patch-2.4.21 linux-2.4.21/drivers/usb/auerbuf.c

• Lines: 151
• Date: 2003-06-13 07:51:36.000000000 -0700
• Orig file: linux-2.4.20/drivers/usb/auerbuf.c
• Orig date: 1969-12-31 16:00:00.000000000 -0800

diff -urN linux-2.4.20/drivers/usb/auerbuf.c linux-2.4.21/drivers/usb/auerbuf.c
@@ -0,0 +1,150 @@
+/*****************************************************************************/
+/*
+ *      auerbuf.c  --  Auerswald PBX/System Telephone urb list storage.
+ *
+ *      Copyright (C) 2002  Wolfgang Mües (wolfgang@iksw-muees.de)
+ *
+ *      This program is free software; you can redistribute it and/or modify
+ *      it under the terms of the GNU General Public License as published by
+ *      the Free Software Foundation; either version 2 of the License, or
+ *      (at your option) any later version.
+ *
+ *      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, write to the Free Software
+ *      Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
+ */
+ /*****************************************************************************/
+
+#undef DEBUG			/* include debug macros until it's done */
+#include <linux/usb.h>
+#include "auerbuf.h"
+#include <linux/slab.h>
+
+/* free a single auerbuf */
+void auerbuf_free(struct auerbuf *bp)
+{
+	if (!bp) return;
+	kfree(bp->bufp);
+	kfree(bp->dr);
+	if (bp->urbp) {
+		usb_free_urb(bp->urbp);
+	}
+	kfree(bp);
+}
+
+/* free the buffers from an auerbuf list */
+void auerbuf_free_list(struct list_head *q)
+{
+	struct list_head *tmp;
+	struct list_head *p;
+	struct auerbuf *bp;
+
+	dbg("auerbuf_free_list");
+	for (p = q->next; p != q;) {
+		bp = list_entry(p, struct auerbuf, buff_list);
+		tmp = p->next;
+		list_del(p);
+		p = tmp;
+		auerbuf_free(bp);
+	}
+}
+
+/* free all buffers from an auerbuf chain */
+void auerbuf_free_buffers(struct auerbufctl *bcp)
+{
+	unsigned long flags;
+	dbg("auerbuf_free_buffers");
+
+	spin_lock_irqsave(&bcp->lock, flags);
+
+	auerbuf_free_list(&bcp->free_buff_list);
+	auerbuf_free_list(&bcp->rec_buff_list);
+
+	spin_unlock_irqrestore(&bcp->lock, flags);
+}
+
+/* init the members of a list control block */
+void auerbuf_init(struct auerbufctl *bcp)
+{
+	dbg("auerbuf_init");
+	spin_lock_init(&bcp->lock);
+	INIT_LIST_HEAD(&bcp->free_buff_list);
+	INIT_LIST_HEAD(&bcp->rec_buff_list);
+}
+
+/* setup a list of buffers */
+/* requirement: auerbuf_init() */
+int auerbuf_setup(struct auerbufctl *bcp, unsigned int numElements,
+		  unsigned int bufsize)
+{
+	struct auerbuf *bep = NULL;
+
+	dbg("auerbuf_setup called with %d elements of %d bytes",
+	    numElements, bufsize);
+
+	/* fill the list of free elements */
+	for (; numElements; numElements--) {
+		bep =
+		    (struct auerbuf *) kmalloc(sizeof(struct auerbuf),
+					       GFP_KERNEL);
+		if (!bep)
+			goto bl_fail;
+		memset(bep, 0, sizeof(struct auerbuf));
+		bep->list = bcp;
+		INIT_LIST_HEAD(&bep->buff_list);
+		bep->bufp = (char *) kmalloc(bufsize, GFP_KERNEL);
+		if (!bep->bufp)
+			goto bl_fail;
+		bep->dr =
+		    (struct usb_ctrlrequest *)
+		    kmalloc(sizeof(struct usb_ctrlrequest), GFP_KERNEL);
+		if (!bep->dr)
+			goto bl_fail;
+		bep->urbp = usb_alloc_urb(0);
+		if (!bep->urbp)
+			goto bl_fail;
+		list_add_tail(&bep->buff_list, &bcp->free_buff_list);
+	}
+	return 0;
+
+      bl_fail:			/* not enought memory. Free allocated elements */
+	dbg("auerbuf_setup: no more memory");
+	auerbuf_free (bep);
+	auerbuf_free_buffers(bcp);
+	return -ENOMEM;
+}
+
+/* alloc a free buffer from the list. Returns NULL if no buffer available */
+struct auerbuf *auerbuf_getbuf(struct auerbufctl *bcp)
+{
+	unsigned long flags;
+	struct auerbuf *bp = NULL;
+
+	spin_lock_irqsave(&bcp->lock, flags);
+	if (!list_empty(&bcp->free_buff_list)) {
+		/* yes: get the entry */
+		struct list_head *tmp = bcp->free_buff_list.next;
+		list_del(tmp);
+		bp = list_entry(tmp, struct auerbuf, buff_list);
+	}
+	spin_unlock_irqrestore(&bcp->lock, flags);
+	return bp;
+}
+
+/* insert a used buffer into the free list */
+void auerbuf_releasebuf(struct auerbuf *bp)
+{
+	unsigned long flags;
+	struct auerbufctl *bcp = bp->list;
+	bp->retries = 0;
+
+	dbg("auerbuf_releasebuf called");
+	spin_lock_irqsave(&bcp->lock, flags);
+	list_add_tail(&bp->buff_list, &bcp->free_buff_list);
+	spin_unlock_irqrestore(&bcp->lock, flags);
+}