[PATCH 6/9 v6] V4L: sh-mobile-ceu-camera: prepare to support multi-size buffers

[Guennadi Liakhovetski <g.liakhovetski@gmx.de>]

Prepare the sh_mobile_ceu_camera friver to support the new
VIDIOC_CREATE_BUFS and VIDIOC_PREPARE_BUF ioctl()s. The .queue_setup()
vb2 operation must be able to handle buffer sizes, provided by the
caller, and the .buf_prepare() operation must not use the currently
configured frame format for its operation.

Signed-off-by: Guennadi Liakhovetski <g.liakhovetski@gmx.de>
Cc: Hans Verkuil <hverkuil@xs4all.nl>
Cc: Laurent Pinchart <laurent.pinchart@ideasonboard.com>
Cc: Marek Szyprowski <m.szyprowski@samsung.com>
Cc: Mauro Carvalho Chehab <mchehab@infradead.org>
Cc: Pawel Osciak <pawel@osciak.com>
Cc: Sakari Ailus <sakari.ailus@maxwell.research.nokia.com>
---

v6: Handle the case of VIDIOC_CREATE_BUFS, when vb2 creates fewer buffers, than
    requested by the user, correctly

 drivers/media/video/sh_mobile_ceu_camera.c |  122 ++++++++++++++++++----------
 1 files changed, 79 insertions(+), 43 deletions(-)

diff --git a/drivers/media/video/sh_mobile_ceu_camera.c b/drivers/media/video/sh_mobile_ceu_camera.c
index db3a24d..56bb82d 100644
--- a/drivers/media/video/sh_mobile_ceu_camera.c
+++ b/drivers/media/video/sh_mobile_ceu_camera.c
@@ -90,7 +90,6 @@
 struct sh_mobile_ceu_buffer {
 	struct vb2_buffer vb; /* v4l buffer must be first */
 	struct list_head queue;
-	enum v4l2_mbus_pixelcode code;
 };
 
 struct sh_mobile_ceu_dev {
@@ -100,7 +99,8 @@ struct sh_mobile_ceu_dev {
 
 	unsigned int irq;
 	void __iomem *base;
-	unsigned long video_limit;
+	size_t video_limit;
+	size_t buf_total;
 
 	spinlock_t lock;		/* Protects video buffer lists */
 	struct list_head capture;
@@ -192,6 +192,12 @@ static int sh_mobile_ceu_soft_reset(struct sh_mobile_ceu_dev *pcdev)
 /*
  *  Videobuf operations
  */
+
+/*
+ * .queue_setup() is called to check, whether the driver can accept the
+ *		  requested number of buffers and to fill in plane sizes
+ *		  for the current frame format if required
+ */
 static int sh_mobile_ceu_videobuf_setup(struct vb2_queue *vq,
 			const struct v4l2_format *fmt,
 			unsigned int *count, unsigned int *num_planes,
@@ -200,26 +206,45 @@ static int sh_mobile_ceu_videobuf_setup(struct vb2_queue *vq,
 	struct soc_camera_device *icd = container_of(vq, struct soc_camera_device, vb2_vidq);
 	struct soc_camera_host *ici = to_soc_camera_host(icd->parent);
 	struct sh_mobile_ceu_dev *pcdev = ici->priv;
-	int bytes_per_line = soc_mbus_bytes_per_line(icd->user_width,
-						icd->current_fmt->host_fmt);
+	int bytes_per_line;
+	unsigned int height;
 
+	if (fmt) {
+		const struct soc_camera_format_xlate *xlate = soc_camera_xlate_by_fourcc(icd,
+								fmt->fmt.pix.pixelformat);
+		bytes_per_line = soc_mbus_bytes_per_line(fmt->fmt.pix.width,
+							 xlate->host_fmt);
+		height = fmt->fmt.pix.height;
+	} else {
+		/* Called from VIDIOC_REQBUFS or in compatibility mode */
+		bytes_per_line = soc_mbus_bytes_per_line(icd->user_width,
+						icd->current_fmt->host_fmt);
+		height = icd->user_height;
+	}
 	if (bytes_per_line < 0)
 		return bytes_per_line;
 
