ENGR00121221 MX28 DMA: Support circular dma chain used on audio playback

Support circular DMA which will be used on audio playback/record.

Signed-off-by: Lionel Xu <r63889@freescale.com>
(cherry picked from commit 68e74123a031794578464b8a16d4f704fc8e7960)
Signed-off-by: Alejandro Gonzalez <alex.gonzalez@digi.com>

4 files changed, 89 insertions, 9 deletions

diff --git a/arch/arm/plat-mxs/dma-apbh.c b/arch/arm/plat-mxs/dma-apbh.c
index 9dfcadde02c9..7689f8e3f362 100644
--- a/arch/arm/plat-mxs/dma-apbh.c
+++ b/arch/arm/plat-mxs/dma-apbh.c
@@ -28,7 +28,6 @@
 
 #include <mach/device.h>
 #include <mach/dmaengine.h>
-#include <mach/hardware.h>
 
 #include "regs-apbh.h"
 
@@ -94,6 +93,15 @@ mxs_dma_apbh_unfreeze(struct mxs_dma_device *pdev, unsigned int chan)
 	__raw_writel(1 << chan, pdev->base + HW_APBH_CHANNEL_CTRL_CLR);
 }
 
+static void mxs_dma_apbh_info(struct mxs_dma_device *pdev,
+		unsigned int chan, struct mxs_dma_info *info)
+{
+	unsigned int reg;
+	reg = __raw_readl(pdev->base + HW_APBH_CTRL2);
+	info->status = reg >> chan;
+	info->buf_addr = __raw_readl(pdev->base + HW_APBH_CHn_BAR(chan));
+}
+
 static int
 mxs_dma_apbh_read_semaphore(struct mxs_dma_device *pdev, unsigned int chan)
 {
@@ -137,6 +145,7 @@ static struct mxs_dma_device mxs_dma_apbh = {
 	.reset = mxs_dma_apbh_reset,
 	.freeze = mxs_dma_apbh_freeze,
 	.unfreeze = mxs_dma_apbh_unfreeze,
+	.info = mxs_dma_apbh_info,
 	.read_semaphore = mxs_dma_apbh_read_semaphore,
 	.enable_irq = mxs_dma_apbh_enable_irq,
 	.irq_is_pending = mxs_dma_apbh_irq_is_pending,
diff --git a/arch/arm/plat-mxs/dma-apbx.c b/arch/arm/plat-mxs/dma-apbx.c
index 6f412310648c..b38298ba152a 100644
--- a/arch/arm/plat-mxs/dma-apbx.c
+++ b/arch/arm/plat-mxs/dma-apbx.c
@@ -28,7 +28,6 @@
 
 #include <mach/device.h>
 #include <mach/dmaengine.h>
-#include <mach/hardware.h>
 
 #include "regs-apbx.h"
 
@@ -92,6 +91,15 @@ mxs_dma_apbx_unfreeze(struct mxs_dma_device *pdev, unsigned int chan)
 	__raw_writel(1 << chan, pdev->base + HW_APBX_CHANNEL_CTRL_CLR);
 }
 
+static void mxs_dma_apbx_info(struct mxs_dma_device *pdev,
+		unsigned int chan, struct mxs_dma_info *info)
+{
+	unsigned int reg;
+	reg = __raw_readl(pdev->base + HW_APBX_CTRL2);
+	info->status = reg >> chan;
+	info->buf_addr = __raw_readl(pdev->base + HW_APBX_CHn_BAR(chan));
+}
+
 static int
 mxs_dma_apbx_read_semaphore(struct mxs_dma_device *pdev, unsigned int chan)
 {
@@ -135,6 +143,7 @@ static struct mxs_dma_device mxs_dma_apbx = {
 	.reset = mxs_dma_apbx_reset,
 	.freeze = mxs_dma_apbx_freeze,
 	.unfreeze = mxs_dma_apbx_unfreeze,
+	.info = mxs_dma_apbx_info,
 	.read_semaphore = mxs_dma_apbx_read_semaphore,
 	.enable_irq = mxs_dma_apbx_enable_irq,
 	.irq_is_pending = mxs_dma_apbx_irq_is_pending,
diff --git a/arch/arm/plat-mxs/dmaengine.c b/arch/arm/plat-mxs/dmaengine.c
index eaa522e13079..453346e4057f 100644
--- a/arch/arm/plat-mxs/dmaengine.c
+++ b/arch/arm/plat-mxs/dmaengine.c
@@ -165,6 +165,25 @@ void mxs_dma_disable(int channel)
 }
 EXPORT_SYMBOL(mxs_dma_disable);
 
