1 // SPDX-License-Identifier: GPL-2.0+ 2 /* 3 * pcmad.c 4 * Hardware driver for Winsystems PCM-A/D12 and PCM-A/D16 5 * 6 * COMEDI - Linux Control and Measurement Device Interface 7 * Copyright (C) 2000,2001 David A. Schleef <ds@schleef.org> 8 */ 9 10 /* 11 * Driver: pcmad 12 * Description: Winsystems PCM-A/D12, PCM-A/D16 13 * Devices: [Winsystems] PCM-A/D12 (pcmad12), PCM-A/D16 (pcmad16) 14 * Author: ds 15 * Status: untested 16 * 17 * This driver was written on a bet that I couldn't write a driver 18 * in less than 2 hours. I won the bet, but never got paid. =( 19 * 20 * Configuration options: 21 * [0] - I/O port base 22 * [1] - IRQ (unused) 23 * [2] - Analog input reference (must match jumpers) 24 * 0 = single-ended (16 channels) 25 * 1 = differential (8 channels) 26 * [3] - Analog input encoding (must match jumpers) 27 * 0 = straight binary (0-5V input range) 28 * 1 = two's complement (+-10V input range) 29 */ 30 31 #include <linux/module.h> 32 #include <linux/comedi/comedidev.h> 33 34 #define PCMAD_STATUS 0 35 #define PCMAD_LSB 1 36 #define PCMAD_MSB 2 37 #define PCMAD_CONVERT 1 38 39 struct pcmad_board_struct { 40 const char *name; 41 unsigned int ai_maxdata; 42 }; 43 44 static const struct pcmad_board_struct pcmad_boards[] = { 45 { 46 .name = "pcmad12", 47 .ai_maxdata = 0x0fff, 48 }, { 49 .name = "pcmad16", 50 .ai_maxdata = 0xffff, 51 }, 52 }; 53 54 static int pcmad_ai_eoc(struct comedi_device *dev, 55 struct comedi_subdevice *s, 56 struct comedi_insn *insn, 57 unsigned long context) 58 { 59 unsigned int status; 60 61 status = inb(dev->iobase + PCMAD_STATUS); 62 if ((status & 0x3) == 0x3) 63 return 0; 64 return -EBUSY; 65 } 66 67 static int pcmad_ai_insn_read(struct comedi_device *dev, 68 struct comedi_subdevice *s, 69 struct comedi_insn *insn, 70 unsigned int *data) 71 { 72 unsigned int chan = CR_CHAN(insn->chanspec); 73 unsigned int range = CR_RANGE(insn->chanspec); 74 unsigned int val; 75 int ret; 76 int i; 77 78 for (i = 0; i < insn->n; i++) { 79 outb(chan, dev->iobase + PCMAD_CONVERT); 80 81 ret = comedi_timeout(dev, s, insn, pcmad_ai_eoc, 0); 82 if (ret) 83 return ret; 84 85 val = inb(dev->iobase + PCMAD_LSB) | 86 (inb(dev->iobase + PCMAD_MSB) << 8); 87 88 /* data is shifted on the pcmad12, fix it */ 89 if (s->maxdata == 0x0fff) 90 val >>= 4; 91 92 if (comedi_range_is_bipolar(s, range)) { 93 /* munge the two's complement value */ 94 val ^= ((s->maxdata + 1) >> 1); 95 } 96 97 data[i] = val; 98 } 99 100 return insn->n; 101 } 102 103 static int pcmad_attach(struct comedi_device *dev, struct comedi_devconfig *it) 104 { 105 const struct pcmad_board_struct *board = dev->board_ptr; 106 struct comedi_subdevice *s; 107 int ret; 108 109 ret = comedi_request_region(dev, it->options[0], 0x04); 110 if (ret) 111 return ret; 112 113 ret = comedi_alloc_subdevices(dev, 1); 114 if (ret) 115 return ret; 116 117 s = &dev->subdevices[0]; 118 s->type = COMEDI_SUBD_AI; 119 if (it->options[1]) { 120 /* 8 differential channels */ 121 s->subdev_flags = SDF_READABLE | AREF_DIFF; 122 s->n_chan = 8; 123 } else { 124 /* 16 single-ended channels */ 125 s->subdev_flags = SDF_READABLE | AREF_GROUND; 126 s->n_chan = 16; 127 } 128 s->len_chanlist = 1; 129 s->maxdata = board->ai_maxdata; 130 s->range_table = it->options[2] ? &range_bipolar10 : &range_unipolar5; 131 s->insn_read = pcmad_ai_insn_read; 132 133 return 0; 134 } 135 136 static struct comedi_driver pcmad_driver = { 137 .driver_name = "pcmad", 138 .module = THIS_MODULE, 139 .attach = pcmad_attach, 140 .detach = comedi_legacy_detach, 141 .board_name = &pcmad_boards[0].name, 142 .num_names = ARRAY_SIZE(pcmad_boards), 143 .offset = sizeof(pcmad_boards[0]), 144 }; 145 module_comedi_driver(pcmad_driver); 146 147 MODULE_AUTHOR("Comedi https://www.comedi.org"); 148 MODULE_DESCRIPTION("Comedi low-level driver"); 149 MODULE_LICENSE("GPL"); 150