// SPDX-License-Identifier: GPL-2.0 /* * Cadence USBSS and USBSSP DRD Driver. * * Copyright (C) 2018-2019 Cadence. * Copyright (C) 2017-2018 NXP * Copyright (C) 2019 Texas Instruments * * Author: Peter Chen * Pawel Laszczak * Roger Quadros */ #include #include #include #include #include #include #include #include #include "core.h" #include "host-export.h" #include "drd.h" static int cdns_idle_init(struct cdns *cdns); static int cdns_role_start(struct cdns *cdns, enum usb_role role) { int ret; if (WARN_ON(role > USB_ROLE_DEVICE)) return 0; mutex_lock(&cdns->mutex); cdns->role = role; mutex_unlock(&cdns->mutex); if (!cdns->roles[role]) return -ENXIO; if (cdns->roles[role]->state == CDNS_ROLE_STATE_ACTIVE) return 0; mutex_lock(&cdns->mutex); ret = cdns->roles[role]->start(cdns); if (!ret) cdns->roles[role]->state = CDNS_ROLE_STATE_ACTIVE; mutex_unlock(&cdns->mutex); return ret; } static void cdns_role_stop(struct cdns *cdns) { enum usb_role role = cdns->role; if (WARN_ON(role > USB_ROLE_DEVICE)) return; if (cdns->roles[role]->state == CDNS_ROLE_STATE_INACTIVE) return; mutex_lock(&cdns->mutex); cdns->roles[role]->stop(cdns); cdns->roles[role]->state = CDNS_ROLE_STATE_INACTIVE; mutex_unlock(&cdns->mutex); } static void cdns_exit_roles(struct cdns *cdns) { cdns_role_stop(cdns); cdns_drd_exit(cdns); } /** * cdns_core_init_role - initialize role of operation * @cdns: Pointer to cdns structure * * Returns 0 on success otherwise negative errno */ static int cdns_core_init_role(struct cdns *cdns) { struct device *dev = cdns->dev; enum usb_dr_mode best_dr_mode; enum usb_dr_mode dr_mode; int ret; dr_mode = usb_get_dr_mode(dev); cdns->role = USB_ROLE_NONE; /* * If driver can't read mode by means of usb_get_dr_mode function then * chooses mode according with Kernel configuration. This setting * can be restricted later depending on strap pin configuration. */ if (dr_mode == USB_DR_MODE_UNKNOWN) { if (cdns->version == CDNSP_CONTROLLER_V2) { if (IS_ENABLED(CONFIG_USB_CDNSP_HOST) && IS_ENABLED(CONFIG_USB_CDNSP_GADGET)) dr_mode = USB_DR_MODE_OTG; else if (IS_ENABLED(CONFIG_USB_CDNSP_HOST)) dr_mode = USB_DR_MODE_HOST; else if (IS_ENABLED(CONFIG_USB_CDNSP_GADGET)) dr_mode = USB_DR_MODE_PERIPHERAL; } else { if (IS_ENABLED(CONFIG_USB_CDNS3_HOST) && IS_ENABLED(CONFIG_USB_CDNS3_GADGET)) dr_mode = USB_DR_MODE_OTG; else if (IS_ENABLED(CONFIG_USB_CDNS3_HOST)) dr_mode = USB_DR_MODE_HOST; else if (IS_ENABLED(CONFIG_USB_CDNS3_GADGET)) dr_mode = USB_DR_MODE_PERIPHERAL; } } /* * At this point cdns->dr_mode contains strap configuration. * Driver try update this setting considering kernel configuration */ best_dr_mode = cdns->dr_mode; ret = cdns_idle_init(cdns); if (ret) return ret; if (dr_mode == USB_DR_MODE_OTG) { best_dr_mode = cdns->dr_mode; } else if (cdns->dr_mode == USB_DR_MODE_OTG) { best_dr_mode = dr_mode; } else if (cdns->dr_mode != dr_mode) { dev_err(dev, "Incorrect DRD configuration\n"); return -EINVAL; } dr_mode = best_dr_mode; if (dr_mode == USB_DR_MODE_OTG || dr_mode == USB_DR_MODE_HOST) { if ((cdns->version == CDNSP_CONTROLLER_V2 && IS_ENABLED(CONFIG_USB_CDNSP_HOST)) || (cdns->version < CDNSP_CONTROLLER_V2 && IS_ENABLED(CONFIG_USB_CDNS3_HOST))) ret = cdns_host_init(cdns); else ret = -ENXIO; if (ret) { dev_err(dev, "Host initialization failed with %d\n", ret); goto err; } } if (dr_mode == USB_DR_MODE_OTG || dr_mode == USB_DR_MODE_PERIPHERAL) { if (cdns->gadget_init) ret = cdns->gadget_init(cdns); else ret = -ENXIO; if (ret) { dev_err(dev, "Device initialization failed with %d\n", ret); goto err; } } cdns->dr_mode = dr_mode; ret = cdns_drd_update_mode(cdns); if (ret) goto err; /* Initialize idle role to start with */ ret = cdns_role_start(cdns, USB_ROLE_NONE); if (ret) goto err; switch (cdns->dr_mode) { case USB_DR_MODE_OTG: ret = cdns_hw_role_switch(cdns); if (ret) goto err; break; case