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The comedi code came into the kernel back in 2008, but traces its
lifetime to much much earlier. It's been polished and buffed and
there's really nothing preventing it from being part of the "real"
portion of the kernel.
So move it to drivers/comedi/ as it belongs there.
Many thanks to the hundreds of developers who did the work to make this
happen.
Cc: Ian Abbott <abbotti@mev.co.uk>
Cc: H Hartley Sweeten <hsweeten@visionengravers.com>
Link: https://lore.kernel.org/r/YHauop4u3sP6lz8j@kroah.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
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The analog input subdevice supports Comedi asynchronous commands that
use Comedi's 16-bit sample format. However, the call to
`comedi_buf_write_samples()` is passing the address of a 32-bit integer
parameter. On bigendian machines, this will copy 2 bytes from the wrong
end of the 32-bit value. Fix it by changing the type of the parameter
holding the sample value to `unsigned short`.
[Note: the bug was introduced in commit edf4537bcbf5 ("staging: comedi:
pcl818: use comedi_buf_write_samples()") but the patch applies better to
commit d615416de615 ("staging: comedi: pcl818: introduce
pcl818_ai_write_sample()").]
Fixes: d615416de615 ("staging: comedi: pcl818: introduce pcl818_ai_write_sample()")
Cc: <stable@vger.kernel.org> # 4.0+
Signed-off-by: Ian Abbott <abbotti@mev.co.uk>
Link: https://lore.kernel.org/r/20210223143055.257402-10-abbotti@mev.co.uk
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
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Rationale:
Reduces attack surface on kernel devs opening the links for MITM
as HTTPS traffic is much harder to manipulate.
Deterministic algorithm:
For each file:
If not .svg:
For each line:
If doesn't contain `\bxmlns\b`:
For each link, `\bhttp://[^# \t\r\n]*(?:\w|/)`:
If neither `\bgnu\.org/license`, nor `\bmozilla\.org/MPL\b`:
If both the HTTP and HTTPS versions
return 200 OK and serve the same content:
Replace HTTP with HTTPS.
Signed-off-by: Alexander A. Klimov <grandmaster@al2klimov.de>
Link: https://lore.kernel.org/r/20200721192750.67925-1-grandmaster@al2klimov.de
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
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Variable segpos is being assigned but is never used hence it is redundant
and can be removed.
Cleans up clang warning:
warning: variable 'segpos' set but not used [-Wunused-but-set-variable]
Signed-off-by: Colin Ian King <colin.king@canonical.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
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It's good to have SPDX identifiers in all files to make it easier to
audit the kernel tree for correct licenses.
Update the drivers/staging/comedi files files with the correct SPDX
license identifier based on the license text in the file itself. The
SPDX identifier is a legally binding shorthand, which can be used
instead of the full boiler plate text.
This work is based on a script and data from Thomas Gleixner, Philippe
Ombredanne, and Kate Stewart.
Cc: Ian Abbott <abbotti@mev.co.uk>
Cc: H Hartley Sweeten <hsweeten@visionengravers.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Kate Stewart <kstewart@linuxfoundation.org>
Cc: Philippe Ombredanne <pombredanne@nexb.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
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Block comments should align the * on each line as reported by checkpatch
Signed-off-by: Jakub Jedelsky <jakub.jedelsky@gmail.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
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These defines are not used. Remove them to get rid of the
checkpatch.pl issue about avoiding CamelCase.
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>
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Fix the checkpatch.pl issues.
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>
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As preparation for removal of "comedi_fc.h", replace calls to the
`cfc_check_trigger_...` functions from "comedi_fc.h" with the
replacement `comedi_check_trigger_...` functions from "../comedidev.h"
and remove the inclusion of "comedi_fc.h".
Signed-off-by: Ian Abbott <abbotti@mev.co.uk>
Reviewed-by: H Hartley Sweeten <hsweeten@visionengravers.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
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This driver uses an 8254 timer to generate the pacer clock used for analog
input data acquisition. Convert it to use the comedi_8254 module to provide
support for the 8254 timer.
Note that the pacer does not have to be stopped when starting a new async
command in pcl818_ai_cmd() or when the card is initialy reset by pcl818_reset().
The counters are all reset when the driver is initially attached and the
counters used by the pacer are stopped when a command is canceled.
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>
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Correct one coding style problem(detected by checkpatch.pl) in pcl818.c.
- line over 80 characters
Signed-off-by: Simon Guo <wei.guo.simon@gmail.com>
Reviewed-by: Ian Abbott <abbotti@mev.co.uk>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
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Correct one coding style problem(detected by checkpatch.pl) in pcl818.c.
- code indent should use tabs where possible
It is fixed by reformatting the comment block to usual comment style.
