[PATCH] sh: DMA updates

This extends the current SH DMA API somewhat to support a proper virtual
channel abstraction, and also works to represent this through the driver model
by giving each DMAC its own platform device.

There's also a few other minor changes to support a few new CPU subtypes, and
make TEI generation for the SH DMAC configurable.

Signed-off-by: Paul Mundt <lethal@linux-sh.org>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>

arch/sh/drivers/dma/dma-api.c

@@ -3,7 +3,7 @@
  *
  * SuperH-specific DMA management API
  *
- * Copyright (C) 2003, 2004  Paul Mundt
+ * Copyright (C) 2003, 2004, 2005  Paul Mundt
  *
  * This file is subject to the terms and conditions of the GNU General Public
  * License.  See the file "COPYING" in the main directory of this archive
@@ -15,6 +15,7 @@
 #include <linux/spinlock.h>
 #include <linux/proc_fs.h>
 #include <linux/list.h>
+#include <linux/platform_device.h>
 #include <asm/dma.h>
 
 DEFINE_SPINLOCK(dma_spin_lock);
@@ -55,16 +56,14 @@ static LIST_HEAD(registered_dmac_list);
 
 struct dma_info *get_dma_info(unsigned int chan)
 {
-	struct list_head *pos, *tmp;
+	struct dma_info *info;
 	unsigned int total = 0;
 
 	/*
 	 * Look for each DMAC's range to determine who the owner of
 	 * the channel is.
 	 */
-	list_for_each_safe(pos, tmp, &registered_dmac_list) {
-		struct dma_info *info = list_entry(pos, struct dma_info, list);
-
+	list_for_each_entry(info, &registered_dmac_list, list) {
 		total += info->nr_channels;
 		if (chan > total)
 			continue;
@@ -75,6 +74,20 @@ struct dma_info *get_dma_info(unsigned int chan)
 	return NULL;
 }
 
+static unsigned int get_nr_channels(void)
+{
+	struct dma_info *info;
+	unsigned int nr = 0;
+
+	if (unlikely(list_empty(&registered_dmac_list)))
+		return nr;
+
+	list_for_each_entry(info, &registered_dmac_list, list)
+		nr += info->nr_channels;
+
+	return nr;
+}
+
 struct dma_channel *get_dma_channel(unsigned int chan)
 {
 	struct dma_info *info = get_dma_info(chan);
@@ -173,7 +186,7 @@ int dma_xfer(unsigned int chan, unsigned long from,
 static int dma_read_proc(char *buf, char **start, off_t off,
 			 int len, int *eof, void *data)
 {
-	struct list_head *pos, *tmp;
+	struct dma_info *info;
 	char *p = buf;
 
 	if (list_empty(&registered_dmac_list))
@@ -182,8 +195,7 @@ static int dma_read_proc(char *buf, char **start, off_t off,
 	/*
 	 * Iterate over each registered DMAC
 	 */
-	list_for_each_safe(pos, tmp, &registered_dmac_list) {
-		struct dma_info *info = list_entry(pos, struct dma_info, list);
+	list_for_each_entry(info, &registered_dmac_list, list) {
 		int i;
 
 		/*
@@ -205,9 +217,9 @@ static int dma_read_proc(char *buf, char **start, off_t off,
 #endif
 
 
-int __init register_dmac(struct dma_info *info)
+int register_dmac(struct dma_info *info)
 {
-	int i;
+	unsigned int total_channels, i;
 
 	INIT_LIST_HEAD(&info->list);
 
@@ -217,6 +229,11 @@ int __init register_dmac(struct dma_info *info)
 
 	BUG_ON((info->flags & DMAC_CHANNELS_CONFIGURED) && !info->channels);
 
+	info->pdev = platform_device_register_simple((char *)info->name, -1,
+						     NULL, 0);
+	if (IS_ERR(info->pdev))
+		return PTR_ERR(info->pdev);
+
 	/*
 	 * Don't touch pre-configured channels
 	 */
@@ -232,10 +249,12 @@ int __init register_dmac(struct dma_info *info)
 		memset(info->channels, 0, size);
 	}
 
+	total_channels = get_nr_channels();
 	for (i = 0; i < info->nr_channels; i++) {
 		struct dma_channel *chan = info->channels + i;
 
 		chan->chan = i;
+		chan->vchan = i + total_channels;
 
 		memcpy(chan->dev_id, "Unused", 7);
 
