summaryrefslogtreecommitdiffstats
path: root/kernel/drivers/usb/host/whci/pzl.c
diff options
context:
space:
mode:
Diffstat (limited to 'kernel/drivers/usb/host/whci/pzl.c')
-rw-r--r--kernel/drivers/usb/host/whci/pzl.c417
1 files changed, 417 insertions, 0 deletions
diff --git a/kernel/drivers/usb/host/whci/pzl.c b/kernel/drivers/usb/host/whci/pzl.c
new file mode 100644
index 000000000..33c5580b4
--- /dev/null
+++ b/kernel/drivers/usb/host/whci/pzl.c
@@ -0,0 +1,417 @@
+/*
+ * Wireless Host Controller (WHC) periodic 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/gfp.h>
+#include <linux/dma-mapping.h>
+#include <linux/uwb/umc.h>
+#include <linux/usb.h>
+
+#include "../../wusbcore/wusbhc.h"
+
+#include "whcd.h"
+
+static void update_pzl_pointers(struct whc *whc, int period, u64 addr)
+{
+ switch (period) {
+ case 0:
+ whc_qset_set_link_ptr(&whc->pz_list[0], addr);
+ whc_qset_set_link_ptr(&whc->pz_list[2], addr);
+ whc_qset_set_link_ptr(&whc->pz_list[4], addr);
+ whc_qset_set_link_ptr(&whc->pz_list[6], addr);
+ whc_qset_set_link_ptr(&whc->pz_list[8], addr);
+ whc_qset_set_link_ptr(&whc->pz_list[10], addr);
+ whc_qset_set_link_ptr(&whc->pz_list[12], addr);
+ whc_qset_set_link_ptr(&whc->pz_list[14], addr);
+ break;
+ case 1:
+ whc_qset_set_link_ptr(&whc->pz_list[1], addr);
+ whc_qset_set_link_ptr(&whc->pz_list[5], addr);
+ whc_qset_set_link_ptr(&whc->pz_list[9], addr);
+ whc_qset_set_link_ptr(&whc->pz_list[13], addr);
+ break;
+ case 2:
+ whc_qset_set_link_ptr(&whc->pz_list[3], addr);
+ whc_qset_set_link_ptr(&whc->pz_list[11], addr);
+ break;
+ case 3:
+ whc_qset_set_link_ptr(&whc->pz_list[7], addr);
+ break;
+ case 4:
+ whc_qset_set_link_ptr(&whc->pz_list[15], addr);
+ break;
+ }
+}
+
+/*
+ * Return the 'period' to use for this qset. The minimum interval for
+ * the endpoint is used so whatever urbs are submitted the device is
+ * polled often enough.
+ */
+static int qset_get_period(struct whc *whc, struct whc_qset *qset)
+{
+ uint8_t bInterval = qset->ep->desc.bInterval;
+
+ if (bInterval < 6)
+ bInterval = 6;
+ if (bInterval > 10)
+ bInterval = 10;
+ return bInterval - 6;
+}
+
+static void qset_insert_in_sw_list(struct whc *whc, struct whc_qset *qset)
+{
+ int period;
+
+ period = qset_get_period(whc, qset);
+
+ qset_clear(whc, qset);
+ list_move(&qset->list_node, &whc->periodic_list[period]);
+ qset->in_sw_list = true;
+}
+
+static void pzl_qset_remove(struct whc *whc, struct whc_qset *qset)
+{
+ list_move(&qset->list_node, &whc->periodic_removed_list);
+ qset->in_hw_list = false;
+ qset->in_sw_list = false;
+}
+
+/**
+ * pzl_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 the schedule updates required.
+ */
+static enum whc_update pzl_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:
+ /*
+ * If there are no qTDs in this qset, remove it from the PZL.
+ */
+ if (qset->remove && qset->ntds == 0) {
+ pzl_qset_remove(whc, qset);
+ update |= WHC_UPDATE_REMOVED;
+ }
+
+ return update;
+}
+
+/**
+ * pzl_start - start the periodic schedule
+ * @whc: the WHCI host controller
+ *
+ * The PZL must be valid (e.g., all entries in the list should have
+ * the T bit set).
+ */
+void pzl_start(struct whc *whc)
+{
+ le_writeq(whc->pz_list_dma, whc->base + WUSBPERIODICLISTBASE);
+
+ whc_write_wusbcmd(whc, WUSBCMD_PERIODIC_EN, WUSBCMD_PERIODIC_EN);
+ whci_wait_for(&whc->umc->dev, whc->base + WUSBSTS,
+ WUSBSTS_PERIODIC_SCHED, WUSBSTS_PERIODIC_SCHED,
+ 1000, "start PZL");
+}
+
+/**
+ * pzl_stop - stop the periodic schedule
+ * @whc: the WHCI host controller
+ */
+void pzl_stop(struct whc *whc)
+{
+ whc_write_wusbcmd(whc, WUSBCMD_PERIODIC_EN, 0);
+ whci_wait_for(&whc->umc->dev, whc->base + WUSBSTS,
+ WUSBSTS_PERIODIC_SCHED, 0,
+ 1000, "stop PZL");
+}
+
+/**
+ * pzl_update - request a PZL 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 PZL is stopped) then the
+ * update must be skipped as the hardware may not respond to update
+ * requests.
