[PATCH] sh: DMA driver updates.

From: Paul Mundt <lethal@Linux-SH.ORG>

This updates the SuperH DMA driver, as well as cleaning up the registration
interface.

We also drop the use of bitfields in dma-sh since things like the SH4-202,
7751R, 7760, etc.  all have a completely different set of register
definitions.
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/Makefile

@@ -3,6 +3,7 @@
 #
 
 obj-y				+= dma-api.o dma-isa.o
+obj-$(CONFIG_SYSFS)		+= dma-sysfs.o
 obj-$(CONFIG_SH_DMA)		+= dma-sh.o
 obj-$(CONFIG_SH_DREAMCAST)	+= dma-pvr2.o dma-g2.o
 

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

@@ -3,7 +3,7 @@
  *
  * SuperH-specific DMA management API
  *
- * Copyright (C) 2003  Paul Mundt
+ * Copyright (C) 2003, 2004  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
@@ -14,10 +14,11 @@
 #include <linux/interrupt.h>
 #include <linux/spinlock.h>
 #include <linux/proc_fs.h>
+#include <linux/list.h>
 #include <asm/dma.h>
 
-struct dma_info dma_info[MAX_DMA_CHANNELS] = { { 0, } };
 spinlock_t dma_spin_lock = SPIN_LOCK_UNLOCKED;
+static LIST_HEAD(registered_dmac_list);
 
 /*
  * A brief note about the reasons for this API as it stands.
@@ -54,15 +55,43 @@ spinlock_t dma_spin_lock = SPIN_LOCK_UNLOCKED;
 
 struct dma_info *get_dma_info(unsigned int chan)
 {
-	return dma_info + chan;
+	struct list_head *pos, *tmp;
+	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);
+
+		total += info->nr_channels;
+		if (chan > total)
+			continue;
+
+		return info;
+	}
+
+	return NULL;
+}
+
+struct dma_channel *get_dma_channel(unsigned int chan)
+{
+	struct dma_info *info = get_dma_info(chan);
+
+	if (!info)
+		return ERR_PTR(-EINVAL);
+
+	return info->channels + chan;
 }
 
 int get_dma_residue(unsigned int chan)
 {
 	struct dma_info *info = get_dma_info(chan);
+	struct dma_channel *channel = &info->channels[chan];
 
 	if (info->ops->get_residue)
-		return info->ops->get_residue(info);
+		return info->ops->get_residue(channel);
 
 	return 0;
 }
@@ -70,22 +99,23 @@ int get_dma_residue(unsigned int chan)
 int request_dma(unsigned int chan, const char *dev_id)
 {
 	struct dma_info *info = get_dma_info(chan);
+	struct dma_channel *channel = &info->channels[chan];
 
-	down(&info->sem);
+	down(&channel->sem);
 
 	if (!info->ops || chan >= MAX_DMA_CHANNELS) {
-		up(&info->sem);
+		up(&channel->sem);
 		return -EINVAL;
 	}
 
-	atomic_set(&info->busy, 1);
+	atomic_set(&channel->busy, 1);
 
-	info->dev_id = dev_id;
+	strlcpy(channel->dev_id, dev_id, sizeof(channel->dev_id));
 
-	up(&info->sem);
+	up(&channel->sem);
 
 	if (info->ops->request)
-		return info->ops->request(info);
+		return info->ops->request(channel);
 
 	return 0;
 }
@@ -93,85 +123,145 @@ int request_dma(unsigned int chan, const char *dev_id)
 void free_dma(unsigned int chan)
 {
 	struct dma_info *info = get_dma_info(chan);
+	struct dma_channel *channel = &info->channels[chan];
 
 	if (info->ops->free)
-		info->ops->free(info);
+		info->ops->free(channel);
 
-	atomic_set(&info->busy, 0);
+	atomic_set(&channel->busy, 0);
 }
 
 void dma_wait_for_completion(unsigned int chan)
 {
 	struct dma_info *info = get_dma_info(chan);
+	struct dma_channel *channel = &info->channels[chan];
 
