1/* $NetBSD: gpiosim.c,v 1.12 2011/08/29 15:14:04 mbalmer Exp $ */
2/*      $OpenBSD: gpiosim.c,v 1.1 2008/11/23 18:46:49 mbalmer Exp $	*/
3
4/*
5 * Copyright (c) 2007, 2008, 2009, 2010, 2011 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/* 32 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#define	GPIOSIM_NPINS	32
34
35struct gpiosim_softc {
36	device_t		sc_dev;
37	device_t		sc_gdev;	/* gpio that attaches here */
38	uint32_t		sc_state;
39	struct gpio_chipset_tag	sc_gpio_gc;
40	gpio_pin_t		sc_gpio_pins[GPIOSIM_NPINS];
41
42	struct sysctllog	*sc_log;
43};
44
45static int	gpiosim_match(device_t, cfdata_t, void *);
46void		gpiosimattach(int);
47static void	gpiosim_attach(device_t, device_t, void *);
48static int	gpiosim_detach(device_t, int);
49static int	gpiosim_sysctl(SYSCTLFN_PROTO);
50
51static int	gpiosim_pin_read(void *, int);
52static void	gpiosim_pin_write(void *, int, int);
53static void	gpiosim_pin_ctl(void *, int, int);
54
55CFATTACH_DECL_NEW(gpiosim, sizeof(struct gpiosim_softc), gpiosim_match,
56    gpiosim_attach, gpiosim_detach, NULL);
57
58extern struct cfdriver gpiosim_cd;
59
60static int
61gpiosim_match(device_t parent, cfdata_t match, void *aux)
62{
63	return 1;
64}
65
66void
67gpiosimattach(int num)
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 < num; 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
86static void
87gpiosim_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		sc->sc_state = 0;
109
110		/* create controller tag */
111		sc->sc_gpio_gc.gp_cookie = sc;
112		sc->sc_gpio_gc.gp_pin_read = gpiosim_pin_read;
113		sc->sc_gpio_gc.gp_pin_write = gpiosim_pin_write;
114		sc->sc_gpio_gc.gp_pin_ctl = gpiosim_pin_ctl;
115
116		/* gba.gba_name = "gpio"; */
117		gba.gba_gc = &sc->sc_gpio_gc;
118		gba.gba_pins = sc->sc_gpio_pins;
119		gba.gba_npins = GPIOSIM_NPINS;
120	}
121
122	pmf_device_register(self, NULL, NULL);
123
124	sysctl_createv(NULL, 0, NULL, NULL,
125            CTLFLAG_PERMANENT,
126            CTLTYPE_NODE, "hw", NULL,
127            NULL, 0, NULL, 0,
128            CTL_HW, CTL_EOL);
129        sysctl_createv(&sc->sc_log, 0, NULL, &node,
130            0,
131            CTLTYPE_NODE, device_xname(sc->sc_dev),
132            SYSCTL_DESCR("GPIO simulator"),
133            NULL, 0, NULL, 0,
134            CTL_HW, CTL_CREATE, CTL_EOL);
135
136        if (node == NULL) {
137		printf(": can't create sysctl node\n");
138                return;
139	}
140
141        sysctl_createv(&sc->sc_log, 0, &node, NULL,
142            CTLFLAG_READWRITE,
143            CTLTYPE_INT, "value",
144            SYSCTL_DESCR("Current GPIO simulator value"),
145            gpiosim_sysctl, 0, sc, 0,
146	    CTL_CREATE, CTL_EOL);
147
148	printf(": simulating %d pins\n", GPIOSIM_NPINS);
149	sc->sc_gdev = config_found_ia(self, "gpiobus", &gba, gpiobus_print);
150}
151
152static int
153gpiosim_detach(device_t self, int flags)
154{
155	struct gpiosim_softc *sc = device_private(self);
156
157	/* Detach the gpio driver that attached here */
158	if (sc->sc_gdev != NULL)
159		config_detach(sc->sc_gdev, 0);
160
161	pmf_device_deregister(self);
