gspca: Fix falling back to lower isoc alt
PATCH 1/1 gspca: Fix falling back to lower isoc alt
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 1/1 gspca: Fix falling back to lower isoc alt settings
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.
--- drivers/media/video/gspca/gspca.c | 2 +- 1 files changed, 1 insertions(+), 1 deletions(-)
drivers/media/video/gspca/gspca.c +1 -1
@@ -988,7 +988,7 @@ retry: ret = -EIO ; goto out; } - alt = ep_tb[--alt_idx].alt; + gspca_dev->alt = ep_tb[--alt_idx].alt; } } out:
Signature · 1 line
1.7.7.4
PATCH 1/1 gspca: Fix falling back to lower isoc alt settings
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.
--- drivers/media/video/gspca/gspca.c | 2 +- 1 files changed, 1 insertions(+), 1 deletions(-)
drivers/media/video/gspca/gspca.c +1 -1
@@ -988,7 +988,7 @@ retry: ret = -EIO ; goto out; } - alt = ep_tb[--alt_idx].alt; + gspca_dev->alt = ep_tb[--alt_idx].alt; } } out:
Signature · 6 lines
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