+int mxs_dma_get_info(int channel, struct mxs_dma_info *info)
+{
+	struct mxs_dma_chan *pchan;
+	struct mxs_dma_device *pdma;
+
+	if (!info)
+		return -EINVAL;
+	if ((channel < 0) || (channel >= MAX_DMA_CHANNELS))
+		return -EINVAL;
+	pchan = mxs_dma_channels + channel;
+	if (!(pchan->flags & MXS_DMA_FLAGS_ALLOCATED))
+		return -EFAULT;
+	pdma = pchan->dma;
+	if (pdma->info)
+		pdma->info(pdma, channel - pdma->chan_base, info);
+	return 0;
+}
+EXPORT_SYMBOL(mxs_dma_get_info);
+
 int mxs_dma_cooked(int channel, struct list_head *head)
 {
 	int sem;
@@ -181,6 +200,9 @@ int mxs_dma_cooked(int channel, struct list_head *head)
 	sem = mxs_dma_read_semaphore(channel);
 	if (sem < 0)
 		return sem;
+	if (sem == pchan->active_num)
+		return 0;
+	BUG_ON(sem > pchan->active_num);
 	spin_lock_irqsave(&pchan->lock, flags);
 	list_for_each_safe(p, q, &pchan->active) {
 		if ((pchan->active_num) <= sem)
@@ -191,7 +213,8 @@ int mxs_dma_cooked(int channel, struct list_head *head)
 			list_move_tail(p, head);
 		else
 			list_move_tail(p, &pchan->done);
-		pchan->active_num--;
+		if (pdesc->flags & MXS_DMA_DESC_LAST)
+			pchan->active_num--;
 	}
 	if (sem == 0)
 		pchan->flags &= ~MXS_DMA_FLAGS_BUSY;
@@ -394,21 +417,29 @@ int mxs_dma_desc_append(int channel, struct mxs_dma_desc *pdesc)
 	if (!(pchan->flags & MXS_DMA_FLAGS_ALLOCATED))
 		return -EINVAL;
 	pdma = pchan->dma;
-	pdesc->cmd.next = 0;
+	pdesc->cmd.next = mxs_dma_cmd_address(pdesc);
+	pdesc->flags |= MXS_DMA_DESC_FIRST | MXS_DMA_DESC_LAST;
 	spin_lock_irqsave(&pchan->lock, flags);
 	if (!list_empty(&pchan->active)) {
 		last = list_entry(pchan->active.prev,
 				  struct mxs_dma_desc, node);
+		if (pdesc->cmd.cmd.bits.dec_sem != last->cmd.cmd.bits.dec_sem) {
+			ret = -EFAULT;
+			goto out;
+		}
+		if (!pdesc->cmd.cmd.bits.dec_sem) {
+			pdesc->flags &= ~MXS_DMA_DESC_FIRST;
+			last->flags &= ~MXS_DMA_DESC_LAST;
+		}
 		pdesc->cmd.next = last->cmd.next;
 		last->cmd.next = mxs_dma_cmd_address(pdesc);
-		if (pdesc->cmd.cmd.bits.chain) {
-			last->cmd.cmd.bits.chain = 1;
-			pdesc->cmd.cmd.bits.chain = 0;
-		}
+		last->cmd.cmd.bits.chain = 1;
 	}
 	pdesc->flags |= MXS_DMA_DESC_READY;
-	pchan->pending_num++;
+	if (pdesc->flags & MXS_DMA_DESC_FIRST)
+		pchan->pending_num++;
 	list_add_tail(&pdesc->node, &pchan->active);
+out:
 	spin_unlock_irqrestore(&pchan->lock, flags);
 	return ret;
 }
@@ -434,27 +465,43 @@ int mxs_dma_desc_add_list(int channel, struct list_head *head)
 	pdma = pchan->dma;
 	list_for_each(p, head) {
 		pcur = list_entry(p, struct mxs_dma_desc, node);
+		if (!(pcur->cmd.cmd.bits.dec_sem || pcur->cmd.cmd.bits.chain))
+			return -EINVAL;
 		if (prev)
 			prev->cmd.next = mxs_dma_cmd_address(pcur);
+		else
+			pcur->flags |= MXS_DMA_DESC_FIRST;
 		pcur->flags |= MXS_DMA_DESC_READY;
 		prev = pcur;
 		size++;
 	}
 	pcur = list_first_entry(head, struct mxs_dma_desc, node);
 	prev->cmd.next = mxs_dma_cmd_address(pcur);
+	prev->flags |= MXS_DMA_DESC_LAST;
 
