xref: /netbsd-src/sys/dev/gpio/gpiosim.c (revision 901e7e84758515fbf39dfc064cb0b45ab146d8b0)
1 /* $NetBSD: gpiosim.c,v 1.24 2023/05/10 00:09:39 riastradh Exp $ */
2 /*      $OpenBSD: gpiosim.c,v 1.1 2008/11/23 18:46:49 mbalmer Exp $	*/
3 
4 /*
5  * Copyright (c) 2007 - 2011, 2013 Marc Balmer <marc@msys.ch>
6  * All rights reserved.
7  *
8  * Permission to use, copy, modify, and distribute this software for any
9  * purpose with or without fee is hereby granted, provided that the above
10  * copyright notice and this permission notice appear in all copies.
11  *
12  * THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES
13  * WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF
14  * MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR
15  * ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
16  * WHATSOEVER RESULTING FROM LOSS OF MIND, USE, DATA OR PROFITS, WHETHER IN
17  * AN ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT
18  * OF OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
19  */
20 
21 /* 64 bit wide GPIO simulator  */
22 
23 #include <sys/param.h>
24 #include <sys/systm.h>
25 #include <sys/device.h>
26 #include <sys/gpio.h>
27 #include <sys/malloc.h>
28 #include <sys/module.h>
29 #include <sys/sysctl.h>
30 #include <sys/ioccom.h>
31 #include <dev/gpio/gpiovar.h>
32 
33 #include "gpiosim.h"
34 #include "ioconf.h"
35 
36 #define	GPIOSIM_NPINS	64
37 
38 struct gpiosim_softc {
39 	device_t		sc_dev;
40 	device_t		sc_gdev;	/* gpio that attaches here */
41 	uint64_t		sc_state;
42 	struct gpio_chipset_tag	sc_gpio_gc;
43 	gpio_pin_t		sc_gpio_pins[GPIOSIM_NPINS];
44 
45 	struct sysctllog	*sc_log;
46 };
47 
48 static int	gpiosim_match(device_t, cfdata_t, void *);
49 static void	gpiosim_attach(device_t, device_t, void *);
50 static int	gpiosim_detach(device_t, int);
51 static int	gpiosim_sysctl(SYSCTLFN_PROTO);
52 
53 static int	gpiosim_pin_read(void *, int);
54 static void	gpiosim_pin_write(void *, int, int);
55 static void	gpiosim_pin_ctl(void *, int, int);
56 
57 CFATTACH_DECL_NEW(gpiosim, sizeof(struct gpiosim_softc), gpiosim_match,
58     gpiosim_attach, gpiosim_detach, NULL);
59 
60 static int
61 gpiosim_match(device_t parent, cfdata_t match, void *aux)
62 {
63 	return 1;
64 }
65 
66 void
67 gpiosimattach(int num __unused)
68 {
69 	cfdata_t cf;
70 	int n, err;
71 
72 	err = config_cfattach_attach(gpiosim_cd.cd_name, &gpiosim_ca);
73 	if (err)
74 		printf("%s: unable to register cfattach\n", gpiosim_cd.cd_name);
75 
76 	for (n = 0; n < NGPIOSIM; n++) {
77 		cf = malloc(sizeof(*cf), M_DEVBUF, M_WAITOK);
78 		cf->cf_name = "gpiosim";
79 		cf->cf_atname = "gpiosim";
80 		cf->cf_unit = n;
81 		cf->cf_fstate = FSTATE_NOTFOUND;
82 		config_attach_pseudo(cf);
83 	}
84 }
85 
86 static void
87 gpiosim_attach(device_t parent, device_t self, void *aux)
88 {
89 	struct gpiosim_softc *sc = device_private(self);
90 	struct gpiobus_attach_args gba;
91 	const struct sysctlnode *node;
92 	int i;
93 
94 	sc->sc_dev = self;
95 
96 	printf("%s", device_xname(sc->sc_dev));
97 
98 	/* initialize pin array */
99 	for (i = 0; i < GPIOSIM_NPINS; i++) {
100 		sc->sc_gpio_pins[i].pin_num = i;
101 		sc->sc_gpio_pins[i].pin_caps = GPIO_PIN_INPUT |
102 		    GPIO_PIN_OUTPUT | GPIO_PIN_OPENDRAIN |
103 		    GPIO_PIN_PULLUP | GPIO_PIN_PULLDOWN |
104 		    GPIO_PIN_INVIN | GPIO_PIN_INVOUT;
105 
106 		/* read initial state */
107 		sc->sc_gpio_pins[i].pin_flags = GPIO_PIN_INPUT;
108 	}
109 	sc->sc_state = 0;
110 
111 	/* create controller tag */
112 	sc->sc_gpio_gc.gp_cookie = sc;
113 	sc->sc_gpio_gc.gp_pin_read = gpiosim_pin_read;
114 	sc->sc_gpio_gc.gp_pin_write = gpiosim_pin_write;
115 	sc->sc_gpio_gc.gp_pin_ctl = gpiosim_pin_ctl;
116 
117 	/* gba.gba_name = "gpio"; */
118 	gba.gba_gc = &sc->sc_gpio_gc;
119 	gba.gba_pins = sc->sc_gpio_pins;
120 	gba.gba_npins = GPIOSIM_NPINS;
121 
122 	if (!pmf_device_register(self, NULL, NULL))
123 		aprint_error_dev(self, "couldn't establish power handler\n");
124 
125         sysctl_createv(&sc->sc_log, 0, NULL, &node,
126             0,
127             CTLTYPE_NODE, device_xname(sc->sc_dev),
128             SYSCTL_DESCR("GPIO simulator"),
129             NULL, 0, NULL, 0,
