xref: /freebsd/sys/dev/gpio/ofw_gpiobus.c (revision 59e2ff550c448126b988150ce800cdf73bb5103e)
1 /*-
2  * Copyright (c) 2009, Nathan Whitehorn <nwhitehorn@FreeBSD.org>
3  * Copyright (c) 2013, Luiz Otavio O Souza <loos@FreeBSD.org>
4  * Copyright (c) 2013 The FreeBSD Foundation
5  * All rights reserved.
6  *
7  * Redistribution and use in source and binary forms, with or without
8  * modification, are permitted provided that the following conditions
9  * are met:
10  * 1. Redistributions of source code must retain the above copyright
11  *    notice unmodified, this list of conditions, and the following
12  *    disclaimer.
13  * 2. Redistributions in binary form must reproduce the above copyright
14  *    notice, this list of conditions and the following disclaimer in the
15  *    documentation and/or other materials provided with the distribution.
16  *
17  * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
18  * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
19  * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
20  * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
21  * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
22  * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
23  * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
24  * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
25  * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
26  * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
27  */
28 
29 #include <sys/cdefs.h>
30 __FBSDID("$FreeBSD$");
31 
32 #include <sys/param.h>
33 #include <sys/systm.h>
34 #include <sys/bus.h>
35 #include <sys/kernel.h>
36 #include <sys/malloc.h>
37 #include <sys/module.h>
38 
39 #include <dev/gpio/gpiobusvar.h>
40 #include <dev/ofw/ofw_bus.h>
41 
42 #include "gpiobus_if.h"
43 
44 static struct ofw_gpiobus_devinfo *ofw_gpiobus_setup_devinfo(device_t,
45 	device_t, phandle_t);
46 static void ofw_gpiobus_destroy_devinfo(device_t, struct ofw_gpiobus_devinfo *);
47 static int ofw_gpiobus_parse_gpios_impl(device_t, phandle_t, char *,
48 	struct gpiobus_softc *, struct gpiobus_pin **);
49 
50 device_t
51 ofw_gpiobus_add_fdt_child(device_t bus, const char *drvname, phandle_t child)
52 {
53 	device_t childdev;
54 	int i;
55 	struct gpiobus_ivar *devi;
56 	struct ofw_gpiobus_devinfo *dinfo;
57 
58 	/*
59 	 * Check to see if we already have a child for @p child, and if so
60 	 * return it.
61 	 */
62 	childdev = ofw_bus_find_child_device_by_phandle(bus, child);
63 	if (childdev != NULL)
64 		return (childdev);
65 
66 	/*
67 	 * Set up the GPIO child and OFW bus layer devinfo and add it to bus.
68 	 */
69 	childdev = device_add_child(bus, drvname, -1);
70 	if (childdev == NULL)
71 		return (NULL);
72 	dinfo = ofw_gpiobus_setup_devinfo(bus, childdev, child);
73 	if (dinfo == NULL) {
74 		device_delete_child(bus, childdev);
75 		return (NULL);
76 	}
77 	if (device_probe_and_attach(childdev) != 0) {
78 		ofw_gpiobus_destroy_devinfo(bus, dinfo);
79 		device_delete_child(bus, childdev);
80 		return (NULL);
81 	}
82 	/* Use the child name as pin name. */
83 	devi = &dinfo->opd_dinfo;
84 	for (i = 0; i < devi->npins; i++)
85 		GPIOBUS_PIN_SETNAME(bus, devi->pins[i],
86 		    device_get_nameunit(childdev));
87 
88 	return (childdev);
89 }
90 
91 int
92 ofw_gpiobus_parse_gpios(device_t consumer, char *pname,
93 	struct gpiobus_pin **pins)
94 {
95 
96 	return (ofw_gpiobus_parse_gpios_impl(consumer,
