Annotation of sys/dev/gpio/gpio.c, Revision 1.1.1.1
1.1 nbrk 1: /* $OpenBSD: gpio.c,v 1.7 2006/03/26 18:48:17 grange Exp $ */
2:
3: /*
4: * Copyright (c) 2004, 2006 Alexander Yurchenko <grange@openbsd.org>
5: *
6: * Permission to use, copy, modify, and distribute this software for any
7: * purpose with or without fee is hereby granted, provided that the above
8: * copyright notice and this permission notice appear in all copies.
9: *
10: * THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES
11: * WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF
12: * MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR
13: * ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
14: * WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN
15: * ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF
16: * OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
17: */
18:
19: /*
20: * General Purpose Input/Output framework.
21: */
22:
23: #include <sys/param.h>
24: #include <sys/systm.h>
25: #include <sys/conf.h>
26: #include <sys/device.h>
27: #include <sys/fcntl.h>
28: #include <sys/ioctl.h>
29: #include <sys/gpio.h>
30: #include <sys/vnode.h>
31:
32: #include <dev/gpio/gpiovar.h>
33:
34: struct gpio_softc {
35: struct device sc_dev;
36:
37: gpio_chipset_tag_t sc_gc; /* our GPIO controller */
38: gpio_pin_t *sc_pins; /* pins array */
39: int sc_npins; /* total number of pins */
40:
41: int sc_opened;
42: };
43:
44: int gpio_match(struct device *, void *, void *);
45: void gpio_attach(struct device *, struct device *, void *);
46: int gpio_detach(struct device *, int);
47: int gpio_search(struct device *, void *, void *);
48: int gpio_print(void *, const char *);
49:
50: struct cfattach gpio_ca = {
51: sizeof (struct gpio_softc),
52: gpio_match,
53: gpio_attach,
54: gpio_detach
55: };
56:
57: struct cfdriver gpio_cd = {
58: NULL, "gpio", DV_DULL
59: };
60:
61: int
62: gpio_match(struct device *parent, void *match, void *aux)
63: {
64: struct cfdata *cf = match;
65: struct gpiobus_attach_args *gba = aux;
66:
67: if (strcmp(gba->gba_name, cf->cf_driver->cd_name) != 0)
68: return (0);
69:
70: return (1);
71: }
72:
73: void
74: gpio_attach(struct device *parent, struct device *self, void *aux)
75: {
76: struct gpio_softc *sc = (struct gpio_softc *)self;
77: struct gpiobus_attach_args *gba = aux;
78:
79: sc->sc_gc = gba->gba_gc;
80: sc->sc_pins = gba->gba_pins;
81: sc->sc_npins = gba->gba_npins;
82:
83: printf(": %d pins\n", sc->sc_npins);
84:
85: /*
86: * Attach all devices that can be connected to the GPIO pins
87: * described in the kernel configuration file.
88: */
89: config_search(gpio_search, self, sc);
90: }
91:
92: int
93: gpio_detach(struct device *self, int flags)
94: {
95: int maj, mn;
96:
97: /* Locate the major number */
98: for (maj = 0; maj < nchrdev; maj++)
99: if (cdevsw[maj].d_open == gpioopen)
100: break;
101:
102: /* Nuke the vnodes for any open instances (calls close) */
103: mn = self->dv_unit;
104: vdevgone(maj, mn, mn, VCHR);
105:
106: return (0);
107: }
108:
109: int
110: gpio_search(struct device *parent, void *arg, void *aux)
111: {
112: struct cfdata *cf = arg;
113: struct gpio_attach_args ga;
114:
115: ga.ga_gpio = aux;
116: ga.ga_offset = cf->cf_loc[0];
117: ga.ga_mask = cf->cf_loc[1];
118:
119: if (cf->cf_attach->ca_match(parent, cf, &ga) > 0)
120: config_attach(parent, cf, &ga, gpio_print);
121:
122: return (0);
123: }
124:
125: int
126: gpio_print(void *aux, const char *pnp)
127: {
128: struct gpio_attach_args *ga = aux;
129: int i;
130:
131: printf(" pins");
132: for (i = 0; i < 32; i++)
133: if (ga->ga_mask & (1 << i))
134: printf(" %d", ga->ga_offset + i);
135:
136: return (UNCONF);
137: }
138:
139: int
140: gpiobus_print(void *aux, const char *pnp)
141: {
142: struct gpiobus_attach_args *gba = aux;
143:
144: if (pnp != NULL)
145: printf("%s at %s", gba->gba_name, pnp);
146:
147: return (UNCONF);
148: }
149:
150: int
151: gpio_pin_map(void *gpio, int offset, u_int32_t mask, struct gpio_pinmap *map)
152: {
153: struct gpio_softc *sc = gpio;
154: int npins, pin, i;
155:
156: npins = gpio_npins(mask);
157: if (npins > sc->sc_npins)
158: return (1);
159:
160: for (npins = 0, i = 0; i < 32; i++)
161: if (mask & (1 << i)) {
162: pin = offset + i;
163: if (pin < 0 || pin >= sc->sc_npins)
164: return (1);
165: if (sc->sc_pins[pin].pin_mapped)
166: return (1);
167: sc->sc_pins[pin].pin_mapped = 1;
168: map->pm_map[npins++] = pin;
169: }
170: map->pm_size = npins;
171:
172: return (0);
173: }
174:
175: void
