Ian Abbott 15d5193104 staging: comedi: ni_mio_common: fix AO timer off-by-one regression ... As reported by Éric Piel on the Comedi mailing list (see <https://groups.google.com/forum/#!topic/comedi_list/ueZiR7vTLOU/discussion>), the analog output asynchronous commands are running too fast with a period 50 ns shorter than it should be. This affects all boards with AO command support that are supported by the "ni_pcimio", "ni_atmio", and "ni_mio_cs" drivers. This is a regression bug introduced by commit 080e6795cb ("staging: comedi: ni_mio_common: Cleans up/clarifies ni_ao_cmd"), specifically, this line in `ni_ao_cmd_set_update()`: /* following line: N-1 per STC */ ni_stc_writel(dev, trigvar - 1, NISTC_AO_UI_LOADA_REG); The `trigvar` variable value comes from a call to `ni_ns_to_timer()` which converts a timer period in nanoseconds to a hardware divisor value. The function already reduces the divisor by 1 as required by the hardware, so the above line should not reduce it further by 1. Fix it by replacing `trigvar` by `trigvar - 1` in the above line, and remove the misleading comment. Reported-by: Éric Piel <piel@delmic.com> Fixes: 080e6795cb ("staging: comedi: ni_mio_common: Cleans up/clarifies ni_ao_cmd") Cc: Éric Piel <piel@delmic.com> Cc: Spencer E. Olson <olsonse@umich.edu> Cc: <stable@vger.kernel.org> # 4.7+ Signed-off-by: Ian Abbott <abbotti@mev.co.uk> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>		2017-07-16 09:13:53 +02:00
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drivers	staging: comedi: ni_mio_common: fix AO timer off-by-one regression	2017-07-16 09:13:53 +02:00
kcomedilib	Staging: comedi: kcomedilib: Add module_init/exit function	2016-12-06 10:08:01 +01:00
comedi_buf.c	staging: comedi: support vm_access_process for mmap'd buffer	2017-04-25 20:43:42 +02:00
comedi_compat32.c
comedi_compat32.h	staging: comedi: comedi_compat32.h: add identifiers to function parameters	2017-01-03 15:27:55 +01:00
comedi_fops.c	staging: comedi: use centralized error clean-up in comedi_init()	2017-06-24 00:37:07 +08:00
comedi_internal.h	staging: comedi: support vm_access_process for mmap'd buffer	2017-04-25 20:43:42 +02:00
comedi_pci.c
comedi_pci.h	drivers: staging: comedi: fix function prototypes	2017-01-03 15:27:12 +01:00
comedi_pcmcia.c	staging: comedi: comedi_pcmcia.[ch]: add identifiers to function parameters	2017-01-03 15:27:55 +01:00
comedi_pcmcia.h	staging: comedi: comedi_pcmcia.[ch]: add identifiers to function parameters	2017-01-03 15:27:55 +01:00
comedi_usb.c
comedi_usb.h	staging: comedi: comedi_usb.h: add identifiers to function parameters	2017-01-03 15:27:55 +01:00
comedi.h	staging: comedi: make constants slightly more consistent	2016-10-16 10:26:16 +02:00
comedidev.h	Staging: comedi: comedidev.h: Drop old style zero-length array	2017-01-03 15:29:06 +01:00
comedilib.h	staging: comedi: comedilib.h: Coding style warning fix for block comments	2015-12-21 16:01:12 -08:00
drivers.c	Staging: comedi: Align the * in block comments	2016-10-02 17:29:11 +02:00
Kconfig	staging: comedi: labpc: fix isadma dependency	2017-04-08 12:54:09 +02:00
Makefile
proc.c	Staging: comedi: proc: Warn if unable to create proc entry	2017-01-03 15:30:21 +01:00
range.c
TODO	comedi: note a coverity discovered hole that needs fixing	2016-03-05 14:56:55 -08:00