1 // SPDX-License-Identifier: GPL-2.0+
2 /*
3 * comedi/drivers/amplc_pc236_common.c
4 * Common support code for "amplc_pc236" and "amplc_pci236".
5 *
6 * Copyright (C) 2002-2014 MEV Ltd. <https://www.mev.co.uk/>
7 *
8 * COMEDI - Linux Control and Measurement Device Interface
9 * Copyright (C) 2000 David A. Schleef <ds@schleef.org>
10 */
11
12 #include <linux/module.h>
13 #include <linux/interrupt.h>
14
15 #include "../comedidev.h"
16
17 #include "amplc_pc236.h"
18 #include "8255.h"
19
pc236_intr_update(struct comedi_device * dev,bool enable)20 static void pc236_intr_update(struct comedi_device *dev, bool enable)
21 {
22 const struct pc236_board *board = dev->board_ptr;
23 struct pc236_private *devpriv = dev->private;
24 unsigned long flags;
25
26 spin_lock_irqsave(&dev->spinlock, flags);
27 devpriv->enable_irq = enable;
28 if (board->intr_update_cb)
29 board->intr_update_cb(dev, enable);
30 spin_unlock_irqrestore(&dev->spinlock, flags);
31 }
32
33 /*
34 * This function is called when an interrupt occurs to check whether
35 * the interrupt has been marked as enabled and was generated by the
36 * board. If so, the function prepares the hardware for the next
37 * interrupt.
38 * Returns false if the interrupt should be ignored.
39 */
pc236_intr_check(struct comedi_device * dev)40 static bool pc236_intr_check(struct comedi_device *dev)
41 {
42 const struct pc236_board *board = dev->board_ptr;
43 struct pc236_private *devpriv = dev->private;
44 bool retval = false;
45 unsigned long flags;
46
47 spin_lock_irqsave(&dev->spinlock, flags);
48 if (devpriv->enable_irq) {
49 if (board->intr_chk_clr_cb)
50 retval = board->intr_chk_clr_cb(dev);
51 else
52 retval = true;
53 }
54 spin_unlock_irqrestore(&dev->spinlock, flags);
55
56 return retval;
57 }
58
pc236_intr_insn(struct comedi_device * dev,struct comedi_subdevice * s,struct comedi_insn * insn,unsigned int * data)59 static int pc236_intr_insn(struct comedi_device *dev,
60 struct comedi_subdevice *s, struct comedi_insn *insn,
61 unsigned int *data)
62 {
63 data[1] = 0;
64 return insn->n;
65 }
66
pc236_intr_cmdtest(struct comedi_device * dev,struct comedi_subdevice * s,struct comedi_cmd * cmd)67 static int pc236_intr_cmdtest(struct comedi_device *dev,
68 struct comedi_subdevice *s,
69 struct comedi_cmd *cmd)
70 {
71 int err = 0;
72
73 /* Step 1 : check if triggers are trivially valid */
74
75 err |= comedi_check_trigger_src(&cmd->start_src, TRIG_NOW);
76 err |= comedi_check_trigger_src(&cmd->scan_begin_src, TRIG_EXT);
77 err |= comedi_check_trigger_src(&cmd->convert_src, TRIG_FOLLOW);
78 err |= comedi_check_trigger_src(&cmd->scan_end_src, TRIG_COUNT);
79 err |= comedi_check_trigger_src(&cmd->stop_src, TRIG_NONE);
80
81 if (err)
82 return 1;
83
84 /* Step 2a : make sure trigger sources are unique */
85 /* Step 2b : and mutually compatible */
86
87 /* Step 3: check it arguments are trivially valid */
88
89 err |= comedi_check_trigger_arg_is(&cmd->start_arg, 0);
90 err |= comedi_check_trigger_arg_is(&cmd->scan_begin_arg, 0);
91 err |= comedi_check_trigger_arg_is(&cmd->convert_arg, 0);
92 err |= comedi_check_trigger_arg_is(&cmd->scan_end_arg,
93 cmd->chanlist_len);
94 err |= comedi_check_trigger_arg_is(&cmd->stop_arg, 0);
95
96 if (err)
97 return 3;
98
99 /* Step 4: fix up any arguments */
100
101 /* Step 5: check channel list if it exists */
102
103 return 0;
104 }
105
pc236_intr_cmd(struct comedi_device * dev,struct comedi_subdevice * s)106 static int pc236_intr_cmd(struct comedi_device *dev, struct comedi_subdevice *s)
107 {
108 pc236_intr_update(dev, true);
109
110 return 0;
111 }
112
pc236_intr_cancel(struct comedi_device * dev,struct comedi_subdevice * s)113 static int pc236_intr_cancel(struct comedi_device *dev,
114 struct comedi_subdevice *s)
115 {
116 pc236_intr_update(dev, false);
117
118 return 0;
119 }
120
pc236_interrupt(int irq,void * d)121 static irqreturn_t pc236_interrupt(int irq, void *d)
122 {
123 struct comedi_device *dev = d;
124 struct comedi_subdevice *s = dev->read_subdev;
125 bool handled;
126
127 handled = pc236_intr_check(dev);
128 if (dev->attached && handled) {
129 unsigned short val = 0;
130
131 comedi_buf_write_samples(s, &val, 1);
132 comedi_handle_events(dev, s);
133 }
134 return IRQ_RETVAL(handled);
135 }
136
amplc_pc236_common_attach(struct comedi_device * dev,unsigned long iobase,unsigned int irq,unsigned long req_irq_flags)137 int amplc_pc236_common_attach(struct comedi_device *dev, unsigned long iobase,
138 unsigned int irq, unsigned long req_irq_flags)
139 {
140 struct comedi_subdevice *s;
141 int ret;
142
143 dev->iobase = iobase;
144
145 ret = comedi_alloc_subdevices(dev, 2);
146 if (ret)
147 return ret;
148
149 s = &dev->subdevices[0];
150 /* digital i/o subdevice (8255) */
151 ret = subdev_8255_init(dev, s, NULL, 0x00);
152 if (ret)
153 return ret;
154
155 s = &dev->subdevices[1];
156 dev->read_subdev = s;
157 s->type = COMEDI_SUBD_UNUSED;
158 pc236_intr_update(dev, false);
159 if (irq) {
160 if (request_irq(irq, pc236_interrupt, req_irq_flags,
161 dev->board_name, dev) >= 0) {
162 dev->irq = irq;
163 s->type = COMEDI_SUBD_DI;
164 s->subdev_flags = SDF_READABLE | SDF_CMD_READ;
165 s->n_chan = 1;
166 s->maxdata = 1;
167 s->range_table = &range_digital;
168 s->insn_bits = pc236_intr_insn;
169 s->len_chanlist = 1;
170 s->do_cmdtest = pc236_intr_cmdtest;
171 s->do_cmd = pc236_intr_cmd;
172 s->cancel = pc236_intr_cancel;
173 }
174 }
175
176 return 0;
177 }
178 EXPORT_SYMBOL_GPL(amplc_pc236_common_attach);
179
amplc_pc236_common_init(void)180 static int __init amplc_pc236_common_init(void)
181 {
182 return 0;
183 }
184 module_init(amplc_pc236_common_init);
185
amplc_pc236_common_exit(void)186 static void __exit amplc_pc236_common_exit(void)
187 {
188 }
189 module_exit(amplc_pc236_common_exit);
190
191 MODULE_AUTHOR("Comedi https://www.comedi.org");
192 MODULE_DESCRIPTION("Comedi helper for amplc_pc236 and amplc_pci236");
193 MODULE_LICENSE("GPL");
194