-	if (info->tei_capable) {
-		wait_event(info->wait_queue, (info->ops->get_residue(info) == 0));
+	if (channel->flags & DMA_TEI_CAPABLE) {
+		wait_event(channel->wait_queue,
+			   (info->ops->get_residue(channel) == 0));
 		return;
 	}
 
-	while (info->ops->get_residue(info))
+	while (info->ops->get_residue(channel))
 		cpu_relax();
 }
 
 void dma_configure_channel(unsigned int chan, unsigned long flags)
 {
 	struct dma_info *info = get_dma_info(chan);
+	struct dma_channel *channel = &info->channels[chan];
 
 	if (info->ops->configure)
-		info->ops->configure(info, flags);
+		info->ops->configure(channel, flags);
 }
 
 int dma_xfer(unsigned int chan, unsigned long from,
 	     unsigned long to, size_t size, unsigned int mode)
 {
 	struct dma_info *info = get_dma_info(chan);
+	struct dma_channel *channel = &info->channels[chan];
 
-	info->sar	= from;
-	info->dar	= to;
-	info->count	= size;
-	info->mode	= mode;
+	channel->sar	= from;
+	channel->dar	= to;
+	channel->count	= size;
+	channel->mode	= mode;
 
-	return info->ops->xfer(info);
+	return info->ops->xfer(channel);
 }
 
 #ifdef CONFIG_PROC_FS
 static int dma_read_proc(char *buf, char **start, off_t off,
 			 int len, int *eof, void *data)
 {
-	struct dma_info *info;
+	struct list_head *pos, *tmp;
 	char *p = buf;
+
+	if (list_empty(&registered_dmac_list))
+		return 0;
+
+	/*
+	 * 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);
 		int i;
 
-	for (i = 0, info = dma_info; i < MAX_DMA_CHANNELS; i++, info++) {
-		if (!atomic_read(&info->busy))
+		/*
+		 * Iterate over each channel
+		 */
+		for (i = 0; i < info->nr_channels; i++) {
+			struct dma_channel *channel = info->channels + i;
+
+			if (!(channel->flags & DMA_CONFIGURED))
 				continue;
 
 			p += sprintf(p, "%2d: %14s    %s\n", i,
-			     info->ops->name, info->dev_id);
+				     info->name, channel->dev_id);
+		}
 	}
 
 	return p - buf;
 }
 #endif
 
-int __init register_dmac(struct dma_ops *ops)
+
+int __init register_dmac(struct dma_info *info)
 {
 	int i;
 
-	printk("DMA: Registering %s handler.\n", ops->name);
+	INIT_LIST_HEAD(&info->list);
+
+	printk(KERN_INFO "DMA: Registering %s handler (%d channels).\n",
+	       info->name, info->nr_channels);
+
+	BUG_ON((info->flags & DMAC_CHANNELS_CONFIGURED) && !info->channels);
+
+	/*
+	 * Don't touch pre-configured channels
+	 */
+	if (!(info->flags & DMAC_CHANNELS_CONFIGURED)) {
+		unsigned int size;
 
-	for (i = 0; i < MAX_DMA_CHANNELS; i++) {
-		struct dma_info *info = get_dma_info(i);
+		size = sizeof(struct dma_channel) * info->nr_channels;
 
-		info->chan = i;
+		info->channels = kmalloc(size, GFP_KERNEL);
+		if (!info->channels)
+			return -ENOMEM;
 
-		init_MUTEX(&info->sem);
-		init_waitqueue_head(&info->wait_queue);
+		memset(info->channels, 0, size);
 	}
 
+	for (i = 0; i < info->nr_channels; i++) {
+		struct dma_channel *chan = info->channels + i;
+
+		chan->chan = i;
+
+		memcpy(chan->dev_id, "Unused", 7);
+
+		if (info->flags & DMAC_CHANNELS_TEI_CAPABLE)
+			chan->flags |= DMA_TEI_CAPABLE;
+
+		init_MUTEX(&chan->sem);
+		init_waitqueue_head(&chan->wait_queue);
+
+#ifdef CONFIG_SYSFS
+		dma_create_sysfs_files(chan);
+#endif
+	}
+
+	list_add(&info->list, &registered_dmac_list);
+
 	return 0;
 }
 
