[media] V4L: mx3-camera: prepare to support multi-size buffers

Prepare the mx3_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, which makes it superfluous for this driver.
Its functionality is moved into .buf_queue().

Signed-off-by: Guennadi Liakhovetski <g.liakhovetski@gmx.de>
Signed-off-by: Mauro Carvalho Chehab <mchehab@redhat.com>

1 files changed, 85 insertions, 76 deletions

diff --git a/drivers/media/video/mx3_camera.c b/drivers/media/video/mx3_camera.c
index 24c2fe0714c5..f96f92f00f92 100644
--- a/drivers/media/video/mx3_camera.c
+++ b/drivers/media/video/mx3_camera.c
@@ -114,6 +114,7 @@ struct mx3_camera_dev {
         struct list_head        capture;
         spinlock_t              lock;           /* Protects video buffer lists */
         struct mx3_camera_buffer *active;
+        size_t                  buf_total;
         struct vb2_alloc_ctx    *alloc_ctx;
         enum v4l2_field         field;
         int                     sequence;
@@ -198,73 +199,46 @@ static int mx3_videobuf_setup(struct vb2_queue *vq,
         struct soc_camera_device *icd = soc_camera_from_vb2q(vq);
         struct soc_camera_host *ici = to_soc_camera_host(icd->parent);
         struct mx3_camera_dev *mx3_cam = ici->priv;
-        int bytes_per_line = soc_mbus_bytes_per_line(icd->user_width,
-                                                icd->current_fmt->host_fmt);
-
-        if (bytes_per_line < 0)
-                return bytes_per_line;
+        int bytes_per_line;
+        unsigned int height;
 
         if (!mx3_cam->idmac_channel[0])
                 return -EINVAL;
 
-        *num_planes = 1;
-
-        mx3_cam->sequence = 0;
-        sizes[0] = bytes_per_line * icd->user_height;
-        alloc_ctxs[0] = mx3_cam->alloc_ctx;
-
-        if (!*count)
-                *count = 32;
-
-        if (sizes[0] * *count > MAX_VIDEO_MEM * 1024 * 1024)
-                *count = MAX_VIDEO_MEM * 1024 * 1024 / sizes[0];
-
-        return 0;
-}
-
-static int mx3_videobuf_prepare(struct vb2_buffer *vb)
-{
-        struct soc_camera_device *icd = soc_camera_from_vb2q(vb->vb2_queue);
-        struct soc_camera_host *ici = to_soc_camera_host(icd->parent);
-        struct mx3_camera_dev *mx3_cam = ici->priv;
-        struct idmac_channel *ichan = mx3_cam->idmac_channel[0];
-        struct scatterlist *sg;
-        struct mx3_camera_buffer *buf;
-        size_t new_size;
-        int bytes_per_line = soc_mbus_bytes_per_line(icd->user_width,
+        if (fmt) {
+                const struct soc_camera_format_xlate *xlate = soc_camera_xlate_by_fourcc(icd,
+                                                                fmt->fmt.pix.pixelformat);
+                if (!xlate)
+                        return -EINVAL;
+                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;
 
-        buf = to_mx3_vb(vb);
-        sg = &buf->sg;
-
-        new_size = bytes_per_line * icd->user_height;
-
-        if (vb2_plane_size(vb, 0) < new_size) {
-                dev_err(icd->parent, "Buffer too small (%lu < %zu)\n",
-                        vb2_plane_size(vb, 0), new_size);
-                return -ENOBUFS;
-        }
+        sizes[0] = bytes_per_line * height;
 
-        if (buf->state == CSI_BUF_NEEDS_INIT) {
-                sg_dma_address(sg)      = vb2_dma_contig_plane_dma_addr(vb, 0);
-                sg_dma_len(sg)          = new_size;
+        alloc_ctxs[0] = mx3_cam->alloc_ctx;
 
-                buf->txd = ichan->dma_chan.device->device_prep_slave_sg(
-                        &ichan->dma_chan, sg, 1, DMA_FROM_DEVICE,
-                        DMA_PREP_INTERRUPT);
-                if (!buf->txd)
-                        return -EIO;
+        if (!vq->num_buffers)
+                mx3_cam->sequence = 0;
 
