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> --- v11: - remove usb_otg_kick_fsm(). - typo fixes: structa/structure, upto/up to. - remove "obj-$(CONFIG_USB_OTG_CORE) += common/" from Makefile. drivers/usb/Kconfig | 18 + drivers/usb/common/Makefile | 6 +- drivers/usb/common/usb-otg.c | 877 +++++++++++++++++++++++++++++++++++++++++++ drivers/usb/core/Kconfig | 14 - drivers/usb/gadget/Kconfig | 1 + include/linux/usb/gadget.h | 2 + include/linux/usb/hcd.h | 1 + include/linux/usb/otg-fsm.h | 7 + include/linux/usb/otg.h | 174 ++++++++- 9 files changed, 1070 insertions(+), 30 deletions(-) create mode 100644 drivers/usb/common/usb-otg.c diff --git a/drivers/usb/Kconfig b/drivers/usb/Kconfig index 8689dcb..ed596ec 100644 --- a/drivers/usb/Kconfig +++ b/drivers/usb/Kconfig @@ -32,6 +32,23 @@ if USB_SUPPORT config USB_COMMON tristate +config USB_OTG_CORE + tristate + +config USB_OTG + bool "OTG/Dual-role support" + depends on PM && USB && USB_GADGET + default n + ---help--- + The most notable feature of USB OTG is support for a + "Dual-Role" device, which can act as either a device + or a host. The initial role is decided by the type of + plug inserted and can be changed later when two dual + role devices talk to each other. + + Select this only if your board has Mini-AB/Micro-AB + connector. + config USB_ARCH_HAS_HCD def_bool y @@ -40,6 +57,7 @@ config USB tristate "Support for Host-side USB" depends on USB_ARCH_HAS_HCD select USB_COMMON + select USB_OTG_CORE select NLS # for UTF-8 strings ---help--- Universal Serial Bus (USB) is a specification for a serial bus diff --git a/drivers/usb/common/Makefile b/drivers/usb/common/Makefile index f8f2c88..5122b3f 100644 --- a/drivers/usb/common/Makefile +++ b/drivers/usb/common/Makefile @@ -7,5 +7,7 @@ usb-common-y += common.o usb-common-$(CONFIG_USB_LED_TRIG) += led.o obj-$(CONFIG_USB_ULPI_BUS) += ulpi.o -usbotg-y := usb-otg-fsm.o -obj-$(CONFIG_USB_OTG) += usbotg.o +ifeq ($(CONFIG_USB_OTG),y) +usbotg-y := usb-otg.o usb-otg-fsm.o +obj-$(CONFIG_USB_OTG_CORE) += usbotg.o +endif diff --git a/drivers/usb/common/usb-otg.c b/drivers/usb/common/usb-otg.c new file mode 100644 index 0000000..a23ab1e --- /dev/null +++ b/drivers/usb/common/usb-otg.c @@ -0,0 +1,877 @@ +/** + * 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/module.h> +#include <linux/of.h> +#include <linux/of_platform.h> +#include <linux/usb/of.h> +#include <linux/usb/otg.h> +#include <linux/usb/gadget.h> +#include <linux/workqueue.h> + +/* OTG device list */ +LIST_HEAD(otg_list); +static DEFINE_MUTEX(otg_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; +} + +/** + * usb_otg_get_data() - get usb_otg data structure + * @otg_dev: OTG controller device + * + * Check if the OTG device is in our OTG list and return + * usb_otg data, else NULL. + * + * otg_list_mutex must be held. + * + * Return: usb_otg data on success, NULL otherwise. + */ +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. + * + * Return: 0 on success, error value otherwise. + */ +int usb_otg_start_host(struct usb_otg *otg, int on) +{ + struct otg_hcd_ops *hcd_ops = otg->hcd_ops; + int ret; + + 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; + + /* start host */ + ret = hcd_ops->add(otg->primary_hcd.hcd, + otg->primary_hcd.irqnum, + otg->primary_hcd.irqflags); + if (ret) { + dev_err(otg->dev, "otg: host add failed %d\n", ret); + return ret; + } + + if (otg->shared_hcd.hcd) { + ret = hcd_ops->add(otg->shared_hcd.hcd, + otg->shared_hcd.irqnum, + otg->shared_hcd.irqflags); + if (ret) { + dev_err(otg->dev, "otg: shared host add failed %d\n", + ret); + hcd_ops->remove(otg->primary_hcd.hcd); + return ret; + } + } + otg->flags |= OTG_FLAG_HOST_RUNNING; + } 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. + * + * Return: 0 on success, error value otherwise. + */ +int usb_otg_start_gadget(struct usb_otg *otg, int on) +{ + struct usb_gadget *gadget = otg->gadget; + int ret; + + 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; + + ret = otg->gadget_ops->start(otg->gadget); + if (ret) { + dev_err(otg->dev, "otg: gadget start failed: %d\n", + ret); + return ret; + } + + otg->flags |= OTG_FLAG_GADGET_RUNNING; + } else { + if (!