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 | 1042 ++++++++++++++++++++++++++++++++++++++++++ drivers/usb/core/Kconfig | 4 +- 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 ++++++- 7 files changed, 1206 insertions(+), 6 deletions(-) create mode 100644 drivers/usb/common/usb-otg.c 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..64be6df --- /dev/null +++ b/drivers/usb/common/usb-otg.c @@ -0,0 +1,1042 @@ +/** + * 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/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> + +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; +} + +/** + * 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 *whcd; + struct otg_gcd *wgcd; + + 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"); + wgcd = &wait->gcd; + if (wgcd->gadget) + usb_otg_register_gadget(wgcd->gadget, wgcd->ops); + + whcd = &wait->primary_hcd; + if (whcd->hcd) + usb_otg_register_hcd(whcd->hcd, whcd->irqnum, whcd->irqflags, + whcd->ops); + + whcd = &wait->shared_hcd; + if (whcd->hcd) + usb_otg_register_hcd(whcd->hcd, whcd->irqnum, whcd->irqflags, + whcd->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) { + otg->gadget_ops->connect_control(otg->gadget, false); + 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); + otg->gadget_ops->connect_control(otg->gadget, true); + } + + 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; + 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; + + default: + dev_err(otg->dev, "%s: otg: invalid usb-drd state: %s\n", + __func__, usb_otg_state_string(state)); + 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); + +/** + * Dual-role device (DRD) work function + */ +static void usb_drd_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_err(dev, + "otg: otg_work must be provided for OTG support\n"); + ret = -EINVAL; + goto err_wq; + } + + if (config->otg_work) /* custom otg_work ? */ + INIT_WORK(&otg->work, config->otg_work); + else + INIT_WORK(&otg->work, usb_drd_work); + + otg->wq = create_freezable_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/core/Kconfig b/drivers/usb/core/Kconfig index ae228d0..de371e6 100644 --- a/drivers/usb/core/Kconfig +++ b/drivers/usb/core/Kconfig @@ -42,8 +42,8 @@ config USB_DYNAMIC_MINORS If you are unsure about this, say N here. config USB_OTG - bool "OTG support" - depends on PM + bool "OTG/Dual-role support" + depends on PM && USB_GADGET default n help The most notable feature of USB OTG is support for a diff --git a/include/linux/usb/gadget.h b/include/linux/usb/gadget.h index 20a2f8a..3ecfddd 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 26e6531..943714a 100644 --- a/include/linux/usb/otg-fsm.h +++ b/include/linux/usb/otg-fsm.h @@ -60,6 +60,11 @@ 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 @@ -132,6 +137,7 @@ 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 */ @@ -187,6 +193,7 @@ 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 */ -- 2.7.4 -- To unsubscribe from this list: send the line "unsubscribe devicetree" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