97 	    ofw_bus_get_node(consumer), pname, NULL, pins));
98 }
99 
100 void
101 ofw_gpiobus_register_provider(device_t provider)
102 {
103 	phandle_t node;
104 
105 	node = ofw_bus_get_node(provider);
106 	OF_device_register_xref(OF_xref_from_node(node), provider);
107 }
108 
109 void
110 ofw_gpiobus_unregister_provider(device_t provider)
111 {
112 	phandle_t node;
113 
114 	node = ofw_bus_get_node(provider);
115 	OF_device_register_xref(OF_xref_from_node(node), NULL);
116 }
117 
118 static struct ofw_gpiobus_devinfo *
119 ofw_gpiobus_setup_devinfo(device_t bus, device_t child, phandle_t node)
120 {
121 	int i, npins;
122 	struct gpiobus_ivar *devi;
123 	struct gpiobus_pin *pins;
124 	struct gpiobus_softc *sc;
125 	struct ofw_gpiobus_devinfo *dinfo;
126 
127 	sc = device_get_softc(bus);
128 	dinfo = malloc(sizeof(*dinfo), M_DEVBUF, M_NOWAIT | M_ZERO);
129 	if (dinfo == NULL)
130 		return (NULL);
131 	if (ofw_bus_gen_setup_devinfo(&dinfo->opd_obdinfo, node) != 0) {
132 		free(dinfo, M_DEVBUF);
133 		return (NULL);
134 	}
135 	/* Parse the gpios property for the child. */
136 	npins = ofw_gpiobus_parse_gpios_impl(child, node, "gpios", sc, &pins);
137 	if (npins <= 0) {
138 		ofw_bus_gen_destroy_devinfo(&dinfo->opd_obdinfo);
139 		free(dinfo, M_DEVBUF);
140 		return (NULL);
141 	}
142 	/* Initialize the irq resource list. */
143 	resource_list_init(&dinfo->opd_dinfo.rl);
144 	/* Allocate the child ivars and copy the parsed pin data. */
145 	devi = &dinfo->opd_dinfo;
146 	devi->npins = (uint32_t)npins;
147 	if (gpiobus_alloc_ivars(devi) != 0) {
148 		free(pins, M_DEVBUF);
149 		ofw_gpiobus_destroy_devinfo(bus, dinfo);
150 		return (NULL);
151 	}
152 	for (i = 0; i < devi->npins; i++) {
153 		devi->flags[i] = pins[i].flags;
154 		devi->pins[i] = pins[i].pin;
155 	}
156 	free(pins, M_DEVBUF);
157 	/* Parse the interrupt resources. */
158 	if (ofw_bus_intr_to_rl(bus, node, &dinfo->opd_dinfo.rl, NULL) != 0) {
159 		ofw_gpiobus_destroy_devinfo(bus, dinfo);
160 		return (NULL);
161 	}
162 	device_set_ivars(child, dinfo);
163 
164 	return (dinfo);
165 }
166 
167 static void
168 ofw_gpiobus_destroy_devinfo(device_t bus, struct ofw_gpiobus_devinfo *dinfo)
169 {
170 	int i;
171 	struct gpiobus_ivar *devi;
172 	struct gpiobus_softc *sc;
173 
174 	sc = device_get_softc(bus);
175 	devi = &dinfo->opd_dinfo;
176 	for (i = 0; i < devi->npins; i++) {
177 		if (devi->pins[i] > sc->sc_npins)
178 			continue;
179 		sc->sc_pins[devi->pins[i]].mapped = 0;
180 	}
181 	gpiobus_free_ivars(devi);
182 	resource_list_free(&dinfo->opd_dinfo.rl);
183 	ofw_bus_gen_destroy_devinfo(&dinfo->opd_obdinfo);
184 	free(dinfo, M_DEVBUF);
185 }
186 
187 static int
188 ofw_gpiobus_parse_gpios_impl(device_t consumer, phandle_t cnode, char *pname,
189 	struct gpiobus_softc *bussc, struct gpiobus_pin **pins)
190 {
191 	int gpiocells, i, j, ncells, npins;
192 	pcell_t *gpios;
193 	phandle_t gpio;
194 
195 	ncells = OF_getencprop_alloc(cnode, pname, sizeof(*gpios),
196             (void **)&gpios);
197 	if (ncells == -1) {
198 		device_printf(consumer,
199 		    "Warning: No %s specified in fdt data; "
200 		    "device may not function.\n", pname);
201 		return (-1);
202 	}
203 	/*
204 	 * The gpio-specifier is controller independent, the first pcell has
205 	 * the reference to the GPIO controller phandler.
206 	 * Count the number of encoded gpio-specifiers on the first pass.