(otg->flags & OTG_FLAG_GADGET_RUNNING)) + return 0; + + ret = otg->gadget_ops->stop(otg->gadget); + if (ret) { + dev_err(otg->dev, "otg: gadget stop failed: %d\n", + ret); + return ret; + } + otg->flags &= ~OTG_FLAG_GADGET_RUNNING; + } + + return 0; +} +EXPORT_SYMBOL_GPL(usb_otg_start_gadget); + +/** + * drd_set_protocol() - Set USB protocol if possible + * @fsm: DRD FSM instance + * @protocol: USB protocol to set the state machine to + * + * Sets the OTG FSM protocol to @protocol if it changed. + * fsm->lock must be held. + * + * Return: 0 on success, error value otherwise. + */ +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; +} + +/** + * drd_set_state() - Set the DRD state machine state. + * @fsm: DRD FSM instance + * @new_state: the new state the DRD FSM must be set to + * + * Sets the state of the DRD state machine. + * 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_statemachine() - DRD state change judgement + * @otg: usb_otg instance + * + * Checks the state machine inputs and state and makes a state change + * if required. + * + * 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 + * + * Return: 0 if state wasn't changed, 1 if state changed. + */ +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); + +/** + * usb_drd_work() - Dual-role state machine work function + * @work: work_struct context + * + * Runs the DRD state machine. Scheduled whenever there is a change + * in FSM inputs. + */ +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); + while (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() otherwise. + */ +struct usb_otg *usb_otg_register(struct device *dev, + struct usb_otg_config *config) +{ + struct usb_otg *otg; + 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 is controller caps + DT overrides */ + otg->caps = *config->otg_caps; + ret = of_usb_update_otg_caps(dev->of_node, &otg->caps); + if (ret) + goto err_wq; + + 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); + + 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__); + mutex_unlock(&otg_list_mutex); + 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); + +/** + * usb_otg_start_fsm() - Start the OTG FSM + * @otg: usb_otg instance + * + * Start the OTG FSM if we can. The HCD, UDC and gadget function driver + * must be ready for the OTG FSM to start. + * + * 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 UDC registers\n"); + return; + } + + if (!otg->gadget_ready) { + dev_info(otg->dev, + "otg: can't start till gadget function registers\n"); + return; + } + + fsm->running = true; +kick_fsm: + queue_work(otg->wq, &otg->work); +} + +/** + * usb_otg_stop_fsm() - Stop the OTG FSM + * @otg: usb_otg instance + * + * Stops the HCD, UDC and the OTG FSM. + * + * 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->gadget_ops->connect_control(otg->gadget, false); + otg_start_gadget(otg, 0); + } + fsm->protocol = PROTO_UNDEF; +} + +/** + * usb_otg_sync_inputs() - Sync OTG inputs with the OTG state machine + * @otg: usb_otg 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_register_hcd() - Register the host controller to OTG core + * @hcd: host controller + * @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 up to the OTG state machine to do so. + * hcd->otg_dev must contain the related otg controller device. + * + * Return: 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. deferring.\n"); + return -EPROBE_DEFER; + } + + /* 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) { + dev_err(hcd_dev, "otg: host %s wasn't registered with otg\n", + dev_name(hcd_dev)); + 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 { + mutex_unlock(&otg->fsm.lock); + dev_err(otg_dev, "otg: host %s wasn't registered with otg\n", + dev_name(hcd_dev)); + 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 instance + * @ops: gadget interface ops + * + * 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 up to the OTG state machine to do so. + * + * 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, deferring.\n"); + return -EPROBE_DEFER; + } + + 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)); + + /* FSM will be started in usb_otg_gadget_ready() */ + 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 not running + * 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) { + dev_err(gadget_dev, + "otg: gadget %s wasn't registered with otg\n", + dev_name(&gadget->dev)); + return -EINVAL; + } + + mutex_lock(&otg->fsm.lock); + if (otg->gadget != gadget) { + mutex_unlock(&otg->fsm.lock); + dev_err(otg_dev, "otg: gadget %s wasn't registered with otg\n", + dev_name(&gadget->dev)); + return -EINVAL; + } + + /* FSM must be stopped in usb_otg_gadget_ready() */ + if (otg->gadget_ready) { + dev_err(otg_dev, + "otg: gadget %s unregistered before being unready, forcing stop\n", + dev_name(&gadget->dev)); + 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); + +/** + * usb_otg_gadget_ready() - Notify gadget function driver ready status + * @gadget: gadget controller + * @ready: 0: function driver ready, 1: function driver not ready + * + * Notify the OTG core about status of the gadget function driver. + * As OTG core is responsible to start/stop the gadget controller, it + * must be aware when the gadget function driver is available or not. + * This function is used by the Gadget core to inform the OTG core + * about the gadget function driver readyness. + * + * Return: 0 on sucess, error value otherwise. + */ +int usb_otg_gadget_ready(struct usb_gadget *gadget, bool ready) +{ + 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) { + dev_err(gadget_dev, + "otg: gadget %s wasn't registered with otg\n", + dev_name(&gadget->dev)); + return -EINVAL; + } + + mutex_lock(&otg->fsm.lock); + if (otg->gadget != gadget) { + mutex_unlock(&otg->fsm.lock); + dev_err(otg_dev, "otg: gadget %s wasn't registered with otg\n", + dev_name(&gadget->dev)); + return -EINVAL; + } + + /* Start/stop FSM & gadget */ + otg->gadget_ready = ready; + if (ready) + usb_otg_start_fsm(otg); + else + usb_otg_stop_fsm(otg); + + dev_dbg(otg_dev, "otg: gadget %s %sready\n", dev_name(&gadget->dev), + ready ? "" : "not "); + + mutex_unlock(&otg->fsm.lock); + + return 0; +} +EXPORT_SYMBOL_GPL(usb_otg_gadget_ready); + +MODULE_LICENSE("GPL"); diff --git a/drivers/usb/core/Kconfig b/drivers/usb/core/Kconfig index ae228d0..37f8c54 100644 --- a/drivers/usb/core/Kconfig +++ b/drivers/usb/core/Kconfig @@ -41,20 +41,6 @@ config USB_DYNAMIC_MINORS If you are unsure about this, say N here. -config USB_OTG - bool "OTG support" - depends on PM - default n - help - The most notable feature of USB OTG is support for a - "Dual-Role" device, which can act as either a device - or a host. The initial role is decided by the type of - plug inserted and can be changed later when two dual - role devices talk to each other. - - Select this only if your board has Mini-AB/Micro-AB - connector. - config USB_OTG_WHITELIST bool "Rely on OTG and EH Targeted Peripherals List" depends on USB diff --git a/drivers/usb/gadget/Kconfig b/drivers/usb/gadget/Kconfig index 3c3f31c..5fc9095 100644 --- a/drivers/usb/gadget/Kconfig +++ b/drivers/usb/gadget/Kconfig @@ -16,6 +16,7 @@ menuconfig USB_GADGET tristate "USB Gadget Support" select USB_COMMON + select USB_OTG_CORE select NLS help USB is a master/slave protocol, organized with one master diff --git a/include/linux/usb/gadget.h b/include/linux/usb/gadget.h index f4fc0aa..1d74fb8 100644 --- a/include/linux/usb/gadget.h +++ b/include/linux/usb/gadget.h @@ -328,6 +328,7 @@ struct usb_gadget_ops { * @in_epnum: last used in ep number * @mA: last set mA value * @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. @@ -385,6 +386,7 @@ struct usb_gadget { unsigned in_epnum; unsigned mA; 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 7729c1f..36bd54f 100644 --- a/include/linux/usb/hcd.h +++ b/include/linux/usb/hcd.h @@ -185,6 +185,7 @@ 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..9d72951 100644 --- a/include/linux/usb/otg.h +++ b/include/linux/usb/otg.h @@ -10,10 +10,67 @@ #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/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 + * @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_caps - describes the otg capabilities of the device + * @otg_rev: The OTG revision number the device is compliant with, it's + * in binary-coded decimal (i.e. 2.0 is 0200H). + * @hnp_support: Indicates if the device supports HNP. + * @srp_support: Indicates if the device supports SRP. + * @adp_support: Indicates if the device supports ADP. + */ +struct usb_otg_caps { + u16 otg_rev; + bool hnp_support; + bool srp_support; + bool adp_support; +}; +/** + * 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 +81,25 @@ 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; + bool gadget_ready; + 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); @@ -42,26 +115,95 @@ struct usb_otg { /* start or continue HNP role switch */ int (*start_hnp)(struct usb_otg *otg); - +/*---------------------------------------------------------------*/ }; /** - * struct usb_otg_caps - describes the otg capabilities of the device - * @otg_rev: The OTG revision number the device is compliant with, it's - * in binary-coded decimal (i.e. 2.0 is 0200H). - * @hnp_support: Indicates if the device supports HNP. - * @srp_support: Indicates if the device supports SRP. - * @adp_support: Indicates if the device supports ADP. + * 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_caps { - u16 otg_rev; - bool hnp_support; - bool srp_support; - bool adp_support; +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_start_host(struct usb_otg *otg, int on); +int usb_otg_start_gadget(struct usb_otg *otg, int on); +int usb_otg_gadget_ready(struct usb_gadget *gadget, bool ready); + +#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_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; +} + +static inline int usb_otg_gadget_ready(struct usb_gadget *gadget, bool ready) +{ + return -ENOTSUPP; +} +#endif /* CONFIG_USB_OTG */ + +/*------------- deprecated interface -----------------------------*/ /* Context: can sleep */ static inline int otg_start_hnp(struct usb_otg *otg) @@ -113,6 +255,8 @@ 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 +381,6 @@ 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
