xref: /freebsd/sys/dev/spibus/spibus.c (revision dd21556857e8d40f66bf5ad54754d9d52669ebf7)
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 	bus_attach_children(dev);
61 	return (0);
62 }
63 
64 static int
65 spibus_print_child(device_t dev, device_t child)
66 {
67 	struct spibus_ivar *devi = SPIBUS_IVAR(child);
68 	int retval = 0;
69 
70 	retval += bus_print_child_header(dev, child);
71 	retval += printf(" at cs %d", devi->cs);
72 	retval += printf(" mode %d", devi->mode);
73 	retval += resource_list_print_type(&devi->rl, "irq",
74 	    SYS_RES_IRQ, "%jd");
75 	retval += bus_print_child_footer(dev, child);
76 
77 	return (retval);
78 }
79 
80 void
81 spibus_probe_nomatch(device_t bus, device_t child)
82 {
83 	struct spibus_ivar *devi = SPIBUS_IVAR(child);
84 
85 	device_printf(bus, "<unknown card> at cs %d mode %d\n", devi->cs,
86 	    devi->mode);
87 	return;
88 }
89 
90 int
91 spibus_child_location(device_t bus, device_t child, struct sbuf *sb)
92 {
93 	struct spibus_ivar *devi = SPIBUS_IVAR(child);
94 	int cs;
95 
96 	cs = devi->cs & ~SPIBUS_CS_HIGH; /* trim 'cs high' bit */
97 	sbuf_printf(sb, "bus=%d cs=%d", device_get_unit(bus), cs);
98 	return (0);
99 }
100 
101 int
102 spibus_read_ivar(device_t bus, device_t child, int which, uintptr_t *result)
103 {
104 	struct spibus_ivar *devi = SPIBUS_IVAR(child);
105 
106 	switch (which) {
107 	default:
108 		return (EINVAL);
109 	case SPIBUS_IVAR_CS:
110 		*(uint32_t *)result = devi->cs;
111 		break;
112 	case SPIBUS_IVAR_MODE:
113 		*(uint32_t *)result = devi->mode;
114 		break;
115 	case SPIBUS_IVAR_CLOCK:
116 		*(uint32_t *)result = devi->clock;
117 		break;
118 	case SPIBUS_IVAR_CS_DELAY:
119 		*(uint32_t *)result = devi->cs_delay;
120 		break;
121 	}
122 	return (0);
123 }
124 
125 int
126 spibus_write_ivar(device_t bus, device_t child, int which, uintptr_t value)
127 {
128 	struct spibus_ivar *devi = SPIBUS_IVAR(child);
129 
130 	if (devi == NULL || device_get_parent(child) != bus)
131 		return (EDOOFUS);
132 
133 	switch (which) {
134 	case SPIBUS_IVAR_CLOCK:
135 		/* Any non-zero value is allowed for max clock frequency. */
136 		if (value == 0)
137 			return (EINVAL);
138 		devi->clock = (uint32_t)value;
139 		break;
140 	case SPIBUS_IVAR_CS:
141 		 /* Chip select cannot be changed. */
142 		return (EINVAL);
143 	case SPIBUS_IVAR_MODE:
144 		/* Valid SPI modes are 0-3. */
145 		if (value > 3)
146 			return (EINVAL);
147 		devi->mode = (uint32_t)value;
148 		break;
149 	case SPIBUS_IVAR_CS_DELAY:
150 		devi->cs_delay = (uint32_t)value;
151 		break;
152 	default:
153 		return (EINVAL);
154 	}
155 
156 	return (0);
157 }
158 
159 device_t
160 spibus_add_child_common(device_t dev, u_int order, const char *name, int unit,
161     size_t ivars_size)
162 {
163 	device_t child;
164 	struct spibus_ivar *devi;
165 
166 	child = device_add_child_ordered(dev, order, name, unit);
167 	if (child == NULL)
168 		return (child);
169 	devi = malloc(ivars_size, M_DEVBUF, M_NOWAIT | M_ZERO);
170 	if (devi == NULL) {
171 		device_delete_child(dev, child);
172 		return (0);
173 	}
174 	resource_list_init(&devi->rl);
175 	device_set_ivars(child, devi);
176 	return (child);
177 }
178 
179 void
180 spibus_child_deleted(device_t dev, device_t child)
181 {
182 	struct spibus_ivar *devi;