 	spin_lock_irqsave(&pchan->lock, flags);
 	if (!list_empty(&pchan->active)) {
 		pcur = list_entry(pchan->active.next,
 				  struct mxs_dma_desc, node);
+		if (pcur->cmd.cmd.bits.dec_sem != prev->cmd.cmd.bits.dec_sem) {
+			ret = -EFAULT;
+			goto out;
+		}
 		prev->cmd.next = mxs_dma_cmd_address(pcur);
 		prev = list_entry(pchan->active.prev,
 				  struct mxs_dma_desc, node);
 		pcur = list_first_entry(head, struct mxs_dma_desc, node);
+		pcur->flags &= ~MXS_DMA_DESC_FIRST;
+		prev->flags &= ~MXS_DMA_DESC_LAST;
 		prev->cmd.next = mxs_dma_cmd_address(pcur);
 	}
 	list_splice(head, &pchan->active);
 	pchan->pending_num += size;
+	if (!(pcur->cmd.cmd.bits.dec_sem) && (pcur->flags & MXS_DMA_DESC_FIRST))
+		pchan->pending_num += 1;
+	else
+		pchan->pending_num += size;
+out:
 	spin_unlock_irqrestore(&pchan->lock, flags);
 	return ret;
 }
diff --git a/arch/arm/plat-mxs/include/mach/dmaengine.h b/arch/arm/plat-mxs/include/mach/dmaengine.h
index 1071f4e6f674..4bbbcb4b8c85 100644
--- a/arch/arm/plat-mxs/include/mach/dmaengine.h
+++ b/arch/arm/plat-mxs/include/mach/dmaengine.h
@@ -93,11 +93,20 @@ struct mxs_dma_desc {
 	struct mxs_dma_cmd cmd;
 	unsigned int flags;
 #define MXS_DMA_DESC_READY 0x80000000
+#define MXS_DMA_DESC_FIRST 0x00000001
+#define MXS_DMA_DESC_LAST  0x00000002
 	dma_addr_t address;
 	void *buffer;
 	struct list_head node;
 };
 
+struct mxs_dma_info {
+	unsigned int status;
+#define MXS_DMA_INFO_ERR       0x00000001
+#define MXS_DMA_INFO_ERR_STAT  0x00010000
+	unsigned int buf_addr;
+};
+
 /**
  * struct mxs_dma_chan - MXS DMA channel
  *
@@ -176,6 +185,8 @@ struct mxs_dma_device {
 	void (*unfreeze) (struct mxs_dma_device *, unsigned int);
 	int (*read_semaphore) (struct mxs_dma_device *, unsigned int);
 	void (*add_semaphore) (struct mxs_dma_device *, unsigned int, unsigned);
+	void (*info)(struct mxs_dma_device *,
+		unsigned int, struct mxs_dma_info *info);
 	void (*enable_irq) (struct mxs_dma_device *, unsigned int, int);
 	int (*irq_is_pending) (struct mxs_dma_device *, unsigned int);
 	void (*ack_irq) (struct mxs_dma_device *, unsigned int);
@@ -286,8 +297,12 @@ extern void mxs_dma_freeze(int channel);
  * @channel:  The channel number. This is one of the globally unique DMA channel
  *            numbers given in mach/dma.h.
  */
+
 extern void mxs_dma_unfreeze(int channel);
 
+/* get dma channel information */
+extern int mxs_dma_get_info(int channel, struct mxs_dma_info *info);
+
 /**
  * mxs_dma_cooked - Clean up processed DMA descriptors.
  *