130             CTL_HW, CTL_CREATE, CTL_EOL);
131 
132         if (node == NULL) {
133 		aprint_error(": can't create sysctl node\n");
134                 return;
135 	}
136 
137         sysctl_createv(&sc->sc_log, 0, &node, NULL,
138             CTLFLAG_READWRITE,
139             CTLTYPE_QUAD, "value",
140             SYSCTL_DESCR("Current GPIO simulator value"),
141             gpiosim_sysctl, 0, (void *)sc, 0,
142 	    CTL_CREATE, CTL_EOL);
143 
144 	aprint_normal(": simulating %d pins\n", GPIOSIM_NPINS);
145 	sc->sc_gdev = config_found(self, &gba, gpiobus_print, CFARGS_NONE);
146 }
147 
148 static int
149 gpiosim_detach(device_t self, int flags)
150 {
151 	struct gpiosim_softc *sc = device_private(self);
152 	int error;
153 
154 	/* Detach the gpio driver that attached here */
155 	error = config_detach_children(self, flags);
156 	if (error)
157 		return error;
158 
159 	pmf_device_deregister(self);
160 	if (sc->sc_log != NULL) {
161 		sysctl_teardown(&sc->sc_log);
162 		sc->sc_log = NULL;
163 	}
164 	return 0;
165 }
166 
167 static int
168 gpiosim_sysctl(SYSCTLFN_ARGS)
169 {
170 	struct sysctlnode node;
171 	struct gpiosim_softc *sc;
172 	uint64_t val, error;
173 
174 	node = *rnode;
175 	sc = node.sysctl_data;
176 
177 	node.sysctl_data = &val;
178 
179 	val = sc->sc_state;
180 	error = sysctl_lookup(SYSCTLFN_CALL(&node));
181 	if (error || newp == NULL)
182 		return error;
183 
184 	sc->sc_state = val;
185 	return 0;
186 }
187 
188 static int
189 gpiosim_pin_read(void *arg, int pin)
190 {
191 	struct gpiosim_softc *sc = arg;
192 
193 	if (sc->sc_state & (1LL << pin))
194 		return GPIO_PIN_HIGH;
195 	else
196 		return GPIO_PIN_LOW;
197 }
198 
199 static void
200 gpiosim_pin_write(void *arg, int pin, int value)
201 {
202 	struct gpiosim_softc *sc = arg;
203 
204 	if (value == 0)
205 		sc->sc_state &= ~(1LL << pin);
206 	else
207 		sc->sc_state |= (1LL << pin);
208 }
209 
210 static void
211 gpiosim_pin_ctl(void *arg, int pin, int flags)
212 {
213 	struct gpiosim_softc *sc = arg;
214 
215 	sc->sc_gpio_pins[pin].pin_flags = flags;
216 }
217 
218 MODULE(MODULE_CLASS_DRIVER, gpiosim, "gpio");
219 
220 #ifdef _MODULE
221 static const struct cfiattrdata gpiobus_iattrdata = {
222 	"gpiobus", 0, { { NULL, NULL, 0 },}
223 };
224 static const struct cfiattrdata *const gpiosim_attrs[] = {
225 	&gpiobus_iattrdata, NULL
226 };
227 CFDRIVER_DECL(gpiosim, DV_DULL, gpiosim_attrs);
228 extern struct cfattach gpiosim_ca;
229 static int gpiosimloc[] = {
230 	-1,
231 	-1,
232 	-1
233 };
234 static struct cfdata gpiosim_cfdata[] = {
235 	{
236 		.cf_name = "gpiosim",
237 		.cf_atname = "gpiosim",
238 		.cf_unit = 0,
239 		.cf_fstate = FSTATE_STAR,
240 		.cf_loc = gpiosimloc,
241 		.cf_flags = 0,
242 		.cf_pspec = NULL,
243 	},
244 	{ NULL, NULL, 0, FSTATE_NOTFOUND, NULL, 0, NULL }
245 };
246 #endif
247 
248 static int
249 gpiosim_modcmd(modcmd_t cmd, void *opaque)
250 {
251 #ifdef _MODULE
252 	int error = 0;
253 #endif
254 	switch (cmd) {
255 	case MODULE_CMD_INIT:
256 #ifdef _MODULE
257 		error = config_cfdriver_attach(&gpiosim_cd);
258 		if (error)
259 			return error;
260 
261 		error = config_cfattach_attach(gpiosim_cd.cd_name,
262 		    &gpiosim_ca);
263 		if (error) {
264 			config_cfdriver_detach(&gpiosim_cd);
265 			aprint_error("%s: unable to register cfattach\n",
266 			    gpiosim_cd.cd_name);
267 			return error;
268 		}
269 		error = config_cfdata_attach(gpiosim_cfdata, 1);
270 		if (error) {
271 			config_cfattach_detach(gpiosim_cd.cd_name,
272 			    &gpiosim_ca);
273 			config_cfdriver_detach(&gpiosim_cd);
274 			aprint_error("%s: unable to register cfdata\n",
275 			    gpiosim_cd.cd_name);
276 			return error;
277 		}
278 		config_attach_pseudo(gpiosim_cfdata);
279 #endif
280 		return 0;
281 	case MODULE_CMD_FINI:
282 #ifdef _MODULE
283 		error = config_cfdata_detach(gpiosim_cfdata);
284 		if (error)
285 			return error;
286 
287 		config_cfattach_detach(gpiosim_cd.cd_name, &gpiosim_ca);
288 		config_cfdriver_detach(&gpiosim_cd);
289 #endif
290 		return 0;
291 	case MODULE_CMD_AUTOUNLOAD:
292 		/* no auto-unload */
293 		return EBUSY;
294 	default:
295 		return ENOTTY;
296 	}
297 }
298