From 57f0f512b273f60d52568b8c6b77e17f5636edc0 Mon Sep 17 00:00:00 2001 From: André Fabian Silva Delgado Date: Wed, 5 Aug 2015 17:04:01 -0300 Subject: Initial import --- drivers/usb/host/whci/asl.c | 389 ++++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 389 insertions(+) create mode 100644 drivers/usb/host/whci/asl.c (limited to 'drivers/usb/host/whci/asl.c') diff --git a/drivers/usb/host/whci/asl.c b/drivers/usb/host/whci/asl.c new file mode 100644 index 000000000..773249306 --- /dev/null +++ b/drivers/usb/host/whci/asl.c @@ -0,0 +1,389 @@ +/* + * Wireless Host Controller (WHC) asynchronous schedule management. + * + * Copyright (C) 2007 Cambridge Silicon Radio Ltd. + * + * 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. + * + * You should have received a copy of the GNU General Public License + * along with this program. If not, see . + */ +#include +#include +#include +#include +#include + +#include "../../wusbcore/wusbhc.h" + +#include "whcd.h" + +static void qset_get_next_prev(struct whc *whc, struct whc_qset *qset, + struct whc_qset **next, struct whc_qset **prev) +{ + struct list_head *n, *p; + + BUG_ON(list_empty(&whc->async_list)); + + n = qset->list_node.next; + if (n == &whc->async_list) + n = n->next; + p = qset->list_node.prev; + if (p == &whc->async_list) + p = p->prev; + + *next = container_of(n, struct whc_qset, list_node); + *prev = container_of(p, struct whc_qset, list_node); + +} + +static void asl_qset_insert_begin(struct whc *whc, struct whc_qset *qset) +{ + list_move(&qset->list_node, &whc->async_list); + qset->in_sw_list = true; +} + +static void asl_qset_insert(struct whc *whc, struct whc_qset *qset) +{ + struct whc_qset *next, *prev; + + qset_clear(whc, qset); + + /* Link into ASL. */ + qset_get_next_prev(whc, qset, &next, &prev); + whc_qset_set_link_ptr(&qset->qh.link, next->qset_dma); + whc_qset_set_link_ptr(&prev->qh.link, qset->qset_dma); + qset->in_hw_list = true; +} + +static void asl_qset_remove(struct whc *whc, struct whc_qset *qset) +{ + struct whc_qset *prev, *next; + + qset_get_next_prev(whc, qset, &next, &prev); + + list_move(&qset->list_node, &whc->async_removed_list); + qset->in_sw_list = false; + + /* + * No more qsets in the ASL? The caller must stop the ASL as + * it's no longer valid. + */ + if (list_empty(&whc->async_list)) + return; + + /* Remove from ASL. */ + whc_qset_set_link_ptr(&prev->qh.link, next->qset_dma); + qset->in_hw_list = false; +} + +/** + * process_qset - process any recently inactivated or halted qTDs in a + * qset. + * + * After inactive qTDs are removed, new qTDs can be added if the + * urb queue still contains URBs. + * + * Returns any additional WUSBCMD bits for the ASL sync command (i.e., + * WUSBCMD_ASYNC_QSET_RM if a halted qset was removed). + */ +static uint32_t process_qset(struct whc *whc, struct whc_qset *qset) +{ + enum whc_update update = 0; + uint32_t status = 0; + + while (qset->ntds) { + struct whc_qtd *td; + int t; + + t = qset->td_start; + td = &qset->qtd[qset->td_start]; + status = le32_to_cpu(td->status); + + /* + * Nothing to do with a still active qTD. + */ + if (status & QTD_STS_ACTIVE) + break; + + if (status & QTD_STS_HALTED) { + /* Ug, an error. */ + process_halted_qtd(whc, qset, td); + /* A halted qTD always triggers an update + because the qset was either removed or + reactivated. */ + update |= WHC_UPDATE_UPDATED; + goto done; + } + + /* Mmm, a completed qTD. */ + process_inactive_qtd(whc, qset, td); + } + + if (!qset->remove) + update |= qset_add_qtds(whc, qset); + +done: + /* + * Remove this qset from the ASL if requested, but only if has + * no qTDs. + */ + if (qset->remove && qset->ntds == 0) { + asl_qset_remove(whc, qset); + update |= WHC_UPDATE_REMOVED; + } + return update; +} + +void asl_start(struct whc *whc) +{ + struct whc_qset *qset; + + qset = list_first_entry(&whc->async_list, struct whc_qset, list_node); + + le_writeq(qset->qset_dma | QH_LINK_NTDS(8), whc->base + WUSBASYNCLISTADDR); + + whc_write_wusbcmd(whc, WUSBCMD_ASYNC_EN, WUSBCMD_ASYNC_EN); + whci_wait_for(&whc->umc->dev, whc->base + WUSBSTS, + WUSBSTS_ASYNC_SCHED, WUSBSTS_ASYNC_SCHED, + 1000, "start ASL"); +} + +void asl_stop(struct whc *whc) +{ + whc_write_wusbcmd(whc, WUSBCMD_ASYNC_EN, 0); + whci_wait_for(&whc->umc->dev, whc->base + WUSBSTS, + WUSBSTS_ASYNC_SCHED, 0, + 1000, "stop ASL"); +} + +/** + * asl_update - request an ASL update and wait for the hardware to be synced + * @whc: the WHCI HC + * @wusbcmd: WUSBCMD value to start the update. + * + * If the WUSB HC is inactive (i.e., the ASL is stopped) then the + * update must be skipped as the hardware may not respond to update + * requests. + */ +void asl_update(struct whc *whc, uint32_t wusbcmd) +{ + struct wusbhc *wusbhc = &whc->wusbhc; + long t; + + mutex_lock(&wusbhc->mutex); + if (wusbhc->active) { + whc_write_wusbcmd(whc, wusbcmd, wusbcmd); + t = wait_event_timeout( + whc->async_list_wq, + (le_readl(whc->base + WUSBCMD) & WUSBCMD_ASYNC_UPDATED) == 0, + msecs_to_jiffies(1000)); + if (t == 0) + whc_hw_error(whc, "ASL update timeout"); + } + mutex_unlock(&wusbhc->mutex); +} + +/** + * scan_async_work - scan the ASL for qsets to process. + * + * Process each qset in the ASL in turn and then signal the WHC that + * the ASL has been updated. + * + * Then start, stop or update the asynchronous schedule as required. + */ +void scan_async_work(struct work_struct *work) +{ + struct whc *whc = container_of(work, struct whc, async_work); + struct whc_qset *qset, *t; + enum whc_update update = 0; + + spin_lock_irq(&whc->lock); + + /* + * Transerve the software list backwards so new qsets can be + * safely inserted into the ASL without making it non-circular. + */ + list_for_each_entry_safe_reverse(qset, t, &whc->async_list, list_node) { + if (!qset->in_hw_list) { + asl_qset_insert(whc, qset); + update |= WHC_UPDATE_ADDED; + } + + update |= process_qset(whc, qset); + } + + spin_unlock_irq(&whc->lock); + + if (update) { + uint32_t wusbcmd = WUSBCMD_ASYNC_UPDATED | WUSBCMD_ASYNC_SYNCED_DB; + if (update & WHC_UPDATE_REMOVED) + wusbcmd |= WUSBCMD_ASYNC_QSET_RM; + asl_update(whc, wusbcmd); + } + + /* + * Now that the ASL is updated, complete the removal of any + * removed qsets. + * + * If the qset was to be reset, do so and reinsert it into the + * ASL if it has pending transfers. + */ + spin_lock_irq(&whc->lock); + + list_for_each_entry_safe(qset, t, &whc->async_removed_list, list_node) { + qset_remove_complete(whc, qset); + if (qset->reset) { + qset_reset(whc, qset); + if (!list_empty(&qset->stds)) { + asl_qset_insert_begin(whc, qset); + queue_work(whc->workqueue, &whc->async_work); + } + } + } + + spin_unlock_irq(&whc->lock); +} + +/** + * asl_urb_enqueue - queue an URB onto the asynchronous list (ASL). + * @whc: the WHCI host controller + * @urb: the URB to enqueue + * @mem_flags: flags for any memory allocations + * + * The qset for the endpoint is obtained and the urb queued on to it. + * + * Work is scheduled to update the hardware's view of the ASL. + */ +int asl_urb_enqueue(struct whc *whc, struct urb *urb, gfp_t mem_flags) +{ + struct whc_qset *qset; + int err; + unsigned long flags; + + spin_lock_irqsave(&whc->lock, flags); + + err = usb_hcd_link_urb_to_ep(&whc->wusbhc.usb_hcd, urb); + if (err < 0) { + spin_unlock_irqrestore(&whc->lock, flags); + return err; + } + + qset = get_qset(whc, urb, GFP_ATOMIC); + if (qset == NULL) + err = -ENOMEM; + else + err = qset_add_urb(whc, qset, urb, GFP_ATOMIC); + if (!err) { + if (!qset->in_sw_list && !qset->remove) + asl_qset_insert_begin(whc, qset); + } else + usb_hcd_unlink_urb_from_ep(&whc->wusbhc.usb_hcd, urb); + + spin_unlock_irqrestore(&whc->lock, flags); + + if (!err) + queue_work(whc->workqueue, &whc->async_work); + + return err; +} + +/** + * asl_urb_dequeue - remove an URB (qset) from the async list. + * @whc: the WHCI host controller + * @urb: the URB to dequeue + * @status: the current status of the URB + * + * URBs that do yet have qTDs can simply be removed from the software + * queue, otherwise the qset must be removed from the ASL so the qTDs + * can be removed. + */ +int asl_urb_dequeue(struct whc *whc, struct urb *urb, int status) +{ + struct whc_urb *wurb = urb->hcpriv; + struct whc_qset *qset = wurb->qset; + struct whc_std *std, *t; + bool has_qtd = false; + int ret; + unsigned long flags; + + spin_lock_irqsave(&whc->lock, flags); + + ret = usb_hcd_check_unlink_urb(&whc->wusbhc.usb_hcd, urb, status); + if (ret < 0) + goto out; + + list_for_each_entry_safe(std, t, &qset->stds, list_node) { + if (std->urb == urb) { + if (std->qtd) + has_qtd = true; + qset_free_std(whc, std); + } else + std->qtd = NULL; /* so this std is re-added when the qset is */ + } + + if (has_qtd) { + asl_qset_remove(whc, qset); + wurb->status = status; + wurb->is_async = true; + queue_work(whc->workqueue, &wurb->dequeue_work); + } else + qset_remove_urb(whc, qset, urb, status); +out: + spin_unlock_irqrestore(&whc->lock, flags); + + return ret; +} + +/** + * asl_qset_delete - delete a qset from the ASL + */ +void asl_qset_delete(struct whc *whc, struct whc_qset *qset) +{ + qset->remove = 1; + queue_work(whc->workqueue, &whc->async_work); + qset_delete(whc, qset); +} + +/** + * asl_init - initialize the asynchronous schedule list + * + * A dummy qset with no qTDs is added to the ASL to simplify removing + * qsets (no need to stop the ASL when the last qset is removed). + */ +int asl_init(struct whc *whc) +{ + struct whc_qset *qset; + + qset = qset_alloc(whc, GFP_KERNEL); + if (qset == NULL) + return -ENOMEM; + + asl_qset_insert_begin(whc, qset); + asl_qset_insert(whc, qset); + + return 0; +} + +/** + * asl_clean_up - free ASL resources + * + * The ASL is stopped and empty except for the dummy qset. + */ +void asl_clean_up(struct whc *whc) +{ + struct whc_qset *qset; + + if (!list_empty(&whc->async_list)) { + qset = list_first_entry(&whc->async_list, struct whc_qset, list_node); + list_del(&qset->list_node); + qset_free(whc, qset); + } +} -- cgit v1.2.3-54-g00ecf