xref: /freebsd/sys/dev/spibus/spibus.c (revision 5ca8e32633c4ffbbcd6762e5888b6a4ba0708c6c)
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/param.h>
28 #include <sys/systm.h>
29 #include <sys/malloc.h>
30 #include <sys/module.h>
31 #include <sys/kernel.h>
32 #include <sys/queue.h>
33 #include <sys/sbuf.h>
34 #include <sys/sysctl.h>
35 
36 #include <sys/bus.h>
37 #include <machine/bus.h>
38 #include <sys/rman.h>
39 #include <machine/resource.h>
40 
41 #include <dev/spibus/spibusvar.h>
42 #include <dev/spibus/spi.h>
43 #include "spibus_if.h"
44 
45 static int
46 spibus_probe(device_t dev)
47 {
48 
49 	device_set_desc(dev, "SPI bus");
50 	return (BUS_PROBE_DEFAULT);
51 }
52 
53 int
54 spibus_attach(device_t dev)
55 {
56 	struct spibus_softc *sc = SPIBUS_SOFTC(dev);
57 
58 	sc->dev = dev;
59 	bus_enumerate_hinted_children(dev);
60 	return (bus_generic_attach(dev));
61 }
62 
63 /*
64  * Since this is not a self-enumerating bus, and since we always add
65  * children in attach, we have to always delete children here.
66  */
67 int
68 spibus_detach(device_t dev)
69 {
70 	return (device_delete_children(dev));
71 }
72 
73 static int
74 spibus_suspend(device_t dev)
75 {
76 	return (bus_generic_suspend(dev));
77 }
78 
79 static
80 int
81 spibus_resume(device_t dev)
82 {
83 	return (bus_generic_resume(dev));
84 }
85 
86 static int
87 spibus_print_child(device_t dev, device_t child)
88 {
89 	struct spibus_ivar *devi = SPIBUS_IVAR(child);
90 	int retval = 0;
91 
92 	retval += bus_print_child_header(dev, child);
93 	retval += printf(" at cs %d", devi->cs);
94 	retval += printf(" mode %d", devi->mode);
95 	retval += resource_list_print_type(&devi->rl, "irq",
96 	    SYS_RES_IRQ, "%jd");
97 	retval += bus_print_child_footer(dev, child);
98 
99 	return (retval);
100 }
101 
102 void
103 spibus_probe_nomatch(device_t bus, device_t child)
104 {
105 	struct spibus_ivar *devi = SPIBUS_IVAR(child);
106 
107 	device_printf(bus, "<unknown card> at cs %d mode %d\n", devi->cs,
108 	    devi->mode);
109 	return;
110 }
111 
112 int
113 spibus_child_location(device_t bus, device_t child, struct sbuf *sb)
114 {
115 	struct spibus_ivar *devi = SPIBUS_IVAR(child);
116 	int cs;
117 
118 	cs = devi->cs & ~SPIBUS_CS_HIGH; /* trim 'cs high' bit */
119 	sbuf_printf(sb, "bus=%d cs=%d", device_get_unit(bus), cs);
120 	return (0);
121 }
122 
123 int
124 spibus_read_ivar(device_t bus, device_t child, int which, uintptr_t *result)
125 {
126 	struct spibus_ivar *devi = SPIBUS_IVAR(child);
127 
128 	switch (which) {
129 	default:
130 		return (EINVAL);
131 	case SPIBUS_IVAR_CS:
132 		*(uint32_t *)result = devi->cs;
133 		break;
134 	case SPIBUS_IVAR_MODE:
135 		*(uint32_t *)result = devi->mode;
136 		break;
137 	case SPIBUS_IVAR_CLOCK:
138 		*(uint32_t *)result = devi->clock;
139 		break;
140 	case SPIBUS_IVAR_CS_DELAY:
141 		*(uint32_t *)result = devi->cs_delay;
142 		break;
143 	}
144 	return (0);
145 }
146 
147 int
148 spibus_write_ivar(device_t bus, device_t child, int which, uintptr_t value)
149 {
150 	struct spibus_ivar *devi = SPIBUS_IVAR(child);
151 
152 	if (devi == NULL || device_get_parent(child) != bus)
153 		return (EDOOFUS);
154 
155 	switch (which) {
156 	case SPIBUS_IVAR_CLOCK:
157 		/* Any non-zero value is allowed for max clock frequency. */
158 		if (value == 0)
159 			return (EINVAL);
160 		devi->clock = (uint32_t)value;
161 		break;
162 	case SPIBUS_IVAR_CS:
163 		 /* Chip select cannot be changed. */
164 		return (EINVAL);
165 	case SPIBUS_IVAR_MODE:
166 		/* Valid SPI modes are 0-3. */
167 		if (value > 3)
168 			return (EINVAL);
169 		devi->mode = (uint32_t)value;
170 		break;
171 	case SPIBUS_IVAR_CS_DELAY:
172 		devi->cs_delay = (uint32_t)value;