+void __exit unregister_dmac(struct dma_info *info)
+{
+	if (!(info->flags & DMAC_CHANNELS_CONFIGURED))
+		kfree(info->channels);
+
+	list_del(&info->list);
+}
+
 static int __init dma_api_init(void)
 {
 	printk("DMA: Registering DMA API.\n");
@@ -191,8 +281,11 @@ MODULE_LICENSE("GPL");
 
 EXPORT_SYMBOL(request_dma);
 EXPORT_SYMBOL(free_dma);
+EXPORT_SYMBOL(register_dmac);
+EXPORT_SYMBOL(unregister_dmac);
 EXPORT_SYMBOL(get_dma_residue);
 EXPORT_SYMBOL(get_dma_info);
+EXPORT_SYMBOL(get_dma_channel);
 EXPORT_SYMBOL(dma_xfer);
 EXPORT_SYMBOL(dma_wait_for_completion);
 EXPORT_SYMBOL(dma_configure_channel);

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

@@ -3,13 +3,14 @@
  *
  * Generic ISA DMA wrapper for SH DMA API
  *
- * Copyright (C) 2003  Paul Mundt
+ * Copyright (C) 2003, 2004  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
  * for more details.
  */
 #include <linux/kernel.h>
+#include <linux/module.h>
 #include <asm/dma.h>
 
 /*
@@ -39,55 +40,67 @@ unsigned long __deprecated claim_dma_lock(void)
 
 	return flags;
 }
+EXPORT_SYMBOL(claim_dma_lock);
 
 void __deprecated 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)
 {
 	/* Nothing */
 }
+EXPORT_SYMBOL(disable_dma);
 
 void __deprecated enable_dma(unsigned int chan)
 {
 	struct dma_info *info = get_dma_info(chan);
+	struct dma_channel *channel = &info->channels[chan];
 
-	info->ops->xfer(info);
+	info->ops->xfer(channel);
 }
+EXPORT_SYMBOL(enable_dma);
 
 void clear_dma_ff(unsigned int chan)
 {
 	/* Nothing */
 }
+EXPORT_SYMBOL(clear_dma_ff);
 
 void set_dma_mode(unsigned int chan, char mode)
 {
 	struct dma_info *info = get_dma_info(chan);
+	struct dma_channel *channel = &info->channels[chan];
 
-	info->mode = mode;
+	channel->mode = mode;
 }
+EXPORT_SYMBOL(set_dma_mode);
 
 void set_dma_addr(unsigned int chan, unsigned int addr)
 {
 	struct dma_info *info = get_dma_info(chan);
+	struct dma_channel *channel = &info->channels[chan];
 
 	/*
 	 * Single address mode is the only thing supported through
 	 * this interface.
 	 */
-	if ((info->mode & DMA_MODE_MASK) == DMA_MODE_READ) {
-		info->sar = addr;
+	if ((channel->mode & DMA_MODE_MASK) == DMA_MODE_READ) {
+		channel->sar = addr;
 	} else {
-		info->dar = addr;
+		channel->dar = addr;
 	}
 }
+EXPORT_SYMBOL(set_dma_addr);
 
 void set_dma_count(unsigned int chan, unsigned int count)
 {
 	struct dma_info *info = get_dma_info(chan);
+	struct dma_channel *channel = &info->channels[chan];
 
-	info->count = count;
+	channel->count = count;
 }
+EXPORT_SYMBOL(set_dma_count);
 

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

 /*
- * arch/sh/kernel/cpu/dma.c
+ * arch/sh/drivers/dma/dma-sh.c
  *
- * Copyright (C) 2000 Takashi YOSHII
- * Copyright (C) 2003 Paul Mundt
+ * SuperH On-chip DMAC Support
  *
- * PC like DMA API for SuperH's DMAC.
+ * Copyright (C) 2000 Takashi YOSHII
+ * Copyright (C) 2003, 2004 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
@@ -29,38 +29,24 @@
  * Defaults to a 64-bit transfer size.
  */
 enum {
-	XMIT_SZ_64BIT	= 0,
-	XMIT_SZ_8BIT	= 1,
-	XMIT_SZ_16BIT	= 2,
-	XMIT_SZ_32BIT	= 3,
-	XMIT_SZ_256BIT	= 4,
+	XMIT_SZ_64BIT,
+	XMIT_SZ_8BIT,
+	XMIT_SZ_16BIT,
+	XMIT_SZ_32BIT,
+	XMIT_SZ_256BIT,
 };
 
