V4L/DVB (7671): pxa-camera: fix DMA sg-list coalescing for more than 2 buffers

Currently the pxa-camera driver has a bug, visible when the user requests
more than 2 video buffers. When the third buffer is queued, it is not
appended to the DMA-descriptor list of the second buffer, but is again
appended to the first buffer. Fix it.

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

diff --git a/drivers/media/video/pxa_camera.c b/drivers/media/video/pxa_camera.c
index 1dcfd91..7cc8e9b 100644 (file)
--- a/drivers/media/video/pxa_camera.c
+++ b/drivers/media/video/pxa_camera.c
@@ -102,11 +102,6 @@ struct pxa_buffer {
        enum pxa_camera_active_dma active_dma;
 };
 
-struct pxa_framebuffer_queue {
-       dma_addr_t              sg_last_dma;
-       struct pxa_dma_desc     *sg_last_cpu;
-};
-
 struct pxa_camera_dev {
        struct device           *dev;
        /* PXA27x is only supposed to handle one camera on its Quick Capture
@@ -131,6 +126,7 @@ struct pxa_camera_dev {
        spinlock_t              lock;
 
        struct pxa_buffer       *active;
+       struct pxa_dma_desc     *sg_tail[3];
 };
 
 static const char *pxa_cam_driver_description = "PXA_Camera";
@@ -144,11 +140,14 @@ static int pxa_videobuf_setup(struct videobuf_queue *vq, unsigned int *count,
                              unsigned int *size)
 {
        struct soc_camera_device *icd = vq->priv_data;
+       struct soc_camera_host *ici =
+               to_soc_camera_host(icd->dev.parent);
+       struct pxa_camera_dev *pcdev = ici->priv;
 
        dev_dbg(&icd->dev, "count=%d, size=%d\n", *count, *size);
 
        /* planar capture requires Y, U and V buffers to be page aligned */
-       if (icd->current_fmt->fourcc == V4L2_PIX_FMT_YUV422P) {
+       if (pcdev->channels == 3) {
                *size = PAGE_ALIGN(icd->width * icd->height); /* Y pages */
                *size += PAGE_ALIGN(icd->width * icd->height / 2); /* U pages */
                *size += PAGE_ALIGN(icd->width * icd->height / 2); /* V pages */
@@ -296,7 +295,7 @@ static int pxa_videobuf_prepare(struct videobuf_queue *vq,
                if (ret)
                        goto fail;
 
-               if (buf->fmt->fourcc == V4L2_PIX_FMT_YUV422P) {
+               if (pcdev->channels == 3) {
                        /* FIXME the calculations should be more precise */
                        sglen_y = dma->sglen / 2;
                        sglen_u = sglen_v = dma->sglen / 4 + 1;
@@ -318,7 +317,7 @@ static int pxa_videobuf_prepare(struct videobuf_queue *vq,
                        goto fail;
                }
 
-               if (buf->fmt->fourcc == V4L2_PIX_FMT_YUV422P) {
+               if (pcdev->channels == 3) {
                        /* init DMA for U channel */
                        ret = pxa_init_dma_channel(pcdev, buf, dma, 1, sglen_u,
                                                   sglen_y, 0x30, size_u);
@@ -343,7 +342,7 @@ static int pxa_videobuf_prepare(struct videobuf_queue *vq,
 
        buf->inwork = 0;
        buf->active_dma = DMA_Y;
-       if (buf->fmt->fourcc == V4L2_PIX_FMT_YUV422P)
+       if (pcdev->channels == 3)
                buf->active_dma |= DMA_U | DMA_V;
 
        return 0;
@@ -371,6 +370,7 @@ static void pxa_videobuf_queue(struct videobuf_queue *vq,
        struct pxa_buffer *buf = container_of(vb, struct pxa_buffer, vb);
        struct pxa_buffer *active;
        unsigned long flags;
+       int i;
 
        dev_dbg(&icd->dev, "%s (vb=0x%p) 0x%08lx %d\n", __func__,
                vb, vb->baddr, vb->bsize);
@@ -383,15 +383,11 @@ static void pxa_videobuf_queue(struct videobuf_queue *vq,
 
        if (!active) {
                CIFR |= CIFR_RESET_F;
-               DDADR(pcdev->dma_chans[0]) = buf->dmas[0].sg_dma;
-               DCSR(pcdev->dma_chans[0]) = DCSR_RUN;
-
-               if (buf->fmt->fourcc == V4L2_PIX_FMT_YUV422P) {
-                       DDADR(pcdev->dma_chans[1]) = buf->dmas[1].sg_dma;
-                       DCSR(pcdev->dma_chans[1]) = DCSR_RUN;
 
-                       DDADR(pcdev->dma_chans[2]) = buf->dmas[2].sg_dma;
-                       DCSR(pcdev->dma_chans[2]) = DCSR_RUN;
+               for (i = 0; i < pcdev->channels; i++) {
+                       DDADR(pcdev->dma_chans[i]) = buf->dmas[i].sg_dma;
+                       DCSR(pcdev->dma_chans[i]) = DCSR_RUN;
+                       pcdev->sg_tail[i] = buf->dmas[i].sg_cpu + buf->dmas[i].sglen - 1;
                }
 
                pcdev->active = buf;
@@ -400,7 +396,6 @@ static void pxa_videobuf_queue(struct videobuf_queue *vq,
                struct pxa_cam_dma *buf_dma;
                struct pxa_cam_dma *act_dma;
                int nents;
-               int i;
 
                for (i = 0; i < pcdev->channels; i++) {
                        buf_dma = &buf->dmas[i];
@@ -412,8 +407,8 @@ static void pxa_videobuf_queue(struct videobuf_queue *vq,
 
                        /* Add the descriptors we just initialized to
                           the currently running chain */
-                       act_dma->sg_cpu[act_dma->sglen - 1].ddadr =
-                               buf_dma->sg_dma;
+                       pcdev->sg_tail[i]->ddadr = buf_dma->sg_dma;
+                       pcdev->sg_tail[i] = buf_dma->sg_cpu + buf_dma->sglen - 1;
 
                        /* Setup a dummy descriptor with the DMA engines current
                         * state