@@ -245,22 +264,26 @@ int __init register_dmac(struct dma_info *info)
 		init_MUTEX(&chan->sem);
 		init_waitqueue_head(&chan->wait_queue);
 
-#ifdef CONFIG_SYSFS
-		dma_create_sysfs_files(chan);
-#endif
+		dma_create_sysfs_files(chan, info);
 	}
 
 	list_add(&info->list, &registered_dmac_list);
 
 	return 0;
 }
 
-void __exit unregister_dmac(struct dma_info *info)
+void unregister_dmac(struct dma_info *info)
 {
+	unsigned int i;
+
+	for (i = 0; i < info->nr_channels; i++)
+		dma_remove_sysfs_files(info->channels + i, info);
+
 	if (!(info->flags & DMAC_CHANNELS_CONFIGURED))
 		kfree(info->channels);
 
 	list_del(&info->list);
+	platform_device_unregister(info->pdev);
 }
 
 static int __init dma_api_init(void)

arch/sh/drivers/dma/dma-g2.c

@@ -140,7 +140,7 @@ static struct dma_ops g2_dma_ops = {
 };
 
 static struct dma_info g2_dma_info = {
-	.name		= "G2 DMA",
+	.name		= "g2_dmac",
 	.nr_channels	= 4,
 	.ops		= &g2_dma_ops,
 	.flags		= DMAC_CHANNELS_TEI_CAPABLE,
@@ -160,6 +160,7 @@ static int __init g2_dma_init(void)
 static void __exit g2_dma_exit(void)
 {
 	free_irq(HW_EVENT_G2_DMA, 0);
+	unregister_dmac(&g2_dma_info);
 }
 
 subsys_initcall(g2_dma_init);

arch/sh/drivers/dma/dma-isa.c

@@ -25,14 +25,14 @@
  * such, this code is meant for only the simplest of tasks (and shouldn't be
  * used in any new drivers at all).
  *
- * It should also be noted that various functions here are labelled as
- * being deprecated. This is due to the fact that the ops->xfer() method is
- * the preferred way of doing things (as well as just grabbing the spinlock
- * directly). As such, any users of this interface will be warned rather
- * loudly.
+ * NOTE: ops->xfer() is the preferred way of doing things. However, there
+ * are some users of the ISA DMA API that exist in common code that we
+ * don't necessarily want to go out of our way to break, so we still
+ * allow for some compatability at that level. Any new code is strongly
+ * advised to run far away from the ISA DMA API and use the SH DMA API
+ * directly.
  */
-
-unsigned long __deprecated claim_dma_lock(void)
+unsigned long claim_dma_lock(void)
 {
 	unsigned long flags;
 
@@ -42,19 +42,19 @@ unsigned long __deprecated claim_dma_lock(void)
 }
 EXPORT_SYMBOL(claim_dma_lock);
 
-void __deprecated release_dma_lock(unsigned long flags)
+void release_dma_lock(unsigned long flags)
 {
 	spin_unlock_irqrestore(&dma_spin_lock, flags);
 }
 EXPORT_SYMBOL(release_dma_lock);
 
-void __deprecated disable_dma(unsigned int chan)
+void disable_dma(unsigned int chan)
 {
 	/* Nothing */
 }
 EXPORT_SYMBOL(disable_dma);
 
-void __deprecated enable_dma(unsigned int chan)
+void enable_dma(unsigned int chan)
 {
 	struct dma_info *info = get_dma_info(chan);
 	struct dma_channel *channel = &info->channels[chan];

arch/sh/drivers/dma/dma-pvr2.c

@@ -80,7 +80,7 @@ static struct dma_ops pvr2_dma_ops = {
 };
 
 static struct dma_info pvr2_dma_info = {
-	.name		= "PowerVR 2 DMA",
+	.name		= "pvr2_dmac",
 	.nr_channels	= 1,
 	.ops		= &pvr2_dma_ops,
 	.flags		= DMAC_CHANNELS_TEI_CAPABLE,
@@ -98,6 +98,7 @@ static void __exit pvr2_dma_exit(void)
 {
 	free_dma(PVR2_CASCADE_CHAN);
 	free_irq(HW_EVENT_PVR2_DMA, 0);
+	unregister_dmac(&pvr2_dma_info);
 }
 
 subsys_initcall(pvr2_dma_init);