linux-stable.git/drivers/staging/comedi, branch v3.19

staging: comedi: change some printk calls to pr_err

2014-12-03T00:54:43+00:00

There are a handful of calls to printk in ni_stc.h without specified log
levels, as well as one in ni_mio_common.c.  This patch converts these
calls to pr_err() instead, so that they are now explicitly log level
ERR.

Signed-off-by: Chase Southwood 
Reviewed-by: Ian Abbott 
Signed-off-by: Greg Kroah-Hartman

staging: comedi: adl_pci9118: eliminate DMA buffer defragmentation step

2014-12-03T00:31:20+00:00

The DMA operations used by the driver may have been set up to acquire
data from unwanted channels in addition to the wanted channels.
Currently, `interrupt_pci9118_ai_dma()` calls `defragment_dma_buffer()`
to move all the wanted data to the start of the DMA buffer and then
calls `comedi_buf_write_samples()` to copy it all to the comedi async
buffer.  Those two functions used to be called from
`move_block_from_dma()` which was absorbed into
`interrupt_pci9118_ai_dma()`.

Reinstate `move_block_from_dma()` but rewrite it to copy data directly
from the wanted fragments of the DMA buffer to the comedi async buffer
without defragmenting the buffer first.

Signed-off-by: Ian Abbott 
Signed-off-by: Greg Kroah-Hartman

staging: comedi: adl_pci9118: try and avoid unnecessary DMA restart

2014-12-03T00:31:20+00:00

`interrupt_pci9118_ai_dma()` is called on interrupt to transfer data
from DMA buffers into the comedi async data buffer.  Currently it always
restarts DMA.  If double buffering, it restarts DMA on the next DMA
buffer before processing the current DMA buffer, otherwise it restarts
DMA on the same DMA buffer after it has been processed.

For single buffering we can avoid restarting the DMA transfer by
checking the async event flags after the current buffer has been
processed, which is easy.

For double buffering, we need to know how many valid samples there are
in the current buffer before it has been processed and determine whether
there is enough to complete the acquisition.  Call new function
`valid_samples_in_act_dma_buf()` to determine the number of valid
samples in the current DMA buffer, and compare that with the result of
`comedi_nsamples_left()` to determine if DMA needs to be restarted.
(`comedi_nsamples_left()` needs an upper bound to clamp to, so use the
number of valid samples in the DMA buffer plus one for our test.)

It is still possible for DMA to be restarted unnecessarily in the double
buffer case if a `COMEDI_CB_OVERFLOW` event occurs while copying to the
comedi async buffer, but it doesn't really matter.  The ongoing DMA
operation will get disabled when the subdevice's `cancel()` handler is
called when the events are handled later in the interrupt service
routine (as it does currently).

Signed-off-by: Ian Abbott 
Signed-off-by: Greg Kroah-Hartman

staging: comedi: adl_pci9118: simplify interrupt_pci9118_ai_dma() a bit

2014-12-03T00:31:20+00:00

Eliminate the `next_dma_buf` variable in `interrupt_pci9118_ai_dma()`.
It holds the next value of `devpriv->dma_actbuf` when double buffering
is used, but we can just set that to the next value directly at the
point where the buffers are switched as the old value is not used
anywhere else.

Signed-off-by: Ian Abbott 
Signed-off-by: Greg Kroah-Hartman

staging: comedi: adv_pci1723: remove comedi_device 'write_subdev' init

2014-11-26T23:40:00+00:00

The comedi_device 'write_subdev' should only be initialized if the subdevice
supports async commands.

Signed-off-by: H Hartley Sweeten 
Reviewed-by: Ian Abbott 
Signed-off-by: Greg Kroah-Hartman

staging: comedi: adv_pci1723: tidy up multi-line comments

2014-11-26T23:40:00+00:00

Tidy up the multi-line comments to follow the CodingStyle.

Signed-off-by: H Hartley Sweeten 
Reviewed-by: Ian Abbott 
Signed-off-by: Greg Kroah-Hartman

staging: comedi: adv_pci1723: update the MODULE_DESCRIPTION

2014-11-26T23:40:00+00:00

Update the MODULE_DESCRIPTION to something more useful than the
generic "Comedi low-level driver".

Signed-off-by: H Hartley Sweeten 
Reviewed-by: Ian Abbott 
Signed-off-by: Greg Kroah-Hartman

staging: comedi: adv_pci1723: remove subdevice 'len_chanlist' initialization

2014-11-26T23:40:00+00:00

The subdevice 'len_chanlist' is only used by subdevices that support async
commands. Remove the unnecessary initializations in this driver.

Signed-off-by: H Hartley Sweeten 
Reviewed-by: Ian Abbott 
Signed-off-by: Greg Kroah-Hartman

staging: comedi: adv_pci1723: tidy up DIO io_bits initialization

2014-11-26T23:40:00+00:00

Tidy up the code that determines the initial io_bits (direction) of the
digital I/O subdevice and remove the magic numbers.

Signed-off-by: H Hartley Sweeten 
Reviewed-by: Ian Abbott 
Signed-off-by: Greg Kroah-Hartman

staging: comedi: adv_pci1723: tidy up pci1723_dio_insn_config()

2014-11-26T23:40:00+00:00

For aesthetics, tidy this function up and use the register defines
to remove the magic numbers.

Signed-off-by: H Hartley Sweeten 
Reviewed-by: Ian Abbott 
Signed-off-by: Greg Kroah-Hartman