diff options
Diffstat (limited to 'drivers/comedi/drivers/pcmad.c')
| -rw-r--r-- | drivers/comedi/drivers/pcmad.c | 149 |
1 files changed, 149 insertions, 0 deletions
diff --git a/drivers/comedi/drivers/pcmad.c b/drivers/comedi/drivers/pcmad.c new file mode 100644 index 000000000..976eda438 --- /dev/null +++ b/drivers/comedi/drivers/pcmad.c @@ -0,0 +1,149 @@ +// SPDX-License-Identifier: GPL-2.0+ +/* + * 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> + */ + +/* + * Driver: pcmad + * Description: Winsystems PCM-A/D12, PCM-A/D16 + * Devices: [Winsystems] PCM-A/D12 (pcmad12), PCM-A/D16 (pcmad16) + * Author: ds + * 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] - IRQ (unused) + * [2] - Analog input reference (must match jumpers) + * 0 = single-ended (16 channels) + * 1 = differential (8 channels) + * [3] - Analog input encoding (must match jumpers) + * 0 = straight binary (0-5V input range) + * 1 = two's complement (+-10V input range) + */ + +#include <linux/module.h> +#include <linux/comedi/comedidev.h> + +#define PCMAD_STATUS 0 +#define PCMAD_LSB 1 +#define PCMAD_MSB 2 +#define PCMAD_CONVERT 1 + +struct pcmad_board_struct { + const char *name; + unsigned int ai_maxdata; +}; + +static const struct pcmad_board_struct pcmad_boards[] = { + { + .name = "pcmad12", + .ai_maxdata = 0x0fff, + }, { + .name = "pcmad16", + .ai_maxdata = 0xffff, + }, +}; + +static int pcmad_ai_eoc(struct comedi_device *dev, + struct comedi_subdevice *s, + struct comedi_insn *insn, + unsigned long context) +{ + unsigned int status; + + status = inb(dev->iobase + PCMAD_STATUS); + if ((status & 0x3) == 0x3) + return 0; + return -EBUSY; +} + +static int pcmad_ai_insn_read(struct comedi_device *dev, + struct comedi_subdevice *s, + struct comedi_insn *insn, + unsigned int *data) +{ + unsigned int chan = CR_CHAN(insn->chanspec); + unsigned int range = CR_RANGE(insn->chanspec); + unsigned int val; + int ret; + int i; + + for (i = 0; i < insn->n; i++) { + outb(chan, dev->iobase + PCMAD_CONVERT); + + ret = comedi_timeout(dev, s, insn, pcmad_ai_eoc, 0); + if (ret) + return ret; + + val = inb(dev->iobase + PCMAD_LSB) | + (inb(dev->iobase + PCMAD_MSB) << 8); + + /* data is shifted on the pcmad12, fix it */ + if (s->maxdata == 0x0fff) + val >>= 4; + + if (comedi_range_is_bipolar(s, range)) { + /* munge the two's complement value */ + val ^= ((s->maxdata + 1) >> 1); + } + + data[i] = val; + } + + return insn->n; +} + +static int pcmad_attach(struct comedi_device *dev, struct comedi_devconfig *it) +{ + const struct pcmad_board_struct *board = dev->board_ptr; + struct comedi_subdevice *s; + int ret; + + ret = comedi_request_region(dev, it->options[0], 0x04); + if (ret) + return ret; + + ret = comedi_alloc_subdevices(dev, 1); + if (ret) + return ret; + + s = &dev->subdevices[0]; + s->type = COMEDI_SUBD_AI; + if (it->options[1]) { + /* 8 differential channels */ + s->subdev_flags = SDF_READABLE | AREF_DIFF; + s->n_chan = 8; + } else { + /* 16 single-ended channels */ + s->subdev_flags = SDF_READABLE | AREF_GROUND; + s->n_chan = 16; + } + s->len_chanlist = 1; + s->maxdata = board->ai_maxdata; + s->range_table = it->options[2] ? &range_bipolar10 : &range_unipolar5; + s->insn_read = pcmad_ai_insn_read; + + return 0; +} + +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 https://www.comedi.org"); +MODULE_DESCRIPTION("Comedi low-level driver"); +MODULE_LICENSE("GPL"); |