FreeBSD/Linux Kernel Cross Reference
sys/dev/gpio/gpioow.c
1 /* $NetBSD: gpioow.c,v 1.5 2008/05/04 14:01:14 xtraeme Exp $ */
2 /* $OpenBSD: gpioow.c,v 1.1 2006/03/04 16:27:03 grange Exp $ */
3
4 /*
5 * Copyright (c) 2006 Alexander Yurchenko <grange@openbsd.org>
6 *
7 * Permission to use, copy, modify, and distribute this software for any
8 * purpose with or without fee is hereby granted, provided that the above
9 * copyright notice and this permission notice appear in all copies.
10 *
11 * THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES
12 * WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF
13 * MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR
14 * ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
15 * WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN
16 * ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF
17 * OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
18 */
19
20 #include <sys/cdefs.h>
21 __KERNEL_RCSID(0, "$NetBSD: gpioow.c,v 1.5 2008/05/04 14:01:14 xtraeme Exp $");
22
23 /*
24 * 1-Wire bus bit-banging through GPIO pin.
25 */
26
27 #include <sys/param.h>
28 #include <sys/systm.h>
29 #include <sys/device.h>
30 #include <sys/gpio.h>
31
32 #include <dev/gpio/gpiovar.h>
33
34 #include <dev/onewire/onewirevar.h>
35
36 #define GPIOOW_NPINS 1
37 #define GPIOOW_PIN_DATA 0
38
39 struct gpioow_softc {
40 void * sc_gpio;
41 struct gpio_pinmap sc_map;
42 int __map[GPIOOW_NPINS];
43
44 struct onewire_bus sc_ow_bus;
45 device_t sc_ow_dev;
46
47 int sc_data;
48 int sc_dying;
49 };
50
51 int gpioow_match(device_t, cfdata_t, void *);
52 void gpioow_attach(device_t, device_t, void *);
53 int gpioow_detach(device_t, int);
54 int gpioow_activate(device_t, enum devact);
55
56 int gpioow_ow_reset(void *);
57 int gpioow_ow_bit(void *, int);
58
59 void gpioow_bb_rx(void *);
60 void gpioow_bb_tx(void *);
61 int gpioow_bb_get(void *);
62 void gpioow_bb_set(void *, int);
63
64 CFATTACH_DECL_NEW(gpioow, sizeof(struct gpioow_softc),
65 gpioow_match, gpioow_attach, gpioow_detach, gpioow_activate);
66
67 extern struct cfdriver gpioow_cd;
68
69 static const struct onewire_bbops gpioow_bbops = {
70 gpioow_bb_rx,
71 gpioow_bb_tx,
72 gpioow_bb_get,
73 gpioow_bb_set
74 };
75
76 int
77 gpioow_match(device_t parent, cfdata_t cf,
78 void *aux)
79 {
80 return 1;
81 }
82
83 void
84 gpioow_attach(device_t parent, device_t self, void *aux)
85 {
86 struct gpioow_softc *sc = device_private(self);
87 struct gpio_attach_args *ga = aux;
88 struct onewirebus_attach_args oba;
89 int caps;
90
91 /* Check that we have enough pins */
92 if (gpio_npins(ga->ga_mask) != GPIOOW_NPINS) {
93 printf(": invalid pin mask\n");
94 return;
95 }
96
97 /* Map pins */
98 sc->sc_gpio = ga->ga_gpio;
99 sc->sc_map.pm_map = sc->__map;
100 if (gpio_pin_map(sc->sc_gpio, ga->ga_offset, ga->ga_mask,
101 &sc->sc_map)) {
102 printf(": can't map pins\n");
103 return;
104 }
105
106 /* Configure data pin */
107 caps = gpio_pin_caps(sc->sc_gpio, &sc->sc_map, GPIOOW_PIN_DATA);
108 if (!(caps & GPIO_PIN_OUTPUT)) {
109 printf(": data pin is unable to drive output\n");
110 goto fail;
111 }
112 if (!(caps & GPIO_PIN_INPUT)) {
