Re: [PATCH v6 07/12] usb: otg: add OTG/dual-role core
From: Peter Chen
Date: Thu Apr 21 2016 - 03:00:20 EST
On Tue, Apr 05, 2016 at 05:05:12PM +0300, Roger Quadros wrote:
> It provides APIs for the following tasks
>
> - Registering an OTG/dual-role capable controller
> - Registering Host and Gadget controllers to OTG core
> - Providing inputs to and kicking the OTG state machine
>
> Provide a dual-role device (DRD) state machine.
> DRD mode is a reduced functionality OTG mode. In this mode
> we don't support SRP, HNP and dynamic role-swap.
>
> In DRD operation, the controller mode (Host or Peripheral)
> is decided based on the ID pin status. Once a cable plug (Type-A
> or Type-B) is attached the controller selects the state
> and doesn't change till the cable in unplugged and a different
> cable type is inserted.
>
> As we don't need most of the complex OTG states and OTG timers
> we implement a lean DRD state machine in usb-otg.c.
> The DRD state machine is only interested in 2 hardware inputs
> 'id' and 'b_sess_vld'.
>
> Signed-off-by: Roger Quadros <rogerq@xxxxxx>
> ---
> drivers/usb/common/Makefile | 2 +-
> drivers/usb/common/usb-otg.c | 1058 ++++++++++++++++++++++++++++++++++++++++++
> drivers/usb/common/usb-otg.h | 71 +++
> drivers/usb/core/Kconfig | 2 +-
> include/linux/usb/gadget.h | 2 +
> include/linux/usb/hcd.h | 1 +
> include/linux/usb/otg-fsm.h | 7 +
> include/linux/usb/otg.h | 154 +++++-
> 8 files changed, 1292 insertions(+), 5 deletions(-)
> create mode 100644 drivers/usb/common/usb-otg.c
> create mode 100644 drivers/usb/common/usb-otg.h
>
> diff --git a/drivers/usb/common/Makefile b/drivers/usb/common/Makefile
> index f8f2c88..730d928 100644
> --- a/drivers/usb/common/Makefile
> +++ b/drivers/usb/common/Makefile
> @@ -7,5 +7,5 @@ usb-common-y += common.o
> usb-common-$(CONFIG_USB_LED_TRIG) += led.o
>
> obj-$(CONFIG_USB_ULPI_BUS) += ulpi.o
> -usbotg-y := usb-otg-fsm.o
> +usbotg-y := usb-otg.o usb-otg-fsm.o
> obj-$(CONFIG_USB_OTG) += usbotg.o
> diff --git a/drivers/usb/common/usb-otg.c b/drivers/usb/common/usb-otg.c
> new file mode 100644
> index 0000000..41e762a
> --- /dev/null
> +++ b/drivers/usb/common/usb-otg.c
> @@ -0,0 +1,1058 @@
> +/**
> + * drivers/usb/common/usb-otg.c - USB OTG core
> + *
> + * Copyright (C) 2016 Texas Instruments Incorporated - http://www.ti.com
> + * Author: Roger Quadros <rogerq@xxxxxx>
> + *
> + * This program is free software; you can redistribute it and/or modify
> + * it under the terms of the GNU General Public License 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/kernel.h>
> +#include <linux/ktime.h>
> +#include <linux/hrtimer.h>
> +#include <linux/list.h>
> +#include <linux/of.h>
> +#include <linux/of_platform.h>
> +#include <linux/usb/otg.h>
> +#include <linux/usb/gadget.h>
> +#include <linux/workqueue.h>
> +
> +#include "usb-otg.h"
> +
> +struct otg_gcd {
> + struct usb_gadget *gadget;
> + struct otg_gadget_ops *ops;
> +};
> +
> +/* OTG device list */
> +LIST_HEAD(otg_list);
> +static DEFINE_MUTEX(otg_list_mutex);
> +
> +/* Hosts and Gadgets waiting for OTG controller */
> +struct otg_wait_data {
> + struct device *dev; /* OTG controller device */
> +
> + struct otg_hcd primary_hcd;
> + struct otg_hcd shared_hcd;
> + struct otg_gcd gcd;
> + struct list_head list;
> +};
> +
> +LIST_HEAD(wait_list);
> +static DEFINE_MUTEX(wait_list_mutex);
> +
> +static int usb_otg_hcd_is_primary_hcd(struct usb_hcd *hcd)
> +{
> + if (!hcd->primary_hcd)
> + return 1;
> + return hcd == hcd->primary_hcd;
> +}
Just find there is already a usb_hcd_is_primary_hcd at hcd.c,
would you use it directly?
Peter
> +
> +/**
> + * Check if the OTG device is in our wait list and return
> + * otg_wait_data, else NULL.
> + *
> + * wait_list_mutex must be held.