And with the reformatting, following coding style problem is also fixed:
- please, no space before tabs
Signed-off-by: Simon Guo <wei.guo.simon@gmail.com>
Reviewed-by: Ian Abbott <abbotti@mev.co.uk>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
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This driver can acquire analog input samples during the async command with
DMA, by using the FIFO, or sample-by-sample using the End-Of-Conversion
interrupt. All three methods do the following sequence:
1) check for channel dropout
2) add the sample to the async buffer
3) advance the channel dropout detection and detect the end of the command
Merge this sequence into a new helper 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>
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Hardware errors should be reported with the COMEDI_CB_ERROR event. This event
will cause the async command to cancel. It's not necessary to also set the
COMEDI_CB_EOA event. Remove these events.
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>
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THe pcl818_ai_setup_dma() and pcl818_ai_setup_next_dma() functions are similar
other than the buffer switch and the inclusion of the "unread_samples" in
pcl818_ai_setup_next_dma() when calculating the dma size.
Merge these two functions by initializing the 'dma->cur_dma' in the callers
and passing '0' for the "unread_samples" when first starting the DMA.
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>
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Currently this driver determines the number of DMA "runs" needed and the size
of the "last" DMA transfer in order to perform a command. As long as there are
more "runs" required, the dma->size is set to the buffer maxsize. On the last
"run" the buffer is set to the "last" size.
Refactor the driver to use the comedi core helpers to determine the DMA size
based on the buffer maxsize and the number of samples remaining in the command.
This allows removing the 'dma_runs_to_end' and 'last_dma_run' mamebers from
the private data. Also remove the 'ai_data_len' member which is set but never
used.
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>
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Use the new comedi_isadma module to provide the ISA DMA support. This removes
all the ISA_DMA_API code from this driver and allows the driver to be used on
platforms that don't support the ISA_DMA_API.
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>
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According to Documentation/DMA-ISA-LPC.txt, the DMA lock needs to be
claimed before using any of the ISA DMA routines. Introduce a helper
function to disable the ISA DMA controller and add the necessary
locking calls.
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>
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Introduce a helper function to program the ISA DMA controller. Program
the ISA DMA as described in Documentation/DMA-ISA-LPC.txt.
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>
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Currently this function always transfers the full DMA buffer to the comedi
async buffer. When the cmd->stop_src == TRIG_COUNT the last DMA transfer
might be smaller than the buffer size. This results in invalid data being
added to the asunc buffer.
Add a 'size' member to the DMA descriptor and initialize it with the
actual size of the DMA transfer. Use that in pcl818_handle_dma() to
return the proper number of samples. Use the comedi_bytes_to_samples()
helper to convert the byte size to comedi samples. Remove the unnecessary
'bufptr' local variable.
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>
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Use dma_{alloc,free}_coherent() to allocate and free the DMA buffers.
This removes the dependancy on VIRT_TO_BUS.
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>
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For aesthetics, introduce a struct to hold the DMA descriptor data.
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>
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For aesthetics, move the freeing of the DMA channel and the buffers to
a helper 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>
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DMA is optional with this driver. Introduce a helper function to request
the DMA channel and allocate the buffers. Don't fail the driver attach
if the user passed an invalid DMA channel or the channel cannot be
requested.
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>
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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>
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Remove the private data member 'ai_act_scan' and use the comedi_async
'scans_done' member to detect the end-of-acquisition.
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>
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This member of the private data is set to '0' but never used. Remove it.
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>
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The commedi_async 'cur_chan' member is used to track the current position
in the chanlist for a scan. Currently only a couple comedi drivers use
this member.
For aeshtetics, move the 'cur_chan' tracking into the core for non-SDF_PACKED
subdevices. The 'cur_chan' will be updated after reading or writing samples
to the async buffer by comedi_inc_scan_progress(). All non-SDF_PACKED subdevices
will then automatiaclly track the 'cur_chan'.
Some of the drivers use the 'cur_chan' to detect the end of scan event when
counting scans. The COMEDI_CB_EOS event is automatically added by the core
when the end of scan is detected. The drivers just need to check if the
'cur_chan' is 0 to count the number of scans completed.
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>
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For aesthetics, use comedi_buf_write_samples() to add the sample to the
async buffer.
The core will add the COMEDI_CB_BLOCK event when data is written to the
async buffer. Remove the unnecessary event in the driver.
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>
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This inline function is just a wrapper around comedi_bytes_per_scan().
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>
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cfc_handle_events() is just a wrapper around comedi_handle_events().
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>
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The `comedi_board(dev)` inline function calls just return
`dev->board_ptr`. Expand the inline function calls.
Signed-off-by: Ian Abbott <abbotti@mev.co.uk>
Reviewed-by: H Hartley Sweeten <hsweeten@visionengravers.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
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Use the new comedi_subdevice 'readback' member and the core provided
(*insn_read) for the readback of the analog output subdevice channels.