+ */
+void pzl_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->periodic_list_wq,
+ (le_readl(whc->base + WUSBCMD) & WUSBCMD_PERIODIC_UPDATED) == 0,
+ msecs_to_jiffies(1000));
+ if (t == 0)
+ whc_hw_error(whc, "PZL update timeout");
+ }
+ mutex_unlock(&wusbhc->mutex);
+}
+
+static void update_pzl_hw_view(struct whc *whc)
+{
+ struct whc_qset *qset, *t;
+ int period;
+ u64 tmp_qh = 0;
+
+ for (period = 0; period < 5; period++) {
+ list_for_each_entry_safe(qset, t, &whc->periodic_list[period], list_node) {
+ whc_qset_set_link_ptr(&qset->qh.link, tmp_qh);
+ tmp_qh = qset->qset_dma;
+ qset->in_hw_list = true;
+ }
+ update_pzl_pointers(whc, period, tmp_qh);
+ }
+}
+
+/**
+ * scan_periodic_work - scan the PZL for qsets to process.
+ *
+ * Process each qset in the PZL in turn and then signal the WHC that
+ * the PZL has been updated.
+ *
+ * Then start, stop or update the periodic schedule as required.
+ */
+void scan_periodic_work(struct work_struct *work)
+{
+ struct whc *whc = container_of(work, struct whc, periodic_work);
+ struct whc_qset *qset, *t;
+ enum whc_update update = 0;
+ int period;
+
+ spin_lock_irq(&whc->lock);
+
+ for (period = 4; period >= 0; period--) {
+ list_for_each_entry_safe(qset, t, &whc->periodic_list[period], list_node) {
+ if (!qset->in_hw_list)
+ update |= WHC_UPDATE_ADDED;
+ update |= pzl_process_qset(whc, qset);
+ }
+ }
+
+ if (update & (WHC_UPDATE_ADDED | WHC_UPDATE_REMOVED))
+ update_pzl_hw_view(whc);
+
+ spin_unlock_irq(&whc->lock);
+
+ if (update) {
+ uint32_t wusbcmd = WUSBCMD_PERIODIC_UPDATED | WUSBCMD_PERIODIC_SYNCED_DB;
+ if (update & WHC_UPDATE_REMOVED)
+ wusbcmd |= WUSBCMD_PERIODIC_QSET_RM;
+ pzl_update(whc, wusbcmd);
+ }
+
+ /*
+ * Now that the PZL is updated, complete the removal of any
+ * removed qsets.
+ *
+ * If the qset was to be reset, do so and reinsert it into the
+ * PZL if it has pending transfers.
+ */
+ spin_lock_irq(&whc->lock);
+
+ list_for_each_entry_safe(qset, t, &whc->periodic_removed_list, list_node) {
+ qset_remove_complete(whc, qset);
+ if (qset->reset) {
+ qset_reset(whc, qset);
+ if (!list_empty(&qset->stds)) {
+ qset_insert_in_sw_list(whc, qset);
+ queue_work(whc->workqueue, &whc->periodic_work);
+ }
+ }
+ }
+
+ spin_unlock_irq(&whc->lock);
+}
+
+/**
+ * pzl_urb_enqueue - queue an URB onto the periodic list (PZL)
+ * @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 PZL.
+ */
+int pzl_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)
+ qset_insert_in_sw_list(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->periodic_work);
+
+ return err;
+}
+
+/**
+ * pzl_urb_dequeue - remove an URB (qset) from the periodic 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 so the qTDs can be safely
+ * removed.
+ */
+int pzl_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) {
+ pzl_qset_remove(whc, qset);
+ update_pzl_hw_view(whc);
+ wurb->status = status;
+ wurb->is_async = false;
+ queue_work(whc->workqueue, &wurb->dequeue_work);
+ } else
+ qset_remove_urb(whc, qset, urb, status);
+out:
+ spin_unlock_irqrestore(&whc->lock, flags);
+
+ return ret;
+}
+
+/**
+ * pzl_qset_delete - delete a qset from the PZL
+ */
+void pzl_qset_delete(struct whc *whc, struct whc_qset *qset)
+{
+ qset->remove = 1;
+ queue_work(whc->workqueue, &whc->periodic_work);
+ qset_delete(whc, qset);
+}
+
+/**
+ * pzl_init - initialize the periodic zone list
+ * @whc: the WHCI host controller
+ */
+int pzl_init(struct whc *whc)
+{
+ int i;
+
+ whc->pz_list = dma_alloc_coherent(&whc->umc->dev, sizeof(u64) * 16,
+ &whc->pz_list_dma, GFP_KERNEL);
+ if (whc->pz_list == NULL)
+ return -ENOMEM;
+
+ /* Set T bit on all elements in PZL. */
+ for (i = 0; i < 16; i++)
+ whc->pz_list[i] = cpu_to_le64(QH_LINK_NTDS(8) | QH_LINK_T);
+
+ le_writeq(whc->pz_list_dma, whc->base + WUSBPERIODICLISTBASE);
+
+ return 0;
+}
+
+/**
+ * pzl_clean_up - free PZL resources
+ * @whc: the WHCI host controller
+ *
+ * The PZL is stopped and empty.
+ */
+void pzl_clean_up(struct whc *whc)
+{
+ if (whc->pz_list)
+ dma_free_coherent(&whc->umc->dev, sizeof(u64) * 16, whc->pz_list,
+ whc->pz_list_dma);
+}