staging: comedi: drivers: have core hook up default (*insn_read) for readback

Most of the comedi drivers that provide readback for write only subdevices now
use the comedi core comedi_alloc_subdev_readback() helper to allocate the subdevice
'reaback' member instead of using some member in their private data. These drivers
also hook up the (*insn_read) callback to the comedi_readback_insn_read() helper to
provide the readback.

Have the core automatically hook up the (*insn_read) callback after allocating the
memory if the driver has not already hooked it up to a private function.

Signed-off-by: H Hartley Sweeten <hsweeten@visionengravers.com>
Reviewed-by: Ian Abbott <abbotti@mev.co.uk>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

diff --cc drivers/staging/comedi/drivers.c
Simple merge

diff --cc drivers/staging/comedi/drivers/addi_apci_3120.c
Simple merge

diff --cc drivers/staging/comedi/drivers/addi_apci_3501.c
Simple merge

diff --cc drivers/staging/comedi/drivers/addi_apci_3xxx.c
Simple merge

diff --cc drivers/staging/comedi/drivers/adl_pci6208.c
Simple merge

diff --cc drivers/staging/comedi/drivers/adl_pci9111.c
Simple merge

diff --cc drivers/staging/comedi/drivers/adl_pci9118.c
Simple merge

diff --cc drivers/staging/comedi/drivers/aio_aio12_8.c
Simple merge

diff --cc drivers/staging/comedi/drivers/amplc_pci224.c
Simple merge

diff --cc drivers/staging/comedi/drivers/amplc_pci230.c
Simple merge

diff --cc drivers/staging/comedi/drivers/cb_das16_cs.c
Simple merge

diff --cc drivers/staging/comedi/drivers/cb_pcidas.c
Simple merge

diff --cc drivers/staging/comedi/drivers/cb_pcidas64.c
Simple merge

diff --cc drivers/staging/comedi/drivers/cb_pcimdas.c
Simple merge

diff --cc drivers/staging/comedi/drivers/dac02.c
Simple merge

diff --cc drivers/staging/comedi/drivers/daqboard2000.c
Simple merge

diff --cc drivers/staging/comedi/drivers/das08.c
Simple merge

diff --cc drivers/staging/comedi/drivers/das16.c
Simple merge

diff --cc drivers/staging/comedi/drivers/dmm32at.c
Simple merge

diff --cc drivers/staging/comedi/drivers/dt2801.c
Simple merge

diff --cc drivers/staging/comedi/drivers/dt2811.c
Simple merge

diff --cc drivers/staging/comedi/drivers/dt282x.c
Simple merge

diff --cc drivers/staging/comedi/drivers/dt3000.c
Simple merge

diff --cc drivers/staging/comedi/drivers/fl512.c
Simple merge

diff --cc drivers/staging/comedi/drivers/icp_multi.c
Simple merge

diff --cc drivers/staging/comedi/drivers/ii_pci20kc.c
Simple merge

diff --cc drivers/staging/comedi/drivers/me4000.c
Simple merge

diff --cc drivers/staging/comedi/drivers/me_daq.c
Simple merge

diff --cc drivers/staging/comedi/drivers/mf6x4.c
Simple merge

diff --cc drivers/staging/comedi/drivers/multiq3.c
Simple merge

diff --cc drivers/staging/comedi/drivers/ni_670x.c
Simple merge

diff --cc drivers/staging/comedi/drivers/ni_at_ao.c
Simple merge

diff --cc drivers/staging/comedi/drivers/ni_atmio16d.c
Simple merge

diff --cc drivers/staging/comedi/drivers/ni_mio_common.c
Simple merge

diff --cc drivers/staging/comedi/drivers/pcl711.c
Simple merge

diff --cc drivers/staging/comedi/drivers/pcl726.c
Simple merge

diff --cc drivers/staging/comedi/drivers/pcl812.c
Simple merge

diff --cc drivers/staging/comedi/drivers/pcl818.c
Simple merge

diff --cc drivers/staging/comedi/drivers/pcmmio.c
Simple merge

diff --cc drivers/staging/comedi/drivers/quatech_daqp_cs.c
Simple merge

diff --cc drivers/staging/comedi/drivers/rtd520.c
Simple merge

diff --cc drivers/staging/comedi/drivers/rti800.c
Simple merge

diff --cc drivers/staging/comedi/drivers/rti802.c
Simple merge

diff --cc drivers/staging/comedi/drivers/s526.c
Simple merge

diff --cc drivers/staging/comedi/drivers/s626.c
Simple merge