207 	 */
208 	i = 0;
209 	npins = 0;
210 	while (i < ncells) {
211 		/* Allow NULL specifiers. */
212 		if (gpios[i] == 0) {
213 			npins++;
214 			i++;
215 			continue;
216 		}
217 		gpio = OF_node_from_xref(gpios[i]);
218 		/* If we have bussc, ignore devices from other gpios. */
219 		if (bussc != NULL)
220 			if (ofw_bus_get_node(bussc->sc_dev) != gpio)
221 				return (0);
222 		/*
223 		 * Check for gpio-controller property and read the #gpio-cells
224 		 * for this GPIO controller.
225 		 */
226 		if (!OF_hasprop(gpio, "gpio-controller") ||
227 		    OF_getencprop(gpio, "#gpio-cells", &gpiocells,
228 		    sizeof(gpiocells)) < 0) {
229 			device_printf(consumer,
230 			    "gpio reference is not a gpio-controller.\n");
231 			free(gpios, M_OFWPROP);
232 			return (-1);
233 		}
234 		if (ncells - i < gpiocells + 1) {
235 			device_printf(consumer,
236 			    "%s cells doesn't match #gpio-cells.\n", pname);
237 			return (-1);
238 		}
239 		npins++;
240 		i += gpiocells + 1;
241 	}
242 	if (npins == 0 || pins == NULL) {
243 		if (npins == 0)
244 			device_printf(consumer, "no pin specified in %s.\n",
245 			    pname);
246 		free(gpios, M_OFWPROP);
247 		return (npins);
248 	}
249 	*pins = malloc(sizeof(struct gpiobus_pin) * npins, M_DEVBUF,
250 	    M_NOWAIT | M_ZERO);
251 	if (*pins == NULL) {
252 		free(gpios, M_OFWPROP);
253 		return (-1);
254 	}
255 	/* Decode the gpio specifier on the second pass. */
256 	i = 0;
257 	j = 0;
258 	while (i < ncells) {
259 		/* Allow NULL specifiers. */
260 		if (gpios[i] == 0) {
261 			j++;
262 			i++;
263 			continue;
264 		}
265 		gpio = OF_node_from_xref(gpios[i]);
266 		/* Read gpio-cells property for this GPIO controller. */
267 		if (OF_getencprop(gpio, "#gpio-cells", &gpiocells,
268 		    sizeof(gpiocells)) < 0) {
269 			device_printf(consumer,
270 			    "gpio does not have the #gpio-cells property.\n");
271 			goto fail;
272 		}
273 		/* Return the device reference for the GPIO controller. */
274 		(*pins)[j].dev = OF_device_from_xref(gpios[i]);
275 		if ((*pins)[j].dev == NULL) {
276 			device_printf(consumer,
277 			    "no device registered for the gpio controller.\n");
278 			goto fail;
279 		}
280 		/*
281 		 * If the gpiobus softc is NULL we use the GPIO_GET_BUS() to
282 		 * retrieve it.  The GPIO_GET_BUS() method is only valid after
283 		 * the child is probed and attached.
284 		 */
285 		if (bussc == NULL) {
286 			if (GPIO_GET_BUS((*pins)[j].dev) == NULL) {
287 				device_printf(consumer,
288 				    "no gpiobus reference for %s.\n",
289 				    device_get_nameunit((*pins)[j].dev));
290 				goto fail;
291 			}
292 			bussc = device_get_softc(GPIO_GET_BUS((*pins)[j].dev));
293 		}
294 		/* Get the GPIO pin number and flags. */
295 		if (gpio_map_gpios((*pins)[j].dev, cnode, gpio, gpiocells,
296 		    &gpios[i + 1], &(*pins)[j].pin, &(*pins)[j].flags) != 0) {
297 			device_printf(consumer,
298 			    "cannot map the gpios specifier.\n");
299 			goto fail;
300 		}
301 		/* Reserve the GPIO pin. */
302 		if (gpiobus_map_pin(bussc->sc_busdev, (*pins)[j].pin) != 0)
303 			goto fail;
304 		j++;
305 		i += gpiocells + 1;
306 	}
307 	free(gpios, M_OFWPROP);
308 
309 	return (npins);
310 
311 fail:
312 	free(gpios, M_OFWPROP);
313 	free(*pins, M_DEVBUF);
314 	return (-1);
315 }
316 
317 static int
318 ofw_gpiobus_probe(device_t dev)
319 {
320 
321 	if (ofw_bus_get_node(dev) == -1)
322 		return (ENXIO);
323 	device_set_desc(dev, "OFW GPIO bus");
324 
325 	return (0);
326 }
327 
328 static int
329 ofw_gpiobus_attach(device_t dev)
330 {
331 	int err;
332 	phandle_t child;
333 
334 	err = gpiobus_init_softc(dev);
335 	if (err != 0)
336 		return (err);
337 	bus_generic_probe(dev);
338 	bus_enumerate_hinted_children(dev);
339 	/*
340 	 * Attach the children represented in the device tree.