 /*
  * The DMA count is defined as the number of bytes to transfer.
  */
 static unsigned int ts_shift[] = {
-	[XMIT_SZ_64BIT]		3,
-	[XMIT_SZ_8BIT]		0,
-	[XMIT_SZ_16BIT]		1,
-	[XMIT_SZ_32BIT]		2,
-	[XMIT_SZ_256BIT]	5,
-};
-
-struct sh_dmac_channel {
-        unsigned long sar;
-        unsigned long dar;
-        unsigned long dmatcr;
-        unsigned long chcr;
-} __attribute__ ((aligned(16)));
-
-struct sh_dmac_info {
-        struct sh_dmac_channel channel[4];
-        unsigned long dmaor;
+	[XMIT_SZ_64BIT]		= 3,
+	[XMIT_SZ_8BIT]		= 0,
+	[XMIT_SZ_16BIT]		= 1,
+	[XMIT_SZ_32BIT]		= 2,
+	[XMIT_SZ_256BIT]	= 5,
 };
 
-static volatile struct sh_dmac_info *sh_dmac = (volatile struct sh_dmac_info *)SH_DMAC_BASE;
-
 static inline unsigned int get_dmte_irq(unsigned int chan)
 {
 	unsigned int irq;
@@ -88,9 +74,13 @@ static inline unsigned int get_dmte_irq(unsigned int chan)
  *
  * iterations to complete the transfer.
  */
-static inline unsigned int calc_xmit_shift(struct dma_info *info)
+static inline unsigned int calc_xmit_shift(struct dma_channel *chan)
 {
-	return ts_shift[(sh_dmac->channel[info->chan].chcr >> 4) & 0x0007];
+	u32 chcr = ctrl_inl(CHCR[chan->chan]);
+
+	chcr >>= 4;
+
+	return ts_shift[chcr & 0x0007];
 }
 
 /*
@@ -101,66 +91,77 @@ static inline unsigned int calc_xmit_shift(struct dma_info *info)
  */
 static irqreturn_t dma_tei(int irq, void *dev_id, struct pt_regs *regs)
 {
-	struct dma_info * info = (struct dma_info *)dev_id;
-	u32 chcr = sh_dmac->channel[info->chan].chcr;
+	struct dma_channel *chan = (struct dma_channel *)dev_id;
+	u32 chcr;
+
+	chcr = ctrl_inl(CHCR[chan->chan]);
 
 	if (!(chcr & CHCR_TE))
 		return IRQ_NONE;
 
-	sh_dmac->channel[info->chan].chcr = chcr & ~(CHCR_IE | CHCR_DE);
+	chcr &= ~(CHCR_IE | CHCR_DE);
+	ctrl_outl(chcr, CHCR[chan->chan]);
 
-	wake_up(&info->wait_queue);
+	wake_up(&chan->wait_queue);
 
 	return IRQ_HANDLED;
 }
 
-static int sh_dmac_request_dma(struct dma_info *info)
+static int sh_dmac_request_dma(struct dma_channel *chan)
 {
-	return request_irq(get_dmte_irq(info->chan), dma_tei,
-			   SA_INTERRUPT, "DMAC Transfer End", info);
+	return request_irq(get_dmte_irq(chan->chan), dma_tei,
+			   SA_INTERRUPT, "DMAC Transfer End", chan);
 }
 
-static void sh_dmac_free_dma(struct dma_info *info)
+static void sh_dmac_free_dma(struct dma_channel *chan)
 {
-	free_irq(get_dmte_irq(info->chan), info);
+	free_irq(get_dmte_irq(chan->chan), chan);
 }
 
