1 files changed, 367 insertions, 0 deletions

diff --git a/drivers/usb/host/whci/asl.c b/drivers/usb/host/whci/asl.c
new file mode 100644
index 00000000000..4d7078e5057
--- /dev/null
+++ b/drivers/usb/host/whci/asl.c
@@ -0,0 +1,367 @@
+/*
+ * 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 <http://www.gnu.org/licenses/>.
+ */
+#include <linux/kernel.h>
+#include <linux/dma-mapping.h>
+#include <linux/uwb/umc.h>
+#include <linux/usb.h>
+#define D_LOCAL 0
+#include <linux/uwb/debug.h>
+
+#include "../../wusbcore/wusbhc.h"
+
+#include "whcd.h"
+
+#if D_LOCAL >= 4
+static void dump_asl(struct whc *whc, const char *tag)
+{
+        struct device *dev = &whc->umc->dev;
+        struct whc_qset *qset;
+
+        d_printf(4, dev, "ASL %s\n", tag);
+
+        list_for_each_entry(qset, &whc->async_list, list_node) {
+                dump_qset(qset, dev);
+        }
+}
+#else
+static inline void dump_asl(struct whc *whc, const char *tag)
+{
+}
+#endif
+
+
+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);
+                        goto done;
+                }
+
+                /* Mmm, a completed qTD. */
+                process_inactive_qtd(whc, qset, td);
+        }
+
+        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");
+}
+
+void asl_update(struct whc *whc, uint32_t wusbcmd)
+{
+        whc_write_wusbcmd(whc, wusbcmd, wusbcmd);
+        wait_event(whc->async_list_wq,
+                   (le_readl(whc->base + WUSBCMD) & WUSBCMD_ASYNC_UPDATED) == 0);
+}
+
+/**
+ * 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);
+
+        dump_asl(whc, "before processing");
+
+        /*
+         * 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);
+        }
+
+        dump_asl(whc, "after processing");
+
+        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.
+         */
+        spin_lock(&whc->lock);
+
+        list_for_each_entry_safe(qset, t, &whc->async_removed_list, list_node) {
+                qset_remove_complete(whc, qset);
+        }
+
+        spin_unlock(&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);
+
+        qset = get_qset(whc, urb, GFP_ATOMIC);
+        if (qset == NULL)
+                err = -ENOMEM;
+        else
+                err = qset_add_urb(whc, qset, urb, GFP_ATOMIC);
+        if (!err) {
+                usb_hcd_link_urb_to_ep(&whc->wusbhc.usb_hcd, urb);
+                if (!qset->in_sw_list)
+                        asl_qset_insert_begin(whc, qset);
+        }
+
+        spin_unlock_irqrestore(&whc->lock, flags);
+
+        if (!err)
+                queue_work(whc->workqueue, &whc->async_work);
+
+        return 0;
+}
+
+/**
+ * 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;
+        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)
+                        qset_free_std(whc, std);
+                else
+                        std->qtd = NULL; /* so this std is re-added when the qset is */
+        }
+
+        asl_qset_remove(whc, qset);
+        wurb->status = status;
+        wurb->is_async = true;
+        queue_work(whc->workqueue, &wurb->dequeue_work);
+
+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);
+        }
+}