> + */
> +static struct otg_wait_data *usb_otg_get_wait(struct device *otg_dev)
> +{
> + struct otg_wait_data *wait;
> +
> + if (!otg_dev)
> + return NULL;
> +
> + /* is there an entry for this otg_dev ?*/
> + list_for_each_entry(wait, &wait_list, list) {
> + if (wait->dev == otg_dev)
> + return wait;
> + }
> +
> + return NULL;
> +}
> +
> +/**
> + * Add the hcd to our wait list
> + */
> +static int usb_otg_hcd_wait_add(struct device *otg_dev, struct usb_hcd *hcd,
> + unsigned int irqnum, unsigned long irqflags,
> + struct otg_hcd_ops *ops)
> +{
> + struct otg_wait_data *wait;
> + int ret = -EINVAL;
> +
> + mutex_lock(&wait_list_mutex);
> +
> + wait = usb_otg_get_wait(otg_dev);
> + if (!wait) {
> + /* Not yet in wait list? allocate and add */
> + wait = kzalloc(sizeof(*wait), GFP_KERNEL);
> + if (!wait) {
> + ret = -ENOMEM;
> + goto fail;
> + }
> +
> + wait->dev = otg_dev;
> + list_add_tail(&wait->list, &wait_list);
> + }
> +
> + if (usb_otg_hcd_is_primary_hcd(hcd)) {
> + if (wait->primary_hcd.hcd) /* already assigned? */
> + goto fail;
> +
> + wait->primary_hcd.hcd = hcd;
> + wait->primary_hcd.irqnum = irqnum;
> + wait->primary_hcd.irqflags = irqflags;
> + wait->primary_hcd.ops = ops;
> + wait->primary_hcd.otg_dev = otg_dev;
> + } else {
> + if (wait->shared_hcd.hcd) /* already assigned? */
> + goto fail;
> +
> + wait->shared_hcd.hcd = hcd;
> + wait->shared_hcd.irqnum = irqnum;
> + wait->shared_hcd.irqflags = irqflags;
> + wait->shared_hcd.ops = ops;
> + wait->shared_hcd.otg_dev = otg_dev;
> + }
> +
> + mutex_unlock(&wait_list_mutex);
> + return 0;
> +
> +fail:
> + mutex_unlock(&wait_list_mutex);
> + return ret;
> +}
> +
> +/**
> + * Check and free wait list entry if empty
> + *
> + * wait_list_mutex must be held
> + */
> +static void usb_otg_check_free_wait(struct otg_wait_data *wait)
> +{
> + if (wait->primary_hcd.hcd || wait->shared_hcd.hcd || wait->gcd.gadget)
> + return;
> +
> + list_del(&wait->list);
> + kfree(wait);
> +}
> +
> +/**
> + * Remove the hcd from our wait list
> + */
> +static int usb_otg_hcd_wait_remove(struct usb_hcd *hcd)
> +{
> + struct otg_wait_data *wait;
> +
> + mutex_lock(&wait_list_mutex);
> +
> + /* is there an entry for this hcd ?*/
> + list_for_each_entry(wait, &wait_list, list) {
> + if (wait->primary_hcd.hcd == hcd) {
> + wait->primary_hcd.hcd = 0;
> + goto found;
> + } else if (wait->shared_hcd.hcd == hcd) {
> + wait->shared_hcd.hcd = 0;
> + goto found;
> + }
> + }
> +
> + mutex_unlock(&wait_list_mutex);
> + return -EINVAL;
> +
> +found:
> + usb_otg_check_free_wait(wait);
> + mutex_unlock(&wait_list_mutex);
> +
> + return 0;
> +}
> +
> +/**
> + * Add the gadget to our wait list
> + */
> +static int usb_otg_gadget_wait_add(struct device *otg_dev,
> + struct usb_gadget *gadget,
> + struct otg_gadget_ops *ops)
> +{
> + struct otg_wait_data *wait;
> + int ret = -EINVAL;
> +
> + mutex_lock(&wait_list_mutex);
> +
> + wait = usb_otg_get_wait(otg_dev);
> + if (!wait) {
> + /* Not yet in wait list? allocate and add */
> + wait = kzalloc(sizeof(*wait), GFP_KERNEL);
> + if (!wait) {
> + ret = -ENOMEM;
> + goto fail;
> + }
> +
> + wait->dev = otg_dev;
> + list_add_tail(&wait->list, &wait_list);
> + }
> +
> + if (wait->gcd.gadget) /* already assigned? */
> + goto fail;
> +
> + wait->gcd.gadget = gadget;
> + wait->gcd.ops = ops;
> + mutex_unlock(&wait_list_mutex);
> +
> + return 0;
> +
> +fail:
> + mutex_unlock(&wait_list_mutex);
> + return ret;
> +}
> +
> +/**
> + * Remove the gadget from our wait list
> + */
> +static int usb_otg_gadget_wait_remove(struct usb_gadget *gadget)
> +{
> + struct otg_wait_data *wait;
> +
> + mutex_lock(&wait_list_mutex);
> +
> + /* is there an entry for this gadget ?*/
> + list_for_each_entry(wait, &wait_list, list) {
> + if (wait->gcd.gadget == gadget) {
> + wait->gcd.gadget = 0;
> + goto found;
> + }
> + }
> +
> + mutex_unlock(&wait_list_mutex);
> +
> + return -EINVAL;
> +
> +found:
> + usb_otg_check_free_wait(wait);
> + mutex_unlock(&wait_list_mutex);
> +
> + return 0;
> +}
> +
> +/**
> + * Register pending host/gadget and remove entry from wait list
> + */
> +static void usb_otg_flush_wait(struct device *otg_dev)
> +{
> + struct otg_wait_data *wait;
> + struct otg_hcd *host;
> + struct otg_gcd *gadget;
> +
> + mutex_lock(&wait_list_mutex);
> +
> + wait = usb_otg_get_wait(otg_dev);
> + if (!wait)
> + goto done;
> +
> + dev_dbg(otg_dev, "otg: registering pending host/gadget\n");
> + gadget = &wait->gcd;
> + if (gadget)
> + usb_otg_register_gadget(gadget->gadget, gadget->ops);
> +
> + host = &wait->primary_hcd;
> + if (host->hcd)
> + usb_otg_register_hcd(host->hcd, host->irqnum, host->irqflags,
> + host->ops);
> +
> + host = &wait->shared_hcd;
> + if (host->hcd)
> + usb_otg_register_hcd(host->hcd, host->irqnum, host->irqflags,
> + host->ops);
> +
> + list_del(&wait->list);
> + kfree(wait);
> +
> +done:
> + mutex_unlock(&wait_list_mutex);
> +}
> +
> +/**
> + * Check if the OTG device is in our OTG list and return
> + * usb_otg data, else NULL.
> + *
> + * otg_list_mutex must be held.
> + */
> +static struct usb_otg *usb_otg_get_data(struct device *otg_dev)
> +{
> + struct usb_otg *otg;
> +
> + if (!otg_dev)
> + return NULL;
> +
> + list_for_each_entry(otg, &otg_list, list) {
> + if (otg->dev == otg_dev)
> + return otg;
> + }
> +
> + return NULL;
> +}
> +
> +/**
> + * usb_otg_start_host - start/stop the host controller
> + * @otg: usb_otg instance
> + * @on: true to start, false to stop
> + *
> + * Start/stop the USB host controller. This function is meant
> + * for use by the OTG controller driver.
> + */
> +int usb_otg_start_host(struct usb_otg *otg, int on)
> +{
> + struct otg_hcd_ops *hcd_ops = otg->hcd_ops;
> +
> + dev_dbg(otg->dev, "otg: %s %d\n", __func__, on);
> + if (!otg->host) {
> + WARN_ONCE(1, "otg: fsm running without host\n");
> + return 0;
> + }
> +
> + if (on) {
> + if (otg->flags & OTG_FLAG_HOST_RUNNING)
> + return 0;
> +
> + otg->flags |= OTG_FLAG_HOST_RUNNING;
> +
> + /* start host */
> + hcd_ops->add(otg->primary_hcd.hcd, otg->primary_hcd.irqnum,
> + otg->primary_hcd.irqflags);
> + if (otg->shared_hcd.hcd) {
> + hcd_ops->add(otg->shared_hcd.hcd,
> + otg->shared_hcd.irqnum,
> + otg->shared_hcd.irqflags);
> + }
> + } else {
> + if (!(otg->flags & OTG_FLAG_HOST_RUNNING))
> + return 0;
> +
> + otg->flags &= ~OTG_FLAG_HOST_RUNNING;
> +
> + /* stop host */
> + if (otg->shared_hcd.hcd)
> + hcd_ops->remove(otg->shared_hcd.hcd);
> +
> + hcd_ops->remove(otg->primary_hcd.hcd);
> + }
> +
> + return 0;
> +}
> +EXPORT_SYMBOL_GPL(usb_otg_start_host);
> +
> +/**
> + * usb_otg_start_gadget - start/stop the gadget controller
> + * @otg: usb_otg instance
> + * @on: true to start, false to stop
> + *
> + * Start/stop the USB gadget controller. This function is meant
> + * for use by the OTG controller driver.
