xref: /netbsd-src/sys/dev/fdt/fdt_pinctrl.c (revision bdc22b2e01993381dcefeff2bc9b56ca75a4235c)
1 /* $NetBSD: fdt_pinctrl.c,v 1.5 2018/06/30 20:34:43 jmcneill Exp $ */
2 
3 /*-
4  * Copyright (c) 2017 Jared McNeill <jmcneill@invisible.ca>
5  * Copyright (c) 2015 Martin Fouts
6  * All rights reserved.
7  *
8  * Redistribution and use in source and binary forms, with or without
9  * modification, are permitted provided that the following conditions
10  * are met:
11  * 1. Redistributions of source code must retain the above copyright
12  *    notice, this list of conditions and the following disclaimer.
13  * 2. Redistributions in binary form must reproduce the above copyright
14  *    notice, this list of conditions and the following disclaimer in the
15  *    documentation and/or other materials provided with the distribution.
16  *
17  * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
18  * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
19  * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
20  * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
21  * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING,
22  * BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
23  * LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED
24  * AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY,
25  * OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
26  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
27  * SUCH DAMAGE.
28  */
29 
30 #include <sys/cdefs.h>
31 __KERNEL_RCSID(0, "$NetBSD: fdt_pinctrl.c,v 1.5 2018/06/30 20:34:43 jmcneill Exp $");
32 
33 #include <sys/param.h>
34 #include <sys/bus.h>
35 #include <sys/kmem.h>
36 #include <sys/queue.h>
37 
38 #include <libfdt.h>
39 #include <dev/fdt/fdtvar.h>
40 
41 struct fdtbus_pinctrl_controller {
42 	device_t pc_dev;
43 	int pc_phandle;
44 	const struct fdtbus_pinctrl_controller_func *pc_funcs;
45 
46 	LIST_ENTRY(fdtbus_pinctrl_controller) pc_next;
47 };
48 
49 static LIST_HEAD(, fdtbus_pinctrl_controller) fdtbus_pinctrl_controllers =
50     LIST_HEAD_INITIALIZER(fdtbus_pinctrl_controllers);
51 
52 int
53 fdtbus_register_pinctrl_config(device_t dev, int phandle,
54     const struct fdtbus_pinctrl_controller_func *funcs)
55 {
56 	struct fdtbus_pinctrl_controller *pc;
57 
58 	pc = kmem_alloc(sizeof(*pc), KM_SLEEP);
59 	pc->pc_dev = dev;
60 	pc->pc_phandle = phandle;
61 	pc->pc_funcs = funcs;
62 
63 	LIST_INSERT_HEAD(&fdtbus_pinctrl_controllers, pc, pc_next);
64 
65 	return 0;
66 }
67 
68 static struct fdtbus_pinctrl_controller *
69 fdtbus_pinctrl_lookup(int phandle)
70 {
71 	struct fdtbus_pinctrl_controller *pc;
72 
73 	LIST_FOREACH(pc, &fdtbus_pinctrl_controllers, pc_next) {
74 		if (pc->pc_phandle == phandle)
75 			return pc;
76 	}
77 
78 	return NULL;
79 }
80 
81 int
82 fdtbus_pinctrl_set_config_index(int phandle, u_int index)
83 {
84 	struct fdtbus_pinctrl_controller *pc;
85 	const u_int *pinctrl_data;
86 	char buf[16];
87 	u_int xref, pinctrl_cells;
88 	int len, error;
89 
90 	snprintf(buf, sizeof(buf), "pinctrl-%u", index);
91 
92 	pinctrl_data = fdtbus_get_prop(phandle, buf, &len);
93 	if (pinctrl_data == NULL)
94 		return ENOENT;
95 
96 	while (len > 0) {
97 		xref = fdtbus_get_phandle_from_native(be32toh(pinctrl_data[0]));
98 		pc = fdtbus_pinctrl_lookup(xref);
99 		if (pc == NULL)
100 			return ENXIO;
101 
102 		if (of_getprop_uint32(OF_parent(xref), "#pinctrl-cells", &pinctrl_cells) != 0)
103 			pinctrl_cells = 1;
104 
105 		error = pc->pc_funcs->set_config(pc->pc_dev, pinctrl_data, pinctrl_cells * 4);
106 		if (error != 0)
107 			return error;
108 
109 		pinctrl_data += pinctrl_cells;
110 		len -= (pinctrl_cells * 4);
111 	}
112 
113 	return 0;
114 }
115 
116 int
117 fdtbus_pinctrl_set_config(int phandle, const char *cfgname)
118 {
119 	const char *pinctrl_names, *name;
120 	int len, index;
121 
122 	if ((len = OF_getproplen(phandle, "pinctrl-names")) < 0)
123 		return -1;
124 
125 	pinctrl_names = fdtbus_get_string(phandle, "pinctrl-names");
126 
127 	for (name = pinctrl_names, index = 0; len > 0;
128 	     name += strlen(name) + 1, index++) {
129 		if (strcmp(name, cfgname) == 0)
130 			return fdtbus_pinctrl_set_config_index(phandle, index);
131 	}
132 
133 	/* Not found */
134 	return -1;
135 }
136 
137 static void
138 fdtbus_pinctrl_configure_node(int phandle)
139 {
140 	char buf[256];
141 	int child, error;
142 
143 	for (child = OF_child(phandle); child; child = OF_peer(child)) {
144 		if (!fdtbus_status_okay(child))
145 			continue;
146 
147 		/* Configure child nodes */
148 		fdtbus_pinctrl_configure_node(child);
149 
150 		/*
151 		 * Set configuration 0 for this node. This may fail if the
152 		 * pinctrl provider is missing; that's OK, we will re-configure
153 		 * when that provider attaches.
154 		 */
155 		fdtbus_get_path(child, buf, sizeof(buf));
156 		error = fdtbus_pinctrl_set_config_index(child, 0);
157 		if (error == 0)
158 			aprint_debug("pinctrl: set config pinctrl-0 for %s\n", buf);
159 		else if (error != ENOENT)
160 			aprint_debug("pinctrl: failed to set config pinctrl-0 for %s: %d\n", buf, error);
161 	}
162 }
163 
164 void
165 fdtbus_pinctrl_configure(void)
166 {
167 	fdtbus_pinctrl_configure_node(OF_finddevice("/"));
168 }
169