diff options
Diffstat (limited to 'drivers/staging/comedi/drivers/pcmad.c')
| -rw-r--r-- | drivers/staging/comedi/drivers/pcmad.c | 158 |
1 files changed, 158 insertions, 0 deletions
diff --git a/drivers/staging/comedi/drivers/pcmad.c b/drivers/staging/comedi/drivers/pcmad.c new file mode 100644 index 00000000..b7c932e1 --- /dev/null +++ b/drivers/staging/comedi/drivers/pcmad.c @@ -0,0 +1,158 @@ +/* + comedi/drivers/pcmad.c + Hardware driver for Winsystems PCM-A/D12 and PCM-A/D16 + + COMEDI - Linux Control and Measurement Device Interface + Copyright (C) 2000,2001 David A. Schleef <ds@schleef.org> + + This program is free software; you can redistribute it and/or modify + it under the terms of the GNU General Public License as published by + the Free Software Foundation; either version 2 of the License, or + (at your option) any later version. + + This program is distributed in the hope that it will be useful, + but WITHOUT ANY WARRANTY; without even the implied warranty of + MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the + GNU General Public License for more details. + + You should have received a copy of the GNU General Public License + along with this program; if not, write to the Free Software + Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA. + +*/ +/* +Driver: pcmad +Description: Winsystems PCM-A/D12, PCM-A/D16 +Author: ds +Devices: [Winsystems] PCM-A/D12 (pcmad12), PCM-A/D16 (pcmad16) +Status: untested + +This driver was written on a bet that I couldn't write a driver +in less than 2 hours. I won the bet, but never got paid. =( + +Configuration options: + [0] - I/O port base + [1] - unused + [2] - Analog input reference + 0 = single ended + 1 = differential + [3] - Analog input encoding (must match jumpers) + 0 = straight binary + 1 = two's complement +*/ + +#include <linux/interrupt.h> +#include "../comedidev.h" + +#include <linux/ioport.h> + +#define PCMAD_SIZE 4 + +#define PCMAD_STATUS 0 +#define PCMAD_LSB 1 +#define PCMAD_MSB 2 +#define PCMAD_CONVERT 1 + +struct pcmad_board_struct { + const char *name; + int n_ai_bits; +}; + +struct pcmad_priv_struct { + int differential; + int twos_comp; +}; + +#define TIMEOUT 100 + +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; + + 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; + } + data[n] = inb(dev->iobase + PCMAD_LSB); + data[n] |= (inb(dev->iobase + PCMAD_MSB) << 8); + + if (devpriv->twos_comp) + data[n] ^= (1 << (board->n_ai_bits - 1)); + } + + return n; +} + +/* + * options: + * 0 i/o base + * 1 unused + * 2 0=single ended 1=differential + * 3 0=straight binary 1=two's comp + */ +static int pcmad_attach(struct comedi_device *dev, struct comedi_devconfig *it) +{ + const struct pcmad_board_struct *board = comedi_board(dev); + struct pcmad_priv_struct *devpriv; + struct comedi_subdevice *s; + int ret; + + ret = comedi_request_region(dev, it->options[0], PCMAD_SIZE); + if (ret) + return ret; + + ret = comedi_alloc_subdevices(dev, 1); + if (ret) + return ret; + + devpriv = kzalloc(sizeof(*devpriv), GFP_KERNEL); + if (!devpriv) + return -ENOMEM; + dev->private = devpriv; + + s = &dev->subdevices[0]; + s->type = COMEDI_SUBD_AI; + s->subdev_flags = SDF_READABLE | AREF_GROUND; + s->n_chan = 16; /* XXX */ + s->len_chanlist = 1; + s->insn_read = pcmad_ai_insn_read; + s->maxdata = (1 << board->n_ai_bits) - 1; + s->range_table = &range_unknown; + + return 0; +} + +static const struct pcmad_board_struct pcmad_boards[] = { + { + .name = "pcmad12", + .n_ai_bits = 12, + }, { + .name = "pcmad16", + .n_ai_bits = 16, + }, +}; +static struct comedi_driver pcmad_driver = { + .driver_name = "pcmad", + .module = THIS_MODULE, + .attach = pcmad_attach, + .detach = comedi_legacy_detach, + .board_name = &pcmad_boards[0].name, + .num_names = ARRAY_SIZE(pcmad_boards), + .offset = sizeof(pcmad_boards[0]), +}; +module_comedi_driver(pcmad_driver); + +MODULE_AUTHOR("Comedi http://www.comedi.org"); +MODULE_DESCRIPTION("Comedi low-level driver"); +MODULE_LICENSE("GPL"); |