usb/isp1760: Fix possible unlink problems

Use skip map to avoid spurious interrupts from unlinked transfers.
Also changes to urb_dequeue() and endpoint_disable() to avoid
release of spinlock in uncertain state.

Signed-off-by: Arvid Brodin <arvid.brodin@enea.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>

1 files changed, 95 insertions, 52 deletions

diff --git a/drivers/usb/host/isp1760-hcd.c b/drivers/usb/host/isp1760-hcd.c
index 485fc70625a1..c9e6e454c625 100644
--- a/drivers/usb/host/isp1760-hcd.c
+++ b/drivers/usb/host/isp1760-hcd.c
@@ -34,7 +34,9 @@ struct isp1760_hcd {
         u32 hcs_params;
         spinlock_t              lock;
         struct slotinfo         atl_slots[32];
+        int                     atl_done_map;
         struct slotinfo         int_slots[32];
+        int                     int_done_map;
         struct memory_chunk memory_pool[BLOCKS];
         struct list_head        controlqhs, bulkqhs, interruptqhs;
         int active_ptds;
@@ -519,9 +521,9 @@ static void isp1760_init_maps(struct usb_hcd *hcd)
         reg_write32(hcd->regs, HC_INT_PTD_LASTPTD_REG, 0x80000000);
         reg_write32(hcd->regs, HC_ISO_PTD_LASTPTD_REG, 0x00000001);
 
-        reg_write32(hcd->regs, HC_ATL_PTD_SKIPMAP_REG, 0);
-        reg_write32(hcd->regs, HC_INT_PTD_SKIPMAP_REG, 0);
-        reg_write32(hcd->regs, HC_ISO_PTD_SKIPMAP_REG, 0);
+        reg_write32(hcd->regs, HC_ATL_PTD_SKIPMAP_REG, 0xffffffff);
+        reg_write32(hcd->regs, HC_INT_PTD_SKIPMAP_REG, 0xffffffff);
+        reg_write32(hcd->regs, HC_ISO_PTD_SKIPMAP_REG, 0xffffffff);
 
         reg_write32(hcd->regs, HC_BUFFER_STATUS_REG,
                                                 ATL_BUF_FILL | INT_BUF_FILL);
@@ -803,6 +805,8 @@ static void start_bus_transfer(struct usb_hcd *hcd, u32 ptd_offset, int slot,
                                 struct isp1760_qh *qh, struct ptd *ptd)
 {
         struct isp1760_hcd *priv = hcd_to_priv(hcd);
+        int skip_map;
+
         WARN_ON((slot < 0) || (slot > 31));
         WARN_ON(qtd->length && !qtd->payload_addr);
         WARN_ON(slots[slot].qtd);
@@ -816,6 +820,25 @@ static void start_bus_transfer(struct usb_hcd *hcd, u32 ptd_offset, int slot,
                 interrupt routine may preempt and expects this value. */
         ptd_write(hcd->regs, ptd_offset, slot, ptd);
         priv->active_ptds++;
+
+        /* Make sure done map has not triggered from some unlinked transfer */
+        if (ptd_offset == ATL_PTD_OFFSET) {
+                priv->atl_done_map |= reg_read32(hcd->regs,
+                                                HC_ATL_PTD_DONEMAP_REG);
+                priv->atl_done_map &= ~(1 << qh->slot);
+
+                skip_map = reg_read32(hcd->regs, HC_ATL_PTD_SKIPMAP_REG);
+                skip_map &= ~(1 << qh->slot);
+                reg_write32(hcd->regs, HC_ATL_PTD_SKIPMAP_REG, skip_map);
+        } else {
+                priv->int_done_map |= reg_read32(hcd->regs,
+                                                HC_INT_PTD_DONEMAP_REG);
+                priv->int_done_map &= ~(1 << qh->slot);
+
+                skip_map = reg_read32(hcd->regs, HC_INT_PTD_SKIPMAP_REG);
+                skip_map &= ~(1 << qh->slot);
+                reg_write32(hcd->regs, HC_INT_PTD_SKIPMAP_REG, skip_map);
+        }
 }
 
 static int is_short_bulk(struct isp1760_qtd *qtd)
@@ -1152,7 +1175,6 @@ static irqreturn_t isp1760_irq(struct usb_hcd *hcd)
         irqreturn_t irqret = IRQ_NONE;
         struct ptd ptd;
         struct isp1760_qh *qh;
-        int int_done_map, atl_done_map;
         int slot;
         int state;
         struct slotinfo *slots;
@@ -1160,6 +1182,7 @@ static irqreturn_t isp1760_irq(struct usb_hcd *hcd)
         struct isp1760_qtd *qtd;
         int modified;
         static int last_active_ptds;
+        int int_skip_map, atl_skip_map;
 
         spin_lock(&priv->lock);
 
