From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S933580AbbCRN43 (ORCPT ); Wed, 18 Mar 2015 09:56:29 -0400 Received: from arroyo.ext.ti.com ([192.94.94.40]:41746 "EHLO arroyo.ext.ti.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S933538AbbCRN4Y (ORCPT ); Wed, 18 Mar 2015 09:56:24 -0400 From: Roger Quadros To: , , CC: , , , , , , , Roger Quadros Subject: [RFC][PATCH 3/9] usb: otg: add OTG core Date: Wed, 18 Mar 2015 15:55:57 +0200 Message-ID: <1426686963-11613-4-git-send-email-rogerq@ti.com> X-Mailer: git-send-email 2.1.0 In-Reply-To: <1426686963-11613-1-git-send-email-rogerq@ti.com> References: <1426686963-11613-1-git-send-email-rogerq@ti.com> MIME-Version: 1.0 Content-Type: text/plain Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org 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 --- 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 + * + * 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 +#include +#include +#include +#include /* enum usb_otg_state */ +#include +#include +#include + +#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 */ +}; + +/* 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; + + 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 + * + * 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 + * + * 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 +#include +#include +#include +#include + +#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 From mboxrd@z Thu Jan 1 00:00:00 1970 From: Roger Quadros Subject: [RFC][PATCH 3/9] usb: otg: add OTG core Date: Wed, 18 Mar 2015 15:55:57 +0200 Message-ID: <1426686963-11613-4-git-send-email-rogerq@ti.com> References: <1426686963-11613-1-git-send-email-rogerq@ti.com> Mime-Version: 1.0 Content-Type: text/plain Return-path: In-Reply-To: <1426686963-11613-1-git-send-email-rogerq@ti.com> Sender: linux-kernel-owner@vger.kernel.org To: gregkh@linuxfoundation.org, balbi@ti.com, stern@rowland.harvard.edu Cc: dan.j.williams@intel.com, peter.chen@freescale.com, jun.li@freescale.com, mathias.nyman@linux.intel.com, linux-usb@vger.kernel.org, linux-kernel@vger.kernel.org, linux-omap@vger.kernel.org, Roger Quadros List-Id: linux-omap@vger.kernel.org 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 --- 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 + * + * 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 +#include +#include +#include +#include /* enum usb_otg_state */ +#include +#include +#include + +#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 */ +}; + +/* 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; + + 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 + * + * 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 + * + * 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 +#include +#include +#include +#include + +#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