On Wed, Mar 18, 2015 at 03:55:57PM +0200, Roger Quadros wrote: > The OTG core instantiates the OTG Finite State Machine > per OTG controller and manages starting/stopping the > host and gadget controllers based on the bus state. > > It provides APIs for the following tasks > > - Registering an OTG capable controller > - Registering Host and Gadget controllers to OTG core > - Providing inputs to and kicking the OTG state machine > > TODO: > - sysfs interface to allow application inputs to OTG state machine > - otg class? > > Signed-off-by: Roger Quadros <rogerq@xxxxxx> > --- > drivers/usb/Makefile | 1 + > drivers/usb/common/Makefile | 1 + > drivers/usb/common/usb-otg.c | 732 +++++++++++++++++++++++++++++++++++++++++++ > drivers/usb/common/usb-otg.h | 71 +++++ > drivers/usb/core/Kconfig | 8 + > include/linux/usb/usb-otg.h | 86 +++++ > 6 files changed, 899 insertions(+) > create mode 100644 drivers/usb/common/usb-otg.c > create mode 100644 drivers/usb/common/usb-otg.h > create mode 100644 include/linux/usb/usb-otg.h > > diff --git a/drivers/usb/Makefile b/drivers/usb/Makefile > index 2f1e2aa..07f59a5 100644 > --- a/drivers/usb/Makefile > +++ b/drivers/usb/Makefile > @@ -60,5 +60,6 @@ obj-$(CONFIG_USB_RENESAS_USBHS) += renesas_usbhs/ > obj-$(CONFIG_USB_GADGET) += gadget/ > > obj-$(CONFIG_USB_COMMON) += common/ > +obj-$(CONFIG_USB_OTG_CORE) += common/ > > obj-$(CONFIG_USBIP_CORE) += usbip/ > diff --git a/drivers/usb/common/Makefile b/drivers/usb/common/Makefile > index ca2f8bd..573fc75 100644 > --- a/drivers/usb/common/Makefile > +++ b/drivers/usb/common/Makefile > @@ -7,3 +7,4 @@ usb-common-y += common.o > usb-common-$(CONFIG_USB_LED_TRIG) += led.o > > obj-$(CONFIG_USB_OTG_FSM) += usb-otg-fsm.o > +obj-$(CONFIG_USB_OTG_CORE) += usb-otg.o > diff --git a/drivers/usb/common/usb-otg.c b/drivers/usb/common/usb-otg.c > new file mode 100644 > index 0000000..1433fc9 > --- /dev/null > +++ b/drivers/usb/common/usb-otg.c > @@ -0,0 +1,732 @@ > +/** > + * drivers/usb/common/usb-otg.c - USB OTG core > + * > + * Copyright (C) 2015 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/list.h> > +#include <linux/timer.h> > +#include <linux/usb/otg.h> > +#include <linux/usb/phy.h> /* enum usb_otg_state */ > +#include <linux/usb/gadget.h> > +#include <linux/usb/usb-otg.h> > +#include <linux/workqueue.h> > + > +#include "usb-otg.h" > + > +/* to link timer with callback data */ > +struct otg_timer { > + struct timer_list timer; > + /* callback data */ > + int *timeout_bit; > + struct otg_data *otgd; > +}; > + > +struct otg_data { > + struct device *dev; /* HCD & GCD's parent device */ > + > + struct otg_fsm fsm; > + /* HCD, GCD and usb_otg_state are present in otg_fsm->otg > + * HCD is bus_to_hcd(fsm->otg->host) > + * GCD is fsm->otg->gadget > + */ > + struct otg_fsm_ops fsm_ops; /* private copy for override */ > + struct usb_otg otg; > + struct usb_hcd *shared_hcd; /* if shared HCD registered */ > + > + /* saved hooks to OTG device */ > + int (*start_host)(struct otg_fsm *fsm, int on); > + int (*start_gadget)(struct otg_fsm *fsm, int on); > + > + struct list_head list; > + > + struct work_struct work; /* OTG FSM work */ > + struct workqueue_struct *wq; > + > + struct otg_timer timers[NUM_OTG_FSM_TIMERS]; > + > + bool fsm_running; > + bool gadget_can_start; /* OTG FSM says gadget can start */ > + bool host_can_start; /* OTG FSM says host can start */ > + > + /* use otg->fsm.lock for serializing access */ > +}; What's the relationship between struct usb_otg otg and this one? > + > +/* OTG device list */ > +LIST_HEAD(otg_list); > +static DEFINE_MUTEX(otg_list_mutex); > + > +/** > + * check if device is in our OTG list and return > + * otg_data, else NULL. > + * > + * otg_list_mutex must be held. > + */ > +static struct otg_data *usb_otg_device_get_otgd(struct device *parent_dev) > +{ > + struct otg_data *otgd; > + > + list_for_each_entry(otgd, &otg_list, list) { > + if (otgd->dev == parent_dev) > + return otgd; > + } > + > + return NULL; > +} > + > +/** > + * timer callback to set timeout bit and kick FSM > + */ > +static void set_tmout(unsigned long data) > +{ > + struct otg_timer *tmr_data; > + > + tmr_data = (struct otg_timer *)data; > + > + if (tmr_data->timeout_bit) > + *tmr_data->timeout_bit = 1; > + > + usb_otg_sync_inputs(&tmr_data->otgd->fsm); > +} > + > +/** > + * Initialize one OTG timer with callback, timeout and timeout bit > + */ > +static void otg_timer_init(enum otg_fsm_timer id, struct otg_data *otgd, > + void (*callback)(unsigned long), > + unsigned long expires_ms, > + int *timeout_bit) > +{ > + struct otg_timer *otgtimer = &otgd->timers[id]; > + struct timer_list *timer = &otgtimer->timer; > + > + init_timer(timer); > + timer->function = callback; > + timer->expires = jiffies + msecs_to_jiffies(expires_ms); > + timer->data = (unsigned long)otgtimer; > + The timer for TB_DATA_PLS is about 10ms or less, it is not suitable for using kernel timer, hrtimer is suitable choice. > + otgtimer->timeout_bit = timeout_bit; > + otgtimer->otgd = otgd; > +} > + > +/** > + * Initialize standard OTG timers > + */ > +static void usb_otg_init_timers(struct otg_data *otgd) > +{ > + struct otg_fsm *fsm = &otgd->fsm; > + > + otg_timer_init(A_WAIT_VRISE, otgd, set_tmout, TA_WAIT_VRISE, &fsm->a_wait_vrise_tmout); > + otg_timer_init(A_WAIT_VFALL, otgd, set_tmout, TA_WAIT_VFALL, &fsm->a_wait_vfall_tmout); > + otg_timer_init(A_WAIT_BCON, otgd, set_tmout, TA_WAIT_BCON, &fsm->a_wait_bcon_tmout); > + otg_timer_init(A_AIDL_BDIS, otgd, set_tmout, TA_AIDL_BDIS, &fsm->a_aidl_bdis_tmout); > + otg_timer_init(A_BIDL_ADIS, otgd, set_tmout, TA_BIDL_ADIS, &fsm->a_bidl_adis_tmout); > + otg_timer_init(B_ASE0_BRST, otgd, set_tmout, TB_ASE0_BRST, &fsm->b_ase0_brst_tmout); > + > + otg_timer_init(B_SE0_SRP, otgd, set_tmout, TB_SE0_SRP, &fsm->b_se0_srp); > + otg_timer_init(B_SRP_FAIL, otgd, set_tmout, TB_SRP_FAIL, &fsm->b_srp_done); > + > + otg_timer_init(A_WAIT_ENUM, otgd, set_tmout, TB_SRP_FAIL, NULL); > +} > + > +/** > + * OTG FSM ops function to add timer > + */ > +static void usb_otg_add_timer(struct otg_fsm *fsm, enum otg_fsm_timer id) > +{ > + struct otg_data *otgd = container_of(fsm, struct otg_data, fsm); > + struct timer_list *timer = &otgd->timers[id].timer; > + > + if (!otgd->fsm_running) > + return; > + > + /* if timer is already active, exit */ > + if (timer_pending(timer)) { > + dev_err(otgd->dev, "USB-OTG: Timer %d is already running\n", > + id); > + } > + > + add_timer(timer); > +} > + > +/** > + * OTG FSM ops function to delete timer > + */ > +static void usb_otg_del_timer(struct otg_fsm *fsm, enum otg_fsm_timer id) > +{ > + struct otg_data *otgd = container_of(fsm, struct otg_data, fsm); > + struct timer_list *timer = &otgd->timers[id].timer; > + > + del_timer(timer); > +} > + > +/** > + * OTG