@@ -1171,29 +1194,42 @@ static irqreturn_t isp1760_irq(struct usb_hcd *hcd)
                 goto leave;
         reg_write32(hcd->regs, HC_INTERRUPT_REG, imask); /* Clear */
 
-        int_done_map = reg_read32(hcd->regs, HC_INT_PTD_DONEMAP_REG);
-        atl_done_map = reg_read32(hcd->regs, HC_ATL_PTD_DONEMAP_REG);
-        modified = int_done_map | atl_done_map;
+        int_skip_map = reg_read32(hcd->regs, HC_INT_PTD_SKIPMAP_REG);
+        atl_skip_map = reg_read32(hcd->regs, HC_ATL_PTD_SKIPMAP_REG);
+        priv->int_done_map |= reg_read32(hcd->regs, HC_INT_PTD_DONEMAP_REG);
+        priv->atl_done_map |= reg_read32(hcd->regs, HC_ATL_PTD_DONEMAP_REG);
+        priv->int_done_map &= ~int_skip_map;
+        priv->atl_done_map &= ~atl_skip_map;
 
-        while (int_done_map || atl_done_map) {
-                if (int_done_map) {
+        modified = priv->int_done_map | priv->atl_done_map;
+
+        while (priv->int_done_map || priv->atl_done_map) {
+                if (priv->int_done_map) {
                         /* INT ptd */
-                        slot = __ffs(int_done_map);
-                        int_done_map &= ~(1 << slot);
+                        slot = __ffs(priv->int_done_map);
+                        priv->int_done_map &= ~(1 << slot);
                         slots = priv->int_slots;
-                        if (!slots[slot].qh)
+                        /* This should not trigger, and could be removed if
+                           noone have any problems with it triggering: */
+                        if (!slots[slot].qh) {
+                                WARN_ON(1);
                                 continue;
+                        }
                         ptd_offset = INT_PTD_OFFSET;
                         ptd_read(hcd->regs, INT_PTD_OFFSET, slot, &ptd);
                         state = check_int_transfer(hcd, &ptd,
                                                         slots[slot].qtd->urb);
                 } else {
                         /* ATL ptd */
-                        slot = __ffs(atl_done_map);
-                        atl_done_map &= ~(1 << slot);
+                        slot = __ffs(priv->atl_done_map);
+                        priv->atl_done_map &= ~(1 << slot);
                         slots = priv->atl_slots;
-                        if (!slots[slot].qh)
+                        /* This should not trigger, and could be removed if
+                           noone have any problems with it triggering: */
+                        if (!slots[slot].qh) {
+                                WARN_ON(1);
                                 continue;
+                        }
                         ptd_offset = ATL_PTD_OFFSET;
                         ptd_read(hcd->regs, ATL_PTD_OFFSET, slot, &ptd);
                         state = check_atl_transfer(hcd, &ptd,
@@ -1509,14 +1545,41 @@ out:
         return retval;
 }
 
