diff options
| author | H Hartley Sweeten <hsweeten@visionengravers.com> | 2013-06-05 22:36:24 (GMT) |
|---|---|---|
| committer | Greg Kroah-Hartman <gregkh@linuxfoundation.org> | 2013-06-06 19:01:34 (GMT) |
| commit | bcc01b4d852c73dbd4cc569c905b5ab1833d00d3 (patch) | |
| tree | 45ec2dd84f114709b6170aa37c2b68f469bbb2c6 | |
| parent | 2a09cba62e82eb8b6202d4ff6dd37ac64a8d624c (diff) | |
| download | linux-fsl-qoriq-bcc01b4d852c73dbd4cc569c905b5ab1833d00d3.tar.xz | |
staging: comedi: pcmad: return errno if AI conversion times out
Instead of returning invalid data, return -ETIME if the analog input
conversion times out.
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>
| -rw-r--r-- | drivers/staging/comedi/drivers/pcmad.c | 22 |
1 files changed, 17 insertions, 5 deletions
diff --git a/drivers/staging/comedi/drivers/pcmad.c b/drivers/staging/comedi/drivers/pcmad.c index 79cc2e6..f64e75b 100644 --- a/drivers/staging/comedi/drivers/pcmad.c +++ b/drivers/staging/comedi/drivers/pcmad.c @@ -72,25 +72,37 @@ struct pcmad_priv_struct { #define TIMEOUT 100 +static int pcmad_ai_wait_for_eoc(struct comedi_device *dev, + int timeout) +{ + int i; + + for (i = 0; i < timeout; i++) { + if ((inb(dev->iobase + PCMAD_STATUS) & 0x3) == 0x3) + return 0; + } + return -ETIME; +} + static int pcmad_ai_insn_read(struct comedi_device *dev, struct comedi_subdevice *s, struct comedi_insn *insn, unsigned int *data) { const struct pcmad_board_struct *board = comedi_board(dev); struct pcmad_priv_struct *devpriv = dev->private; - int i; int chan; int n; + int ret; chan = CR_CHAN(insn->chanspec); for (n = 0; n < insn->n; n++) { outb(chan, dev->iobase + PCMAD_CONVERT); - for (i = 0; i < TIMEOUT; i++) { - if ((inb(dev->iobase + PCMAD_STATUS) & 0x3) == 0x3) - break; - } + ret = pcmad_ai_wait_for_eoc(dev, TIMEOUT); + if (ret) + return ret; + data[n] = inb(dev->iobase + PCMAD_LSB); data[n] |= (inb(dev->iobase + PCMAD_MSB) << 8); |