-	*num_planes = 1;
+	sizes[0] = bytes_per_line * height;
 
-	pcdev->sequence = 0;
-	sizes[0] = bytes_per_line * icd->user_height;
 	alloc_ctxs[0] = pcdev->alloc_ctx;
 
+	if (!vq->num_buffers)
+		pcdev->sequence = 0;
+
 	if (!*count)
 		*count = 2;
 
-	if (pcdev->video_limit) {
-		if (PAGE_ALIGN(sizes[0]) * *count > pcdev->video_limit)
-			*count = pcdev->video_limit / PAGE_ALIGN(sizes[0]);
+	/* If *num_planes != 0, we have already verified *count. */
+	if (pcdev->video_limit && !*num_planes) {
+		size_t size = PAGE_ALIGN(sizes[0]) * *count;
+
+		if (size + pcdev->buf_total > pcdev->video_limit)
+			*count = (pcdev->video_limit - pcdev->buf_total) /
+				PAGE_ALIGN(sizes[0]);
 	}
 
+	*num_planes = 1;
+
 	dev_dbg(icd->parent, "count=%d, size=%lu\n", *count, sizes[0]);
 
 	return 0;
@@ -331,23 +356,40 @@ static int sh_mobile_ceu_capture(struct sh_mobile_ceu_dev *pcdev)
 
 static int sh_mobile_ceu_videobuf_prepare(struct vb2_buffer *vb)
 {
+	struct sh_mobile_ceu_buffer *buf = to_ceu_vb(vb);
+
+	/* Added list head initialization on alloc */
+	WARN(!list_empty(&buf->queue), "Buffer %p on queue!\n", vb);
+
+	return 0;
+}
+
+static void sh_mobile_ceu_videobuf_queue(struct vb2_buffer *vb)
+{
 	struct soc_camera_device *icd = container_of(vb->vb2_queue, struct soc_camera_device, vb2_vidq);
-	struct sh_mobile_ceu_buffer *buf;
+	struct soc_camera_host *ici = to_soc_camera_host(icd->parent);
+	struct sh_mobile_ceu_dev *pcdev = ici->priv;
+	struct sh_mobile_ceu_buffer *buf = to_ceu_vb(vb);
+	unsigned long size;
 	int bytes_per_line = soc_mbus_bytes_per_line(icd->user_width,
 						icd->current_fmt->host_fmt);
-	unsigned long size;
 
 	if (bytes_per_line < 0)
-		return bytes_per_line;
+		goto error;
+
+	size = icd->user_height * bytes_per_line;
+
+	if (vb2_plane_size(vb, 0) < size) {
+		dev_err(icd->parent, "Buffer #%d too small (%lu < %lu)\n",
+			vb->v4l2_buf.index, vb2_plane_size(vb, 0), size);
+		goto error;
+	}
 
-	buf = to_ceu_vb(vb);
+	vb2_set_plane_payload(vb, 0, size);
 
 	dev_dbg(icd->parent, "%s (vb=0x%p) 0x%p %lu\n", __func__,
 		vb, vb2_plane_vaddr(vb, 0), vb2_get_plane_payload(vb, 0));
 
-	/* Added list head initialization on alloc */
-	WARN(!list_empty(&buf->queue), "Buffer %p on queue!\n", vb);
-
 #ifdef DEBUG
 	/*
 	 * This can be useful if you want to see if we actually fill
@@ -357,31 +399,6 @@ static int sh_mobile_ceu_videobuf_prepare(struct vb2_buffer *vb)
 		memset(vb2_plane_vaddr(vb, 0), 0xaa, vb2_get_plane_payload(vb, 0));
 #endif
 