113 printf(": data pin is unable to read input\n");
114 goto fail;
115 }
116 printf(": DATA[%d]", sc->sc_map.pm_map[GPIOOW_PIN_DATA]);
117 sc->sc_data = GPIO_PIN_OUTPUT;
118 if (caps & GPIO_PIN_OPENDRAIN) {
119 printf(" open-drain");
120 sc->sc_data |= GPIO_PIN_OPENDRAIN;
121 } else if ((caps & GPIO_PIN_PUSHPULL) && (caps & GPIO_PIN_TRISTATE)) {
122 printf(" push-pull tri-state");
123 sc->sc_data |= GPIO_PIN_PUSHPULL;
124 }
125 if (caps & GPIO_PIN_PULLUP) {
126 printf(" pull-up");
127 sc->sc_data |= GPIO_PIN_PULLUP;
128 }
129 gpio_pin_ctl(sc->sc_gpio, &sc->sc_map, GPIOOW_PIN_DATA, sc->sc_data);
130
131 printf("\n");
132
133 /* Attach 1-Wire bus */
134 sc->sc_ow_bus.bus_cookie = sc;
135 sc->sc_ow_bus.bus_reset = gpioow_ow_reset;
136 sc->sc_ow_bus.bus_bit = gpioow_ow_bit;
137
138 bzero(&oba, sizeof(oba));
139 oba.oba_bus = &sc->sc_ow_bus;
140 sc->sc_ow_dev = config_found(self, &oba, onewirebus_print);
141
142 return;
143
144 fail:
145 gpio_pin_unmap(sc->sc_gpio, &sc->sc_map);
146 }
147
148 int
149 gpioow_detach(device_t self, int flags)
150 {
151 struct gpioow_softc *sc = device_private(self);
152 int rv = 0;
153
154 if (sc->sc_ow_dev != NULL)
155 rv = config_detach(sc->sc_ow_dev, flags);
156
157 return (rv);
158 }
159
160 int
161 gpioow_activate(device_t self, enum devact act)
162 {
163 struct gpioow_softc *sc = device_private(self);
164 int rv = 0;
165
166 switch (act) {
167 case DVACT_ACTIVATE:
168 return (EOPNOTSUPP);
169 case DVACT_DEACTIVATE:
170 sc->sc_dying = 1;
171 if (sc->sc_ow_dev != NULL)
172 rv = config_deactivate(sc->sc_ow_dev);
173 break;
174 }
175
176 return (rv);
177 }
178
179 int
180 gpioow_ow_reset(void *arg)
181 {
182 return (onewire_bb_reset(&gpioow_bbops, arg));
183 }
184
185 int
186 gpioow_ow_bit(void *arg, int value)
187 {
188 return (onewire_bb_bit(&gpioow_bbops, arg, value));
189 }
190
191 void
192 gpioow_bb_rx(void *arg)
193 {
194 struct gpioow_softc *sc = arg;
195 int data = sc->sc_data;
196
197 data &= ~(GPIO_PIN_INPUT | GPIO_PIN_OUTPUT | GPIO_PIN_TRISTATE);
198 data |= GPIO_PIN_INPUT;
199 if (data & GPIO_PIN_PUSHPULL)
200 data |= GPIO_PIN_TRISTATE;
201 if (sc->sc_data != data) {
202 sc->sc_data = data;
203 gpio_pin_ctl(sc->sc_gpio, &sc->sc_map, GPIOOW_PIN_DATA,
204 sc->sc_data);
205 }
206 }
207
208 void
209 gpioow_bb_tx(void *arg)
210 {
211 struct gpioow_softc *sc = arg;
212 int data = sc->sc_data;
213
214 data &= ~(GPIO_PIN_INPUT | GPIO_PIN_OUTPUT | GPIO_PIN_TRISTATE);
215 data |= GPIO_PIN_OUTPUT;
216 if (sc->sc_data != data) {
217 sc->sc_data = data;
218 gpio_pin_ctl(sc->sc_gpio, &sc->sc_map, GPIOOW_PIN_DATA,
219 sc->sc_data);
220 }
221 }
222
223 int
224 gpioow_bb_get(void *arg)
225 {
226 struct gpioow_softc *sc = arg;
227
228 return (gpio_pin_read(sc->sc_gpio, &sc->sc_map, GPIOOW_PIN_DATA) ==
229 GPIO_PIN_HIGH ? 1 : 0);
230 }
231
232 void
233 gpioow_bb_set(void *arg, int value)
234 {
235 struct gpioow_softc *sc = arg;
236
237 gpio_pin_write(sc->sc_gpio, &sc->sc_map, GPIOOW_PIN_DATA,
238 value ? GPIO_PIN_HIGH : GPIO_PIN_LOW);
239 }
Cache object: 786b3471f291c39fd8f589ab380f86c9
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