diff options
| author | H Hartley Sweeten <hsweeten@visionengravers.com> | 2015-08-05 10:44:55 -0700 |
|---|---|---|
| committer | Greg Kroah-Hartman <gregkh@linuxfoundation.org> | 2015-08-07 15:03:28 -0700 |
| commit | fb7891e48fc2eac16f615e81df06b7510981ef73 (patch) | |
| tree | 4672e8e49bce71a9bf7fe7f3e75426d678932487 /drivers | |
| parent | 023c129f0a90edf1a9cf2c7ba9086f029f56d488 (diff) | |
staging: comedi: me4000: fix me4000_ai_insn_read()
The coemdi (*insn_read) functions are supposed to read insn->n values
from the hardware. Make this function work like the core expects.
Use the comedi_offset_munge() helper to munge the two's complement
values to offset binary.
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>
Diffstat (limited to 'drivers')
| -rw-r--r-- | drivers/staging/comedi/drivers/me4000.c | 32 |
1 files changed, 14 insertions, 18 deletions
diff --git a/drivers/staging/comedi/drivers/me4000.c b/drivers/staging/comedi/drivers/me4000.c index 4231e393c577..c15e731db6c0 100644 --- a/drivers/staging/comedi/drivers/me4000.c +++ b/drivers/staging/comedi/drivers/me4000.c @@ -456,16 +456,8 @@ static int me4000_ai_insn_read(struct comedi_device *dev, int aref = CR_AREF(insn->chanspec); unsigned int entry = 0; unsigned int tmp; - unsigned int lval; int ret; - - if (insn->n == 0) { - return 0; - } else if (insn->n > 1) { - dev_err(dev->class_dev, "Invalid instruction length %d\n", - insn->n); - return -EINVAL; - } + int i; entry |= ME4000_AI_LIST_RANGE(rang); entry |= chan; @@ -515,18 +507,22 @@ static int me4000_ai_insn_read(struct comedi_device *dev, outl(ME4000_AI_MIN_TICKS, dev->iobase + ME4000_AI_CHAN_TIMER_REG); outl(ME4000_AI_MIN_TICKS, dev->iobase + ME4000_AI_CHAN_PRE_TIMER_REG); - /* Start conversion by dummy read */ - inl(dev->iobase + ME4000_AI_START_REG); + for (i = 0; i < insn->n; i++) { + unsigned int val; - ret = comedi_timeout(dev, s, insn, me4000_ai_eoc, 0); - if (ret) - return ret; + /* start conversion by dummy read */ + inl(dev->iobase + ME4000_AI_START_REG); - /* Read value from data fifo */ - lval = inl(dev->iobase + ME4000_AI_DATA_REG) & 0xFFFF; - data[0] = lval ^ 0x8000; + ret = comedi_timeout(dev, s, insn, me4000_ai_eoc, 0); + if (ret) + return ret; - return 1; + /* read two's complement value and munge to offset binary */ + val = inl(dev->iobase + ME4000_AI_DATA_REG); + data[i] = comedi_offset_munge(s, val); + } + + return insn->n; } static int me4000_ai_cancel(struct comedi_device *dev, |