-                buf->txd->callback_param        = buf->txd;
-                buf->txd->callback              = mx3_cam_dma_done;
+        if (!*count)
+                *count = 2;
 
-                buf->state = CSI_BUF_PREPARED;
-        }
+        /* If *num_planes != 0, we have already verified *count. */
+        if (!*num_planes &&
+            sizes[0] * *count + mx3_cam->buf_total > MAX_VIDEO_MEM * 1024 * 1024)
+                *count = (MAX_VIDEO_MEM * 1024 * 1024 - mx3_cam->buf_total) /
+                        sizes[0];
 
-        vb2_set_plane_payload(vb, 0, new_size);
+        *num_planes = 1;
 
         return 0;
 }
@@ -288,28 +262,58 @@ static void mx3_videobuf_queue(struct vb2_buffer *vb)
         struct soc_camera_host *ici = to_soc_camera_host(icd->parent);
         struct mx3_camera_dev *mx3_cam = ici->priv;
         struct mx3_camera_buffer *buf = to_mx3_vb(vb);
-        struct dma_async_tx_descriptor *txd = buf->txd;
-        struct idmac_channel *ichan = to_idmac_chan(txd->chan);
+        struct scatterlist *sg = &buf->sg;
+        struct dma_async_tx_descriptor *txd;
+        struct idmac_channel *ichan = mx3_cam->idmac_channel[0];
         struct idmac_video_param *video = &ichan->params.video;
-        dma_cookie_t cookie;
-        u32 fourcc = icd->current_fmt->host_fmt->fourcc;
+        const struct soc_mbus_pixelfmt *host_fmt = icd->current_fmt->host_fmt;
+        int bytes_per_line = soc_mbus_bytes_per_line(icd->user_width, host_fmt);
         unsigned long flags;
+        dma_cookie_t cookie;
+        size_t new_size;
+
+        BUG_ON(bytes_per_line <= 0);
+
+        new_size = bytes_per_line * icd->user_height;
+
+        if (vb2_plane_size(vb, 0) < new_size) {
+                dev_err(icd->parent, "Buffer #%d too small (%lu < %zu)\n",
+                        vb->v4l2_buf.index, vb2_plane_size(vb, 0), new_size);
+                goto error;
+        }
+
+        if (buf->state == CSI_BUF_NEEDS_INIT) {
+                sg_dma_address(sg)      = vb2_dma_contig_plane_dma_addr(vb, 0);
+                sg_dma_len(sg)          = new_size;
+
+                txd = ichan->dma_chan.device->device_prep_slave_sg(
+                        &ichan->dma_chan, sg, 1, DMA_FROM_DEVICE,
+                        DMA_PREP_INTERRUPT);
+                if (!txd)
+                        goto error;
+
+                txd->callback_param     = txd;
+                txd->callback           = mx3_cam_dma_done;
+
+                buf->state              = CSI_BUF_PREPARED;
+                buf->txd                = txd;
+        } else {
+                txd = buf->txd;
+        }
+
+        vb2_set_plane_payload(vb, 0, new_size);
 
         /* This is the configuration of one sg-element */
-        video->out_pixel_fmt    = fourcc_to_ipu_pix(fourcc);
+        video->out_pixel_fmt = fourcc_to_ipu_pix(host_fmt->fourcc);
 
         if (video->out_pixel_fmt == IPU_PIX_FMT_GENERIC) {
                 /*
-                 * If the IPU DMA channel is configured to transport
-                 * generic 8-bit data, we have to set up correctly the
-                 * geometry parameters upon the current pixel format.
-                 * So, since the DMA horizontal parameters are expressed
-                 * in bytes not pixels, convert these in the right unit.
+                 * If the IPU DMA channel is configured to transfer generic
+                 * 8-bit data, we have to set up the geometry parameters
+                 * correctly, according to the current pixel format. The DMA
+                 * horizontal parameters in this case are expressed in bytes,
+                 * not in pixels.
                  */
-                int bytes_per_line = soc_mbus_bytes_per_line(icd->user_width,
-                                                icd->current_fmt->host_fmt);
-                BUG_ON(bytes_per_line <= 0);
-
                 video->out_width        = bytes_per_line;
                 video->out_height       = icd->user_height;
                 video->out_stride       = bytes_per_line;
@@ -353,6 +357,7 @@ static void mx3_videobuf_queue(struct vb2_buffer *vb)
                 mx3_cam->active = NULL;
 
