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https://github.com/AuxXxilium/linux_dsm_epyc7002.git
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9fae30acde
The UVC spec is a bit vague wrt devices using bulk endpoints, specifically, how to signal to a device to start streaming. For devices using isoc endpoints, the sequence for start streaming is: 1) The host sends PROBE_CONTROL(SET_CUR) PROBE_CONTROL(GET_CUR) 2) Host selects desired config and calls COMMIT_CONTROL(SET_CUR) 3) Host selects an alt interface other then zero - e.g SELECT_ALTERNATE_INTERFACE(1) 4) The device starts streaming However for devices using bulk endpoints, there must be *no* alt interface other than setting zero. From the UVC spec: "A VideoStreaming interface containing a bulk endpoint for streaming shall support only alternate setting zero. Additional alternate settings containing bulk endpoints are not permitted in a device that is compliant with the Video Class specification." So for devices using bulk endpoints, step #3 above is irrelevant, and thus cannot be used as an indication for the device to start streaming. So in practice, such devices start streaming immediately after a COMMIT_CONTROL(SET_CUR). In the uvc resume() handler, an unsolicited commit is sent, which causes devices using bulk endpoints to start streaming unintentionally. This patch modifies resume() handler to send a commit only if streaming needs to be reestablished, i.e if the device was actually streaming before is was suspended. Signed-off-by: Aviv Greenberg <aviv.d.greenberg@intel.com> Signed-off-by: Guennadi Liakhovetski <g.liakhovetski@gmx.de> Signed-off-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com> Signed-off-by: Mauro Carvalho Chehab <mchehab@osg.samsung.com> |
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| airspy | ||
| as102 | ||
| au0828 | ||
| b2c2 | ||
| cpia2 | ||
| cx231xx | ||
| dvb-usb | ||
| dvb-usb-v2 | ||
| em28xx | ||
| go7007 | ||
| gspca | ||
| hackrf | ||
| hdpvr | ||
| msi2500 | ||
| pvrusb2 | ||
| pwc | ||
| s2255 | ||
| siano | ||
| stk1160 | ||
| stkwebcam | ||
| tm6000 | ||
| ttusb-budget | ||
| ttusb-dec | ||
| usbtv | ||
| usbvision | ||
| uvc | ||
| zr364xx | ||
| Kconfig | ||
| Makefile | ||