FSM ops function to start/stop host > + */ > +static int usb_otg_start_host(struct otg_fsm *fsm, int on) > +{ > + struct otg_data *otgd = container_of(fsm, struct otg_data, fsm); > + int ret = 0; > + struct usb_hcd *hcd; > + > + dev_info(otgd->dev, "%s %d\n", __func__, on); > + if (!fsm->otg->host) { > + WARN_ONCE(1, "OTG FSM running without Host\n"); > + return 0; > + } > + > + hcd = bus_to_hcd(fsm->otg->host); > + otgd->host_can_start = on; > + if (hcd->shared_hcd && !otgd->shared_hcd) { > + dev_info(otgd->dev, "%s: waiting for Shared HCD to register\n", > + __func__); > + return 0; > + } > + > + /* call OTG device operations */ > + if (otgd->start_host) { > + ret = otgd->start_host(fsm, on); > + if (ret) > + return ret; > + } > + > + if (on) { > + usb_start_hcd(hcd); > + if (hcd->shared_hcd) > + usb_start_hcd(hcd->shared_hcd); > + } else { > + if (hcd->shared_hcd) > + usb_stop_hcd(hcd->shared_hcd); > + usb_stop_hcd(hcd); > + } > + > + return 0; > +} > + > +/** > + * OTG FSM ops function to start/stop gadget > + */ > +static int usb_otg_start_gadget(struct otg_fsm *fsm, int on) > +{ > + struct otg_data *otgd = container_of(fsm, struct otg_data, fsm); > + int ret = 0; > + struct usb_gadget *gadget = fsm->otg->gadget; > + > + dev_info(otgd->dev, "%s %d\n", __func__, on); > + if (!gadget) { > + WARN_ONCE(1, "OTG FSM running without Gadget\n"); > + return 0; > + } > + > + /* call OTG device operations */ > + if (otgd->start_gadget) { > + ret = otgd->start_gadget(fsm, on); > + if (ret) > + return ret; > + } > + > + otgd->gadget_can_start = on; > + if (on) > + usb_gadget_start(fsm->otg->gadget); > + else > + usb_gadget_stop(fsm->otg->gadget); > + > + return 0; > +} > + > +/** > + * OTG FSM work function > + */ > +static void usb_otg_work(struct work_struct *work) > +{ > + struct otg_data *otgd = container_of(work, struct otg_data, work); > + > + if (otg_statemachine(&otgd->fsm)) { > + /* state changed. any action ? */ > + } > +} > + > +/** > + * usb_otg_register() - Register the OTG device to OTG core > + * @parent_device: parent device of Host & Gadget controllers. > + * @otg_fsm_ops: otg state machine ops. > + * > + * Register parent device that contains both HCD and GCD into > + * the USB OTG core. HCD and GCD will be prevented from starting > + * till both are available for use. > + * > + * Return: struct otg_fsm * if success, NULL if error. > + */ > +struct otg_fsm *usb_otg_register(struct device *parent_dev, > + struct otg_fsm_ops *fsm_ops) > +{ > + struct otg_data *otgd; > + int ret = 0; > + > + if (!parent_dev || !fsm_ops) > + return ERR_PTR(-EINVAL); > + > + /* already in list? */ > + mutex_lock(&otg_list_mutex); > + if (usb_otg_device_get_otgd(parent_dev)) { > + dev_err(parent_dev, "%s: device already in OTG list\n", > + __func__); > + ret = -EINVAL; > + goto unlock; > + } > + > + /* allocate and add to list */ > + otgd = kzalloc(sizeof(*otgd), GFP_KERNEL); > + if (!otgd) { > + ret = -ENOMEM; > + goto unlock; > + } > + > + otgd->dev = parent_dev; > + INIT_WORK(&otgd->work, usb_otg_work); > + otgd->wq = create_singlethread_workqueue("usb_otg"); > + if (!otgd->wq) { > + dev_err(parent_dev, "%s: can't create workqueue\n", __func__); > + ret = -ENODEV; > + goto err_wq; > + } > + > + usb_otg_init_timers(otgd); > + > + /* save original start host/gadget ops */ > + otgd->start_host = fsm_ops->start_host; > + otgd->start_gadget = fsm_ops->start_gadget; > + /* create copy of original ops */ > + otgd->fsm_ops = *fsm_ops; > + /* override ops */ > + otgd->fsm_ops.start_host = usb_otg_start_host; > + otgd->fsm_ops.start_gadget = usb_otg_start_gadget; > + /* FIXME: we ignore caller's timer ops */ > + otgd->fsm_ops.add_timer = usb_otg_add_timer; > + otgd->fsm_ops.del_timer = usb_otg_del_timer; > + /* set otg ops */ > + otgd->fsm.ops = &otgd->fsm_ops; > + otgd->fsm.otg = &otgd->otg; > + > + mutex_init(&otgd->fsm.lock); > + > + list_add_tail(&otgd->list, &otg_list); > + mutex_unlock(&otg_list_mutex); > + return &otgd->fsm; > + > +err_wq: > + kfree(otgd); > +unlock: > + mutex_unlock(&otg_list_mutex); > + return ERR_PTR(ret); > +} > +EXPORT_SYMBOL_GPL(usb_otg_register); > + > +/** > + * usb_otg_unregister() - Unregister the OTG device from USB OTG core > + * @parent_device: parent device of Host & Gadget controllers. > + * > + * Unregister parent OTG deviced from USB OTG core. > + * Prevents unregistering till both Host and Gadget controllers > + * have unregistered from the OTG core. > + * > + * Return: 0 on success, error value otherwise. > + */ > +int usb_otg_unregister(struct device *parent_dev) > +{ > + struct otg_data *otgd; > + > + mutex_lock(&otg_list_mutex); > + otgd = usb_otg_device_get_otgd(parent_dev); > + if (!otgd) { > + dev_err(parent_dev, "%s: device not in OTG list\n", > + __func__); > + mutex_unlock(&otg_list_mutex); > + return -EINVAL; > + } > + > + /* prevent unregister till both host & gadget have unregistered */ > + if (otgd->fsm.otg->host || otgd->fsm.otg->gadget) { > + dev_err(parent_dev, "%s: host/gadget still registered\n", > + __func__); > + return -EBUSY; > + } > + > + /* OTG FSM is halted when host/gadget unregistered */ > + destroy_workqueue(otgd->wq); > + > + /* remove from otg list */ > + list_del(&otgd->list); > + kfree(otgd); > + 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 otg_fsm *fsm) > +{ > + struct otg_data *otgd = container_of(fsm, struct otg_data, fsm); > + > + if (otgd->fsm_running) > + goto kick_fsm; > + > + if (!fsm->otg->host) { > + dev_info(otgd->dev, "Not starting OTG till Host registers\n"); > + return; > + } > + > + if (!fsm->otg->gadget) { > + dev_info(otgd->dev, "Not starting OTG till Gadget registers\n"); > + return; > + } > + > + otgd->fsm_running = true; > +kick_fsm: > + queue_work(otgd->wq, &otgd->work); > +} > + > +/** > + * stop the OTG FSM. Stops Host & Gadget controllers as well. > + * fsm->lock must be held > + */ > +static void usb_otg_stop_fsm(struct otg_fsm *fsm) > +{ > + struct otg_data *otgd = container_of(fsm, struct otg_data, fsm); > + int i; > + > + if (!otgd->fsm_running) > + return; > + > + /* no more new events queued */ > + otgd->fsm_running = false; > + > + /* Stop state machine / timers */ > + for (i = 0; i < ARRAY_SIZE(otgd->timers); i++) > + del_timer_sync(&otgd->timers[i].timer); > + > + flush_workqueue(otgd->wq); > + > + /* stop host/gadget immediately */ > + if (fsm->protocol == PROTO_HOST) > + otg_start_host(fsm, 0); > + else if (fsm->protocol == PROTO_GADGET) > + otg_start_gadget(fsm, 0); > +} > + > +/** > + * 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 otg_fsm *fsm) > +{ > + struct otg_data *otgd = container_of(fsm, struct otg_data, fsm); > + > + /* Don't kick FSM till it has started */ > + if (!otgd->fsm_running) > + return; > + > + /* Kick FSM */ > + queue_work(otgd->wq, &otgd->work); > +} > +EXPORT_SYMBOL_GPL(usb_otg_sync_inputs); > + > +/** > + * usb_otg_kick_fsm - Kick the OTG state machine > + * @hcd_gcd_device: Host/Gadget 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 *hcd_gcd_device) > +{ > + struct otg_data *otgd; > + > + mutex_lock(&otg_list_mutex); > + otgd = usb_otg_device_get_otgd(hcd_gcd_device->parent); > + if (!otgd) { > + dev_err(hcd_gcd_device, "%s: invalid host/gadget device\n", > + __func__); > + mutex_unlock(&otg_list_mutex); > + return -ENODEV; > + } > + > + mutex_unlock(&otg_list_mutex); > + usb_otg_sync_inputs(&otgd->fsm); > + > + return 0; > +} > +EXPORT_SYMBOL_GPL(usb_otg_kick_fsm); > + > +/** > + * usb_otg_register_hcd - Register Host controller to OTG core > + * @hcd: Host controller device > + * > + * 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. > + * > + * Returns: 0 on success, error value otherwise. > + */ > +int usb_otg_register_hcd(struct usb_hcd *hcd) > +{ > + struct otg_data *otgd; > + struct usb_bus *bus = hcd_to_bus(hcd); > + struct device *otg_dev = bus->controller->parent; > + > + mutex_lock(&otg_list_mutex); > + otgd = usb_otg_device_get_otgd(otg_dev); > + if (!otgd) { > + dev_err(otg_dev, "%s: device not registered to OTG core\n", > + __func__); > + mutex_unlock(&otg_list_mutex); > + return -EINVAL; > + } > + > + mutex_unlock(&otg_list_mutex); > + /* HCD will be started by OTG fsm when needed */ > + mutex_lock(&otgd->fsm.lock); > + if (otgd->fsm.otg->host) { > + /* probably a shared hcd ? */ > + if (usb_hcd_is_primary_hcd(hcd)) { > + dev_err(otg_dev, "%s: hcd already registered\n", > + __func__); > + goto err; > + } > + > + if (hcd->shared_hcd == bus_to_hcd(otgd->fsm.otg->host)) { > + if (otgd->shared_hcd) { > + dev_err(otg_dev, "%s: shared HCD already registered\n", > + __func__); > + goto err; > + } > + > + otgd->shared_hcd = hcd; > + dev_info(otg_dev, "USB-OTG: Shared Host %s registered\n", > + dev_name(bus->controller)); > + /* we might be pending a start_host */ > + if (otgd->host_can_start) > + usb_otg_start_host(&otgd->fsm, 1); > + goto unlock; > + } else { > + dev_err(otg_dev, "%s: invalid shared hcd\n", > + __func__); > + goto err; > + } > + } > + > + otgd->fsm.otg->host = bus; > + > + /* FIXME: set bus->otg_port if this is true OTG port with HNP */ > + dev_info(otg_dev, "USB-OTG: Primary Host %s registered\n", > + dev_name(bus->controller)); > + > +unlock: > + /* Kick FSM */ > + usb_otg_start_fsm(&otgd->fsm); > + mutex_unlock(&otgd->fsm.lock); > + > + return 0; > + > +err: > + mutex_unlock(&otgd->fsm.lock); > + return -EINVAL; > +} > +EXPORT_SYMBOL_GPL(usb_otg_register_hcd); > + > +/** > + * usb_otg_unregister_hcd - Unregister 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 otg_data *otgd; > + struct usb_bus *bus = hcd_to_bus(hcd); > + struct device *otg_dev = bus->controller->parent; > + > + mutex_lock(&otg_list_mutex); > + otgd = usb_otg_device_get_otgd(otg_dev); > + if (!otgd) { > + dev_err(otg_dev, "%s: device not registered to OTG core\n", > + __func__); > + mutex_unlock(&otg_list_mutex); > + return -EINVAL; > + } > + > + mutex_unlock(&otg_list_mutex); > + > + mutex_lock(&otgd->fsm.lock); > + if (otgd->fsm.otg->host != bus) { > + dev_err(otg_dev, "%s: host wansn't registered with OTG\n", > + __func__); > + mutex_unlock(&otgd->fsm.lock); > + return -EINVAL; > + } > + > + /* stop FSM & Host */ > + usb_otg_stop_fsm(&otgd->fsm); > + otgd->fsm.otg->host = NULL; > + > + mutex_unlock(&otgd->fsm.lock); > + dev_info(otg_dev, "USB-OTG: Host %s unregistered\n", > + dev_name(bus->controller)); > + > + return 0; > +} > +EXPORT_SYMBOL_GPL(usb_otg_unregister_hcd); > + > +/** > + * usb_otg_register_gadget - Register 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. > + * > + * As gadget controller needs to be prevented from starting till other > + * conditions are met (i.e. driver loaded, softconnet enabled), > + * the gadget stack can use the usb_otg_gadget_can_start() function > + * to check if OTG core has given the permission to start the gadget. > + * > + * Returns: 0 on success, error value otherwise. > + */ > +int usb_otg_register_gadget(struct usb_gadget *gadget) > +{ > + struct otg_data *otgd; > + struct device *otg_dev = gadget->dev.parent; > + > + mutex_lock(&otg_list_mutex); > + otgd = usb_otg_device_get_otgd(otg_dev); > + if (!otgd) { > + dev_err(otg_dev, "%s: device not registered to OTG core\n", > + __func__); > + mutex_unlock(&otg_list_mutex); > + return -EINVAL; > + } > + > + mutex_unlock(&otg_list_mutex); > + > + mutex_lock(&otgd->fsm.lock); > + if (otgd->fsm.otg->gadget) { > + dev_err(otg_dev, "%s: gadget already registered with OTG\n", > + __func__); > + mutex_unlock(&otgd->fsm.lock); > + return -EINVAL; > + } > + > + otgd->fsm.otg->gadget = gadget; > + dev_info(otg_dev, "USB-OTG: Gadget %s registered\n", > + dev_name(&gadget->dev)); > + > + /* Kick FSM */ > + usb_otg_start_fsm(&otgd->fsm); > + mutex_unlock(&otgd->fsm.lock); > + > + return 0; > +} > +EXPORT_SYMBOL_GPL(usb_otg_register_gadget); > + > +/** > + * usb_otg_unregister_gadget - Unregister 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 not running > + * on successful return. > + * > + * Returns: 0 on success, error value otherwise. > + */ > +int usb_otg_unregister_gadget(struct usb_gadget *gadget) > +{ > + struct otg_data *otgd; > + struct device *otg_dev = gadget->dev.parent; > + > + mutex_lock(&otg_list_mutex); > + otgd = usb_otg_device_get_otgd(otg_dev); > + if (!otgd) { > + dev_err(otg_dev, "%s: device not registered to OTG core\n", > + __func__); > + mutex_unlock(&otg_list_mutex); > + return -EINVAL; > + } > + > + mutex_unlock(&otg_list_mutex); > + > + mutex_lock(&otgd->fsm.lock); > + if (otgd->fsm.otg->gadget != gadget) { > + dev_err(otg_dev, "%s: gadget wasn't registered with OTG\n", > + __func__); > + mutex_unlock(&otgd->fsm.lock); > + return -EINVAL; > + } > + > + /* Stop FSM & gadget */ > + usb_otg_stop_fsm(&otgd->fsm); > + otgd->fsm.otg->gadget = NULL; > + mutex_unlock(&otgd->fsm.lock); > + > + dev_info(otg_dev, "USB-OTG: Gadget %s unregistered\n", > + dev_name(&gadget->dev)); > + > + return 0; > +} > +EXPORT_SYMBOL_GPL(usb_otg_unregister_gadget); > + > +/** > + * usb_otg_gadget_can_start - check if Gadget can be started from OTG perspective > + * @gadget: Gadget controller > + * > + * This is used by the USB Gadget stack to check if Gadget controller > + * can be started from the OTG state machines perspective. > + * i.e. we're in 'b_peripheral' state. > + * > + * Returns: 0 on success, error value otherwise. > + */ > +bool usb_otg_gadget_can_start(struct usb_gadget *gadget) > +{ > + struct otg_data *otgd; > + struct device *otg_dev = gadget->dev.parent; > + > + mutex_lock(&otg_list_mutex); > + otgd = usb_otg_device_get_otgd(otg_dev); > + if (!otgd) { > + dev_err(otg_dev, "%s: device not registered to OTG core\n", > + __func__); > + mutex_unlock(&otg_list_mutex); > + return -EINVAL; > + } > + > + mutex_unlock(&otg_list_mutex); > + > + return otgd->gadget_can_start; > +} > +EXPORT_SYMBOL_GPL(usb_otg_gadget_can_start); > diff --git a/drivers/usb/common/usb-otg.h b/drivers/usb/common/usb-otg.h > new file mode 100644 > index 0000000..05331f0 > --- /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) 2015 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 cc0ced0..43a0d2d 100644 > --- a/drivers/usb/core/Kconfig > +++ b/drivers/usb/core/Kconfig > @@ -84,3 +84,11 @@ config USB_OTG_FSM > Implements OTG Finite State Machine as specified in On-The-Go > and Embedded Host Supplement to the USB Revision 2.0 Specification. > > +config USB_OTG_CORE > + tristate "USB OTG core" > + depends on USB > + select USB_OTG_FSM > + help > + Standardize the way OTG is implemented on Linux. The OTG state > + machine is instantiated here instead of being done in each controller > + driver. > diff --git a/include/linux/usb/usb-otg.h b/include/linux/usb/usb-otg.h > new file mode 100644 > index 0000000..52ab7b1 > --- /dev/null > +++ b/include/linux/usb/usb-otg.h > @@ -0,0 +1,86 @@ > +/** > + * include/linux/usb/usb-otg.h - USB OTG core > + * > + * Copyright (C) 2015 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 __LINUX_USB_OTG_CORE_H > +#define __LINUX_USB_OTG_CORE_H > + > +#include <linux/device.h> > +#include <linux/usb.h> > +#include <linux/usb/hcd.h> > +#include <linux/usb/gadget.h> > +#include <linux/usb/otg-fsm.h> > + > +#if IS_ENABLED(CONFIG_USB_OTG_CORE) > +struct otg_fsm *usb_otg_register(struct device *parent_dev, > + struct otg_fsm_ops *fsm_ops); > +int usb_otg_unregister(struct device *parent_dev); > +int usb_otg_register_hcd(struct usb_hcd *hcd); > +int usb_otg_unregister_hcd(struct usb_hcd *hcd); > +int usb_otg_register_gadget(struct usb_gadget *gadget); > +int usb_otg_unregister_gadget(struct usb_gadget *gadget); > +void usb_otg_sync_inputs(struct otg_fsm *fsm); > +int usb_otg_kick_fsm(struct device *hcd_gcd_device); > +bool usb_otg_gadget_can_start(struct usb_gadget *gadget); > + > +#else /* CONFIG_USB_OTG_CORE */ > + > +static inline struct otg_fsm *usb_otg_register(struct device *parent_dev, > + struct otg_fsm_ops *fsm_ops) > +{ > + return ERR_PTR(-ENOSYS); > +} > + > +static inline int usb_otg_unregister(struct device *parent_dev) > +{ > + return -ENOSYS; > +} > + > +static inline int usb_otg_register_hcd(struct usb_hcd *hcd) > +{ > + return -ENOSYS; > +} > + > +int usb_otg_unregister_hcd(struct usb_hcd *hcd) > +{ > + return -ENOSYS; > +} > + > +static inline int usb_otg_register_gadget(struct usb_gadget *gadget) > +{ > + return -ENOSYS; > +} > + > +static inline int usb_otg_unregister_gadget(struct usb_gadget *gadget) > +{ > + return -ENOSYS; > +} > + > +static inline void usb_otg_sync_inputs(struct otg_fsm *fsm) > +{ > +} > + > +int usb_otg_kick_fsm(struct device *hcd_gcd_device) > +{ > + return -ENOSYS; > +} > + > +bool usb_otg_gadget_can_start(struct usb_gadget *gadget) > +{ > + return true; > +} > +#endif /* CONFIG_USB_OTG_CORE */ > + > +#endif /* __LINUX_USB_OTG_CORE */ > -- > 2.1.0 > -- Best Regards, Peter Chen -- To unsubscribe from this list: send the line "unsubscribe linux-omap" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