341 	 */
342 	for (child = OF_child(ofw_bus_get_node(dev)); child != 0;
343 	    child = OF_peer(child)) {
344 		if (!OF_hasprop(child, "gpios"))
345 			continue;
346 		if (ofw_gpiobus_add_fdt_child(dev, NULL, child) == NULL)
347 			continue;
348 	}
349 
350 	return (bus_generic_attach(dev));
351 }
352 
353 static device_t
354 ofw_gpiobus_add_child(device_t dev, u_int order, const char *name, int unit)
355 {
356 	device_t child;
357 	struct ofw_gpiobus_devinfo *devi;
358 
359 	child = device_add_child_ordered(dev, order, name, unit);
360 	if (child == NULL)
361 		return (child);
362 	devi = malloc(sizeof(struct ofw_gpiobus_devinfo), M_DEVBUF,
363 	    M_NOWAIT | M_ZERO);
364 	if (devi == NULL) {
365 		device_delete_child(dev, child);
366 		return (0);
367 	}
368 
369 	/*
370 	 * NULL all the OFW-related parts of the ivars for non-OFW
371 	 * children.
372 	 */
373 	devi->opd_obdinfo.obd_node = -1;
374 	devi->opd_obdinfo.obd_name = NULL;
375 	devi->opd_obdinfo.obd_compat = NULL;
376 	devi->opd_obdinfo.obd_type = NULL;
377 	devi->opd_obdinfo.obd_model = NULL;
378 
379 	device_set_ivars(child, devi);
380 
381 	return (child);
382 }
383 
384 static const struct ofw_bus_devinfo *
385 ofw_gpiobus_get_devinfo(device_t bus, device_t dev)
386 {
387 	struct ofw_gpiobus_devinfo *dinfo;
388 
389 	dinfo = device_get_ivars(dev);
390 
391 	return (&dinfo->opd_obdinfo);
392 }
393 
394 static device_method_t ofw_gpiobus_methods[] = {
395 	/* Device interface */
396 	DEVMETHOD(device_probe,		ofw_gpiobus_probe),
397 	DEVMETHOD(device_attach,	ofw_gpiobus_attach),
398 
399 	/* Bus interface */
400 	DEVMETHOD(bus_child_pnpinfo_str,	ofw_bus_gen_child_pnpinfo_str),
401 	DEVMETHOD(bus_add_child,	ofw_gpiobus_add_child),
402 
403 	/* ofw_bus interface */
404 	DEVMETHOD(ofw_bus_get_devinfo,	ofw_gpiobus_get_devinfo),
405 	DEVMETHOD(ofw_bus_get_compat,	ofw_bus_gen_get_compat),
406 	DEVMETHOD(ofw_bus_get_model,	ofw_bus_gen_get_model),
407 	DEVMETHOD(ofw_bus_get_name,	ofw_bus_gen_get_name),
408 	DEVMETHOD(ofw_bus_get_node,	ofw_bus_gen_get_node),
409 	DEVMETHOD(ofw_bus_get_type,	ofw_bus_gen_get_type),
410 
411 	DEVMETHOD_END
412 };
413 
414 static devclass_t ofwgpiobus_devclass;
415 
416 DEFINE_CLASS_1(gpiobus, ofw_gpiobus_driver, ofw_gpiobus_methods,
417     sizeof(struct gpiobus_softc), gpiobus_driver);
418 DRIVER_MODULE(ofw_gpiobus, gpio, ofw_gpiobus_driver, ofwgpiobus_devclass, 0, 0);
419 MODULE_VERSION(ofw_gpiobus, 1);
420 MODULE_DEPEND(ofw_gpiobus, gpiobus, 1, 1, 1);
421