[PATCH for 3.2 URGENT] gspca: Fix falling back to lower isoc alt

[PATCH for 3.2 URGENT] gspca: Fix falling back to lower isoc alt

[Hans de Goede]

Hi Mauro et all,

I'm afraid my recent work on gscpa has uncovered another regression in
the gspca core. It no longer properly falls back to a lower alt setting
if there is not enough bandwidth for the initially choosen one.

This is a problem when usb1 devices are plugged into a usb2 hub, or into
a sandybridge motherboard (which uses usb2 hubs internally), since the ehci
scheduling code in the kernel does not allow usb1 devices to use full iso
bandwidth (long story). So we must fall back to a lower setting there!

This means that many (iso mode) usb1 devices supported by gscpa won't work
at their highest resolution with such systems. This patch fixes the
falling back to lower alt settings, thereby also fixing these devices no
longer working (reproduced and fix tested with several cams).

Therefor I'm suggesting this fix as a last minute regression fix for 3.2
Mauro, please send this patch on its merry way to Linus, thanks!

Regards,

Hans

[PATCH for 3.2 URGENT] gspca: Fix falling back to lower isoc alt settings

[Hans de Goede]

The current gspca core code has a regression where it no longer properly
falls back to lower alt settings when there is not enough bandwidth.

This causes many iso based usb-1 cameras to not work when plugged
into a usb2 hub or a sandybridge chipset motherboard!

This patch fixes this.

Signed-off-by: Hans de Goede <hdegoede@redhat.com>
---
 drivers/media/video/gspca/gspca.c |    2 +-
 1 files changed, 1 insertions(+), 1 deletions(-)

diff --git a/drivers/media/video/gspca/gspca.c b/drivers/media/video/gspca/gspca.c
index 7fb90ae..c27dc09 100644
--- a/drivers/media/video/gspca/gspca.c
+++ b/drivers/media/video/gspca/gspca.c
@@ -988,7 +988,7 @@ retry:
 				ret = -EIO;
 				goto out;
 			}
-			alt = ep_tb[--alt_idx].alt;
+			gspca_dev->alt = ep_tb[--alt_idx].alt;
 		}
 	}
 out:
-- 
1.7.7.4

[PATCH for 3.2 URGENT] gspca: Fix falling back to lower isoc alt settings

[Mauro Carvalho Chehab]

The current gspca core code has a regression where it no longer properly
falls back to lower alt settings when there is not enough bandwidth.

This causes many iso based usb-1 cameras to not work when plugged
into a usb2 hub or a sandybridge chipset motherboard!

This patch fixes this.

Signed-off-by: Hans de Goede <hdegoede@redhat.com>
Signed-off-by: Mauro Carvalho Chehab <mchehab@redhat.com>
---
 drivers/media/video/gspca/gspca.c |    2 +-
 1 files changed, 1 insertions(+), 1 deletions(-)

diff --git a/drivers/media/video/gspca/gspca.c b/drivers/media/video/gspca/gspca.c
index 7fb90ae..c27dc09 100644
--- a/drivers/media/video/gspca/gspca.c
+++ b/drivers/media/video/gspca/gspca.c
@@ -988,7 +988,7 @@ retry:
 				ret = -EIO;
 				goto out;
 			}
-			alt = ep_tb[--alt_idx].alt;
+			gspca_dev->alt = ep_tb[--alt_idx].alt;
 		}
 	}
 out:
-- 
1.7.7.4

--
To unsubscribe from this list: send the line "unsubscribe linux-media" in
the body of a message to majordomo@vger.kernel.org
More majordomo info at  http://vger.kernel.org/majordomo-info.html