xref: /freebsd/sys/dev/spibus/spibus.c (revision 2a63c3be158216222d89a073dcbd6a72ee4aab5a)
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/sbuf.h>
37 #include <sys/sysctl.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 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 int
71 spibus_detach(device_t dev)
72 {
73 	return (device_delete_children(dev));
74 }
75 
76 static int
77 spibus_suspend(device_t dev)
78 {
79 	return (bus_generic_suspend(dev));
80 }
81 
82 static
83 int
84 spibus_resume(device_t dev)
85 {
86 	return (bus_generic_resume(dev));
87 }
88 
89 static int
90 spibus_print_child(device_t dev, device_t child)
91 {
92 	struct spibus_ivar *devi = SPIBUS_IVAR(child);
93 	int retval = 0;
94 
95 	retval += bus_print_child_header(dev, child);
96 	retval += printf(" at cs %d", devi->cs);
97 	retval += printf(" mode %d", devi->mode);
98 	retval += resource_list_print_type(&devi->rl, "irq",
99 	    SYS_RES_IRQ, "%jd");
100 	retval += bus_print_child_footer(dev, child);
101 
102 	return (retval);
103 }
104 
105 void
106 spibus_probe_nomatch(device_t bus, device_t child)
107 {
108 	struct spibus_ivar *devi = SPIBUS_IVAR(child);
109 
110 	device_printf(bus, "<unknown card> at cs %d mode %d\n", devi->cs,
111 	    devi->mode);
112 	return;
113 }
114 
115 int
116 spibus_child_location(device_t bus, device_t child, struct sbuf *sb)
117 {
118 	struct spibus_ivar *devi = SPIBUS_IVAR(child);
119 	int cs;
120 
121 	cs = devi->cs & ~SPIBUS_CS_HIGH; /* trim 'cs high' bit */
122 	sbuf_printf(sb, "bus=%d cs=%d", device_get_unit(bus), cs);
123 	return (0);
124 }
125 
126 int
127 spibus_read_ivar(device_t bus, device_t child, int which, uintptr_t *result)
128 {
129 	struct spibus_ivar *devi = SPIBUS_IVAR(child);
130 
131 	switch (which) {
132 	default:
133 		return (EINVAL);
134 	case SPIBUS_IVAR_CS:
135 		*(uint32_t *)result = devi->cs;
136 		break;
137 	case SPIBUS_IVAR_MODE:
138 		*(uint32_t *)result = devi->mode;
139 		break;
140 	case SPIBUS_IVAR_CLOCK:
141 		*(uint32_t *)result = devi->clock;
142 		break;
143 	case SPIBUS_IVAR_CS_DELAY:
144 		*(uint32_t *)result = devi->cs_delay;
145 		break;
146 	}
147 	return (0);
148 }
149 
150 int
151 spibus_write_ivar(device_t bus, device_t child, int which, uintptr_t value)
152 {
153 	struct spibus_ivar *devi = SPIBUS_IVAR(child);
154 
155 	if (devi == NULL || device_get_parent(child) != bus)
156 		return (EDOOFUS);
157 
158 	switch (which) {
159 	case SPIBUS_IVAR_CLOCK:
160 		/* Any non-zero value is allowed for max clock frequency. */
161 		if (value == 0)
162 			return (EINVAL);
163 		devi->clock = (uint32_t)value;
164 		break;
165 	case SPIBUS_IVAR_CS:
166 		 /* Chip select cannot be changed. */
167 		return (EINVAL);
168 	case SPIBUS_IVAR_MODE:
169 		/* Valid SPI modes are 0-3. */
170 		if (value > 3)
171 			return (EINVAL);
172 		devi->mode = (uint32_t)value;
173 		break;
174 	case SPIBUS_IVAR_CS_DELAY:
175 		devi->cs_delay = (uint32_t)value;
176 		break;
177 	default:
178 		return (EINVAL);
179 	}
180 
181 	return (0);
182 }
183 
184 device_t
185 spibus_add_child_common(device_t dev, u_int order, const char *name, int unit,
186     size_t ivars_size)
187 {
188 	device_t child;
189 	struct spibus_ivar *devi;
190 
191 	child = device_add_child_ordered(dev, order, name, unit);
192 	if (child == NULL)
