xref: /freebsd/sys/dev/iicbus/ofw_iicbus.c (revision 0d66206fff44f864ea8a4b220c3a53b4caa959a0)
1 /*-
2  * Copyright (c) 2009, Nathan Whitehorn <nwhitehorn@FreeBSD.org>
3  * All rights reserved.
4  *
5  * Redistribution and use in source and binary forms, with or without
6  * modification, are permitted provided that the following conditions
7  * are met:
8  * 1. Redistributions of source code must retain the above copyright
9  *    notice unmodified, this list of conditions, and the following
10  *    disclaimer.
11  * 2. Redistributions in binary form must reproduce the above copyright
12  *    notice, this list of conditions and the following disclaimer in the
13  *    documentation and/or other materials provided with the distribution.
14  *
15  * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
16  * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
17  * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
18  * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
19  * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
20  * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
21  * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
22  * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
23  * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
24  * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
25  */
26 
27 #include <sys/cdefs.h>
28 __FBSDID("$FreeBSD$");
29 
30 #include <sys/param.h>
31 #include <sys/bus.h>
32 #include <sys/kernel.h>
33 #include <sys/libkern.h>
34 #include <sys/lock.h>
35 #include <sys/module.h>
36 #include <sys/mutex.h>
37 
38 #include <dev/iicbus/iicbus.h>
39 #include <dev/iicbus/iiconf.h>
40 #include <dev/ofw/ofw_bus.h>
41 #include <dev/ofw/ofw_bus_subr.h>
42 #include <dev/ofw/openfirm.h>
43 
44 #include "iicbus_if.h"
45 #include "ofw_iicbus_if.h"
46 
47 /* Methods */
48 static device_probe_t ofw_iicbus_probe;
49 static device_attach_t ofw_iicbus_attach;
50 static device_t ofw_iicbus_add_child(device_t dev, u_int order,
51     const char *name, int unit);
52 static const struct ofw_bus_devinfo *ofw_iicbus_get_devinfo(device_t bus,
53     device_t dev);
54 static int ofw_iicbus_set_devinfo(device_t bus, device_t dev,
55     phandle_t ofw_node, char *ofw_name, char *ofw_compat, uint32_t i2c_addr);
56 
57 static device_method_t ofw_iicbus_methods[] = {
58 	/* Device interface */
59 	DEVMETHOD(device_probe,		ofw_iicbus_probe),
60 	DEVMETHOD(device_attach,	ofw_iicbus_attach),
61 
62 	/* Bus interface */
63 	DEVMETHOD(bus_child_pnpinfo,	ofw_bus_gen_child_pnpinfo),
64 	DEVMETHOD(bus_add_child,	ofw_iicbus_add_child),
65 
66 	/* ofw_bus interface */
67 	DEVMETHOD(ofw_bus_get_devinfo,	ofw_iicbus_get_devinfo),
68 	DEVMETHOD(ofw_bus_get_compat,	ofw_bus_gen_get_compat),
69 	DEVMETHOD(ofw_bus_get_model,	ofw_bus_gen_get_model),
70 	DEVMETHOD(ofw_bus_get_name,	ofw_bus_gen_get_name),
71 	DEVMETHOD(ofw_bus_get_node,	ofw_bus_gen_get_node),
72 	DEVMETHOD(ofw_bus_get_type,	ofw_bus_gen_get_type),
73 
74 	/* ofw_iicbus interface */
75 	DEVMETHOD(ofw_iicbus_set_devinfo, ofw_iicbus_set_devinfo),
76 
77 	DEVMETHOD_END
78 };
79 
80 struct ofw_iicbus_devinfo {
81 	struct iicbus_ivar	opd_dinfo;	/* Must be the first. */
82 	struct ofw_bus_devinfo	opd_obdinfo;
83 };
84 
85 DEFINE_CLASS_1(iicbus, ofw_iicbus_driver, ofw_iicbus_methods,
86     sizeof(struct iicbus_softc), iicbus_driver);
87 EARLY_DRIVER_MODULE(ofw_iicbus, iicbb, ofw_iicbus_driver, 0, 0, BUS_PASS_BUS);
88 EARLY_DRIVER_MODULE(ofw_iicbus, iichb, ofw_iicbus_driver, 0, 0, BUS_PASS_BUS);
89 EARLY_DRIVER_MODULE(ofw_iicbus, twsi, ofw_iicbus_driver, 0, 0, BUS_PASS_BUS);
90 MODULE_VERSION(ofw_iicbus, 1);
91 MODULE_DEPEND(ofw_iicbus, iicbus, 1, 1, 1);
92 
93 static int
94 ofw_iicbus_probe(device_t dev)
95 {
96 
97 	if (ofw_bus_get_node(dev) == -1)
98 		return (ENXIO);
99 	device_set_desc(dev, "OFW I2C bus");
100 
101 	return (0);
102 }
103 
104 static int
105 ofw_iicbus_attach(device_t dev)
106 {
107 	struct iicbus_softc *sc = IICBUS_SOFTC(dev);
108 	struct ofw_iicbus_devinfo *dinfo;
109 	phandle_t child, node, root;
110 	pcell_t freq, paddr;
111 	device_t childdev;
112 	ssize_t compatlen;
113 	char compat[255];
114 	char *curstr;
115 	u_int iic_addr_8bit = 0;
116 
117 	sc->dev = dev;
118 	mtx_init(&sc->lock, "iicbus", NULL, MTX_DEF);
119 
120 	/*
121 	 * If there is a clock-frequency property for the device node, use it as
122 	 * the starting value for the bus frequency.  Then call the common
123 	 * routine that handles the tunable/sysctl which allows the FDT value to
124 	 * be overridden by the user.
