1 files changed, 22 insertions, 46 deletions

diff --git a/drivers/media/video/pwc/pwc-if.c b/drivers/media/video/pwc/pwc-if.c
index f3dc89da4c4e..bd1519a4ecb4 100644
--- a/drivers/media/video/pwc/pwc-if.c
+++ b/drivers/media/video/pwc/pwc-if.c
@@ -287,14 +287,13 @@ static int pwc_allocate_buffers(struct pwc_device *pdev)
         /* create frame buffers, and make circular ring */
         for (i = 0; i < default_fbufs; i++) {
                 if (pdev->fbuf[i].data == NULL) {
-                        kbuf = vmalloc(PWC_FRAME_SIZE); /* need vmalloc since frame buffer > 128K */
+                        kbuf = vzalloc(PWC_FRAME_SIZE); /* need vmalloc since frame buffer > 128K */
                         if (kbuf == NULL) {
                                 PWC_ERROR("Failed to allocate frame buffer %d.\n", i);
                                 return -ENOMEM;
                         }
                         PWC_DEBUG_MEMORY("Allocated frame buffer %d at %p.\n", i, kbuf);
                         pdev->fbuf[i].data = kbuf;
-                        memset(kbuf, 0, PWC_FRAME_SIZE);
                 }
         }
 
@@ -899,10 +898,13 @@ int pwc_isoc_init(struct pwc_device *pdev)
         /* link */
         for (i = 0; i < MAX_ISO_BUFS; i++) {
                 ret = usb_submit_urb(pdev->sbuf[i].urb, GFP_KERNEL);
-                if (ret)
+                if (ret) {
                         PWC_ERROR("isoc_init() submit_urb %d failed with error %d\n", i, ret);
-                else
-                        PWC_DEBUG_MEMORY("URB 0x%p submitted.\n", pdev->sbuf[i].urb);
+                        pdev->iso_init = 1;
+                        pwc_isoc_cleanup(pdev);
+                        return ret;
+                }
+                PWC_DEBUG_MEMORY("URB 0x%p submitted.\n", pdev->sbuf[i].urb);
         }
 
         /* All is done... */
@@ -958,7 +960,7 @@ void pwc_isoc_cleanup(struct pwc_device *pdev)
         /* Stop camera, but only if we are sure the camera is still there (unplug
            is signalled by EPIPE)
          */
-        if (pdev->error_status && pdev->error_status != EPIPE) {
+        if (pdev->error_status != EPIPE) {
                 PWC_DEBUG_OPEN("Setting alternate interface 0.\n");
                 usb_set_interface(pdev->udev, 0, 0);
         }
@@ -967,36 +969,6 @@ void pwc_isoc_cleanup(struct pwc_device *pdev)
         PWC_DEBUG_OPEN("<< pwc_isoc_cleanup()\n");
 }
 
-int pwc_try_video_mode(struct pwc_device *pdev, int width, int height, int new_fps, int new_compression, int new_snapshot)
-{
-        int ret, start;
-
-        /* Stop isoc stuff */
-        pwc_isoc_cleanup(pdev);
-        /* Reset parameters */
-        pwc_reset_buffers(pdev);
-        /* Try to set video mode... */
-        start = ret = pwc_set_video_mode(pdev, width, height, new_fps, new_compression, new_snapshot);
-        if (ret) {
-                PWC_DEBUG_FLOW("pwc_set_video_mode attempt 1 failed.\n");
-                /* That failed... restore old mode (we know that worked) */
-                start = pwc_set_video_mode(pdev, pdev->view.x, pdev->view.y, pdev->vframes, pdev->vcompression, pdev->vsnapshot);
-                if (start) {
-                        PWC_DEBUG_FLOW("pwc_set_video_mode attempt 2 failed.\n");
-                }
-        }
-        if (start == 0)
-        {
-                if (pwc_isoc_init(pdev) < 0)
-                {
-                        PWC_WARNING("Failed to restart ISOC transfers in pwc_try_video_mode.\n");
-                        ret = -EAGAIN; /* let's try again, who knows if it works a second time */
-                }
-        }
-        pdev->drop_frames++; /* try to avoid garbage during switch */
-        return ret; /* Return original error code */
-}
-
 /*********
  * sysfs
  *********/
@@ -1176,7 +1148,7 @@ static int pwc_video_open(struct file *file)
         /* Set some defaults */
         pdev->vsnapshot = 0;
 
-        /* Start iso pipe for video; first try the last used video size
+        /* Set video size, first try the last used video size
            (or the default one); if that fails try QCIF/10 or QSIF/10;
            it that fails too, give up.
          */
@@ -1203,15 +1175,6 @@ static int pwc_video_open(struct file *file)
                 return i;
         }
 
-        i = pwc_isoc_init(pdev);
-        if (i) {
-                PWC_DEBUG_OPEN("Failed to init ISOC stuff = %d.\n", i);
-                pwc_isoc_cleanup(pdev);
-                pwc_free_buffers(pdev);
-                mutex_unlock(&pdev->modlock);
-                return i;
-        }
-
         /* Initialize the webcam to sane value */
         pwc_set_brightness(pdev, 0x7fff);
         pwc_set_agc(pdev, 1, 0);
@@ -1326,6 +1289,11 @@ static ssize_t pwc_video_read(struct file *file, char __user *buf,
                 goto err_out;
         }
 
+        /* Start the stream (if not already started) */
+        rv = pwc_isoc_init(pdev);
+        if (rv)
+                goto err_out;
+
         /* In case we're doing partial reads, we don't have to wait for a frame */
         if (pdev->image_read_pos == 0) {
                 /* Do wait queueing according to the (doc)book */
@@ -1395,6 +1363,7 @@ static unsigned int pwc_video_poll(struct file *file, poll_table *wait)
 {
         struct video_device *vdev = file->private_data;
         struct pwc_device *pdev;
+        int ret;
 
         if (vdev == NULL)
                 return -EFAULT;
@@ -1402,6 +1371,13 @@ static unsigned int pwc_video_poll(struct file *file, poll_table *wait)
         if (pdev == NULL)
                 return -EFAULT;
 
+        /* Start the stream (if not already started) */
+        mutex_lock(&pdev->modlock);
+        ret = pwc_isoc_init(pdev);
+        mutex_unlock(&pdev->modlock);
+        if (ret)
+                return ret;
+
         poll_wait(file, &pdev->frameq, wait);
         if (pdev->error_status)
                 return POLLERR;