[src/nick-nhusb]: src/sys/dev/usb Do the same loan dance with control transfe...

[skrll <skrll%NetBSD.org@localhost>]

details:   https://anonhg.NetBSD.org/src/rev/71917f1772a5
branches:  nick-nhusb
changeset: 334370:71917f1772a5
user:      skrll <skrll%NetBSD.org@localhost>
date:      Sun Jan 10 10:16:00 2016 +0000

description:
Do the same loan dance with control transfers as with other transfer
types.  That is,

        Use the pipe "tail" TD as our first and loan our first TD to the
        next transfer.

Sprinkle the above comment where necessary.

Also, remove a TD from the hash list BEFORE calling into
usb_transfer_complete.  It might get reused when starting the next
transfer.

diffstat:

 sys/dev/usb/ohci.c    |  55 +++++++++++++++++++++++++++++++-------------------
 sys/dev/usb/ohcivar.h |  15 +++----------
 2 files changed, 38 insertions(+), 32 deletions(-)

diffs (179 lines):

diff -r 3b645852ad83 -r 71917f1772a5 sys/dev/usb/ohci.c
--- a/sys/dev/usb/ohci.c        Sat Jan 09 21:47:23 2016 +0000
+++ b/sys/dev/usb/ohci.c        Sun Jan 10 10:16:00 2016 +0000
@@ -1,4 +1,4 @@
-/*     $NetBSD: ohci.c,v 1.254.2.41 2016/01/09 21:45:20 skrll Exp $    */
+/*     $NetBSD: ohci.c,v 1.254.2.42 2016/01/10 10:16:00 skrll Exp $    */
 
 /*
  * Copyright (c) 1998, 2004, 2005, 2012 The NetBSD Foundation, Inc.
@@ -41,7 +41,7 @@
  */
 
 #include <sys/cdefs.h>
-__KERNEL_RCSID(0, "$NetBSD: ohci.c,v 1.254.2.41 2016/01/09 21:45:20 skrll Exp $");
+__KERNEL_RCSID(0, "$NetBSD: ohci.c,v 1.254.2.42 2016/01/10 10:16:00 skrll Exp $");
 
 #include "opt_usb.h"
 
@@ -1527,11 +1527,11 @@
 
                cc = OHCI_TD_GET_CC(O32TOH(std->td.td_flags));
                if (cc == OHCI_CC_NO_ERROR) {
+                       ohci_hash_rem_td(sc, std);
                        if (std->flags & OHCI_CALL_DONE) {
                                xfer->ux_status = USBD_NORMAL_COMPLETION;
                                usb_transfer_complete(xfer);
                        }
-                       ohci_hash_rem_td(sc, std);
                } else {
                        /*
                         * Endpoint is halted.  First unlink all the TDs
@@ -1686,7 +1686,10 @@
                ohci_soft_td_t *data, *last, *tail;
                int len = xfer->ux_length;
 
-               /* Use "tail" TD and loan our first TD to next transfer */
+               /*
+                * Use the pipe "tail" TD as our first and loan our first TD
+                * to the next transfer.
+                */
                data = opipe->tail.td;
                opipe->tail.td = ox->ox_stds[0];
                ox->ox_stds[0] = data;
@@ -2728,26 +2731,24 @@
        struct ohci_xfer *ox = OHCI_XFER2OXFER(xfer);
        usb_device_request_t *req = &xfer->ux_request;
        ohci_softc_t *sc = OHCI_XFER2SC(xfer);
-       ohci_soft_td_t *stat, *tail;
+       ohci_soft_td_t *stat, *setup;
        int isread = req->bmRequestType & UT_READ;
        int len = xfer->ux_bufsize;
        int err = ENOMEM;
 
        OHCIHIST_FUNC(); OHCIHIST_CALLED();
 
-       /* The TD for setup will be a 'tail' from elsewhere */
-       stat = ohci_alloc_std(sc);
-       if (stat == NULL) {
+       setup = ohci_alloc_std(sc);
+       if (setup == NULL) {
                goto bad1;
        }
-       tail = ohci_alloc_std(sc);
-       if (tail == NULL) {
+       stat = ohci_alloc_std(sc);
+       if (stat == NULL) {
                goto bad2;
        }
-       tail->xfer = NULL;
-
+
+       ox->ox_setup = setup;
        ox->ox_stat = stat;
-       ox->ox_tdtail = tail;
        ox->ox_nstd = 0;
 