-static void sh_dmac_configure_channel(struct dma_info *info, unsigned long chcr)
+static void sh_dmac_configure_channel(struct dma_channel *chan, unsigned long chcr)
 {
 	if (!chcr)
 		chcr = RS_DUAL;
 
-	sh_dmac->channel[info->chan].chcr = chcr;
+	ctrl_outl(chcr, CHCR[chan->chan]);
 
-	info->configured = 1;
+	chan->flags |= DMA_CONFIGURED;
 }
 
-static void sh_dmac_enable_dma(struct dma_info *info)
+static void sh_dmac_enable_dma(struct dma_channel *chan)
 {
-	int irq = get_dmte_irq(info->chan);
+	int irq = get_dmte_irq(chan->chan);
+	u32 chcr;
+
+	chcr = ctrl_inl(CHCR[chan->chan]);
+	chcr |= CHCR_DE | CHCR_IE;
+	ctrl_outl(chcr, CHCR[chan->chan]);
 
-	sh_dmac->channel[info->chan].chcr |= (CHCR_DE | CHCR_IE);
 	enable_irq(irq);
 }
 
-static void sh_dmac_disable_dma(struct dma_info *info)
+static void sh_dmac_disable_dma(struct dma_channel *chan)
 {
-	int irq = get_dmte_irq(info->chan);
+	int irq = get_dmte_irq(chan->chan);
+	u32 chcr;
 
 	disable_irq(irq);
-	sh_dmac->channel[info->chan].chcr &= ~(CHCR_DE | CHCR_TE | CHCR_IE);
+
+	chcr = ctrl_inl(CHCR[chan->chan]);
+	chcr &= ~(CHCR_DE | CHCR_TE | CHCR_IE);
+	ctrl_outl(chcr, CHCR[chan->chan]);
 }
 
-static int sh_dmac_xfer_dma(struct dma_info *info)
+static int sh_dmac_xfer_dma(struct dma_channel *chan)
 {
 	/*
 	 * If we haven't pre-configured the channel with special flags, use
 	 * the defaults.
 	 */
-	if (!info->configured)
-		sh_dmac_configure_channel(info, 0);
+	if (!(chan->flags & DMA_CONFIGURED))
+		sh_dmac_configure_channel(chan, 0);
 
-	sh_dmac_disable_dma(info);
+	sh_dmac_disable_dma(chan);
 
 	/*
 	 * Single-address mode usage note!
@@ -177,33 +178,36 @@ static int sh_dmac_xfer_dma(struct dma_info *info)
 	 * cascading to the PVR2 DMAC. In this case, we still need to write
 	 * SAR and DAR, regardless of value, in order for cascading to work.
 	 */
-	if (info->sar || (mach_is_dreamcast() && info->chan == 2))
-		sh_dmac->channel[info->chan].sar = info->sar;
-	if (info->dar || (mach_is_dreamcast() && info->chan == 2))
-		sh_dmac->channel[info->chan].dar = info->dar;
+	if (chan->sar || (mach_is_dreamcast() && chan->chan == 2))
+		ctrl_outl(chan->sar, SAR[chan->chan]);
+	if (chan->dar || (mach_is_dreamcast() && chan->chan == 2))
+		ctrl_outl(chan->dar, DAR[chan->chan]);
 
-	sh_dmac->channel[info->chan].dmatcr = info->count >> calc_xmit_shift(info);
+	ctrl_outl(chan->count >> calc_xmit_shift(chan), DMATCR[chan->chan]);
 
-	sh_dmac_enable_dma(info);
+	sh_dmac_enable_dma(chan);
 
 	return 0;
 }
 
-static int sh_dmac_get_dma_residue(struct dma_info *info)
+static int sh_dmac_get_dma_residue(struct dma_channel *chan)
 {
-	if (!(sh_dmac->channel[info->chan].chcr & CHCR_DE))
+	if (!(ctrl_inl(CHCR[chan->chan]) & CHCR_DE))
 		return 0;
 
-	return sh_dmac->channel[info->chan].dmatcr << calc_xmit_shift(info);
+	return ctrl_inl(DMATCR[chan->chan]) << calc_xmit_shift(chan);
 }
 