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>
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The comedi_error() function is just a wrapper around dev_err() that adds
the dev->driver->driver_name prefix to the message and a terminating
new-line character. The addition of the driver_name is just added noise
and some of the users of comedi_error() add unnecessary additional new-line
characters.
Use dev_err() directly instead of comedi_error() to avoid any confusion
and so that all the comedi generated kernel messages have the same format.
Signed-off-by: H Hartley Sweeten <hsweeten@visionengravers.com>
Cc: Ian Abbott <abbotti@mev.co.uk>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
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Use the comedi_fc helper to get the number of bytes per scan.
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>
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Use the comedi_fc helper cfc_check_trigger_arg_is() to validate the
trigger argument when the source is TRIG_TIMER.
The minimum test is not needed, this was already validated in Step 3.
All the arguments are unsigned int, change the local variable to an
unsigned int and rename it for aesthetic reasons.
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>
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Change the parameters of `comedi_buf_put()` to pass a pointer to the
comedi subdevice instead of a pointer to the "async" structure belonging
to the subdevice.
The function puts a sample value in the comedi buffer, but currently
only deals with 16-bit sample types. A future version could deal with
16 or 32-bit sample types depending on the value of the SDF_LSAMPL
subdevice flag.
The main aim at the moment is to replace all the `struct comedi_async *`
parameters with `struct comedi_subdevice *` parameters in the comedi
driver API.
Signed-off-by: Ian Abbott <abbotti@mev.co.uk>
Reviewed-by: H Hartley Sweeten <hsweeten@visionengravers.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
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Use the comedi_fc helper function to automatically call the subdevice
(*cancel) function when needed and call comedi_event().
Update the Kconfig so that COMEDI_PCL818 selects COMEDI_FC.
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>
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Like done in the pcl812 driver, use the boardinfo to determine what
should be reset.
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>
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For aesthetics, rename the timer/counter enable request register
and define its bits.
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>
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Rename this function so it has namespace associated with the driver.
The cmd->scan_begin_src is always TRIG_FOLLOW and the only valid
cmd->convert_src is TRIG_TIMER or TRIG_EXT so pcl818_ai_cmd_mode()
is always called with a 'mode' of 1 or 3. The 'mode' actually indicates
the trigger source.
Absorb pcl818_ai_cmd_mode() into this function and simplify the code.
This also removes the need for a forward declaration.
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>
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Absorb this function into pcl818_ai_cmd_mode() and simplify the code.
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>
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Define the bits in the register to remove the magic values.
Tidy up pcl818_ai_cancel(). The 0x73 mask of the value read from
the control register will disable dma and interrupts but it does
not change the trigger mode. So the software trigger following it
might not work.
Just disable the trigger and clear any pending end-of-conversion.
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>
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Move this function to remove the need for the forward declaration. Rename it
so it has namespace associated with the driver. Remove the unnecessary
comedi_subdevice parameter from the function.
The hardware has per-channel programmable gain. This function first sets the
range for each channel then sets the mux register to automatically scan the
channels.
The use of 'muxonechan' when programming the ranges is incorrect. Only the low
4-bits are supposed to be set when programming the ranges.
Introduce a couple helper functions to set the range for a channel and to set
the first/last channels to scan.
Tidy up the range and mux register defines.
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>
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Define the bits in the status register and remove the magic values.
Writing any value to the status register clears any pending interrupt.
For aesthetics, rename the status register and remove the "clrint"
register.
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>
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For aesthetics, rename the analog input register defines and convert
the offsets to hex.
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>
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Introduce a helper function to start a software triggered analog input
conversion.
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>
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Introduce a helper function to clear the end-of-conversion flag.
This flag is set when an analog input conversion is finished and the
hardware generates an interrupt request. Writing any value to the
register resets the flag and re-enables the interrupt.
Remove the clearing of the flag in pcl818_handle_eoc(). The interrupt
function will handle clearing the flag.
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>
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For aesthetics, move this function out of the async command support
code.
For safety, the INT request (end-of-conversion flag) should be cleared
before doing each conversion and after the final data sample is read.
This driver already clears the flag before starting a conversion but it
does not clear the flag after the final sample.
Refactor the function a bit so that the flag is cleared for a conversion
timeout and after the last sample.
Do a bit of other tidying up during the move.
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>
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For aesthetics, tidy up the analog output subdevice code.
Change the regsiter map defines to simplify the code.
Move the analog subdevice support functions out of the analog input
support functions. Tidy them up a bit during the move.
Reverse the logic of the subdevice init and add some whitespace.
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>
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Greg Kroah-Hartman
Ian Abbott
Alexander A. Klimov
Colin Ian King
Jakub Jedelsky
H Hartley Sweeten
Simon Guo