The following usb bandwidth allocation changes were made to the ibm netcam
pro code:
- Don't restart negotiation at max packet size on stop0, as that gets called
by gspca_main during negotiation. Move this to sd_isoc_init.
- Don't ask for full bandwidth when running at 160x120, that does not need
full bandwidth
- Make minimum acceptable bandwidth depend upon resolution
Signed-off-by: Hans de Goede <hdegoede@xxxxxxxxxx>
---
drivers/media/video/gspca/xirlink_cit.c | 41 +++++++++++++++++++++++-------
1 files changed, 31 insertions(+), 10 deletions(-)
diff --git a/drivers/media/video/gspca/xirlink_cit.c b/drivers/media/video/gspca/xirlink_cit.c
index 8715577..f0f6279 100644
--- a/drivers/media/video/gspca/xirlink_cit.c
+++ b/drivers/media/video/gspca/xirlink_cit.c
@@ -2769,16 +2769,43 @@ static int sd_start(struct gspca_dev *gspca_dev)
return 0;
}
+static int sd_isoc_init(struct gspca_dev *gspca_dev)
+{
+ struct usb_host_interface *alt;
+ int max_packet_size;
+
+ switch (gspca_dev->width) {
+ case 160: max_packet_size = 450; break;
+ case 176: max_packet_size = 600; break;
+ default: max_packet_size = 1022; break;
+ }
+
+ /* Start isoc bandwidth "negotiation" at max isoc bandwidth */
+ alt = &gspca_dev->dev->config->intf_cache[0]->altsetting[1];
+ alt->endpoint[0].desc.wMaxPacketSize = cpu_to_le16(max_packet_size);
+
+ return 0;
+}
+
static int sd_isoc_nego(struct gspca_dev *gspca_dev)
{
- int ret, packet_size;
+ int ret, packet_size, min_packet_size;
struct usb_host_interface *alt;
+ switch (gspca_dev->width) {
+ case 160: min_packet_size = 200; break;
+ case 176: min_packet_size = 266; break;
+ default: min_packet_size = 400; break;
+ }
+
alt = &gspca_dev->dev->config->intf_cache[0]->altsetting[1];
packet_size = le16_to_cpu(alt->endpoint[0].desc.wMaxPacketSize);
- packet_size -= 100;
- if (packet_size < 300)
+ if (packet_size <= min_packet_size)
return -EIO;
+
+ packet_size -= 100;
+ if (packet_size < min_packet_size)
+ packet_size = min_packet_size;
alt->endpoint[0].desc.wMaxPacketSize = cpu_to_le16(packet_size);
ret = usb_set_interface(gspca_dev->dev, gspca_dev->iface, 1);
@@ -2796,15 +2823,12 @@ static void sd_stopN(struct gspca_dev *gspca_dev)
static void sd_stop0(struct gspca_dev *gspca_dev)
{
struct sd *sd = (struct sd *) gspca_dev;
- struct usb_host_interface *alt;
/* We cannot use gspca_dev->present here as that is not set when
sd_init gets called and we get called from sd_init */
if (!gspca_dev->dev)
return;
- alt = &gspca_dev->dev->config->intf_cache[0]->altsetting[1];
-
switch (sd->model) {
case CIT_MODEL0:
/* HDG windows does this, but it causes the cams autogain to
@@ -2859,10 +2883,6 @@ static void sd_stop0(struct gspca_dev *gspca_dev)
restarting the stream after this */
/* cit_write_reg(gspca_dev, 0x0000, 0x0112); */
cit_write_reg(gspca_dev, 0x00c0, 0x0100);
-
- /* Start isoc bandwidth "negotiation" at max isoc bandwith
- next stream start */
- alt->endpoint[0].desc.wMaxPacketSize = cpu_to_le16(1022);
break;
}
}
@@ -3179,6 +3199,7 @@ static const struct sd_desc sd_desc_isoc_nego = {
.config = sd_config,
.init = sd_init,
.start = sd_start,
+ .isoc_init = sd_isoc_init,
.isoc_nego = sd_isoc_nego,
.stopN = sd_stopN,
.stop0 = sd_stop0,
--
1.7.3.1
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