Hi Laurent, I can't find where the locking is handled for ISP subdev standard ioctls like ccdc_v4l2_pad_ops.set_fmt(). Using the CCDC as an example, it looks to me like the following sequence happens when e.g. format is set on CCDC pad 0: 1. # media-ctl --set-format '"OMAP3 ISP CCDC":0 [Y8 640x480]' 2. v4l2-dev.c:v4l2_ioctl() this calls vdev->fops->unlocked_ioctl, which was set to v4l2-subdev.c:subdev_ioctl() in "v4l2_subdev_fops" in v4l2-device.c:v4l2_device_register_subdev_nodes() 3. v4l2-subdev.c:subdev_ioctl() 4. video_usercopy() 5. v4l2-ioctl.c:__video_usercopy() 6. v4l2-subdev.c:subdev_do_ioctl() 7. ispccdc.c:ccdc_set_format() ccdc_set_format() sets ccdc->formats[pad], access to which should be serialized, but I don't see how this happens. In the call sequence above, the only opportunity I see is in (2), but only then if ccdc->subdev.devnode.lock is set, which doesn't seem to be done. Can you clarify this for me? What mutex is held during a call to ccdc_set_format()? -Michael MATRIX VISION GmbH, Talstrasse 16, DE-71570 Oppenweiler Registergericht: Amtsgericht Stuttgart, HRB 271090 Geschaeftsfuehrer: Gerhard Thullner, Werner Armingeon, Uwe Furtner -- To unsubscribe from this list: send the line "unsubscribe linux-media" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