> + */
> +int usb_otg_start_gadget(struct usb_otg *otg, int on)
> +{
> + struct usb_gadget *gadget = otg->gadget;
> +
> + dev_dbg(otg->dev, "otg: %s %d\n", __func__, on);
> + if (!gadget) {
> + WARN_ONCE(1, "otg: fsm running without gadget\n");
> + return 0;
> + }
> +
> + if (on) {
> + if (otg->flags & OTG_FLAG_GADGET_RUNNING)
> + return 0;
> +
> + otg->flags |= OTG_FLAG_GADGET_RUNNING;
> + otg->gadget_ops->start(otg->gadget);
> + } else {
> + if (!(otg->flags & OTG_FLAG_GADGET_RUNNING))
> + return 0;
> +
> + otg->flags &= ~OTG_FLAG_GADGET_RUNNING;
> + otg->gadget_ops->stop(otg->gadget);
> + }
> +
> + return 0;
> +}
> +EXPORT_SYMBOL_GPL(usb_otg_start_gadget);
> +
> +/**
> + * Change USB protocol when there is a protocol change.
> + * fsm->lock must be held.
> + */
> +static int drd_set_protocol(struct otg_fsm *fsm, int protocol)
> +{
> + struct usb_otg *otg = container_of(fsm, struct usb_otg, fsm);
> + int ret = 0;
> +
> + if (fsm->protocol != protocol) {
> + dev_dbg(otg->dev, "otg: changing role fsm->protocol= %d; new protocol= %d\n",
> + fsm->protocol, protocol);
> + /* stop old protocol */
> + if (fsm->protocol == PROTO_HOST)
> + ret = otg_start_host(otg, 0);
> + else if (fsm->protocol == PROTO_GADGET)
> + ret = otg_start_gadget(otg, 0);
> + if (ret)
> + return ret;
> +
> + /* start new protocol */
> + if (protocol == PROTO_HOST)
> + ret = otg_start_host(otg, 1);
> + else if (protocol == PROTO_GADGET)
> + ret = otg_start_gadget(otg, 1);
> + if (ret)
> + return ret;
> +
> + fsm->protocol = protocol;
> + return 0;
> + }
> +
> + return 0;
> +}
> +
> +/**
> + * Called when entering a DRD state.
> + * fsm->lock must be held.
> + */
> +static void drd_set_state(struct otg_fsm *fsm, enum usb_otg_state new_state)
> +{
> + struct usb_otg *otg = container_of(fsm, struct usb_otg, fsm);
> +
> + if (otg->state == new_state)
> + return;
> +
> + fsm->state_changed = 1;
> + dev_dbg(otg->dev, "otg: set state: %s\n",
> + usb_otg_state_string(new_state));
> + switch (new_state) {
> + case OTG_STATE_B_IDLE:
> + drd_set_protocol(fsm, PROTO_UNDEF);
> + otg_drv_vbus(otg, 0);
> + break;
> + case OTG_STATE_B_PERIPHERAL:
> + drd_set_protocol(fsm, PROTO_GADGET);
> + otg_drv_vbus(otg, 0);
> + break;
> + case OTG_STATE_A_HOST:
> + drd_set_protocol(fsm, PROTO_HOST);
> + otg_drv_vbus(otg, 1);
> + break;
> + case OTG_STATE_UNDEFINED:
> + case OTG_STATE_B_SRP_INIT:
> + case OTG_STATE_B_WAIT_ACON:
> + case OTG_STATE_B_HOST:
> + case OTG_STATE_A_IDLE:
> + case OTG_STATE_A_WAIT_VRISE:
> + case OTG_STATE_A_WAIT_BCON:
> + case OTG_STATE_A_SUSPEND:
> + case OTG_STATE_A_PERIPHERAL:
> + case OTG_STATE_A_WAIT_VFALL:
> + case OTG_STATE_A_VBUS_ERR:
> + default:
> + dev_warn(otg->dev, "%s: otg: invalid state: %s\n",
> + __func__, usb_otg_state_string(new_state));
> + break;
> + }
> +
> + otg->state = new_state;
> +}
> +
> +/**
> + * DRD state change judgement
> + *
> + * For DRD we're only interested in some of the OTG states
> + * i.e. OTG_STATE_B_IDLE: both peripheral and host are stopped
> + * OTG_STATE_B_PERIPHERAL: peripheral active
> + * OTG_STATE_A_HOST: host active
> + * we're only interested in the following inputs
> + * fsm->id, fsm->b_sess_vld
> + */
> +int drd_statemachine(struct usb_otg *otg)
> +{
> + struct otg_fsm *fsm = &otg->fsm;
> + enum usb_otg_state state;
> + int ret;
> +
> + mutex_lock(&fsm->lock);
> +
> + fsm->state_changed = 0;
> + state = otg->state;
> +
> + switch (state) {
> + case OTG_STATE_UNDEFINED:
> + if (!fsm->id)
> + drd_set_state(fsm, OTG_STATE_A_HOST);
> + else if (fsm->id && fsm->b_sess_vld)
> + drd_set_state(fsm, OTG_STATE_B_PERIPHERAL);
> + else
> + drd_set_state(fsm, OTG_STATE_B_IDLE);
> + break;
> + case OTG_STATE_B_IDLE:
> + if (!fsm->id)
> + drd_set_state(fsm, OTG_STATE_A_HOST);
> + else if (fsm->b_sess_vld)
> + drd_set_state(fsm, OTG_STATE_B_PERIPHERAL);
> + break;
> + case OTG_STATE_B_PERIPHERAL:
> + if (!fsm->id)
> + drd_set_state(fsm, OTG_STATE_A_HOST);
> + else if (!fsm->b_sess_vld)
> + drd_set_state(fsm, OTG_STATE_B_IDLE);
> + break;
> + case OTG_STATE_A_HOST:
> + if (fsm->id && fsm->b_sess_vld)
> + drd_set_state(fsm, OTG_STATE_B_PERIPHERAL);
> + else if (fsm->id && !fsm->b_sess_vld)
> + drd_set_state(fsm, OTG_STATE_B_IDLE);
> + break;
> +
> + /* invalid states for DRD */
> + case OTG_STATE_B_SRP_INIT:
> + case OTG_STATE_B_WAIT_ACON:
> + case OTG_STATE_B_HOST:
> + case OTG_STATE_A_IDLE:
> + case OTG_STATE_A_WAIT_VRISE:
> + case OTG_STATE_A_WAIT_BCON:
> + case OTG_STATE_A_SUSPEND:
> + case OTG_STATE_A_PERIPHERAL:
> + case OTG_STATE_A_WAIT_VFALL:
> + case OTG_STATE_A_VBUS_ERR:
> + dev_err(otg->dev, "%s: otg: invalid usb-drd state: %s\n",
> + __func__, usb_otg_state_string(state));
> + drd_set_state(fsm, OTG_STATE_UNDEFINED);
> + break;
> + }
> +
> + ret = fsm->state_changed;
> + mutex_unlock(&fsm->lock);
> + dev_dbg(otg->dev, "otg: quit statemachine, changed %d\n",
> + fsm->state_changed);
> +
> + return ret;
> +}
> +EXPORT_SYMBOL_GPL(drd_statemachine);
> +
> +/**
> + * OTG FSM/DRD work function
> + */
> +static void usb_otg_work(struct work_struct *work)
> +{
> + struct usb_otg *otg = container_of(work, struct usb_otg, work);
> +
> + pm_runtime_get_sync(otg->dev);
> + drd_statemachine(otg);
> + pm_runtime_put_sync(otg->dev);
> +}
> +
> +/**
> + * usb_otg_register() - Register the OTG/dual-role device to OTG core
> + * @dev: OTG/dual-role controller device.
