xref: /freebsd/sys/dev/spibus/spibus.c (revision a0409676120c1e558d0ade943019934e0f15118d)
1 /*-
2  * Copyright (c) 2006 M. Warner Losh <imp@FreeBSD.org>
3  *
4  * Redistribution and use in source and binary forms, with or without
5  * modification, are permitted provided that the following conditions
6  * are met:
7  * 1. Redistributions of source code must retain the above copyright
8  *    notice, this list of conditions and the following disclaimer.
9  * 2. Redistributions in binary form must reproduce the above copyright
10  *    notice, this list of conditions and the following disclaimer in the
11  *    documentation and/or other materials provided with the distribution.
12  *
13  * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
14  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
15  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
16  * ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
17  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
18  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
19  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
20  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
21  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
22  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
23  * SUCH DAMAGE.
24  *
25  */
26 
27 #include <sys/cdefs.h>
28 __FBSDID("$FreeBSD$");
29 
30 #include <sys/param.h>
31 #include <sys/systm.h>
32 #include <sys/malloc.h>
33 #include <sys/module.h>
34 #include <sys/kernel.h>
35 #include <sys/queue.h>
36 #include <sys/sysctl.h>
37 #include <sys/types.h>
38 
39 #include <sys/bus.h>
40 #include <machine/bus.h>
41 #include <sys/rman.h>
42 #include <machine/resource.h>
43 
44 #include <dev/spibus/spibusvar.h>
45 #include <dev/spibus/spi.h>
46 #include "spibus_if.h"
47 
48 static int
49 spibus_probe(device_t dev)
50 {
51 
52 	device_set_desc(dev, "SPI bus");
53 	return (BUS_PROBE_DEFAULT);
54 }
55 
56 static int
57 spibus_attach(device_t dev)
58 {
59 	struct spibus_softc *sc = SPIBUS_SOFTC(dev);
60 
61 	sc->dev = dev;
62 	bus_enumerate_hinted_children(dev);
63 	return (bus_generic_attach(dev));
64 }
65 
66 /*
67  * Since this is not a self-enumerating bus, and since we always add
68  * children in attach, we have to always delete children here.
69  */
70 static int
71 spibus_detach(device_t dev)
72 {
73 	int err;
74 
75 	if ((err = bus_generic_detach(dev)) != 0)
76 		return (err);
77 	device_delete_children(dev);
78 
79 	return (0);
80 }
81 
82 static int
83 spibus_suspend(device_t dev)
84 {
85 	return (bus_generic_suspend(dev));
86 }
87 
88 static
89 int
90 spibus_resume(device_t dev)
91 {
92 	return (bus_generic_resume(dev));
93 }
94 
95 static int
96 spibus_print_child(device_t dev, device_t child)
97 {
98 	struct spibus_ivar *devi = SPIBUS_IVAR(child);
99 	int retval = 0;
100 
101 	retval += bus_print_child_header(dev, child);
102 	retval += printf(" at cs %d", devi->cs);
103 	retval += printf(" mode %d", devi->mode);
104 	retval += resource_list_print_type(&devi->rl, "irq",
105 	    SYS_RES_IRQ, "%jd");
106 	retval += bus_print_child_footer(dev, child);
107 
108 	return (retval);
109 }
110 
111 static void
112 spibus_probe_nomatch(device_t bus, device_t child)
113 {
114 	struct spibus_ivar *devi = SPIBUS_IVAR(child);
115 
116 	device_printf(bus, "<unknown card> at cs %d mode %d\n", devi->cs,
117 	    devi->mode);
118 	return;
119 }
120 
121 static int
122 spibus_child_location_str(device_t bus, device_t child, char *buf,
123     size_t buflen)
124 {
125 	struct spibus_ivar *devi = SPIBUS_IVAR(child);
126 	int cs;
127 
128 	cs = devi->cs & ~SPIBUS_CS_HIGH; /* trim 'cs high' bit */
129 	snprintf(buf, buflen, "bus=%d cs=%d", device_get_unit(bus), cs);
130 	return (0);
131 }
132 
133 static int
134 spibus_child_pnpinfo_str(device_t bus, device_t child, char *buf,
135     size_t buflen)
136 {
137 	*buf = '\0';
138 	return (0);
139 }
140 
141 static int
142 spibus_read_ivar(device_t bus, device_t child, int which, uintptr_t *result)
143 {
144 	struct spibus_ivar *devi = SPIBUS_IVAR(child);
145 
146 	switch (which) {
147 	default:
148 		return (EINVAL);
149 	case SPIBUS_IVAR_CS:
150 		*(uint32_t *)result = devi->cs;
151 		break;
152 	case SPIBUS_IVAR_MODE:
153 		*(uint32_t *)result = devi->mode;
154 		break;
155 	case SPIBUS_IVAR_CLOCK:
156 		*(uint32_t *)result = devi->clock;
