xref: /freebsd/sys/dev/spibus/spibus.c (revision 685dc743dc3b5645e34836464128e1c0558b404b)
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 #include <sys/param.h>
29 #include <sys/systm.h>
30 #include <sys/malloc.h>
31 #include <sys/module.h>
32 #include <sys/kernel.h>
33 #include <sys/queue.h>
34 #include <sys/sbuf.h>
35 #include <sys/sysctl.h>
36 
37 #include <sys/bus.h>
38 #include <machine/bus.h>
39 #include <sys/rman.h>
40 #include <machine/resource.h>
41 
42 #include <dev/spibus/spibusvar.h>
43 #include <dev/spibus/spi.h>
44 #include "spibus_if.h"
45 
46 static int
47 spibus_probe(device_t dev)
48 {
49 
50 	device_set_desc(dev, "SPI bus");
51 	return (BUS_PROBE_DEFAULT);
52 }
53 
54 int
55 spibus_attach(device_t dev)
56 {
57 	struct spibus_softc *sc = SPIBUS_SOFTC(dev);
58 
59 	sc->dev = dev;
60 	bus_enumerate_hinted_children(dev);
61 	return (bus_generic_attach(dev));
62 }
63 
64 /*
65  * Since this is not a self-enumerating bus, and since we always add
66  * children in attach, we have to always delete children here.
67  */
68 int
69 spibus_detach(device_t dev)
70 {
71 	return (device_delete_children(dev));
72 }
73 
74 static int
75 spibus_suspend(device_t dev)
76 {
77 	return (bus_generic_suspend(dev));
78 }
79 
80 static
81 int
82 spibus_resume(device_t dev)
83 {
84 	return (bus_generic_resume(dev));
85 }
86 
87 static int
88 spibus_print_child(device_t dev, device_t child)
89 {
90 	struct spibus_ivar *devi = SPIBUS_IVAR(child);
91 	int retval = 0;
92 
93 	retval += bus_print_child_header(dev, child);
94 	retval += printf(" at cs %d", devi->cs);
95 	retval += printf(" mode %d", devi->mode);
96 	retval += resource_list_print_type(&devi->rl, "irq",
97 	    SYS_RES_IRQ, "%jd");
98 	retval += bus_print_child_footer(dev, child);
99 
100 	return (retval);
101 }
102 
103 void
104 spibus_probe_nomatch(device_t bus, device_t child)
105 {
106 	struct spibus_ivar *devi = SPIBUS_IVAR(child);
107 
108 	device_printf(bus, "<unknown card> at cs %d mode %d\n", devi->cs,
109 	    devi->mode);
110 	return;
111 }
112 
113 int
114 spibus_child_location(device_t bus, device_t child, struct sbuf *sb)
115 {
116 	struct spibus_ivar *devi = SPIBUS_IVAR(child);
117 	int cs;
118 
119 	cs = devi->cs & ~SPIBUS_CS_HIGH; /* trim 'cs high' bit */
120 	sbuf_printf(sb, "bus=%d cs=%d", device_get_unit(bus), cs);
121 	return (0);
122 }
123 
124 int
125 spibus_read_ivar(device_t bus, device_t child, int which, uintptr_t *result)
126 {
127 	struct spibus_ivar *devi = SPIBUS_IVAR(child);
128 
129 	switch (which) {
130 	default:
131 		return (EINVAL);
132 	case SPIBUS_IVAR_CS:
133 		*(uint32_t *)result = devi->cs;
134 		break;
135 	case SPIBUS_IVAR_MODE:
136 		*(uint32_t *)result = devi->mode;
137 		break;
138 	case SPIBUS_IVAR_CLOCK:
139 		*(uint32_t *)result = devi->clock;
140 		break;
141 	case SPIBUS_IVAR_CS_DELAY:
142 		*(uint32_t *)result = devi->cs_delay;
143 		break;
144 	}
145 	return (0);
146 }
147 
148 int
149 spibus_write_ivar(device_t bus, device_t child, int which, uintptr_t value)
150 {
151 	struct spibus_ivar *devi = SPIBUS_IVAR(child);
152 
153 	if (devi == NULL || device_get_parent(child) != bus)
154 		return (EDOOFUS);
155 
156 	switch (which) {
157 	case SPIBUS_IVAR_CLOCK:
158 		/* Any non-zero value is allowed for max clock frequency. */
159 		if (value == 0)
160 			return (EINVAL);
161 		devi->clock = (uint32_t)value;
162 		break;
163 	case SPIBUS_IVAR_CS:
164 		 /* Chip select cannot be changed. */
165 		return (EINVAL);
166 	case SPIBUS_IVAR_MODE:
167 		/* Valid SPI modes are 0-3. */
168 		if (value > 3)
169 			return (EINVAL);
170 		devi->mode = (uint32_t)value;
171 		break;
172 	case SPIBUS_IVAR_CS_DELAY:
173 		devi->cs_delay = (uint32_t)value;
174 		break;
175 	default:
176 		return (EINVAL);
177 	}
178 
179 	return (0);
180 }
181 
182 device_t
183 spibus_add_child_common(device_t dev, u_int order, const char *name, int unit,
184     size_t ivars_size)
185 {
186 	device_t child;
187 	struct spibus_ivar *devi;
188 
189 	child = device_add_child_ordered(dev, order, name, unit);
190 	if (child == NULL)
191 		return (child);
192 	devi = malloc(ivars_size, M_DEVBUF, M_NOWAIT | M_ZERO);
193 	if (devi == NULL) {
194 		device_delete_child(dev, child);
195 		return (0);
196 	}
197 	resource_list_init(&devi->rl);
198 	device_set_ivars(child, devi);
199 	return (child);
200 }
201 
202 static device_t
203 spibus_add_child(device_t dev, u_int order, const char *name, int unit)
204 {
205 	return (spibus_add_child_common(
206 	    dev, order, name, unit, sizeof(struct spibus_ivar)));
207 }
208 
209 static void
210 spibus_hinted_child(device_t bus, const char *dname, int dunit)
211 {
212 	device_t child;
213 	int irq;
214 	struct spibus_ivar *devi;
215 
216 	child = BUS_ADD_CHILD(bus, 0, dname, dunit);
217 	devi = SPIBUS_IVAR(child);
218 	devi->mode = SPIBUS_MODE_NONE;
219 	resource_int_value(dname, dunit, "clock", &devi->clock);
220 	resource_int_value(dname, dunit, "cs", &devi->cs);
221 	resource_int_value(dname, dunit, "mode", &devi->mode);
222 	if (resource_int_value(dname, dunit, "irq", &irq) == 0) {
223 		if (bus_set_resource(child, SYS_RES_IRQ, 0, irq, 1) != 0)
224 			device_printf(bus,
225 			    "Warning: bus_set_resource() failed\n");
226 	}
227 }
228 
229 static struct resource_list *
230 spibus_get_resource_list(device_t bus __unused, device_t child)
231 {
232 	struct spibus_ivar *devi;
233 
234 	devi = SPIBUS_IVAR(child);
235 	return (&devi->rl);
236 }
237 
238 static int
239 spibus_transfer_impl(device_t dev, device_t child, struct spi_command *cmd)
240 {
241 	return (SPIBUS_TRANSFER(device_get_parent(dev), child, cmd));
242 }
243 
244 static device_method_t spibus_methods[] = {
245 	/* Device interface */
246 	DEVMETHOD(device_probe,		spibus_probe),
247 	DEVMETHOD(device_attach,	spibus_attach),
248 	DEVMETHOD(device_detach,	spibus_detach),
249 	DEVMETHOD(device_shutdown,	bus_generic_shutdown),
250 	DEVMETHOD(device_suspend,	spibus_suspend),
251 	DEVMETHOD(device_resume,	spibus_resume),
252 
253 	/* Bus interface */
254 	DEVMETHOD(bus_setup_intr,	bus_generic_setup_intr),
255 	DEVMETHOD(bus_teardown_intr,	bus_generic_teardown_intr),
256 	DEVMETHOD(bus_activate_resource, bus_generic_activate_resource),
257 	DEVMETHOD(bus_deactivate_resource, bus_generic_deactivate_resource),
258 	DEVMETHOD(bus_adjust_resource,	bus_generic_adjust_resource),
259 	DEVMETHOD(bus_alloc_resource,	bus_generic_rl_alloc_resource),
260 	DEVMETHOD(bus_release_resource,	bus_generic_rl_release_resource),
261 	DEVMETHOD(bus_get_resource,	bus_generic_rl_get_resource),
262 	DEVMETHOD(bus_set_resource,	bus_generic_rl_set_resource),
263 	DEVMETHOD(bus_get_resource_list, spibus_get_resource_list),
264 
265 	DEVMETHOD(bus_add_child,	spibus_add_child),
266 	DEVMETHOD(bus_print_child,	spibus_print_child),
267 	DEVMETHOD(bus_probe_nomatch,	spibus_probe_nomatch),
268 	DEVMETHOD(bus_read_ivar,	spibus_read_ivar),
269 	DEVMETHOD(bus_write_ivar,	spibus_write_ivar),
270 	DEVMETHOD(bus_child_location,	spibus_child_location),
271 	DEVMETHOD(bus_hinted_child,	spibus_hinted_child),
272 
273 	/* spibus interface */
274 	DEVMETHOD(spibus_transfer,	spibus_transfer_impl),
275 
276 	DEVMETHOD_END
277 };
278 
279 driver_t spibus_driver = {
280 	"spibus",
281 	spibus_methods,
282 	sizeof(struct spibus_softc)
283 };
284 
285 DRIVER_MODULE(spibus, spi, spibus_driver, 0, 0);
286 MODULE_VERSION(spibus, 1);
287