+static void kill_transfer(struct usb_hcd *hcd, struct urb *urb,
+                struct isp1760_qh *qh)
+{
+        struct isp1760_hcd *priv = hcd_to_priv(hcd);
+        int skip_map;
+
+        WARN_ON(qh->slot == -1);
+
+        /* We need to forcefully reclaim the slot since some transfers never
+           return, e.g. interrupt transfers and NAKed bulk transfers. */
+        if (usb_pipebulk(urb->pipe)) {
+                skip_map = reg_read32(hcd->regs, HC_ATL_PTD_SKIPMAP_REG);
+                skip_map |= (1 << qh->slot);
+                reg_write32(hcd->regs, HC_ATL_PTD_SKIPMAP_REG, skip_map);
+                priv->atl_slots[qh->slot].qh = NULL;
+                priv->atl_slots[qh->slot].qtd = NULL;
+        } else {
+                skip_map = reg_read32(hcd->regs, HC_INT_PTD_SKIPMAP_REG);
+                skip_map |= (1 << qh->slot);
+                reg_write32(hcd->regs, HC_INT_PTD_SKIPMAP_REG, skip_map);
+                priv->int_slots[qh->slot].qh = NULL;
+                priv->int_slots[qh->slot].qtd = NULL;
+        }
+
+        qh->slot = -1;
+        priv->active_ptds--;
+}
+
 static int isp1760_urb_dequeue(struct usb_hcd *hcd, struct urb *urb,
                 int status)
 {
         struct isp1760_hcd *priv = hcd_to_priv(hcd);
+        unsigned long spinflags;
         struct isp1760_qh *qh;
         struct isp1760_qtd *qtd;
-        struct ptd ptd;
-        unsigned long spinflags;
         int retval = 0;
 
         spin_lock_irqsave(&priv->lock, spinflags);
@@ -1527,34 +1590,18 @@ static int isp1760_urb_dequeue(struct usb_hcd *hcd, struct urb *urb,
                 goto out;
         }
 
-        /* We need to forcefully reclaim the slot since some transfers never
-           return, e.g. interrupt transfers and NAKed bulk transfers. */
-        if (qh->slot > -1) {
-                memset(&ptd, 0, sizeof(ptd));
-                if (usb_pipebulk(urb->pipe)) {
-                        priv->atl_slots[qh->slot].qh = NULL;
-                        priv->atl_slots[qh->slot].qtd = NULL;
-                        ptd_write(hcd->regs, ATL_PTD_OFFSET, qh->slot, &ptd);
-                } else {
-                        priv->int_slots[qh->slot].qh = NULL;
-                        priv->int_slots[qh->slot].qtd = NULL;
-                        ptd_write(hcd->regs, INT_PTD_OFFSET, qh->slot, &ptd);
-                }
-                priv->active_ptds--;
-                qh->slot = -1;
-        }
-
-        list_for_each_entry(qtd, &qh->qtd_list, qtd_list) {
-                if (qtd->urb == urb)
+        list_for_each_entry(qtd, &qh->qtd_list, qtd_list)
+                if (qtd->urb == urb) {
+                        if (qtd->status == QTD_XFER_STARTED)
+                                kill_transfer(hcd, urb, qh);
                         qtd->status = QTD_RETIRE;
-        }
+                }
 
         urb->status = status;
         schedule_ptds(hcd);
 
 out:
         spin_unlock_irqrestore(&priv->lock, spinflags);
-
         return retval;
 }
 
@@ -1562,32 +1609,28 @@ static void isp1760_endpoint_disable(struct usb_hcd *hcd,
                 struct usb_host_endpoint *ep)
 {
         struct isp1760_hcd *priv = hcd_to_priv(hcd);
+        unsigned long spinflags;
         struct isp1760_qh *qh;
         struct isp1760_qtd *qtd;
-        unsigned long spinflags;
-        int do_iter;
 
         spin_lock_irqsave(&priv->lock, spinflags);
+
         qh = ep->hcpriv;
         if (!qh)
                 goto out;
 
-        do_iter = !list_empty(&qh->qtd_list);
-        while (do_iter) {
-                do_iter = 0;
-                list_for_each_entry(qtd, &qh->qtd_list, qtd_list) {
-                        if (qtd->urb->ep == ep) {
-                                spin_unlock_irqrestore(&priv->lock, spinflags);
-                                isp1760_urb_dequeue(hcd, qtd->urb, -ECONNRESET);
-                                spin_lock_irqsave(&priv->lock, spinflags);
-                                do_iter = 1;
-                                break; /* Restart iteration */
-                        }
-                }
+        list_for_each_entry(qtd, &qh->qtd_list, qtd_list) {
+                if (qtd->status == QTD_XFER_STARTED)
+                        kill_transfer(hcd, qtd->urb, qh);
+                qtd->status = QTD_RETIRE;
+                qtd->urb->status = -ECONNRESET;
         }
+
         ep->hcpriv = NULL;
         /* Cannot free qh here since it will be parsed by schedule_ptds() */
 
+        schedule_ptds(hcd);
+
 out:
         spin_unlock_irqrestore(&priv->lock, spinflags);
 }