video1394: add poll file operation support

This patch adds support for the poll file operation to the video1394
driver.

Signed-off-by: David Moore <dcm@acm.org>
Signed-off-by: Stefan Richter <stefanr@s5r6.in-berlin.de>

diff --git a/drivers/ieee1394/video1394.c b/drivers/ieee1394/video1394.c
index 6b5353d81ae267104c26dc6e9bebe6c251c61c7b..af78b840dc26f99bf5ee5a1102891db159fa53cc 100644 (file)
--- a/drivers/ieee1394/video1394.c
+++ b/drivers/ieee1394/video1394.c
@@ -1181,7 +1181,8 @@ static int video1394_mmap(struct file *file, struct vm_area_struct *vma)
 
        lock_kernel();
        if (ctx->current_ctx == NULL) {
-               PRINT(KERN_ERR, ctx->ohci->host->id, "Current iso context not set");
+               PRINT(KERN_ERR, ctx->ohci->host->id,
+                               "Current iso context not set");
        } else
                res = dma_region_mmap(&ctx->current_ctx->dma, file, vma);
        unlock_kernel();
@@ -1189,6 +1190,40 @@ static int video1394_mmap(struct file *file, struct vm_area_struct *vma)
        return res;
 }
 
+static unsigned int video1394_poll(struct file *file, poll_table *pt)
+{
+       struct file_ctx *ctx;
+       unsigned int mask = 0;
+       unsigned long flags;
+       struct dma_iso_ctx *d;
+       int i;
+
+       lock_kernel();
+       ctx = file->private_data;
+       d = ctx->current_ctx;
+       if (d == NULL) {
+               PRINT(KERN_ERR, ctx->ohci->host->id,
+                               "Current iso context not set");
+               mask = POLLERR;
+               goto done;
+       }
+
+       poll_wait(file, &d->waitq, pt);
+
+       spin_lock_irqsave(&d->lock, flags);
+       for (i = 0; i < d->num_desc; i++) {
+               if (d->buffer_status[i] == VIDEO1394_BUFFER_READY) {
+                       mask |= POLLIN | POLLRDNORM;
+                       break;
+               }
+       }
+       spin_unlock_irqrestore(&d->lock, flags);
+done:
+       unlock_kernel();
+
+       return mask;
+}
+
 static int video1394_open(struct inode *inode, struct file *file)
 {
        int i = ieee1394_file_to_instance(file);
@@ -1257,6 +1292,7 @@ static struct file_operations video1394_fops=
 #ifdef CONFIG_COMPAT
        .compat_ioctl = video1394_compat_ioctl,
 #endif
+       .poll =         video1394_poll,
        .mmap =         video1394_mmap,
        .open =         video1394_open,
        .release =      video1394_release