gspca_sq930x: Creative WebCam Live! Pro recognized, kinda initialised but unusable

Hello again

I've just compiled a new 3.9.7 kernel and applied a patch suggested by hverkuil on #v4l : I removed the comments around reg_w(gspca_dev, SQ930_CTRL_RESET, 0x0000); in ./drivers/media/usb/gspca/sq930x.c at line 839 This is what I get now :

Jun 21 18:19:31 elnath kernel: [    6.587245] gspca_sq930x: reg_w 001e 0000 failed -110

Log extract : http://pastebin.com/ay74d5YB

If reg_r() and reg_w fail, it means that usb_control_msg() returns those -32 and -110. How do I debug that ?

=^.^=