         spin_unlock_irqrestore(&mx3_cam->lock, flags);
+error:
         vb2_buffer_done(vb, VB2_BUF_STATE_ERROR);
 }
 
@@ -386,17 +391,24 @@ static void mx3_videobuf_release(struct vb2_buffer *vb)
         }
 
         spin_unlock_irqrestore(&mx3_cam->lock, flags);
+
+        mx3_cam->buf_total -= vb2_plane_size(vb, 0);
 }
 
 static int mx3_videobuf_init(struct vb2_buffer *vb)
 {
+        struct soc_camera_device *icd = soc_camera_from_vb2q(vb->vb2_queue);
+        struct soc_camera_host *ici = to_soc_camera_host(icd->parent);
+        struct mx3_camera_dev *mx3_cam = ici->priv;
         struct mx3_camera_buffer *buf = to_mx3_vb(vb);
+
         /* This is for locking debugging only */
         INIT_LIST_HEAD(&buf->queue);
         sg_init_table(&buf->sg, 1);
 
         buf->state = CSI_BUF_NEEDS_INIT;
-        buf->txd = NULL;
+
+        mx3_cam->buf_total += vb2_plane_size(vb, 0);
 
         return 0;
 }
@@ -407,13 +419,12 @@ static int mx3_stop_streaming(struct vb2_queue *q)
         struct soc_camera_host *ici = to_soc_camera_host(icd->parent);
         struct mx3_camera_dev *mx3_cam = ici->priv;
         struct idmac_channel *ichan = mx3_cam->idmac_channel[0];
-        struct dma_chan *chan;
         struct mx3_camera_buffer *buf, *tmp;
         unsigned long flags;
 
         if (ichan) {
-                chan = &ichan->dma_chan;
-                chan->device->device_control(chan, DMA_TERMINATE_ALL, 0);
+                struct dma_chan *chan = &ichan->dma_chan;
+                chan->device->device_control(chan, DMA_PAUSE, 0);
         }
 
         spin_lock_irqsave(&mx3_cam->lock, flags);
@@ -421,8 +432,8 @@ static int mx3_stop_streaming(struct vb2_queue *q)
         mx3_cam->active = NULL;
 
         list_for_each_entry_safe(buf, tmp, &mx3_cam->capture, queue) {
-                buf->state = CSI_BUF_NEEDS_INIT;
                 list_del_init(&buf->queue);
+                vb2_buffer_done(&buf->vb, VB2_BUF_STATE_ERROR);
         }
 
         spin_unlock_irqrestore(&mx3_cam->lock, flags);
@@ -432,7 +443,6 @@ static int mx3_stop_streaming(struct vb2_queue *q)
 
 static struct vb2_ops mx3_videobuf_ops = {
         .queue_setup    = mx3_videobuf_setup,
-        .buf_prepare    = mx3_videobuf_prepare,
         .buf_queue      = mx3_videobuf_queue,
         .buf_cleanup    = mx3_videobuf_release,
         .buf_init       = mx3_videobuf_init,
@@ -516,6 +526,7 @@ static int mx3_camera_add_device(struct soc_camera_device *icd)
 
         mx3_camera_activate(mx3_cam, icd);
 
+        mx3_cam->buf_total = 0;
         mx3_cam->icd = icd;
 
         dev_info(icd->parent, "MX3 Camera driver attached to camera %d\n",
@@ -1263,8 +1274,6 @@ static int __devexit mx3_camera_remove(struct platform_device *pdev)
 
         dmaengine_put();
 
-        dev_info(&pdev->dev, "i.MX3x Camera driver unloaded\n");
-
         return 0;
 }