> + * @config: OTG configuration.
> + *
> + * Registers the OTG/dual-role controller device with the USB OTG core.
> + *
> + * Return: struct usb_otg * if success, ERR_PTR() if error.
> + */
> +struct usb_otg *usb_otg_register(struct device *dev,
> + struct usb_otg_config *config)
> +{
> + struct usb_otg *otg;
> + struct otg_wait_data *wait;
> + int ret = 0;
> +
> + if (!dev || !config || !config->fsm_ops)
> + return ERR_PTR(-EINVAL);
> +
> + /* already in list? */
> + mutex_lock(&otg_list_mutex);
> + if (usb_otg_get_data(dev)) {
> + dev_err(dev, "otg: %s: device already in otg list\n",
> + __func__);
> + ret = -EINVAL;
> + goto unlock;
> + }
> +
> + /* allocate and add to list */
> + otg = kzalloc(sizeof(*otg), GFP_KERNEL);
> + if (!otg) {
> + ret = -ENOMEM;
> + goto unlock;
> + }
> +
> + otg->dev = dev;
> + otg->caps = config->otg_caps;
> +
> + if ((otg->caps->hnp_support || otg->caps->srp_support ||
> + otg->caps->adp_support) && !config->otg_work)
> + dev_info(dev, "otg: limiting to dual-role\n");
> +
> + if (config->otg_work) /* custom otg_work ? */
> + INIT_WORK(&otg->work, config->otg_work);
> + else
> + INIT_WORK(&otg->work, usb_otg_work);
> +
> + otg->wq = create_singlethread_workqueue("usb_otg");
> + if (!otg->wq) {
> + dev_err(dev, "otg: %s: can't create workqueue\n",
> + __func__);
> + ret = -ENOMEM;
> + goto err_wq;
> + }
> +
> + /* set otg ops */
> + otg->fsm.ops = config->fsm_ops;
> +
> + mutex_init(&otg->fsm.lock);
> +
> + list_add_tail(&otg->list, &otg_list);
> + mutex_unlock(&otg_list_mutex);
> +
> + /* were we in wait list? */
> + mutex_lock(&wait_list_mutex);
> + wait = usb_otg_get_wait(dev);
> + mutex_unlock(&wait_list_mutex);
> + if (wait) {
> + /* register pending host/gadget and flush from list */
> + usb_otg_flush_wait(dev);
> + }
> +
> + return otg;
> +
> +err_wq:
> + kfree(otg);
> +unlock:
> + mutex_unlock(&otg_list_mutex);
> + return ERR_PTR(ret);
> +}
> +EXPORT_SYMBOL_GPL(usb_otg_register);
> +
> +/**
> + * usb_otg_unregister() - Unregister the OTG/dual-role device from USB OTG core
> + * @dev: OTG controller device.
> + *
> + * Unregisters the OTG/dual-role controller device from USB OTG core.
> + * Prevents unregistering till both the associated Host and Gadget controllers
> + * have unregistered from the OTG core.
> + *
> + * Return: 0 on success, error value otherwise.
> + */
> +int usb_otg_unregister(struct device *dev)
> +{
> + struct usb_otg *otg;
> +
> + mutex_lock(&otg_list_mutex);
> + otg = usb_otg_get_data(dev);
> + if (!otg) {
> + dev_err(dev, "otg: %s: device not in otg list\n",
> + __func__);
> + mutex_unlock(&otg_list_mutex);
> + return -EINVAL;
> + }
> +
> + /* prevent unregister till both host & gadget have unregistered */
> + if (otg->host || otg->gadget) {
> + dev_err(dev, "otg: %s: host/gadget still registered\n",
> + __func__);
> + return -EBUSY;
> + }
> +
> + /* OTG FSM is halted when host/gadget unregistered */
> + destroy_workqueue(otg->wq);
> +
> + /* remove from otg list */
> + list_del(&otg->list);
> + kfree(otg);
> + mutex_unlock(&otg_list_mutex);
> +
> + return 0;
> +}
> +EXPORT_SYMBOL_GPL(usb_otg_unregister);
> +
> +/**
> + * start/kick the OTG FSM if we can
> + * fsm->lock must be held
> + */
> +static void usb_otg_start_fsm(struct usb_otg *otg)
> +{
> + struct otg_fsm *fsm = &otg->fsm;
> +
> + if (fsm->running)
> + goto kick_fsm;
> +
> + if (!otg->host) {
> + dev_info(otg->dev, "otg: can't start till host registers\n");
> + return;
> + }
> +
> + if (!otg->gadget) {
> + dev_info(otg->dev, "otg: can't start till gadget registers\n");
> + return;
> + }
> +
> + fsm->running = true;
> +kick_fsm:
> + queue_work(otg->wq, &otg->work);
> +}
> +
> +/**
> + * stop the OTG FSM. Stops Host & Gadget controllers as well.