USB_DR_MODE_PERIPHERAL: ret = cdns_role_start(cdns, USB_ROLE_DEVICE); if (ret) goto err; break; case USB_DR_MODE_HOST: ret = cdns_role_start(cdns, USB_ROLE_HOST); if (ret) goto err; break; default: ret = -EINVAL; goto err; } return 0; err: cdns_exit_roles(cdns); return ret; } /** * cdns_hw_role_state_machine - role switch state machine based on hw events. * @cdns: Pointer to controller structure. * * Returns next role to be entered based on hw events. */ static enum usb_role cdns_hw_role_state_machine(struct cdns *cdns) { enum usb_role role = USB_ROLE_NONE; int id, vbus; if (cdns->dr_mode != USB_DR_MODE_OTG) { if (cdns_is_host(cdns)) role = USB_ROLE_HOST; if (cdns_is_device(cdns)) role = USB_ROLE_DEVICE; return role; } id = cdns_get_id(cdns); vbus = cdns_get_vbus(cdns); /* * Role change state machine * Inputs: ID, VBUS * Previous state: cdns->role * Next state: role */ role = cdns->role; switch (role) { case USB_ROLE_NONE: /* * Driver treats USB_ROLE_NONE synonymous to IDLE state from * controller specification. */ if (!id) role = USB_ROLE_HOST; else if (vbus) role = USB_ROLE_DEVICE; break; case USB_ROLE_HOST: /* from HOST, we can only change to NONE */ if (id) role = USB_ROLE_NONE; break; case USB_ROLE_DEVICE: /* from GADGET, we can only change to NONE*/ if (!vbus) role = USB_ROLE_NONE; break; } dev_dbg(cdns->dev, "role %d -> %d\n", cdns->role, role); return role; } static int cdns_idle_role_start(struct cdns *cdns) { return 0; } static void cdns_idle_role_stop(struct cdns *cdns) { /* Program Lane swap and bring PHY out of RESET */ phy_reset(cdns->usb3_phy); } static int cdns_idle_init(struct cdns *cdns) { struct cdns_role_driver *rdrv; rdrv = devm_kzalloc(cdns->dev, sizeof(*rdrv), GFP_KERNEL); if (!rdrv) return -ENOMEM; rdrv->start = cdns_idle_role_start; rdrv->stop = cdns_idle_role_stop; rdrv->state = CDNS_ROLE_STATE_INACTIVE; rdrv->suspend = NULL; rdrv->resume = NULL; rdrv->name = "idle"; cdns->roles[USB_ROLE_NONE] = rdrv; return 0; } /** * cdns_hw_role_switch - switch roles based on HW state * @cdns: controller */ int cdns_hw_role_switch(struct cdns *cdns) { enum usb_role real_role, current_role; int ret = 0; /* Depends on role switch class */ if (cdns->role_sw) return 0; pm_runtime_get_sync(cdns->dev); current_role = cdns->role; real_role = cdns_hw_role_state_machine(cdns); /* Do nothing if nothing changed */ if (current_role == real_role) goto exit; cdns_role_stop(cdns); dev_dbg(cdns->dev, "Switching role %d -> %d", current_role, real_role); ret = cdns_role_start(cdns, real_role); if (ret) { /* Back to current role */ dev_err(cdns->dev, "set %d has failed, back to %d\n", real_role, current_role); ret = cdns_role_start(cdns, current_role); if (ret) dev_err(cdns->dev, "back to %d failed too\n", current_role); } exit: pm_runtime_put_sync(cdns->dev); return ret; } /** * cdns_role_get - get current role of controller. * * @sw: pointer to USB role switch structure * * Returns role */ static enum usb_role cdns_role_get(struct usb_role_switch *sw) { struct cdns *cdns = usb_role_switch_get_drvdata(sw); return cdns->role; } /** * cdns_role_set - set current role of controller. * * @sw: pointer to USB role switch structure * @role: the previous role * Handles below events: * - Role switch for dual-role devices * - USB_ROLE_GADGET <--> USB_ROLE_NONE for peripheral-only devices */ static int cdns_role_set(struct usb_role_switch *sw, enum usb_role role) { struct cdns *cdns = usb_role_switch_get_drvdata(sw); int ret = 0; pm_runtime_get_sync(cdns->dev); if (cdns->role == role) goto pm_put; if (cdns->dr_mode == USB_DR_MODE_HOST) { switch (role) { case USB_ROLE_NONE: case USB_ROLE_HOST: break; default: goto pm_put; } } if (cdns->dr_mode == USB_DR_MODE_PERIPHERAL) { switch (role) { case USB_ROLE_NONE: case USB_ROLE_DEVICE: break; default: goto pm_put; } } cdns_role_stop(cdns); ret = cdns_role_start(cdns, role); if (ret) dev_err(cdns->dev, "set role %d has failed\n", role); pm_put: pm_runtime_put_sync(cdns->dev); return ret; } /** * cdns_wakeup_irq - interrupt handler for wakeup events * @irq: irq number for cdns3/cdnsp core device * @data: structure of cdns * * Returns IRQ_HANDLED or IRQ_NONE */ static irqreturn_t cdns_wakeup_irq(int irq, void *data) { struct cdns *cdns = data; if (cdns->in_lpm) { disable_irq_nosync(irq); cdns->wakeup_pending = true; if ((cdns->role == USB_ROLE_HOST) && cdns->host_dev) pm_request_resume(&cdns->host_dev->dev); return IRQ_HANDLED; } return IRQ_NONE; } /** * cdns_init - probe for cdns3/cdnsp core device * @cdns: Pointer to cdns structure. * * Returns 0 on success otherwise negative errno */ int cdns_init(struct cdns *cdns) { struct device *dev = cdns->dev; int ret; ret = dma_set_mask_and_coherent(dev, DMA_BIT_MASK(32)); if (ret) { dev_err(dev, "error setting dma mask: %d\n", ret); return ret; } mutex_init(&cdns->mutex); if (device_property_read_bool(dev, "usb-role-switch")) { struct usb_role_switch_desc sw_desc = { }; sw_desc.set = cdns_role_set; sw_desc.get = cdns_role_get; sw_desc.allow_userspace_control = true; sw_desc.driver_data = cdns; sw_desc.fwnode = dev->fwnode; cdns->role_sw = usb_role_switch_register(dev, &sw_desc); if (IS_ERR(cdns->role_sw)) { dev_warn(dev, "Unable to register Role Switch\n"); return PTR_ERR(cdns->role_sw); } } if (cdns->wakeup_irq) { ret = devm_request_irq(cdns->dev, cdns->wakeup_irq, cdns_wakeup_irq, IRQF_SHARED, dev_name(cdns->dev), cdns); if (ret) { dev_err(cdns->dev, "couldn't register wakeup irq handler\n"); goto role_switch_unregister; } } ret = cdns_drd_init(cdns); if (ret) goto init_failed; ret = cdns_core_init_role(cdns); if (ret) goto init_failed; spin_lock_init(&cdns->lock); dev_dbg(dev, "Cadence USB3 core: probe succeed\n"); return 0; init_failed: cdns_drd_exit(cdns); role_switch_unregister: if (cdns->role_sw) usb_role_switch_unregister(cdns->role_sw); return ret; } EXPORT_SYMBOL_GPL(cdns_init); /** * cdns_remove - unbind drd driver and clean up * @cdns: Pointer to cdns structure. * * Returns 0 on success otherwise negative errno */ int cdns_remove(struct cdns *cdns) { cdns_exit_roles(cdns); usb_role_switch_unregister(cdns->role_sw); return 0; } EXPORT_SYMBOL_GPL(cdns_remove); #ifdef CONFIG_PM_SLEEP int cdns_suspend(struct cdns *cdns) { struct device *dev = cdns->dev; unsigned long flags; if (pm_runtime_status_suspended(dev)) pm_runtime_resume(dev); if (cdns->roles[cdns->role]->suspend) { spin_lock_irqsave(&cdns->lock, flags); cdns->roles[cdns->role]->suspend(cdns, false); spin_unlock_irqrestore(&cdns->lock, flags); } return 0; } EXPORT_SYMBOL_GPL(cdns_suspend); int cdns_resume(struct cdns *cdns) { enum usb_role real_role; bool role_changed = false; int ret = 0; if (cdns_power_is_lost(cdns)) { if (cdns->role_sw) { cdns->role = cdns_role_get(cdns->role_sw); } else { real_role = cdns_hw_role_state_machine(cdns); if (real_role != cdns->role) { ret = cdns_hw_role_switch(cdns); if (ret) return ret; role_changed = true; } } if (!role_changed) { if (cdns->role == USB_ROLE_HOST) ret = cdns_drd_host_on(cdns); else if (cdns->role == USB_ROLE_DEVICE) ret = cdns_drd_gadget_on(cdns); if (ret) return ret; } } if (cdns->roles[cdns->role]->resume) cdns->roles[cdns->role]->resume(cdns, cdns_power_is_lost(cdns)); return 0; } EXPORT_SYMBOL_GPL(cdns_resume); void cdns_set_active(struct cdns *cdns, u8 set_active) { struct device *dev = cdns->dev; if (set_active) { pm_runtime_disable(dev); pm_runtime_set_active(dev); pm_runtime_enable(dev); } return; } EXPORT_SYMBOL_GPL(cdns_set_active); #endif /* CONFIG_PM_SLEEP */ MODULE_AUTHOR("Peter Chen "); MODULE_AUTHOR("Pawel Laszczak "); MODULE_AUTHOR("Roger Quadros "); MODULE_DESCRIPTION("Cadence USBSS and USBSSP DRD Driver"); MODULE_LICENSE("GPL");