125 	 */
126 	node = ofw_bus_get_node(dev);
127 	freq = 0;
128 	OF_getencprop(node, "clock-frequency", &freq, sizeof(freq));
129 	iicbus_init_frequency(dev, freq);
130 
131 	iicbus_reset(dev, IIC_FASTEST, 0, NULL);
132 
133 	bus_generic_probe(dev);
134 	bus_enumerate_hinted_children(dev);
135 
136 	/*
137 	 * Check if we're running on a PowerMac, needed for the I2C
138 	 * address below.
139 	 */
140 	root = OF_peer(0);
141 	compatlen = OF_getprop(root, "compatible", compat,
142 				sizeof(compat));
143 	if (compatlen != -1) {
144 	    for (curstr = compat; curstr < compat + compatlen;
145 		curstr += strlen(curstr) + 1) {
146 		if (strncmp(curstr, "MacRISC", 7) == 0)
147 		    iic_addr_8bit = 1;
148 	    }
149 	}
150 
151 	/*
152 	 * Attach those children represented in the device tree.
153 	 */
154 	for (child = OF_child(node); child != 0; child = OF_peer(child)) {
155 		/*
156 		 * Try to get the I2C address first from the i2c-address
157 		 * property, then try the reg property.  It moves around
158 		 * on different systems.
159 		 */
160 		if (OF_getencprop(child, "i2c-address", &paddr,
161 		    sizeof(paddr)) == -1)
162 			if (OF_getencprop(child, "reg", &paddr,
163 			    sizeof(paddr)) == -1)
164 				continue;
165 
166 		/*
167 		 * Now set up the I2C and OFW bus layer devinfo and add it
168 		 * to the bus.
169 		 */
170 		dinfo = malloc(sizeof(struct ofw_iicbus_devinfo), M_DEVBUF,
171 		    M_NOWAIT | M_ZERO);
172 		if (dinfo == NULL)
173 			continue;
174 		/*
175 		 * FreeBSD drivers expect I2C addresses to be expressed as
176 		 * 8-bit values.  Apple OFW data contains 8-bit values, but
177 		 * Linux FDT data contains 7-bit values, so shift them up to
178 		 * 8-bit format.
179 		 */
180 		if (iic_addr_8bit)
181 		    dinfo->opd_dinfo.addr = paddr;
182 		else
183 		    dinfo->opd_dinfo.addr = paddr << 1;
184 
185 		if (ofw_bus_gen_setup_devinfo(&dinfo->opd_obdinfo, child) !=
186 		    0) {
187 			free(dinfo, M_DEVBUF);
188 			continue;
189 		}
190 
191 		childdev = device_add_child(dev, NULL, -1);
192 		resource_list_init(&dinfo->opd_dinfo.rl);
193 		ofw_bus_intr_to_rl(childdev, child,
194 					&dinfo->opd_dinfo.rl, NULL);
195 		device_set_ivars(childdev, dinfo);
196 	}
197 
198 	/* Register bus */
199 	OF_device_register_xref(OF_xref_from_node(node), dev);
200 	return (bus_generic_attach(dev));
201 }
202 
203 static device_t
204 ofw_iicbus_add_child(device_t dev, u_int order, const char *name, int unit)
205 {
206 	device_t child;
207 	struct ofw_iicbus_devinfo *devi;
208 
209 	child = device_add_child_ordered(dev, order, name, unit);
210 	if (child == NULL)
211 		return (child);
212 	devi = malloc(sizeof(struct ofw_iicbus_devinfo), M_DEVBUF,
213 	    M_NOWAIT | M_ZERO);
214 	if (devi == NULL) {
215 		device_delete_child(dev, child);
216 		return (0);
217 	}
218 
219 	/*
220 	 * NULL all the OFW-related parts of the ivars for non-OFW
221 	 * children.
222 	 */
223 	devi->opd_obdinfo.obd_node = -1;
224 	devi->opd_obdinfo.obd_name = NULL;
225 	devi->opd_obdinfo.obd_compat = NULL;
226 	devi->opd_obdinfo.obd_type = NULL;
227 	devi->opd_obdinfo.obd_model = NULL;
228 
229 	device_set_ivars(child, devi);
230 
231 	return (child);
232 }
233 
234 static const struct ofw_bus_devinfo *
235 ofw_iicbus_get_devinfo(device_t bus, device_t dev)
236 {
237 	struct ofw_iicbus_devinfo *dinfo;
238 
239 	dinfo = device_get_ivars(dev);
240 	return (&dinfo->opd_obdinfo);
241 }
242 
243 static int
244 ofw_iicbus_set_devinfo(device_t bus, device_t dev, phandle_t ofw_node,
245     char *ofw_name, char *ofw_compat, uint32_t i2c_addr)
246 {
247 	struct ofw_iicbus_devinfo *devi;
248 
249 	/*
250 	 * Setup OFW-related parts of the ivars for manually
251 	 * created ofw_iicbus childern.
252 	 */
253 	devi = device_get_ivars(dev);
254 	if (devi == NULL)
255 		return (ENXIO);
256 
257 	devi->opd_obdinfo.obd_node = ofw_node;
258 	if (ofw_name != NULL)
259 		devi->opd_obdinfo.obd_name = strdup(ofw_name, M_OFWPROP);
260 	if (ofw_compat != NULL)
261 		devi->opd_obdinfo.obd_compat = strdup(ofw_compat, M_OFWPROP);
262 	devi->opd_dinfo.addr = i2c_addr;
263 	return (0);
264 }
265