> + * fsm->lock must be held
> + */
> +static void usb_otg_stop_fsm(struct usb_otg *otg)
> +{
> + struct otg_fsm *fsm = &otg->fsm;
> +
> + if (!fsm->running)
> + return;
> +
> + /* no more new events queued */
> + fsm->running = false;
> +
> + flush_workqueue(otg->wq);
> + otg->state = OTG_STATE_UNDEFINED;
> +
> + /* stop host/gadget immediately */
> + if (fsm->protocol == PROTO_HOST)
> + otg_start_host(otg, 0);
> + else if (fsm->protocol == PROTO_GADGET)
> + otg_start_gadget(otg, 0);
> + fsm->protocol = PROTO_UNDEF;
> +}
> +
> +/**
> + * usb_otg_sync_inputs - Sync OTG inputs with the OTG state machine
> + * @fsm: OTG FSM instance
> + *
> + * Used by the OTG driver to update the inputs to the OTG
> + * state machine.
> + *
> + * Can be called in IRQ context.
> + */
> +void usb_otg_sync_inputs(struct usb_otg *otg)
> +{
> + /* Don't kick FSM till it has started */
> + if (!otg->fsm.running)
> + return;
> +
> + /* Kick FSM */
> + queue_work(otg->wq, &otg->work);
> +}
> +EXPORT_SYMBOL_GPL(usb_otg_sync_inputs);
> +
> +/**
> + * usb_otg_kick_fsm - Kick the OTG state machine
> + * @otg_dev: OTG controller device
> + *
> + * Used by USB host/device stack to sync OTG related
> + * events to the OTG state machine.
> + * e.g. change in host_bus->b_hnp_enable, gadget->b_hnp_enable
> + *
> + * Returns: 0 on success, error value otherwise.
> + */
> +int usb_otg_kick_fsm(struct device *otg_dev)
> +{
> + struct usb_otg *otg;
> +
> + mutex_lock(&otg_list_mutex);
> + otg = usb_otg_get_data(otg_dev);
> + mutex_unlock(&otg_list_mutex);
> + if (!otg) {
> + dev_dbg(otg_dev, "otg: %s: invalid otg device\n",
> + __func__);
> + return -ENODEV;
> + }
> +
> + usb_otg_sync_inputs(otg);
> +
> + return 0;
> +}
> +EXPORT_SYMBOL_GPL(usb_otg_kick_fsm);
> +
> +/**
> + * usb_otg_register_hcd - Register the host controller to OTG core
> + * @hcd: host controller device
> + * @irqnum: interrupt number
> + * @irqflags: interrupt flags
> + * @ops: HCD ops to interface with the HCD
> + *
> + * This is used by the USB Host stack to register the host controller
> + * to the OTG core. Host controller must not be started by the
> + * caller as it is left upto the OTG state machine to do so.
> + * hcd->otg_dev must contain the related otg controller device.
> + *
> + * Returns: 0 on success, error value otherwise.
> + */
> +int usb_otg_register_hcd(struct usb_hcd *hcd, unsigned int irqnum,
> + unsigned long irqflags, struct otg_hcd_ops *ops)
> +{
> + struct usb_otg *otg;
> + struct device *hcd_dev = hcd->self.controller;
> + struct device *otg_dev = hcd->otg_dev;
> +
> + if (!otg_dev)
> + return -EINVAL;
> +
> + /* we're otg but otg controller might not yet be registered */
> + mutex_lock(&otg_list_mutex);
> + otg = usb_otg_get_data(otg_dev);
> + mutex_unlock(&otg_list_mutex);
> + if (!otg) {
> + dev_dbg(hcd_dev,
> + "otg: controller not yet registered. waiting..\n");
> + /*
> + * otg controller might register later. Put the hcd in
> + * wait list and call us back when ready
> + */
> + if (usb_otg_hcd_wait_add(otg_dev, hcd, irqnum, irqflags, ops)) {
> + dev_err(hcd_dev, "otg: failed to add hcd to wait list\n");
> + return -EINVAL;
> + }
> +
> + return 0;
> + }
> +
> + /* HCD will be started by OTG fsm when needed */
> + mutex_lock(&otg->fsm.lock);
> + if (otg->primary_hcd.hcd) {
> + /* probably a shared HCD ? */
> + if (usb_otg_hcd_is_primary_hcd(hcd)) {
> + dev_err(otg_dev, "otg: primary host already registered\n");
> + goto err;
> + }
> +
> + if (hcd->shared_hcd == otg->primary_hcd.hcd) {
> + if (otg->shared_hcd.hcd) {
> + dev_err(otg_dev, "otg: shared host already registered\n");
> + goto err;
> + }
> +
> + otg->shared_hcd.hcd = hcd;
> + otg->shared_hcd.irqnum = irqnum;
> + otg->shared_hcd.irqflags = irqflags;
> + otg->shared_hcd.ops = ops;
> + dev_info(otg_dev, "otg: shared host %s registered\n",
> + dev_name(hcd->self.controller));
> + } else {
> + dev_err(otg_dev, "otg: invalid shared host %s\n",
> + dev_name(hcd->self.controller));
> + goto err;
> + }
> + } else {
> + if (!usb_otg_hcd_is_primary_hcd(hcd)) {
> + dev_err(otg_dev, "otg: primary host must be registered first\n");
> + goto err;
> + }
> +
> + otg->primary_hcd.hcd = hcd;
> + otg->primary_hcd.irqnum = irqnum;
> + otg->primary_hcd.irqflags = irqflags;
> + otg->primary_hcd.ops = ops;
> + otg->hcd_ops = ops;
> + dev_info(otg_dev, "otg: primary host %s registered\n",
> + dev_name(hcd->self.controller));
> + }
> +
> + /*
> + * we're ready only if we have shared HCD
> + * or we don't need shared HCD.
> + */
> + if (otg->shared_hcd.hcd || !otg->primary_hcd.hcd->shared_hcd) {
> + otg->host = hcd_to_bus(hcd);
> + /* FIXME: set bus->otg_port if this is true OTG port with HNP */
> +
> + /* start FSM */
> + usb_otg_start_fsm(otg);
> + } else {
> + dev_dbg(otg_dev, "otg: can't start till shared host registers\n");
> + }
> +
> + mutex_unlock(&otg->fsm.lock);
> +
> + return 0;
> +
> +err:
> + mutex_unlock(&otg->fsm.lock);
> + return -EINVAL;
> +}
> +EXPORT_SYMBOL_GPL(usb_otg_register_hcd);
> +
> +/**
> + * usb_otg_unregister_hcd - Unregister the host controller from OTG core
> + * @hcd: host controller device
> + *
> + * This is used by the USB Host stack to unregister the host controller
> + * from the OTG core. Ensures that host controller is not running
> + * on successful return.
> + *
> + * Returns: 0 on success, error value otherwise.