193 		return (child);
194 	devi = malloc(ivars_size, M_DEVBUF, M_NOWAIT | M_ZERO);
195 	if (devi == NULL) {
196 		device_delete_child(dev, child);
197 		return (0);
198 	}
199 	resource_list_init(&devi->rl);
200 	device_set_ivars(child, devi);
201 	return (child);
202 }
203 
204 static device_t
205 spibus_add_child(device_t dev, u_int order, const char *name, int unit)
206 {
207 	return (spibus_add_child_common(
208 	    dev, order, name, unit, sizeof(struct spibus_ivar)));
209 }
210 
211 static void
212 spibus_hinted_child(device_t bus, const char *dname, int dunit)
213 {
214 	device_t child;
215 	int irq;
216 	struct spibus_ivar *devi;
217 
218 	child = BUS_ADD_CHILD(bus, 0, dname, dunit);
219 	devi = SPIBUS_IVAR(child);
220 	devi->mode = SPIBUS_MODE_NONE;
221 	resource_int_value(dname, dunit, "clock", &devi->clock);
222 	resource_int_value(dname, dunit, "cs", &devi->cs);
223 	resource_int_value(dname, dunit, "mode", &devi->mode);
224 	if (resource_int_value(dname, dunit, "irq", &irq) == 0) {
225 		if (bus_set_resource(child, SYS_RES_IRQ, 0, irq, 1) != 0)
226 			device_printf(bus,
227 			    "Warning: bus_set_resource() failed\n");
228 	}
229 }
230 
231 static struct resource_list *
232 spibus_get_resource_list(device_t bus __unused, device_t child)
233 {
234 	struct spibus_ivar *devi;
235 
236 	devi = SPIBUS_IVAR(child);
237 	return (&devi->rl);
238 }
239 
240 static int
241 spibus_transfer_impl(device_t dev, device_t child, struct spi_command *cmd)
242 {
243 	return (SPIBUS_TRANSFER(device_get_parent(dev), child, cmd));
244 }
245 
246 static device_method_t spibus_methods[] = {
247 	/* Device interface */
248 	DEVMETHOD(device_probe,		spibus_probe),
249 	DEVMETHOD(device_attach,	spibus_attach),
250 	DEVMETHOD(device_detach,	spibus_detach),
251 	DEVMETHOD(device_shutdown,	bus_generic_shutdown),
252 	DEVMETHOD(device_suspend,	spibus_suspend),
253 	DEVMETHOD(device_resume,	spibus_resume),
254 
255 	/* Bus interface */
256 	DEVMETHOD(bus_setup_intr,	bus_generic_setup_intr),
257 	DEVMETHOD(bus_teardown_intr,	bus_generic_teardown_intr),
258 	DEVMETHOD(bus_activate_resource, bus_generic_activate_resource),
259 	DEVMETHOD(bus_deactivate_resource, bus_generic_deactivate_resource),
260 	DEVMETHOD(bus_adjust_resource,	bus_generic_adjust_resource),
261 	DEVMETHOD(bus_alloc_resource,	bus_generic_rl_alloc_resource),
262 	DEVMETHOD(bus_release_resource,	bus_generic_rl_release_resource),
263 	DEVMETHOD(bus_get_resource,	bus_generic_rl_get_resource),
264 	DEVMETHOD(bus_set_resource,	bus_generic_rl_set_resource),
265 	DEVMETHOD(bus_get_resource_list, spibus_get_resource_list),
266 
267 	DEVMETHOD(bus_add_child,	spibus_add_child),
268 	DEVMETHOD(bus_print_child,	spibus_print_child),
269 	DEVMETHOD(bus_probe_nomatch,	spibus_probe_nomatch),
270 	DEVMETHOD(bus_read_ivar,	spibus_read_ivar),
271 	DEVMETHOD(bus_write_ivar,	spibus_write_ivar),
272 	DEVMETHOD(bus_child_location,	spibus_child_location),
273 	DEVMETHOD(bus_hinted_child,	spibus_hinted_child),
274 
275 	/* spibus interface */
276 	DEVMETHOD(spibus_transfer,	spibus_transfer_impl),
277 
278 	DEVMETHOD_END
279 };
280 
281 driver_t spibus_driver = {
282 	"spibus",
283 	spibus_methods,
284 	sizeof(struct spibus_softc)
285 };
286 
287 DRIVER_MODULE(spibus, spi, spibus_driver, 0, 0);
288 MODULE_VERSION(spibus, 1);
289