsv\n");
dwc3_otg_start_peripheral(&dotg->otg, 0);
phy->state = OTG_STATE_B_IDLE;
if (charger)
charger->chg_type = DWC3_INVALID_CHARGER;
work = 1;
}
break;
case OTG_STATE_A_IDLE:
/* Switch to A-Device*/
if (test_bit(ID, &dotg->inputs)) {
dev_dbg(phy->dev, "id\n");
phy->state = OTG_STATE_B_IDLE;
work = 1;
} else {
if (dwc3_otg_start_host(&dotg->otg, 1)) {
/*
* Probably set_host was not called yet.
* We will re-try as soon as it will be called
*/
dev_dbg(phy->dev, "enter lpm as\n"
"unable to start A-device\n");
phy->state = OTG_STATE_UNDEFINED;
pm_runtime_put_sync(phy->dev);
return;
}
phy->state = OTG_STATE_A_HOST;
}
break;
case OTG_STATE_A_HOST:
if (test_bit(ID, &dotg->inputs)) {
dev_dbg(phy->dev, "id\n");
dwc3_otg_start_host(&dotg->otg, 0);
phy->state = OTG_STATE_B_IDLE;
work = 1;
}
break;
default:
dev_err(phy->dev, "%s: invalid otg-state\n", __func__);
}
if (work)
schedule_work(&dotg->sm_work);
}
/**
* dwc3_otg_reset - reset dwc3 otg registers.
*
* @w: Pointer to the dwc3 otg workqueue
*/
static void dwc3_otg_reset(struct dwc3_otg *dotg)
{
/*
* OCFG[2] - OTG-Version = 1
* OCFG[1] - HNPCap = 0
* OCFG[0] - SRPCap = 0
*/
dwc3_writel(dotg->regs, DWC3_OCFG, 0x4);
/*
* OCTL[6] - PeriMode = 1
* OCTL[5] - PrtPwrCtl = 0
* OCTL[4] - HNPReq = 0
* OCTL[3] - SesReq = 0
* OCTL[2] - TermSelDLPulse = 0
* OCTL[1] - DevSetHNPEn = 0
* OCTL[0] - HstSetHNPEn = 0
*/
dwc3_writel(dotg->regs, DWC3_OCTL, 0x40);
/* Clear all otg events (interrupts) indications */
dwc3_writel(dotg->regs, DWC3_OEVT, 0xFFFF);
/* Enable ID/BSV StsChngEn event*/
dwc3_writel(dotg->regs, DWC3_OEVTEN,
DWC3_OEVTEN_OTGCONIDSTSCHNGEVNT |
DWC3_OEVTEN_OTGBDEVVBUSCHNGEVNT);
}
/**
* dwc3_otg_init - Initializes otg related registers
* @dwc: Pointer to out controller context structure
*
* Returns 0 on success otherwise negative errno.
*/
int dwc3_otg_init(struct dwc3 *dwc)
{
u32 reg;
int ret = 0;
struct dwc3_otg *dotg;
dev_dbg(dwc->dev, "dwc3_otg_init\n");
/*
* GHWPARAMS6[10] bit is SRPSupport.
* This bit also reflects DWC_USB3_EN_OTG
*/
reg = dwc3_readl(dwc->regs, DWC3_GHWPARAMS6);
if (!(reg & DWC3_GHWPARAMS6_SRP_SUPPORT)) {
/*
* No OTG support in the HW core.
* We return 0 to indicate no error, since this is acceptable
* situation, just continue probe the dwc3 driver without otg.
*/
dev_dbg(dwc->dev, "dwc3_otg address space is not supported\n");
return 0;
}
/* Allocate and init otg instance */
dotg = kzalloc(sizeof(struct dwc3_otg), GFP_KERNEL);
if (!dotg) {
dev_err(dwc->dev, "unable to allocate dwc3_otg\n");
return -ENOMEM;
}
/* DWC3 has separate IRQ line for OTG events (ID/BSV etc.) */
dotg->irq = platform_get_irq_byname(to_platform_device(dwc->dev),
"otg_irq");
if (dotg->irq < 0) {
dev_err(dwc->dev, "%s: missing OTG IRQ\n", __func__);
ret = -ENODEV;
goto err1;
}
dotg->regs = dwc->regs;
dotg->otg.set_peripheral = dwc3_otg_set_peripheral;
dotg->otg.set_host = dwc3_otg_set_host;
/* This reference is used by dwc3 modules for checking otg existance */
dwc->dotg = dotg;
dotg->otg.phy = kzalloc(sizeof(struct usb_phy), GFP_KERNEL);
if (!dotg->otg.phy) {
dev_err(dwc->dev, "unable to allocate dwc3_otg.phy\n");
ret = -ENOMEM;
goto err1;
}
dotg->otg.phy->otg = &dotg->otg;
dotg->otg.phy->dev = dwc->dev;
ret = usb_set_transceiver(dotg->otg.phy);
if (ret) {
dev_err(dotg->otg.phy->dev,
"%s: failed to set transceiver, already exists\n",
__func__);
goto err2;
}
dwc3_otg_reset(dotg);
dotg->otg.phy->state = OTG_STATE_UNDEFINED;
INIT_WORK(&dotg->sm_work, dwc3_otg_sm_work);
ret = request_irq(dotg->irq, dwc3_otg_interrupt, IRQF_SHARED,
"dwc3_otg", dotg);
if (ret) {
dev_err(dotg->otg.phy->dev, "failed to request irq #%d --> %d\n",
dotg->irq, ret);
goto err3;
}
pm_runtime_get(dwc->dev);
return 0;
err3:
cancel_work_sync(&dotg->sm_work);
usb_set_transceiver(NULL);
err2:
kfree(dotg->otg.phy);
err1:
dwc->dotg = NULL;
kfree(dotg);
return ret;
}
/**
* dwc3_otg_exit
* @dwc: Pointer to out controller context structure
*
* Returns 0 on success otherwise negative errno.
*/
void dwc3_otg_exit(struct dwc3 *dwc)
{
struct dwc3_otg *dotg = dwc->dotg;
/* dotg is null when GHWPARAMS6[10]=SRPSupport=0, see dwc3_otg_init */
if (dotg) {
if (dotg->charger)
dotg->charger->start_detection(dotg->charger, false);
cancel_work_sync(&dotg->sm_work);
usb_set_transceiver(NULL);
pm_runtime_put(dwc->dev);
free_irq(dotg->irq, dotg);
kfree(dotg->otg.phy);
kfree(dotg);
dwc->dotg = NULL;
}
}