> + */
> +int usb_otg_unregister_hcd(struct usb_hcd *hcd)
> +{
> + struct usb_otg *otg;
> + struct device *hcd_dev = hcd_to_bus(hcd)->controller;
> + struct device *otg_dev = hcd->otg_dev;
> +
> + if (!otg_dev)
> + return -EINVAL; /* we're definitely not OTG */
> +
> + mutex_lock(&otg_list_mutex);
> + otg = usb_otg_get_data(otg_dev);
> + mutex_unlock(&otg_list_mutex);
> + if (!otg) {
> + /* are we in wait list? */
> + if (!usb_otg_hcd_wait_remove(hcd))
> + return 0;
> +
> + dev_dbg(hcd_dev, "otg: host wasn't registered with otg\n");
> + return -EINVAL;
> + }
> +
> + mutex_lock(&otg->fsm.lock);
> + if (hcd == otg->primary_hcd.hcd) {
> + otg->primary_hcd.hcd = NULL;
> + dev_info(otg_dev, "otg: primary host %s unregistered\n",
> + dev_name(hcd_dev));
> + } else if (hcd == otg->shared_hcd.hcd) {
> + otg->shared_hcd.hcd = NULL;
> + dev_info(otg_dev, "otg: shared host %s unregistered\n",
> + dev_name(hcd_dev));
> + } else {
> + dev_err(otg_dev, "otg: host %s wasn't registered with otg\n",
> + dev_name(hcd_dev));
> + mutex_unlock(&otg->fsm.lock);
> + return -EINVAL;
> + }
> +
> + /* stop FSM & Host */
> + usb_otg_stop_fsm(otg);
> + otg->host = NULL;
> +
> + mutex_unlock(&otg->fsm.lock);
> +
> + return 0;
> +}
> +EXPORT_SYMBOL_GPL(usb_otg_unregister_hcd);
> +
> +/**
> + * usb_otg_register_gadget - Register the gadget controller to OTG core
> + * @gadget: gadget controller
> + *
> + * This is used by the USB gadget stack to register the gadget controller
> + * to the OTG core. Gadget controller must not be started by the
> + * caller as it is left upto the OTG state machine to do so.
> + *
> + * Gadget core must call this only when all resources required for
> + * gadget controller to run are available.
> + * i.e. gadget function driver is available.
> + *
> + * Returns: 0 on success, error value otherwise.
> + */
> +int usb_otg_register_gadget(struct usb_gadget *gadget,
> + struct otg_gadget_ops *ops)
> +{
> + struct usb_otg *otg;
> + struct device *gadget_dev = &gadget->dev;
> + struct device *otg_dev = gadget->otg_dev;
> +
> + if (!otg_dev)
> + return -EINVAL; /* we're definitely not OTG */
> +
> + /* we're otg but otg controller might not yet be registered */
> + mutex_lock(&otg_list_mutex);
> + otg = usb_otg_get_data(otg_dev);
> + mutex_unlock(&otg_list_mutex);
> + if (!otg) {
> + dev_dbg(gadget_dev,
> + "otg: controller not yet registered. waiting..\n");
> + /*
> + * otg controller might register later. Put the gadget in
> + * wait list and call us back when ready
> + */
> + if (usb_otg_gadget_wait_add(otg_dev, gadget, ops)) {
> + dev_err(gadget_dev,
> + "otg: failed to add to gadget to wait list\n");
> + return -EINVAL;
> + }
> +
> + return 0;
> + }
> +
> + mutex_lock(&otg->fsm.lock);
> + if (otg->gadget) {
> + dev_err(otg_dev, "otg: gadget already registered with otg\n");
> + mutex_unlock(&otg->fsm.lock);
> + return -EINVAL;
> + }
> +
> + otg->gadget = gadget;
> + otg->gadget_ops = ops;
> + dev_info(otg_dev, "otg: gadget %s registered\n",
> + dev_name(&gadget->dev));
> +
> + /* start FSM */
> + usb_otg_start_fsm(otg);
> + mutex_unlock(&otg->fsm.lock);
> +
> + return 0;
> +}
> +EXPORT_SYMBOL_GPL(usb_otg_register_gadget);
> +
> +/**
> + * usb_otg_unregister_gadget - Unregister the gadget controller from OTG core
> + * @gadget: gadget controller
> + *
> + * This is used by the USB gadget stack to unregister the gadget controller
> + * from the OTG core. Ensures that gadget controller is halted
> + * on successful return.
> + *
> + * Returns: 0 on success, error value otherwise.
> + */
> +int usb_otg_unregister_gadget(struct usb_gadget *gadget)
> +{
> + struct usb_otg *otg;
> + struct device *gadget_dev = &gadget->dev;
> + struct device *otg_dev = gadget->otg_dev;
> +
> + if (!otg_dev)
> + return -EINVAL;
> +
> + mutex_lock(&otg_list_mutex);
> + otg = usb_otg_get_data(otg_dev);
> + mutex_unlock(&otg_list_mutex);
> + if (!otg) {
> + /* are we in wait list? */
> + if (!usb_otg_gadget_wait_remove(gadget))
> + return 0;
> +
> + dev_dbg(gadget_dev, "otg: gadget wasn't registered with otg\n");
> + return -EINVAL;
> + }
> +
> + mutex_lock(&otg->fsm.lock);
> + if (otg->gadget != gadget) {
> + dev_err(otg_dev, "otg: gadget %s wasn't registered with otg\n",
> + dev_name(&gadget->dev));
> + mutex_unlock(&otg->fsm.lock);
> + return -EINVAL;
> + }
> +
> + /* Stop FSM & gadget */
> + usb_otg_stop_fsm(otg);
> + otg->gadget = NULL;
> + mutex_unlock(&otg->fsm.lock);
> +
> + dev_info(otg_dev, "otg: gadget %s unregistered\n",
> + dev_name(&gadget->dev));
> +
> + return 0;
> +}
> +EXPORT_SYMBOL_GPL(usb_otg_unregister_gadget);
> diff --git a/drivers/usb/common/usb-otg.h b/drivers/usb/common/usb-otg.h
> new file mode 100644
> index 0000000..2bf3fbf
> --- /dev/null
> +++ b/drivers/usb/common/usb-otg.h
> @@ -0,0 +1,71 @@
> +/**
> + * drivers/usb/common/usb-otg.h - USB OTG core local header
> + *
> + * Copyright (C) 2016 Texas Instruments Incorporated - http://www.ti.com
> + * Author: Roger Quadros <rogerq@xxxxxx>
> + *
> + * This program is free software; you can redistribute it and/or modify
> + * it under the terms of the GNU General Public License 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.