173 		break;
174 	default:
175 		return (EINVAL);
176 	}
177 
178 	return (0);
179 }
180 
181 device_t
182 spibus_add_child_common(device_t dev, u_int order, const char *name, int unit,
183     size_t ivars_size)
184 {
185 	device_t child;
186 	struct spibus_ivar *devi;
187 
188 	child = device_add_child_ordered(dev, order, name, unit);
189 	if (child == NULL)
190 		return (child);
191 	devi = malloc(ivars_size, M_DEVBUF, M_NOWAIT | M_ZERO);
192 	if (devi == NULL) {
193 		device_delete_child(dev, child);
194 		return (0);
195 	}
196 	resource_list_init(&devi->rl);
197 	device_set_ivars(child, devi);
198 	return (child);
199 }
200 
201 static device_t
202 spibus_add_child(device_t dev, u_int order, const char *name, int unit)
203 {
204 	return (spibus_add_child_common(
205 	    dev, order, name, unit, sizeof(struct spibus_ivar)));
206 }
207 
208 static void
209 spibus_hinted_child(device_t bus, const char *dname, int dunit)
210 {
211 	device_t child;
212 	int irq;
213 	struct spibus_ivar *devi;
214 
215 	child = BUS_ADD_CHILD(bus, 0, dname, dunit);
216 	devi = SPIBUS_IVAR(child);
217 	devi->mode = SPIBUS_MODE_NONE;
218 	resource_int_value(dname, dunit, "clock", &devi->clock);
219 	resource_int_value(dname, dunit, "cs", &devi->cs);
220 	resource_int_value(dname, dunit, "mode", &devi->mode);
221 	if (resource_int_value(dname, dunit, "irq", &irq) == 0) {
222 		if (bus_set_resource(child, SYS_RES_IRQ, 0, irq, 1) != 0)
223 			device_printf(bus,
224 			    "Warning: bus_set_resource() failed\n");
225 	}
226 }
227 
228 static struct resource_list *
229 spibus_get_resource_list(device_t bus __unused, device_t child)
230 {
231 	struct spibus_ivar *devi;
232 
233 	devi = SPIBUS_IVAR(child);
234 	return (&devi->rl);
235 }
236 
237 static int
238 spibus_transfer_impl(device_t dev, device_t child, struct spi_command *cmd)
239 {
240 	return (SPIBUS_TRANSFER(device_get_parent(dev), child, cmd));
241 }
242 
243 static device_method_t spibus_methods[] = {
244 	/* Device interface */
245 	DEVMETHOD(device_probe,		spibus_probe),
246 	DEVMETHOD(device_attach,	spibus_attach),
247 	DEVMETHOD(device_detach,	spibus_detach),
248 	DEVMETHOD(device_shutdown,	bus_generic_shutdown),
249 	DEVMETHOD(device_suspend,	spibus_suspend),
250 	DEVMETHOD(device_resume,	spibus_resume),
251 
252 	/* Bus interface */
253 	DEVMETHOD(bus_setup_intr,	bus_generic_setup_intr),
254 	DEVMETHOD(bus_teardown_intr,	bus_generic_teardown_intr),
255 	DEVMETHOD(bus_activate_resource, bus_generic_activate_resource),
256 	DEVMETHOD(bus_deactivate_resource, bus_generic_deactivate_resource),
257 	DEVMETHOD(bus_adjust_resource,	bus_generic_adjust_resource),
258 	DEVMETHOD(bus_alloc_resource,	bus_generic_rl_alloc_resource),
259 	DEVMETHOD(bus_release_resource,	bus_generic_rl_release_resource),
260 	DEVMETHOD(bus_get_resource,	bus_generic_rl_get_resource),
261 	DEVMETHOD(bus_set_resource,	bus_generic_rl_set_resource),
262 	DEVMETHOD(bus_get_resource_list, spibus_get_resource_list),
263 
264 	DEVMETHOD(bus_add_child,	spibus_add_child),
265 	DEVMETHOD(bus_print_child,	spibus_print_child),
266 	DEVMETHOD(bus_probe_nomatch,	spibus_probe_nomatch),
267 	DEVMETHOD(bus_read_ivar,	spibus_read_ivar),
268 	DEVMETHOD(bus_write_ivar,	spibus_write_ivar),
269 	DEVMETHOD(bus_child_location,	spibus_child_location),
270 	DEVMETHOD(bus_hinted_child,	spibus_hinted_child),
271 
272 	/* spibus interface */
273 	DEVMETHOD(spibus_transfer,	spibus_transfer_impl),
274 
275 	DEVMETHOD_END
276 };
277 
278 driver_t spibus_driver = {
279 	"spibus",
280 	spibus_methods,
281 	sizeof(struct spibus_softc)
282 };
283 
284 DRIVER_MODULE(spibus, spi, spibus_driver, 0, 0);
285 MODULE_VERSION(spibus, 1);
286