commit 8ec04a491825e08068e92bed0bba7821893b6433 upstream.

The timer expiry routine `jr3_pci_poll_dev()` checks for expiry by
checking whether the absolute value of `jiffies` (stored in local
variable `now`) is greater than the expected expiry time in jiffy units.
This will fail when `jiffies` wraps around.  Also, it seems to make
sense to handle the expiry one jiffy earlier than the current test.  Use
`time_after_eq()` to check for expiry.

Signed-off-by: Ian Abbott <abbotti@mev.co.uk>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

commit 45292be0b3db0b7f8286683b376e2d9f949d11f9 upstream.

For some reason, the driver does not consider allocation of the
subdevice private data to be a fatal error when attaching the COMEDI
device.  It tests the subdevice private data pointer for validity at
certain points, but omits some crucial tests.  In particular,
`jr3_pci_auto_attach()` calls `jr3_pci_alloc_spriv()` to allocate and
initialize the subdevice private data, but the same function
subsequently dereferences the pointer to access the `next_time_min` and
`next_time_max` members without checking it first.  The other missing
test is in the timer expiry routine `jr3_pci_poll_dev()`, but it will
crash before it gets that far.

Fix the bug by returning `-ENOMEM` from `jr3_pci_auto_attach()` as soon
as one of the calls to `jr3_pci_alloc_spriv()` returns `NULL`.  The
COMEDI core will subsequently call `jr3_pci_detach()` to clean up.

Signed-off-by: Ian Abbott <abbotti@mev.co.uk>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

commit f6b1160eb27f990cc1c48b67a5f83cb63115284e upstream.

Arnd Bergmann pointed out that gcc-6 warns about passing negative signed
integer into swab16() due to the macro expansion of 'outw'.

It appears that the register map constants are causing the warnings.
Actually, it might just be the (1 << 15) ones...

Convert all the constants as suggested by checkpatch.pl:
CHECK: Prefer using the BIT macro

The BIT() macro will make all the constants explicitly 'unsigned', which
helps to avoid the warning.

Fix the, unsused, DT2821_CHANCSR_PRESLA() macro. The "Present List
Address" (PRESLA) bits in the CHANCSR register are read only. This
define was meant to extract the bits from the read value.

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

commit 857a661020a2de3a0304edf33ad656abee100891 upstream.

Commit 0557344e2149 ("staging: comedi: ni_mio_common: fix local var for
32-bit read") changed the type of local variable `d` from `unsigned
short` to `unsigned int` to fix a bug introduced in
commit 9c340ac934db ("staging: comedi: ni_stc.h: add read/write
callbacks to struct ni_private") when reading AI data for NI PCI-6110
and PCI-6111 cards.  Unfortunately, other parts of the function rely on
the variable being `unsigned short` when an offset value in local
variable `signbits` is added to `d` before writing the value to the
`data` array:

			d += signbits;
		  	data[n] = d;

The `signbits` variable will be non-zero in bipolar mode, and is used to
convert the hardware's 2's complement, 16-bit numbers to Comedi's
straight binary sample format (with 0 representing the most negative
voltage).  This breaks because `d` is now 32 bits wide instead of 16
bits wide, so after the addition of `signbits`, `data[n]` ends up being
set to values above 65536 for negative voltages.  This affects all
supported "E series" cards except PCI-6143 (and PXI-6143). Fix it by
ANDing the value written to the `data[n]` with the mask 0xffff.

Fixes: 0557344e2149 ("staging: comedi: ni_mio_common: fix local var for 32-bit read")
Signed-off-by: Ian Abbott <abbotti@mev.co.uk>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

commit 655c4d442d1213b617926cc6d54e2a9a793fb46b upstream.

For NI M Series cards, the Comedi `insn_read` handler for the AI
subdevice is broken due to ANDing the value read from the AI FIFO data
register with an incorrect mask.  The incorrect mask clears all but the
most significant bit of the sample data.  It should preserve all the
sample data bits.  Correct it.

Fixes: 817144ae7fda ("staging: comedi: ni_mio_common: remove unnecessary use of 'board->adbits'")
Signed-off-by: Ian Abbott <abbotti@mev.co.uk>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

commit 5ca05345c56cb979e1a25ab6146437002f95cac8 upstream.

For counter subdevices, the `s->insn_write` handler is being set to the
wrong function, `ni_tio_insn_read()`.  It should be
`ni_tio_insn_write()`.

Signed-off-by: Ian Abbott <abbotti@mev.co.uk>
Reported-by: Éric Piel <piel@delmic.com>
Fixes: 10f74377eec3 ("staging: comedi: ni_tio: make ni_tio_winsn() a
  proper comedi (*insn_write)"
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

commit f0f4b0cc3a8cffd983f5940d46cd0227f3f5710a upstream.

Commit ebb657babfa9 ("staging: comedi: ni_mio_common: clarify the
cmd->start_arg validation and use") introduced a backwards compatibility
issue in the use of asynchronous commands on the AO subdevice when
`start_src` is `TRIG_EXT`.  Valid values for `start_src` are `TRIG_INT`
(for internal, software trigger), and `TRIG_EXT` (for external trigger).
When set to `TRIG_EXT`.  In both cases, the driver relies on an
internal, software trigger to set things up (allowing the user
application to write sufficient samples to the data buffer before the
trigger), so it acts as a software "pre-trigger" in the `TRIG_EXT` case.
The software trigger is handled by `ni_ao_inttrig()`.