176: gpio_pin_unmap(void *gpio, struct gpio_pinmap *map)
177: {
178: struct gpio_softc *sc = gpio;
179: int pin, i;
180:
181: for (i = 0; i < map->pm_size; i++) {
182: pin = map->pm_map[i];
183: sc->sc_pins[pin].pin_mapped = 0;
184: }
185: }
186:
187: int
188: gpio_pin_read(void *gpio, struct gpio_pinmap *map, int pin)
189: {
190: struct gpio_softc *sc = gpio;
191:
192: return (gpiobus_pin_read(sc->sc_gc, map->pm_map[pin]));
193: }
194:
195: void
196: gpio_pin_write(void *gpio, struct gpio_pinmap *map, int pin, int value)
197: {
198: struct gpio_softc *sc = gpio;
199:
200: return (gpiobus_pin_write(sc->sc_gc, map->pm_map[pin], value));
201: }
202:
203: void
204: gpio_pin_ctl(void *gpio, struct gpio_pinmap *map, int pin, int flags)
205: {
206: struct gpio_softc *sc = gpio;
207:
208: return (gpiobus_pin_ctl(sc->sc_gc, map->pm_map[pin], flags));
209: }
210:
211: int
212: gpio_pin_caps(void *gpio, struct gpio_pinmap *map, int pin)
213: {
214: struct gpio_softc *sc = gpio;
215:
216: return (sc->sc_pins[map->pm_map[pin]].pin_caps);
217: }
218:
219: int
220: gpio_npins(u_int32_t mask)
221: {
222: int npins, i;
223:
224: for (npins = 0, i = 0; i < 32; i++)
225: if (mask & (1 << i))
226: npins++;
227:
228: return (npins);
229: }
230:
231: int
232: gpioopen(dev_t dev, int flag, int mode, struct proc *p)
233: {
234: struct gpio_softc *sc;
235:
236: sc = (struct gpio_softc *)device_lookup(&gpio_cd, minor(dev));
237: if (sc == NULL)
238: return (ENXIO);
239:
240: if (sc->sc_opened)
241: return (EBUSY);
242: sc->sc_opened = 1;
243:
244: return (0);
245: }
246:
247: int
248: gpioclose(dev_t dev, int flag, int mode, struct proc *p)
249: {
250: struct gpio_softc *sc;
251:
252: sc = (struct gpio_softc *)device_lookup(&gpio_cd, minor(dev));
253: sc->sc_opened = 0;
254:
255: return (0);
256: }
257:
258: int
259: gpioioctl(dev_t dev, u_long cmd, caddr_t data, int flag, struct proc *p)
260: {
261: struct gpio_softc *sc;
262: gpio_chipset_tag_t gc;
263: struct gpio_info *info;
264: struct gpio_pin_op *op;
265: struct gpio_pin_ctl *ctl;
266: int pin, value, flags;
267:
268: sc = (struct gpio_softc *)device_lookup(&gpio_cd, minor(dev));
269: gc = sc->sc_gc;
270:
271: switch (cmd) {
272: case GPIOINFO:
273: info = (struct gpio_info *)data;
274:
275: info->gpio_npins = sc->sc_npins;
276: break;
277: case GPIOPINREAD:
278: op = (struct gpio_pin_op *)data;
279:
280: pin = op->gp_pin;
281: if (pin < 0 || pin >= sc->sc_npins)
282: return (EINVAL);
283:
284: /* return read value */
285: op->gp_value = gpiobus_pin_read(gc, pin);
286: break;
287: case GPIOPINWRITE:
288: if ((flag & FWRITE) == 0)
289: return (EBADF);
290:
291: op = (struct gpio_pin_op *)data;
292:
293: pin = op->gp_pin;
294: if (pin < 0 || pin >= sc->sc_npins)
295: return (EINVAL);
296: if (sc->sc_pins[pin].pin_mapped)
297: return (EBUSY);
298:
299: value = op->gp_value;
300: if (value != GPIO_PIN_LOW && value != GPIO_PIN_HIGH)
301: return (EINVAL);
302:
303: gpiobus_pin_write(gc, pin, value);
304: /* return old value */
305: op->gp_value = sc->sc_pins[pin].pin_state;
306: /* update current value */
307: sc->sc_pins[pin].pin_state = value;
308: break;
309: case GPIOPINTOGGLE:
310: if ((flag & FWRITE) == 0)
311: return (EBADF);
312:
313: op = (struct gpio_pin_op *)data;
314:
315: pin = op->gp_pin;
316: if (pin < 0 || pin >= sc->sc_npins)
317: return (EINVAL);
318: if (sc->sc_pins[pin].pin_mapped)
319: return (EBUSY);
320:
321: value = (sc->sc_pins[pin].pin_state == GPIO_PIN_LOW ?
322: GPIO_PIN_HIGH : GPIO_PIN_LOW);
323: gpiobus_pin_write(gc, pin, value);
324: /* return old value */
325: op->gp_value = sc->sc_pins[pin].pin_state;
326: /* update current value */
327: sc->sc_pins[pin].pin_state = value;
328: break;
329: case GPIOPINCTL:
330: if ((flag & FWRITE) == 0)
331: return (EBADF);
332:
333: ctl = (struct gpio_pin_ctl *)data;
334:
335: pin = ctl->gp_pin;
336: if (pin < 0 || pin >= sc->sc_npins)
337: return (EINVAL);
338: if (sc->sc_pins[pin].pin_mapped)
339: return (EBUSY);
340:
341: flags = ctl->gp_flags;
342: /* check that the controller supports all requested flags */
343: if ((flags & sc->sc_pins[pin].pin_caps) != flags)
344: return (ENODEV);
345:
346: ctl->gp_caps = sc->sc_pins[pin].pin_caps;
347: /* return old value */
348: ctl->gp_flags = sc->sc_pins[pin].pin_flags;
349: if (flags > 0) {
350: gpiobus_pin_ctl(gc, pin, flags);
351: /* update current value */
352: sc->sc_pins[pin].pin_flags = flags;
353: }
354: break;
355: default:
356: return (ENOTTY);
357: }
358:
359: return (0);
360: }
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