 #if defined(CONFIG_CPU_SH4)
 static irqreturn_t dma_err(int irq, void *dev_id, struct pt_regs *regs)
 {
-	printk("DMAE: DMAOR=%lx\n", sh_dmac->dmaor);
+	unsigned long dmaor = ctrl_inl(DMAOR);
 
-	sh_dmac->dmaor &= ~(DMAOR_NMIF | DMAOR_AE);
-	sh_dmac->dmaor |= DMAOR_DME;
+	printk("DMAE: DMAOR=%lx\n", dmaor);
+
+	ctrl_outl(ctrl_inl(DMAOR)&~DMAOR_NMIF, DMAOR);
+	ctrl_outl(ctrl_inl(DMAOR)&~DMAOR_AE, DMAOR);
+	ctrl_outl(ctrl_inl(DMAOR)|DMAOR_DME, DMAOR);
 
 	disable_irq(irq);
 
@@ -212,7 +216,6 @@ static irqreturn_t dma_err(int irq, void *dev_id, struct pt_regs *regs)
 #endif
 
 static struct dma_ops sh_dmac_ops = {
-	.name		= "SuperH DMAC",
 	.request	= sh_dmac_request_dma,
 	.free		= sh_dmac_free_dma,
 	.get_residue	= sh_dmac_get_dma_residue,
@@ -220,8 +223,16 @@ static struct dma_ops sh_dmac_ops = {
 	.configure	= sh_dmac_configure_channel,
 };
 
+static struct dma_info sh_dmac_info = {
+	.name		= "SuperH DMAC",
+	.nr_channels	= 4,
+	.ops		= &sh_dmac_ops,
+	.flags		= DMAC_CHANNELS_TEI_CAPABLE,
+};
+
 static int __init sh_dmac_init(void)
 {
+	struct dma_info *info = &sh_dmac_info;
 	int i;
 
 #ifdef CONFIG_CPU_SH4
@@ -231,18 +242,15 @@ static int __init sh_dmac_init(void)
 		return i;
 #endif
 
-	for (i = 0; i < MAX_DMAC_CHANNELS; i++) {
+	for (i = 0; i < info->nr_channels; i++) {
 		int irq = get_dmte_irq(i);
 
 		make_ipr_irq(irq, DMA_IPR_ADDR, DMA_IPR_POS, DMA_PRIORITY);
-
-		dma_info[i].ops = &sh_dmac_ops;
-		dma_info[i].tei_capable = 1;
 	}
 
-	sh_dmac->dmaor |= 0x8000 | DMAOR_DME;
+	ctrl_outl(0x8000 | DMAOR_DME, DMAOR);
 
-	return register_dmac(&sh_dmac_ops);
+	return register_dmac(info);
 }
 
 static void __exit sh_dmac_exit(void)

