[RESEND/PATCH,2/6] tw686x: Add support for DMA contiguous interlaced frame mode

Commit Message

Ezequiel Garcia June 4, 2016, 11:47 p.m. UTC

Now that the driver has the infrastructure to support more
DMA modes, let's add the DMA contiguous interlaced frame mode.

In this mode, the DMA P and B buffers are programmed with
the user-provided buffers. When a P (or B) frame is ready,
a new buffer is dequeued into P (or B).

In addition to interlaced fields, the device can also be
programmed to deliver alternate fields. Only interlaced
mode is supported for now.

Tested-by: Tim Harvey <[e-mail]>
Signed-off-by: Ezequiel Garcia <[e-mail]>
---
 drivers/media/pci/tw686x/Kconfig        |  1 +
 drivers/media/pci/tw686x/tw686x-core.c  |  4 +++
 drivers/media/pci/tw686x/tw686x-video.c | 50 +++++++++++++++++++++++++++++++++
 drivers/media/pci/tw686x/tw686x.h       |  1 +
 4 files changed, 56 insertions(+)

Patch

diff --git a/drivers/media/pci/tw686x/Kconfig b/drivers/media/pci/tw686x/Kconfig
index fb8536974052..ef8ca85522f8 100644
--- a/drivers/media/pci/tw686x/Kconfig
+++ b/drivers/media/pci/tw686x/Kconfig
@@ -3,6 +3,7 @@  config VIDEO_TW686X
 	depends on PCI && VIDEO_DEV && VIDEO_V4L2 && SND
 	depends on HAS_DMA
 	select VIDEOBUF2_VMALLOC
+	select VIDEOBUF2_DMA_CONTIG
 	select SND_PCM
 	help
 	  Support for Intersil/Techwell TW686x-based frame grabber cards.
diff --git a/drivers/media/pci/tw686x/tw686x-core.c b/drivers/media/pci/tw686x/tw686x-core.c
index 01c06bb59e78..9a7646c0f9f6 100644
--- a/drivers/media/pci/tw686x/tw686x-core.c
+++ b/drivers/media/pci/tw686x/tw686x-core.c
@@ -63,6 +63,8 @@  static const char *dma_mode_name(unsigned int mode)
 	switch (mode) {
 	case TW686X_DMA_MODE_MEMCPY:
 		return "memcpy";
+	case TW686X_DMA_MODE_CONTIG:
+		return "contig";
 	default:
 		return "unknown";
 	}
@@ -77,6 +79,8 @@  static int tw686x_dma_mode_set(const char *val, struct kernel_param *kp)
 {
 	if (!strcasecmp(val, dma_mode_name(TW686X_DMA_MODE_MEMCPY)))
 		dma_mode = TW686X_DMA_MODE_MEMCPY;
+	else if (!strcasecmp(val, dma_mode_name(TW686X_DMA_MODE_CONTIG)))
+		dma_mode = TW686X_DMA_MODE_CONTIG;
 	else
 		return -EINVAL;
 	return 0;
diff --git a/drivers/media/pci/tw686x/tw686x-video.c b/drivers/media/pci/tw686x/tw686x-video.c
index c0d2a9bd5414..b5cb385e4cb1 100644
--- a/drivers/media/pci/tw686x/tw686x-video.c
+++ b/drivers/media/pci/tw686x/tw686x-video.c
@@ -19,6 +19,7 @@ 
 #include <linux/slab.h>
 #include <media/v4l2-common.h>
 #include <media/v4l2-event.h>
+#include <media/videobuf2-dma-contig.h>
 #include <media/videobuf2-vmalloc.h>
 #include "tw686x.h"
 #include "tw686x-regs.h"
@@ -148,6 +149,53 @@  const struct tw686x_dma_ops memcpy_dma_ops = {
 	.field		= V4L2_FIELD_INTERLACED,
 };
 
+static void tw686x_contig_buf_refill(struct tw686x_video_channel *vc,
+				     unsigned int pb)
+{
+	struct tw686x_v4l2_buf *buf;
+
+	while (!list_empty(&vc->vidq_queued)) {
+		u32 reg = pb ? VDMA_B_ADDR[vc->ch] : VDMA_P_ADDR[vc->ch];
+		dma_addr_t phys;
+
+		buf = list_first_entry(&vc->vidq_queued,
+			struct tw686x_v4l2_buf, list);
+		list_del(&buf->list);
+
+		phys = vb2_dma_contig_plane_dma_addr(&buf->vb.vb2_buf, 0);
+		reg_write(vc->dev, reg, phys);
+
+		buf->vb.vb2_buf.state = VB2_BUF_STATE_ACTIVE;
+		vc->curr_bufs[pb] = buf;
+		return;
+	}
+	vc->curr_bufs[pb] = NULL;
+}
+
+static void tw686x_contig_cleanup(struct tw686x_dev *dev)
+{
+	vb2_dma_contig_cleanup_ctx(dev->alloc_ctx);
+}
+
+static int tw686x_contig_setup(struct tw686x_dev *dev)
+{
+	dev->alloc_ctx = vb2_dma_contig_init_ctx(&dev->pci_dev->dev);
+	if (IS_ERR(dev->alloc_ctx)) {
+		dev_err(&dev->pci_dev->dev, "unable to init DMA context\n");
+		return PTR_ERR(dev->alloc_ctx);
+	}
+	return 0;
+}
+
+const struct tw686x_dma_ops contig_dma_ops = {
+	.setup		= tw686x_contig_setup,
+	.cleanup	= tw686x_contig_cleanup,
+	.buf_refill	= tw686x_contig_buf_refill,
+	.mem_ops	= &vb2_dma_contig_memops,
+	.hw_dma_mode	= TW686X_FRAME_MODE,
+	.field		= V4L2_FIELD_INTERLACED,
+};
+
 static unsigned int tw686x_fields_map(v4l2_std_id std, unsigned int fps)
 {
 	static const unsigned int map[15] = {
@@ -841,6 +889,8 @@  int tw686x_video_init(struct tw686x_dev *dev)
 
 	if (dev->dma_mode == TW686X_DMA_MODE_MEMCPY)
 		dev->dma_ops = &memcpy_dma_ops;
+	else if (dev->dma_mode == TW686X_DMA_MODE_CONTIG)
+		dev->dma_ops = &contig_dma_ops;
 	else
 		return -EINVAL;
 
diff --git a/drivers/media/pci/tw686x/tw686x.h b/drivers/media/pci/tw686x/tw686x.h
index 977ff6e3c1e2..5f4c2131ddac 100644
--- a/drivers/media/pci/tw686x/tw686x.h
+++ b/drivers/media/pci/tw686x/tw686x.h
@@ -33,6 +33,7 @@ 
 #define TW686X_AUDIO_PERIODS_MAX	TW686X_AUDIO_PAGE_MAX
 
 #define TW686X_DMA_MODE_MEMCPY		0
+#define TW686X_DMA_MODE_CONTIG		1
 
 struct tw686x_format {
 	char *name;