> + */
> +
> +#ifndef __DRIVERS_USB_COMMON_USB_OTG_H
> +#define __DRIVERS_USB_COMMON_USB_OTG_H
> +
> +/*
> + * A-DEVICE timing constants
> + */
> +
> +/* Wait for VBUS Rise */
> +#define TA_WAIT_VRISE (100) /* a_wait_vrise: section 7.1.2
> + * a_wait_vrise_tmr: section 7.4.5.1
> + * TA_VBUS_RISE <= 100ms, section 4.4
> + * Table 4-1: Electrical Characteristics
> + * ->DC Electrical Timing
> + */
> +/* Wait for VBUS Fall */
> +#define TA_WAIT_VFALL (1000) /* a_wait_vfall: section 7.1.7
> + * a_wait_vfall_tmr: section: 7.4.5.2
> + */
> +/* Wait for B-Connect */
> +#define TA_WAIT_BCON (10000) /* a_wait_bcon: section 7.1.3
> + * TA_WAIT_BCON: should be between 1100
> + * and 30000 ms, section 5.5, Table 5-1
> + */
> +/* A-Idle to B-Disconnect */
> +#define TA_AIDL_BDIS (5000) /* a_suspend min 200 ms, section 5.2.1
> + * TA_AIDL_BDIS: section 5.5, Table 5-1
> + */
> +/* B-Idle to A-Disconnect */
> +#define TA_BIDL_ADIS (500) /* TA_BIDL_ADIS: section 5.2.1
> + * 500ms is used for B switch to host
> + * for safe
> + */
> +
> +/*
> + * B-device timing constants
> + */
> +
> +/* Data-Line Pulse Time*/
> +#define TB_DATA_PLS (10) /* b_srp_init,continue 5~10ms
> + * section:5.1.3
> + */
> +/* SRP Fail Time */
> +#define TB_SRP_FAIL (6000) /* b_srp_init,fail time 5~6s
> + * section:5.1.6
> + */
> +/* A-SE0 to B-Reset */
> +#define TB_ASE0_BRST (155) /* minimum 155 ms, section:5.3.1 */
> +/* SE0 Time Before SRP */
> +#define TB_SE0_SRP (1000) /* b_idle,minimum 1s, section:5.1.2 */
> +/* SSEND time before SRP */
> +#define TB_SSEND_SRP (1500) /* minimum 1.5 sec, section:5.1.2 */
> +
> +#define TB_SESS_VLD (1000)
> +
> +#endif /* __DRIVERS_USB_COMMON_USB_OTG_H */
> diff --git a/drivers/usb/core/Kconfig b/drivers/usb/core/Kconfig
> index ae228d0..b468a9f 100644
> --- a/drivers/usb/core/Kconfig
> +++ b/drivers/usb/core/Kconfig
> @@ -42,7 +42,7 @@ config USB_DYNAMIC_MINORS
> If you are unsure about this, say N here.
>
> config USB_OTG
> - bool "OTG support"
> + bool "OTG/Dual-role support"
> depends on PM
> default n
> help
> diff --git a/include/linux/usb/gadget.h b/include/linux/usb/gadget.h
> index 8c0ae64..1878ae1 100644
> --- a/include/linux/usb/gadget.h
> +++ b/include/linux/usb/gadget.h
> @@ -583,6 +583,7 @@ struct usb_gadget_ops {
> * @out_epnum: last used out ep number
> * @in_epnum: last used in ep number
> * @otg_caps: OTG capabilities of this gadget.
> + * @otg_dev: OTG controller device, if needs to be used with OTG core.
> * @sg_supported: true if we can handle scatter-gather
> * @is_otg: True if the USB device port uses a Mini-AB jack, so that the
> * gadget driver must provide a USB OTG descriptor.
> @@ -639,6 +640,7 @@ struct usb_gadget {
> unsigned out_epnum;
> unsigned in_epnum;
> struct usb_otg_caps *otg_caps;
> + struct device *otg_dev;
>
> unsigned sg_supported:1;
> unsigned is_otg:1;
> diff --git a/include/linux/usb/hcd.h b/include/linux/usb/hcd.h
> index 861ccaa..2017cd4 100644
> --- a/include/linux/usb/hcd.h
> +++ b/include/linux/usb/hcd.h
> @@ -184,6 +184,7 @@ struct usb_hcd {
> struct mutex *bandwidth_mutex;
> struct usb_hcd *shared_hcd;
> struct usb_hcd *primary_hcd;
> + struct device *otg_dev; /* OTG controller device */
>
>
> #define HCD_BUFFER_POOLS 4
> diff --git a/include/linux/usb/otg-fsm.h b/include/linux/usb/otg-fsm.h
> index 36f0cf9..ba6755c 100644
> --- a/include/linux/usb/otg-fsm.h
> +++ b/include/linux/usb/otg-fsm.h
> @@ -61,6 +61,11 @@ enum otg_fsm_timer {
> /**
> * struct otg_fsm - OTG state machine according to the OTG spec
> *
> + * DRD mode hardware Inputs
> + *
> + * @id: TRUE for B-device, FALSE for A-device.
> + * @b_sess_vld: VBUS voltage in regulation.
> + *
> * OTG hardware Inputs
> *
> * Common inputs for A and B device
> @@ -133,6 +138,7 @@ enum otg_fsm_timer {
> * a_clr_err: Asserted (by application ?) to clear a_vbus_err due to an
> * overcurrent condition and causes the A-device to transition
> * to a_wait_vfall
> + * running: state machine running/stopped indicator
> */
> struct otg_fsm {
> /* Input */
> @@ -188,6 +194,7 @@ struct otg_fsm {
> int b_ase0_brst_tmout;
> int a_bidl_adis_tmout;
>
> + bool running;
> struct otg_fsm_ops *ops;
>
> /* Current usb protocol used: 0:undefine; 1:host; 2:client */
> diff --git a/include/linux/usb/otg.h b/include/linux/usb/otg.h
> index 85b8fb5..b094352 100644
> --- a/include/linux/usb/otg.h
> +++ b/include/linux/usb/otg.h
> @@ -10,10 +10,55 @@
> #define __LINUX_USB_OTG_H
>
> #include <linux/phy/phy.h>
> -#include <linux/usb/phy.h>
> -#include <linux/usb/otg-fsm.h>
> +#include <linux/device.h>
> +#include <linux/hrtimer.h>
> +#include <linux/ktime.h>
> +#include <linux/usb.h>
> #include <linux/usb/hcd.h>
> +#include <linux/usb/gadget.h>
> +#include <linux/usb/otg-fsm.h>
> +#include <linux/usb/phy.h>
>
> +/**
> + * struct otg_hcd - host controller state and interface
> + *
> + * @hcd: host controller
> + * @irqnum: irq number
> + * @irqflags: irq flags
> + * @ops: otg to host controller interface
> + * @ops: otg to host controller interface
> + * @otg_dev: otg controller device
> + */
> +struct otg_hcd {
> + struct usb_hcd *hcd;
> + unsigned int irqnum;
> + unsigned long irqflags;
> + struct otg_hcd_ops *ops;
> + struct device *otg_dev;
> +};
> +
> +/**
> + * struct usb_otg - usb otg controller state
> + *
> + * @default_a: Indicates we are an A device. i.e. Host.