183 
184 	devi = device_get_ivars(child);
185 	if (devi == NULL)
186 		return;
187 	resource_list_free(&devi->rl);
188 	free(devi, M_DEVBUF);
189 }
190 
191 static device_t
192 spibus_add_child(device_t dev, u_int order, const char *name, int unit)
193 {
194 	return (spibus_add_child_common(
195 	    dev, order, name, unit, sizeof(struct spibus_ivar)));
196 }
197 
198 static void
199 spibus_hinted_child(device_t bus, const char *dname, int dunit)
200 {
201 	device_t child;
202 	int irq;
203 	struct spibus_ivar *devi;
204 
205 	child = BUS_ADD_CHILD(bus, 0, dname, dunit);
206 	devi = SPIBUS_IVAR(child);
207 	devi->mode = SPIBUS_MODE_NONE;
208 	resource_int_value(dname, dunit, "clock", &devi->clock);
209 	resource_int_value(dname, dunit, "cs", &devi->cs);
210 	resource_int_value(dname, dunit, "mode", &devi->mode);
211 	if (resource_int_value(dname, dunit, "irq", &irq) == 0) {
212 		if (bus_set_resource(child, SYS_RES_IRQ, 0, irq, 1) != 0)
213 			device_printf(bus,
214 			    "Warning: bus_set_resource() failed\n");
215 	}
216 }
217 
218 static struct resource_list *
219 spibus_get_resource_list(device_t bus __unused, device_t child)
220 {
221 	struct spibus_ivar *devi;
222 
223 	devi = SPIBUS_IVAR(child);
224 	return (&devi->rl);
225 }
226 
227 static int
228 spibus_transfer_impl(device_t dev, device_t child, struct spi_command *cmd)
229 {
230 	return (SPIBUS_TRANSFER(device_get_parent(dev), child, cmd));
231 }
232 
233 static device_method_t spibus_methods[] = {
234 	/* Device interface */
235 	DEVMETHOD(device_probe,		spibus_probe),
236 	DEVMETHOD(device_attach,	spibus_attach),
237 	DEVMETHOD(device_detach,	bus_generic_detach),
238 	DEVMETHOD(device_shutdown,	bus_generic_shutdown),
239 	DEVMETHOD(device_suspend,	bus_generic_suspend),
240 	DEVMETHOD(device_resume,	bus_generic_resume),
241 
242 	/* Bus interface */
243 	DEVMETHOD(bus_setup_intr,	bus_generic_setup_intr),
244 	DEVMETHOD(bus_teardown_intr,	bus_generic_teardown_intr),
245 	DEVMETHOD(bus_activate_resource, bus_generic_activate_resource),
246 	DEVMETHOD(bus_deactivate_resource, bus_generic_deactivate_resource),
247 	DEVMETHOD(bus_adjust_resource,	bus_generic_adjust_resource),
248 	DEVMETHOD(bus_alloc_resource,	bus_generic_rl_alloc_resource),
249 	DEVMETHOD(bus_release_resource,	bus_generic_rl_release_resource),
250 	DEVMETHOD(bus_get_resource,	bus_generic_rl_get_resource),
251 	DEVMETHOD(bus_set_resource,	bus_generic_rl_set_resource),
252 	DEVMETHOD(bus_get_resource_list, spibus_get_resource_list),
253 
254 	DEVMETHOD(bus_add_child,	spibus_add_child),
255 	DEVMETHOD(bus_child_deleted,	spibus_child_deleted),
256 	DEVMETHOD(bus_print_child,	spibus_print_child),
257 	DEVMETHOD(bus_probe_nomatch,	spibus_probe_nomatch),
258 	DEVMETHOD(bus_read_ivar,	spibus_read_ivar),
259 	DEVMETHOD(bus_write_ivar,	spibus_write_ivar),
260 	DEVMETHOD(bus_child_location,	spibus_child_location),
261 	DEVMETHOD(bus_hinted_child,	spibus_hinted_child),
262 
263 	/* spibus interface */
264 	DEVMETHOD(spibus_transfer,	spibus_transfer_impl),
265 
266 	DEVMETHOD_END
267 };
268 
269 driver_t spibus_driver = {
270 	"spibus",
271 	spibus_methods,
272 	sizeof(struct spibus_softc)
273 };
274 
275 DRIVER_MODULE(spibus, spi, spibus_driver, 0, 0);
276 MODULE_VERSION(spibus, 1);
277