V4L/DVB (9087): gspca: Image transfer by bulk uses altsetting 0 with any buffer size.

- gspca_dev field 'bulk_size' added.
- when only one altsetting usable, do image transfer by bulk.

Signed-off-by: Jean-Francois Moine <moinejf@free.fr>
Signed-off-by: Mauro Carvalho Chehab <mchehab@redhat.com>

1 files changed, 27 insertions, 15 deletions

diff --git a/drivers/media/video/gspca/gspca.c b/drivers/media/video/gspca/gspca.c
index 342a0f39e5d5..02824fc101d5 100644
--- a/drivers/media/video/gspca/gspca.c
+++ b/drivers/media/video/gspca/gspca.c
@@ -461,25 +461,34 @@ static struct usb_host_endpoint *get_ep(struct gspca_dev *gspca_dev)
         intf = usb_ifnum_to_if(gspca_dev->dev, gspca_dev->iface);
         ep = NULL;
         i = gspca_dev->alt;                     /* previous alt setting */
+
+        /* try isoc */
         while (--i > 0) {                       /* alt 0 is unusable */
                 ep = alt_xfer(&intf->altsetting[i],
                                 gspca_dev->cam.epaddr,
-                                gspca_dev->bulk
-                                        ? USB_ENDPOINT_XFER_BULK
-                                        : USB_ENDPOINT_XFER_ISOC);
+                                USB_ENDPOINT_XFER_ISOC);
                 if (ep)
                         break;
         }
+
+        /* if no isoc, try bulk */
         if (ep == NULL) {
-                err("no transfer endpoint found");
-                return NULL;
+                ep = alt_xfer(&intf->altsetting[0],
+                                gspca_dev->cam.epaddr,
+                                USB_ENDPOINT_XFER_BULK);
+                if (ep == NULL) {
+                        err("no transfer endpoint found");
+                        return NULL;
+                }
         }
         PDEBUG(D_STREAM, "use alt %d ep 0x%02x",
                         i, ep->desc.bEndpointAddress);
-        ret = usb_set_interface(gspca_dev->dev, gspca_dev->iface, i);
-        if (ret < 0) {
-                err("set interface err %d", ret);
-                return NULL;
+        if (i > 0) {
+                ret = usb_set_interface(gspca_dev->dev, gspca_dev->iface, i);
+                if (ret < 0) {
+                        err("set interface err %d", ret);
+                        return NULL;
+                }
         }
         gspca_dev->alt = i;             /* memorize the current alt setting */
         return ep;
@@ -497,9 +506,10 @@ static int create_urbs(struct gspca_dev *gspca_dev,
         /* calculate the packet size and the number of packets */
         psize = le16_to_cpu(ep->desc.wMaxPacketSize);
 
-        /* See paragraph 5.9 / table 5-11 of the usb 2.0 spec. */
-        psize = (psize & 0x07ff) * (1 + ((psize >> 11) & 3));
-        if (!gspca_dev->bulk) {
+        if (gspca_dev->alt != 0) {              /* isoc */
+
+                /* See paragraph 5.9 / table 5-11 of the usb 2.0 spec. */
+                psize = (psize & 0x07ff) * (1 + ((psize >> 11) & 3));
                 npkt = ISO_MAX_SIZE / psize;
                 if (npkt > ISO_MAX_PKT)
                         npkt = ISO_MAX_PKT;
@@ -508,9 +518,11 @@ static int create_urbs(struct gspca_dev *gspca_dev,
                         "isoc %d pkts size %d = bsize:%d",
                         npkt, psize, bsize);
                 nurbs = DEF_NURBS;
-        } else {
+        } else {                                /* bulk */
                 npkt = 0;
-                bsize = psize;
+                bsize = gspca_dev->cam. bulk_size;
+                if (bsize == 0)
+                        bsize = psize;
                 PDEBUG(D_STREAM, "bulk bsize:%d", bsize);
                 nurbs = 1;
         }
@@ -595,7 +607,7 @@ static int gspca_init_transfer(struct gspca_dev *gspca_dev)
                 atomic_set(&gspca_dev->nevent, 0);
 
                 /* bulk transfers are started by the subdriver */
-                if (gspca_dev->bulk)
+                if (gspca_dev->alt == 0)
                         break;
 
                 /* submit the URBs */