162	if (sc->sc_log != NULL) {
163		sysctl_teardown(&sc->sc_log);
164		sc->sc_log = NULL;
165	}
166	return 0;
167}
168
169static int
170gpiosim_sysctl(SYSCTLFN_ARGS)
171{
172	struct sysctlnode node;
173	struct gpiosim_softc *sc;
174	int val, error;
175
176	node = *rnode;
177	sc = node.sysctl_data;
178
179	node.sysctl_data = &val;
180
181	val = sc->sc_state;
182	error = sysctl_lookup(SYSCTLFN_CALL(&node));
183	if (error || newp == NULL)
184		return error;
185
186	sc->sc_state = val;
187	return 0;
188}
189
190static int
191gpiosim_pin_read(void *arg, int pin)
192{
193	struct gpiosim_softc *sc = arg;
194
195	if (sc->sc_state & (1 << pin))
196		return GPIO_PIN_HIGH;
197	else
198		return GPIO_PIN_LOW;
199}
200
201static void
202gpiosim_pin_write(void *arg, int pin, int value)
203{
204	struct gpiosim_softc *sc = arg;
205
206	if (value == 0)
207		sc->sc_state &= ~(1 << pin);
208	else
209		sc->sc_state |= (1 << pin);
210}
211
212static void
213gpiosim_pin_ctl(void *arg, int pin, int flags)
214{
215	struct gpiosim_softc *sc = arg;
216
217	sc->sc_gpio_pins[pin].pin_flags = flags;
218}
219
220MODULE(MODULE_CLASS_DRIVER, gpiosim, "gpio");
221
222#ifdef _MODULE
223static const struct cfiattrdata gpiobus_iattrdata = {
224	"gpiobus", 0, { { NULL, NULL, 0 },}
225};
226static const struct cfiattrdata *const gpiosim_attrs[] = {
227	&gpiobus_iattrdata, NULL
228};
229CFDRIVER_DECL(gpiosim, DV_DULL, gpiosim_attrs);
230extern struct cfattach gpiosim_ca;
231static int gpiosimloc[] = {
232	-1,
233	-1,
234	-1
235};
236static struct cfdata gpiosim_cfdata[] = {
237	{
238		.cf_name = "gpiosim",
239		.cf_atname = "gpiosim",
240		.cf_unit = 0,
241		.cf_fstate = FSTATE_STAR,
242		.cf_loc = gpiosimloc,
243		.cf_flags = 0,
244		.cf_pspec = NULL,
245	},
246	{ NULL, NULL, 0, FSTATE_NOTFOUND, NULL, 0, NULL }
247};
248#endif
249
250static int
251gpiosim_modcmd(modcmd_t cmd, void *opaque)
252{
253#ifdef _MODULE
254	int error = 0;
255#endif
256	switch (cmd) {
257	case MODULE_CMD_INIT:
258#ifdef _MODULE
259		error = config_cfdriver_attach(&gpiosim_cd);
260		if (error)
261			return error;
262
263		error = config_cfattach_attach(gpiosim_cd.cd_name,
264		    &gpiosim_ca);
265		if (error) {
266			config_cfdriver_detach(&gpiosim_cd);
267			aprint_error("%s: unable to register cfattach\n",
268			    gpiosim_cd.cd_name);
269			return error;
270		}
271		error = config_cfdata_attach(gpiosim_cfdata, 1);
272		if (error) {
273			config_cfattach_detach(gpiosim_cd.cd_name,
274			    &gpiosim_ca);
275			config_cfdriver_detach(&gpiosim_cd);
276			aprint_error("%s: unable to register cfdata\n",
277			    gpiosim_cd.cd_name);
278			return error;
279		}
280		config_attach_pseudo(gpiosim_cfdata);
281#endif
282		return 0;
283	case MODULE_CMD_FINI:
284#ifdef _MODULE
285		error = config_cfdata_detach(gpiosim_cfdata);
286		if (error)
287			return error;
288
289		config_cfattach_detach(gpiosim_cd.cd_name, &gpiosim_ca);
290		config_cfdriver_detach(&gpiosim_cd);
291#endif
292		return 0;
293	case MODULE_CMD_AUTOUNLOAD:
294		/* no auto-unload */
295		return EBUSY;
296	default:
297		return ENOTTY;
298	}
299}
300