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

+/*
+ * arch/sh/drivers/dma/dma-sysfs.c
+ *
+ * sysfs interface for SH DMA API
+ *
+ * Copyright (C) 2004  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
+ * for more details.
+ */
+#include <linux/kernel.h>
+#include <linux/init.h>
+#include <linux/sysdev.h>
+#include <linux/module.h>
+#include <asm/dma.h>
+
+static struct sysdev_class dma_sysclass = {
+	set_kset_name("dma"),
+};
+
+EXPORT_SYMBOL(dma_sysclass);
+
+static ssize_t dma_show_devices(struct sys_device *dev, char *buf)
+{
+	ssize_t len = 0;
+	int i;
+
+	for (i = 0; i < MAX_DMA_CHANNELS; i++) {
+		struct dma_info *info = get_dma_info(i);
+		struct dma_channel *channel = &info->channels[i];
+
+		len += sprintf(buf + len, "%2d: %14s    %s\n",
+			       channel->chan, info->name,
+			       channel->dev_id);
+	}
+
+	return len;
+}
+
+static SYSDEV_ATTR(devices, S_IRUGO, dma_show_devices, NULL);
+
+static int __init dma_sysclass_init(void)
+{
+	int ret;
+
+	ret = sysdev_class_register(&dma_sysclass);
+	if (ret == 0)
+		sysfs_create_file(&dma_sysclass.kset.kobj, &attr_devices.attr);
+
+	return ret;
+}
+
+postcore_initcall(dma_sysclass_init);
+
+static ssize_t dma_show_dev_id(struct sys_device *dev, char *buf)
+{
+	struct dma_channel *channel = to_dma_channel(dev);
+	return sprintf(buf, "%s\n", channel->dev_id);
+}
+
+static ssize_t dma_store_dev_id(struct sys_device *dev,
+				const char *buf, size_t count)
+{
+	struct dma_channel *channel = to_dma_channel(dev);
+	strcpy(channel->dev_id, buf);
+	return count;
+}
+
+static SYSDEV_ATTR(dev_id, S_IRUGO | S_IWUSR, dma_show_dev_id, dma_store_dev_id);
+
+static ssize_t dma_store_config(struct sys_device *dev,
+				const char *buf, size_t count)
+{
+	struct dma_channel *channel = to_dma_channel(dev);
+	unsigned long config;
+
+	config = simple_strtoul(buf, NULL, 0);
+	dma_configure_channel(channel->chan, config);
+
+	return count;
+}
+
+static SYSDEV_ATTR(config, S_IWUSR, NULL, dma_store_config);
+
+static ssize_t dma_show_mode(struct sys_device *dev, char *buf)
+{
+	struct dma_channel *channel = to_dma_channel(dev);
+	return sprintf(buf, "0x%08x\n", channel->mode);
+}
+
+static ssize_t dma_store_mode(struct sys_device *dev,
+			      const char *buf, size_t count)
+{
+	struct dma_channel *channel = to_dma_channel(dev);
+	channel->mode = simple_strtoul(buf, NULL, 0);
+	return count;
+}
+
+static SYSDEV_ATTR(mode, S_IRUGO | S_IWUSR, dma_show_mode, dma_store_mode);
+
+#define dma_ro_attr(field, fmt)						\
+static ssize_t dma_show_##field(struct sys_device *dev, char *buf)	\
+{									\
+	struct dma_channel *channel = to_dma_channel(dev);		\
+	return sprintf(buf, fmt, channel->field);			\
+}									\
+static SYSDEV_ATTR(field, S_IRUGO, dma_show_##field, NULL);
+
+dma_ro_attr(count, "0x%08x\n");
+dma_ro_attr(flags, "0x%08lx\n");
+
+int __init dma_create_sysfs_files(struct dma_channel *chan)
+{
+	struct sys_device *dev = &chan->dev;
+	int ret;
+
+	dev->id  = chan->chan;
+	dev->cls = &dma_sysclass;
+
+	ret = sysdev_register(dev);
+	if (ret)
+		return ret;
+
+	sysdev_create_file(dev, &attr_dev_id);
+	sysdev_create_file(dev, &attr_count);
+	sysdev_create_file(dev, &attr_mode);
+	sysdev_create_file(dev, &attr_flags);
+	sysdev_create_file(dev, &attr_config);
+
+	return 0;
+}
+

include/asm-sh/cpu-sh4/dma.h

@@ -3,5 +3,15 @@
 
 #define SH_DMAC_BASE	0xffa00000
 
+#define SAR	((unsigned long[]){SH_DMAC_BASE + 0x00, SH_DMAC_BASE + 0x10, \
+				   SH_DMAC_BASE + 0x20, SH_DMAC_BASE + 0x30})
+#define DAR	((unsigned long[]){SH_DMAC_BASE + 0x04, SH_DMAC_BASE + 0x14, \
+				   SH_DMAC_BASE + 0x24, SH_DMAC_BASE + 0x34})
+#define DMATCR	((unsigned long[]){SH_DMAC_BASE + 0x08, SH_DMAC_BASE + 0x18, \
+				   SH_DMAC_BASE + 0x28, SH_DMAC_BASE + 0x38})
+#define CHCR	((unsigned long[]){SH_DMAC_BASE + 0x0c, SH_DMAC_BASE + 0x1c, \
+				   SH_DMAC_BASE + 0x2c, SH_DMAC_BASE + 0x3c})
+#define DMAOR	(SH_DMAC_BASE + 0x40)
+
 #endif /* __ASM_CPU_SH4_DMA_H */
 