Prior to the above change, when `start_src` was `TRIG_INT`, `start_arg`
was required to be 0, and `ni_ao_inttrig()` checked that the software
trigger number was also 0.  After the above change, when `start_src` was
`TRIG_INT`, any value was allowed for `start_arg`, and `ni_ao_inttrig()`
checked that the software trigger number matched this `start_arg` value.
The backwards compatibility issue is that the internal trigger number
now has to match `start_arg` when `start_src` is `TRIG_EXT` when it
previously had to be 0.

Fix the backwards compatibility issue in `ni_ao_inttrig()` by always
allowing software trigger number 0 when `start_src` is something other
than `TRIG_INT`.

Thanks to Spencer Olson for reporting the issue.

Signed-off-by: Ian Abbott <abbotti@mev.co.uk>
Reported-by: Spencer Olson <olsonse@umich.edu>
Fixes: ebb657babfa9 ("staging: comedi: ni_mio_common: clarify the cmd->start_arg validation and use")
Reviewed-by: H Hartley Sweeten <hsweeten@visionengravers.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

commit 403fe7f34e3327ddac2e06a15e76a293d613381e upstream.

Commit 73e0e4dfed4c ("staging: comedi: comedi_test: fix timer lock-up")
fixed a lock-up in the timer routine `waveform_ai_timer()` (which was
called `waveform_ai_interrupt()` at the time) caused by
commit 240512474424 ("staging: comedi: comedi_test: use
comedi_handle_events()").  However, it introduced a race condition that
can result in the timer routine misbehaving, such as accessing freed
memory or dereferencing a NULL pointer.

73e0... changed the timer routine to do nothing unless a
`WAVEFORM_AI_RUNNING` flag was set, and changed `waveform_ai_cancel()`
to clear the flag and replace a call to `del_timer_sync()` with a call
to `del_timer()`.  `waveform_ai_cancel()` may be called from the timer
routine itself (via `comedi_handle_events()`), or from `do_cancel()`.
(`do_cancel()` is called as a result of a file operation (usually a
`COMEDI_CANCEL` ioctl command, or a release), or during device removal.)
When called from `do_cancel()`, the call to `waveform_ai_cancel()` is
followed by a call to `do_become_nonbusy()`, which frees up stuff for
the current asynchronous command under the assumption that it is now
safe to do so.  The race condition occurs when the timer routine
`waveform_ai_timer()` checks the `WAVEFORM_AI_RUNNING` flag just before
it is cleared by `waveform_ai_cancel()`, and is still running during the
call to `do_become_nonbusy()`.  In particular, it can lead to a NULL
pointer dereference:

BUG: unable to handle kernel NULL pointer dereference at (null)
IP: [<ffffffffc0c63add>] waveform_ai_timer+0x17d/0x290 [comedi_test]

That corresponds to this line in `waveform_ai_timer()`:

		unsigned int chanspec = cmd->chanlist[async->cur_chan];

but `do_become_nonbusy()` frees `cmd->chanlist` and sets it to `NULL`.

Fix the race by calling `del_timer_sync()` instead of `del_timer()` in
`waveform_ai_cancel()` when not in an interrupt context.  The only time
`waveform_ai_cancel()` is called in an interrupt context is when it is
called from the timer routine itself, via `comedi_handle_events()`.

There is no longer any need for the `WAVEFORM_AI_RUNNING` flag, so get
rid of it.

The bug was copied from the AI subdevice to the AO when support for
commands on the AO subdevice was added by commit 0cf55bbef2f9 ("staging:
comedi: comedi_test: implement commands on AO subdevice").  That
involves the timer routine `waveform_ao_timer()`, the comedi "cancel"
routine `waveform_ao_cancel()`, and the flag `WAVEFORM_AO_RUNNING`.  Fix
it in the same way as for the AI subdevice.

Fixes: 73e0e4dfed4c ("staging: comedi: comedi_test: fix timer lock-up")
Fixes: 0cf55bbef2f9 ("staging: comedi: comedi_test: implement commands
 on AO subdevice")
Reported-by: Éric Piel <piel@delmic.com>
Signed-off-by: Ian Abbott <abbotti@mev.co.uk>
Cc: Éric Piel <piel@delmic.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

commit 80e162ee9b31d77d851b10f8c5299132be1e120f upstream.

`daqboard2000_find_boardinfo()` is supposed to check if the
DaqBoard/2000 series model is supported, based on the PCI subvendor and
subdevice ID.  The current code is wrong as it is comparing the PCI
device's subdevice ID to an expected, fixed value for the subvendor ID.
It should be comparing the PCI device's subvendor ID to this fixed
value.  Correct it.

Fixes: 7e8401b23e7f ("staging: comedi: daqboard2000: add back subsystem_device check")
Signed-off-by: Ian Abbott <abbotti@mev.co.uk>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

commit d375278d666760e195693b57415ba0a125cadd55 upstream.

DMA is optional with this driver. If it was not enabled the devpriv->dma
pointer will be NULL.

Fix the possible NULL pointer dereference when trying to disable the DMA
channels in das1800_ai_cancel() and tidy up the comments to fix the
checkpatch.pl issues:
WARNING: line over 80 characters

It's probably harmless in das1800_ai_setup_dma() because the 'desc' pointer
will not be used if DMA is disabled but fix it there also.

Fixes: 99dfc3357e98 ("staging: comedi: das1800: remove depends on ISA_DMA_API limitation")
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>