-	BUG_ON(NULL == icd->current_fmt);
-
-	size = icd->user_height * bytes_per_line;
-
-	if (vb2_plane_size(vb, 0) < size) {
-		dev_err(icd->parent, "Buffer too small (%lu < %lu)\n",
-			vb2_plane_size(vb, 0), size);
-		return -ENOBUFS;
-	}
-
-	vb2_set_plane_payload(vb, 0, size);
-
-	return 0;
-}
-
-static void sh_mobile_ceu_videobuf_queue(struct vb2_buffer *vb)
-{
-	struct soc_camera_device *icd = container_of(vb->vb2_queue, struct soc_camera_device, vb2_vidq);
-	struct soc_camera_host *ici = to_soc_camera_host(icd->parent);
-	struct sh_mobile_ceu_dev *pcdev = ici->priv;
-	struct sh_mobile_ceu_buffer *buf = to_ceu_vb(vb);
-
-	dev_dbg(icd->parent, "%s (vb=0x%p) 0x%p %lu\n", __func__,
-		vb, vb2_plane_vaddr(vb, 0), vb2_get_plane_payload(vb, 0));
-
 	spin_lock_irq(&pcdev->lock);
 	list_add_tail(&buf->queue, &pcdev->capture);
 
@@ -395,6 +412,11 @@ static void sh_mobile_ceu_videobuf_queue(struct vb2_buffer *vb)
 		sh_mobile_ceu_capture(pcdev);
 	}
 	spin_unlock_irq(&pcdev->lock);
+
+	return;
+
+error:
+	vb2_buffer_done(vb, VB2_BUF_STATE_ERROR);
 }
 
 static void sh_mobile_ceu_videobuf_release(struct vb2_buffer *vb)
@@ -419,11 +441,23 @@ static void sh_mobile_ceu_videobuf_release(struct vb2_buffer *vb)
 	if (buf->queue.next)
 		list_del_init(&buf->queue);
 
+	pcdev->buf_total -= PAGE_ALIGN(vb2_plane_size(vb, 0));
+	dev_dbg(icd->parent, "%s() %zu bytes buffers\n", __func__,
+		pcdev->buf_total);
+
 	spin_unlock_irq(&pcdev->lock);
 }
 
 static int sh_mobile_ceu_videobuf_init(struct vb2_buffer *vb)
 {
+	struct soc_camera_device *icd = container_of(vb->vb2_queue, struct soc_camera_device, vb2_vidq);
+	struct soc_camera_host *ici = to_soc_camera_host(icd->parent);
+	struct sh_mobile_ceu_dev *pcdev = ici->priv;
+
+	pcdev->buf_total += PAGE_ALIGN(vb2_plane_size(vb, 0));
+	dev_dbg(icd->parent, "%s() %zu bytes buffers\n", __func__,
+		pcdev->buf_total);
+
 	/* This is for locking debugging only */
 	INIT_LIST_HEAD(&to_ceu_vb(vb)->queue);
 	return 0;
@@ -525,6 +559,8 @@ static int sh_mobile_ceu_add_device(struct soc_camera_device *icd)
 
 	pm_runtime_get_sync(ici->v4l2_dev.dev);
 
+	pcdev->buf_total = 0;
+
 	ret = sh_mobile_ceu_soft_reset(pcdev);
 
 	csi2_sd = find_csi2(pcdev);
@@ -1674,7 +1710,7 @@ static int sh_mobile_ceu_set_fmt(struct soc_camera_device *icd,
 		image_mode = false;
 	}
 
-	dev_info(dev, "S_FMT(pix=0x%x, fld 0x%x, code 0x%x, %ux%u)\n", pixfmt, mf.field, mf.code,
+	dev_geo(dev, "S_FMT(pix=0x%x, fld 0x%x, code 0x%x, %ux%u)\n", pixfmt, mf.field, mf.code,
 		pix->width, pix->height);
 
 	dev_geo(dev, "4: request camera output %ux%u\n", mf.width, mf.height);
-- 
1.7.2.5