        /* Set up data transaction */
@@ -2760,9 +2761,9 @@
        return 0;
 
  bad3:
-       ohci_free_std(sc, tail);
+       ohci_free_std(sc, stat);
  bad2:
-       ohci_free_std(sc, stat);
+       ohci_free_std(sc, setup);
  bad1:
        return err;
 }
@@ -2778,8 +2779,8 @@
        DPRINTFN(8, "xfer %p nstd %d", xfer, ox->ox_nstd, 0, 0);
 
        mutex_enter(&sc->sc_lock);
-       if (ox->ox_tdtail != opipe->tail.td) {
-               ohci_free_std_locked(sc, ox->ox_tdtail);
+       if (ox->ox_setup != opipe->tail.td) {
+               ohci_free_std_locked(sc, ox->ox_setup);
        }
        for (size_t i = 0; i < ox->ox_nstd; i++) {
                ohci_soft_td_t *std = ox->ox_stds[i];
@@ -2845,10 +2846,16 @@
        /* Need to take lock here for pipe->tail.td */
        mutex_enter(&sc->sc_lock);
 
+       /*
+        * Use the pipe "tail" TD as our first and loan our first TD to the
+        * next transfer
+        */
        setup = opipe->tail.td;
+       opipe->tail.td = ox->ox_setup;
+       ox->ox_setup = setup;
+
        stat = ox->ox_stat;
-       tail = ox->ox_tdtail;
-       opipe->tail.td = tail;
+       tail = opipe->tail.td;  /* point at sentinel */
 
        sed = opipe->sed;
 
@@ -3125,7 +3132,10 @@
 
        mutex_enter(&sc->sc_lock);
 
-       /* Use "tail" TD and loan our first TD to next transfer */
+       /*
+        * Use the pipe "tail" TD as our first and loan our first TD to the
+        * next transfer
+        */
        data = opipe->tail.td;
        opipe->tail.td = ox->ox_stds[0];
        ox->ox_stds[0] = data;
@@ -3319,7 +3329,10 @@
 
        mutex_enter(&sc->sc_lock);
 
-       /* Use "tail" TD and loan our first TD to next transfer */
+       /*
+        * Use the pipe "tail" TD as our first and loan our first TD to the
+        * next transfer.
+        */
        data = opipe->tail.td;
        opipe->tail.td = ox->ox_stds[0];
        ox->ox_stds[0] = data;
diff -r 3b645852ad83 -r 71917f1772a5 sys/dev/usb/ohcivar.h
--- a/sys/dev/usb/ohcivar.h     Sat Jan 09 21:47:23 2016 +0000
+++ b/sys/dev/usb/ohcivar.h     Sun Jan 10 10:16:00 2016 +0000
@@ -1,4 +1,4 @@
-/*     $NetBSD: ohcivar.h,v 1.55.6.11 2015/12/06 15:39:35 skrll Exp $  */
+/*     $NetBSD: ohcivar.h,v 1.55.6.12 2016/01/10 10:16:00 skrll Exp $  */
 
 /*
  * Copyright (c) 1998 The NetBSD Foundation, Inc.
@@ -146,14 +146,9 @@
 struct ohci_xfer {
        struct usbd_xfer xfer;
        struct usb_task abort_task;
-       /*
-        * The TD/iTD that is used to terminate the chain and is borrowed
-        * by the next transfer for its first TD
-        */
-       union {
-               ohci_soft_td_t *ox_tdtail;
-               ohci_soft_itd_t *ox_itdtail;
-       };
+       /* ctrl */
+       ohci_soft_td_t *ox_setup;
+       ohci_soft_td_t *ox_stat;
        union {
                /* ctrl/bulk/intr */
                struct {
@@ -166,8 +161,6 @@
                        size_t ox_nsitd;
                };
        };
-       /* ctrl */
-       ohci_soft_td_t *ox_stat;
 };
 
 #define OHCI_BUS2SC(bus)       ((bus)->ub_hcpriv)