diff options
| author | H Hartley Sweeten <hsweeten@visionengravers.com> | 2013-03-22 09:50:31 -0700 |
|---|---|---|
| committer | Greg Kroah-Hartman <gregkh@linuxfoundation.org> | 2013-03-25 11:42:58 -0700 |
| commit | 810c73c7e7d3892fb508e28ca774d69309c316a2 (patch) | |
| tree | d3885824a0de3c4aead20ddc1a70c5f039ce69e1 | |
| parent | 3c4dfac8f7d2504234d1b7e3108e401a882bb9e1 (diff) | |
staging: comedi: ni_labpc: introduce labpc_ai_wait_for_data()
Introduce a helper function to wait for the a/d conversion to
complete.
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/ni_labpc.c | 41 |
1 files changed, 26 insertions, 15 deletions
diff --git a/drivers/staging/comedi/drivers/ni_labpc.c b/drivers/staging/comedi/drivers/ni_labpc.c index 9e47fc0322f4..ceb6e786cbdd 100644 --- a/drivers/staging/comedi/drivers/ni_labpc.c +++ b/drivers/staging/comedi/drivers/ni_labpc.c @@ -206,6 +206,8 @@ NI manuals: #define INIT_A1_BITS 0x70 #define COUNTER_B_BASE_REG 0x18 +#define LABPC_ADC_TIMEOUT 1000 + enum scan_mode { MODE_SINGLE_CHAN, MODE_SINGLE_CHAN_INTERVAL, @@ -453,6 +455,21 @@ static void labpc_clear_adc_fifo(struct comedi_device *dev) labpc_read_adc_fifo(dev); } +static int labpc_ai_wait_for_data(struct comedi_device *dev, + int timeout) +{ + struct labpc_private *devpriv = dev->private; + int i; + + for (i = 0; i < timeout; i++) { + devpriv->stat1 = devpriv->read_byte(dev->iobase + STATUS1_REG); + if (devpriv->stat1 & DATA_AVAIL_BIT) + return 0; + udelay(1); + } + return -ETIME; +} + static int labpc_ai_insn_read(struct comedi_device *dev, struct comedi_subdevice *s, struct comedi_insn *insn, @@ -462,8 +479,8 @@ static int labpc_ai_insn_read(struct comedi_device *dev, unsigned int chan = CR_CHAN(insn->chanspec); unsigned int range = CR_RANGE(insn->chanspec); unsigned int aref = CR_AREF(insn->chanspec); - int timeout = 1000; - int i, n; + int ret; + int i; /* disable timed conversions, interrupt generation and dma */ labpc_cancel(dev, s); @@ -489,24 +506,18 @@ static int labpc_ai_insn_read(struct comedi_device *dev, labpc_clear_adc_fifo(dev); - for (n = 0; n < insn->n; n++) { + for (i = 0; i < insn->n; i++) { /* trigger conversion */ devpriv->write_byte(0x1, dev->iobase + ADC_CONVERT_REG); - for (i = 0; i < timeout; i++) { - if (devpriv->read_byte(dev->iobase + - STATUS1_REG) & DATA_AVAIL_BIT) - break; - udelay(1); - } - if (i == timeout) { - comedi_error(dev, "timeout"); - return -ETIME; - } - data[n] = labpc_read_adc_fifo(dev); + ret = labpc_ai_wait_for_data(dev, LABPC_ADC_TIMEOUT); + if (ret) + return ret; + + data[i] = labpc_read_adc_fifo(dev); } - return n; + return insn->n; } #ifdef CONFIG_ISA_DMA_API |