157 		break;
158 	}
159 	return (0);
160 }
161 
162 static int
163 spibus_write_ivar(device_t bus, device_t child, int which, uintptr_t value)
164 {
165 	struct spibus_ivar *devi = SPIBUS_IVAR(child);
166 
167 	if (devi == NULL || device_get_parent(child) != bus)
168 		return (EDOOFUS);
169 
170 	switch (which) {
171 	case SPIBUS_IVAR_CLOCK:
172 		/* Any non-zero value is allowed for max clock frequency. */
173 		if (value == 0)
174 			return (EINVAL);
175 		devi->clock = (uint32_t)value;
176 		break;
177 	case SPIBUS_IVAR_CS:
178 		 /* Chip select cannot be changed. */
179 		return (EINVAL);
180 	case SPIBUS_IVAR_MODE:
181 		/* Valid SPI modes are 0-3. */
182 		if (value > 3)
183 			return (EINVAL);
184 		devi->mode = (uint32_t)value;
185 		break;
186 	default:
187 		return (EINVAL);
188 	}
189 
190 	return (0);
191 }
192 
193 static device_t
194 spibus_add_child(device_t dev, u_int order, const char *name, int unit)
195 {
196 	device_t child;
197 	struct spibus_ivar *devi;
198 
199 	child = device_add_child_ordered(dev, order, name, unit);
200 	if (child == NULL)
201 		return (child);
202 	devi = malloc(sizeof(struct spibus_ivar), M_DEVBUF, M_NOWAIT | M_ZERO);
203 	if (devi == NULL) {
204 		device_delete_child(dev, child);
205 		return (0);
206 	}
207 	resource_list_init(&devi->rl);
208 	device_set_ivars(child, devi);
209 	return (child);
210 }
211 
212 static void
213 spibus_hinted_child(device_t bus, const char *dname, int dunit)
214 {
215 	device_t child;
216 	int irq;
217 	struct spibus_ivar *devi;
218 
219 	child = BUS_ADD_CHILD(bus, 0, dname, dunit);
220 	devi = SPIBUS_IVAR(child);
221 	devi->mode = SPIBUS_MODE_NONE;
222 	resource_int_value(dname, dunit, "clock", &devi->clock);
223 	resource_int_value(dname, dunit, "cs", &devi->cs);
224 	resource_int_value(dname, dunit, "mode", &devi->mode);
225 	if (resource_int_value(dname, dunit, "irq", &irq) == 0) {
226 		if (bus_set_resource(child, SYS_RES_IRQ, 0, irq, 1) != 0)
227 			device_printf(bus,
228 			    "Warning: bus_set_resource() failed\n");
229 	}
230 }
231 
232 static struct resource_list *
233 spibus_get_resource_list(device_t bus __unused, device_t child)
234 {
235 	struct spibus_ivar *devi;
236 
237 	devi = SPIBUS_IVAR(child);
238 	return (&devi->rl);
239 }
240 
241 static int
242 spibus_transfer_impl(device_t dev, device_t child, struct spi_command *cmd)
243 {
244 	return (SPIBUS_TRANSFER(device_get_parent(dev), child, cmd));
245 }
246 
247 static device_method_t spibus_methods[] = {
248 	/* Device interface */
249 	DEVMETHOD(device_probe,		spibus_probe),
250 	DEVMETHOD(device_attach,	spibus_attach),
251 	DEVMETHOD(device_detach,	spibus_detach),
252 	DEVMETHOD(device_shutdown,	bus_generic_shutdown),
253 	DEVMETHOD(device_suspend,	spibus_suspend),
254 	DEVMETHOD(device_resume,	spibus_resume),
255 
256 	/* Bus interface */
257 	DEVMETHOD(bus_setup_intr,	bus_generic_setup_intr),
258 	DEVMETHOD(bus_teardown_intr,	bus_generic_teardown_intr),
259 	DEVMETHOD(bus_release_resource,	bus_generic_release_resource),
260 	DEVMETHOD(bus_activate_resource, bus_generic_activate_resource),
261 	DEVMETHOD(bus_deactivate_resource, bus_generic_deactivate_resource),
262 	DEVMETHOD(bus_adjust_resource,	bus_generic_adjust_resource),
263 	DEVMETHOD(bus_alloc_resource,	bus_generic_rl_alloc_resource),
264 	DEVMETHOD(bus_get_resource,	bus_generic_rl_get_resource),
265 	DEVMETHOD(bus_set_resource,	bus_generic_rl_set_resource),
266 	DEVMETHOD(bus_get_resource_list, spibus_get_resource_list),
267 
268 	DEVMETHOD(bus_add_child,	spibus_add_child),
269 	DEVMETHOD(bus_print_child,	spibus_print_child),
270 	DEVMETHOD(bus_probe_nomatch,	spibus_probe_nomatch),
271 	DEVMETHOD(bus_read_ivar,	spibus_read_ivar),
272 	DEVMETHOD(bus_write_ivar,	spibus_write_ivar),
273 	DEVMETHOD(bus_child_pnpinfo_str, spibus_child_pnpinfo_str),
274 	DEVMETHOD(bus_child_location_str, spibus_child_location_str),
275 	DEVMETHOD(bus_hinted_child,	spibus_hinted_child),
276 
277 	/* spibus interface */
278 	DEVMETHOD(spibus_transfer,	spibus_transfer_impl),
279 
280 	DEVMETHOD_END
281 };
282 
283 driver_t spibus_driver = {
284 	"spibus",
285 	spibus_methods,
286 	sizeof(struct spibus_softc)
287 };
288 
289 devclass_t	spibus_devclass;
290 
291 DRIVER_MODULE(spibus, spi, spibus_driver, spibus_devclass, 0, 0);
292 MODULE_VERSION(spibus, 1);
293