include/asm-sh/dma.h

 /*
  * include/asm-sh/dma.h
  *
- * Copyright (C) 2003  Paul Mundt
+ * Copyright (C) 2003, 2004  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
@@ -13,6 +13,7 @@
 #include <linux/config.h>
 #include <linux/spinlock.h>
 #include <linux/wait.h>
+#include <linux/sysdev.h>
 #include <asm/cpu/dma.h>
 #include <asm/semaphore.h>
 
@@ -38,23 +39,39 @@
 #define DMA_MODE_WRITE		0x01
 #define DMA_MODE_MASK		0x01
 
+#define DMA_AUTOINIT		0x10
+
+/*
+ * DMAC (dma_info) flags
+ */
+enum {
+	DMAC_CHANNELS_CONFIGURED	= 0x00,
+	DMAC_CHANNELS_TEI_CAPABLE	= 0x01,
+};
+
+/*
+ * DMA channel capabilities / flags
+ */
+enum {
+	DMA_CONFIGURED			= 0x00,
+	DMA_TEI_CAPABLE			= 0x01,
+};
+
 extern spinlock_t dma_spin_lock;
 
-struct dma_info;
+struct dma_channel;
 
 struct dma_ops {
-	const char *name;
-
-	int (*request)(struct dma_info *info);
-	void (*free)(struct dma_info *info);
+	int (*request)(struct dma_channel *chan);
+	void (*free)(struct dma_channel *chan);
 
-	int (*get_residue)(struct dma_info *info);
-	int (*xfer)(struct dma_info *info);
-	void (*configure)(struct dma_info *info, unsigned long flags);
+	int (*get_residue)(struct dma_channel *chan);
+	int (*xfer)(struct dma_channel *chan);
+	void (*configure)(struct dma_channel *chan, unsigned long flags);
 };
 
-struct dma_info {
-	const char *dev_id;
+struct dma_channel {
+	char dev_id[16];
 
 	unsigned int chan;
 	unsigned int mode;
@@ -63,15 +80,28 @@ struct dma_info {
 	unsigned long sar;
 	unsigned long dar;
 
-	unsigned int configured:1;
-	unsigned int tei_capable:1;
+	unsigned long flags;
 	atomic_t busy;
 
 	struct semaphore sem;
 	wait_queue_head_t wait_queue;
+
+	struct sys_device dev;
+};
+
+struct dma_info {
+	const char *name;
+	unsigned int nr_channels;
+	unsigned long flags;
+
 	struct dma_ops *ops;
+	struct dma_channel *channels;
+
+	struct list_head list;
 };
 
+#define to_dma_channel(channel) container_of(channel, struct dma_channel, dev)
+
 /* arch/sh/drivers/dma/dma-api.c */
 extern int dma_xfer(unsigned int chan, unsigned long from,
 		    unsigned long to, size_t size, unsigned int mode);
@@ -90,12 +120,17 @@ extern int request_dma(unsigned int chan, const char *dev_id);
 extern void free_dma(unsigned int chan);
 extern int get_dma_residue(unsigned int chan);
 extern struct dma_info *get_dma_info(unsigned int chan);
+extern struct dma_channel *get_dma_channel(unsigned int chan);
 extern void dma_wait_for_completion(unsigned int chan);
 extern void dma_configure_channel(unsigned int chan, unsigned long flags);
 
-extern int register_dmac(struct dma_ops *ops);
+extern int register_dmac(struct dma_info *info);
+extern void unregister_dmac(struct dma_info *info);
 
-extern struct dma_info dma_info[];
+#ifdef CONFIG_SYSFS
+/* arch/sh/drivers/dma/dma-sysfs.c */
+extern int dma_create_sysfs_files(struct dma_channel *);
+#endif
 
 #ifdef CONFIG_PCI
 extern int isa_dma_bridge_buggy;