> + * @phy: USB phy interface
> + * @usb_phy: old usb_phy interface
> + * @host: host controller bus
> + * @gadget: gadget device
> + * @state: current otg state
> + * @dev: otg controller device
> + * @caps: otg capabilities revision, hnp, srp, etc
> + * @fsm: otg finite state machine
> + * @hcd_ops: host controller interface
> + * ------- internal use only -------
> + * @primary_hcd: primary host state and interface
> + * @shared_hcd: shared host state and interface
> + * @gadget_ops: gadget controller interface
> + * @list: list of otg controllers
> + * @work: otg state machine work
> + * @wq: otg state machine work queue
> + * @flags: to track if host/gadget is running
> + */
> struct usb_otg {
> u8 default_a;
>
> @@ -24,9 +69,24 @@ struct usb_otg {
> struct usb_gadget *gadget;
>
> enum usb_otg_state state;
> + struct device *dev;
> + struct usb_otg_caps *caps;
> struct otg_fsm fsm;
> struct otg_hcd_ops *hcd_ops;
>
> + /* internal use only */
> + struct otg_hcd primary_hcd;
> + struct otg_hcd shared_hcd;
> + struct otg_gadget_ops *gadget_ops;
> + struct list_head list;
> + struct work_struct work;
> + struct workqueue_struct *wq;
> + u32 flags;
> +#define OTG_FLAG_GADGET_RUNNING (1 << 0)
> +#define OTG_FLAG_HOST_RUNNING (1 << 1)
> + /* use otg->fsm.lock for serializing access */
> +
> +/*------------- deprecated interface -----------------------------*/
> /* bind/unbind the host controller */
> int (*set_host)(struct usb_otg *otg, struct usb_bus *host);
>
> @@ -42,7 +102,7 @@ struct usb_otg {
>
> /* start or continue HNP role switch */
> int (*start_hnp)(struct usb_otg *otg);
> -
> +/*---------------------------------------------------------------*/
> };
>
> /**
> @@ -60,8 +120,92 @@ struct usb_otg_caps {
> bool adp_support;
> };
>
> +/**
> + * struct usb_otg_config - otg controller configuration
> + * @caps: otg capabilities of the controller
> + * @ops: otg fsm operations
> + * @otg_work: optional custom otg state machine work function
> + */
> +struct usb_otg_config {
> + struct usb_otg_caps *otg_caps;
> + struct otg_fsm_ops *fsm_ops;
> + void (*otg_work)(struct work_struct *work);
> +};
> +
> extern const char *usb_otg_state_string(enum usb_otg_state state);
>
> +#if IS_ENABLED(CONFIG_USB_OTG)
> +struct usb_otg *usb_otg_register(struct device *dev,
> + struct usb_otg_config *config);
> +int usb_otg_unregister(struct device *dev);
> +int usb_otg_register_hcd(struct usb_hcd *hcd, unsigned int irqnum,
> + unsigned long irqflags, struct otg_hcd_ops *ops);
> +int usb_otg_unregister_hcd(struct usb_hcd *hcd);
> +int usb_otg_register_gadget(struct usb_gadget *gadget,
> + struct otg_gadget_ops *ops);
> +int usb_otg_unregister_gadget(struct usb_gadget *gadget);
> +void usb_otg_sync_inputs(struct usb_otg *otg);
> +int usb_otg_kick_fsm(struct device *otg_dev);
> +int usb_otg_start_host(struct usb_otg *otg, int on);
> +int usb_otg_start_gadget(struct usb_otg *otg, int on);
> +
> +#else /* CONFIG_USB_OTG */
> +
> +static inline struct usb_otg *usb_otg_register(struct device *dev,
> + struct usb_otg_config *config)
> +{
> + return ERR_PTR(-ENOTSUPP);
> +}
> +
> +static inline int usb_otg_unregister(struct device *dev)
> +{
> + return -ENOTSUPP;
> +}
> +
> +static inline int usb_otg_register_hcd(struct usb_hcd *hcd, unsigned int irqnum,
> + unsigned long irqflags,
> + struct otg_hcd_ops *ops)
> +{
> + return -ENOTSUPP;
> +}
> +
> +static inline int usb_otg_unregister_hcd(struct usb_hcd *hcd)
> +{
> + return -ENOTSUPP;
> +}
> +
> +static inline int usb_otg_register_gadget(struct usb_gadget *gadget,
> + struct otg_gadget_ops *ops)
> +{
> + return -ENOTSUPP;
> +}
> +
> +static inline int usb_otg_unregister_gadget(struct usb_gadget *gadget)
> +{
> + return -ENOTSUPP;
> +}
> +
> +static inline void usb_otg_sync_inputs(struct usb_otg *otg)
> +{
> +}
> +
> +static inline int usb_otg_kick_fsm(struct device *otg_dev)
> +{
> + return -ENOTSUPP;
> +}
> +
> +static inline int usb_otg_start_host(struct usb_otg *otg, int on)
> +{
> + return -ENOTSUPP;
> +}
> +
> +static inline int usb_otg_start_gadget(struct usb_otg *otg, int on)
> +{
> + return -ENOTSUPP;
> +}
> +#endif /* CONFIG_USB_OTG */
> +
> +/*------------- deprecated interface -----------------------------*/
> /* Context: can sleep */
> static inline int
> otg_start_hnp(struct usb_otg *otg)
> @@ -113,6 +257,8 @@ otg_start_srp(struct usb_otg *otg)
> return -ENOTSUPP;
> }
>
> +/*---------------------------------------------------------------*/
> +
> /* for OTG controller drivers (and maybe other stuff) */
> extern int usb_bus_start_enum(struct usb_bus *bus, unsigned port_num);
>
> @@ -237,4 +383,6 @@ static inline int otg_start_gadget(struct usb_otg *otg, int on)
> return otg->fsm.ops->start_gadget(otg, on);
> }
>
> +int drd_statemachine(struct usb_otg *otg);
> +
> #endif /* __LINUX_USB_OTG_H */
> --
> 2.5.0
>
> --
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--
Best Regards,
Peter Chen