2 * An inteface for configuring a hardware via u-boot environment.
4 * Copyright (c) 2009 MontaVista Software, Inc.
5 * Copyright 2011 Freescale Semiconductor, Inc.
7 * Author: Anton Vorontsov <avorontsov@ru.mvista.com>
9 * SPDX-License-Identifier: GPL-2.0+
17 #include <linux/types.h>
18 #include <linux/string.h>
24 #define min(a, b) (((a) < (b)) ? (a) : (b))
25 #endif /* HWCONFIG_TEST */
27 DECLARE_GLOBAL_DATA_PTR;
29 static const char *hwconfig_parse(const char *opts, size_t maxlen,
30 const char *opt, char *stopchs, char eqch,
33 size_t optlen = strlen(opt);
35 const char *start = opts;
39 str = strstr(opts, opt);
41 if (end - start > maxlen)
44 if (str && (str == opts || strpbrk(str - 1, stopchs) == str - 1) &&
45 (strpbrk(end, stopchs) == end || *end == eqch ||
55 arg_end = strpbrk(str, stopchs);
57 *arglen = min(maxlen, strlen(str)) - optlen - 1;
59 *arglen = arg_end - end - 1;
69 const char cpu_hwconfig[] __attribute__((weak)) = "";
70 const char board_hwconfig[] __attribute__((weak)) = "";
72 static const char *__hwconfig(const char *opt, size_t *arglen,
73 const char *env_hwconfig)
77 /* if we are passed a buffer use it, otherwise try the environment */
79 if (!(gd->flags & GD_FLG_ENV_READY)) {
80 printf("WARNING: Calling __hwconfig without a buffer "
81 "and before environment is ready\n");
84 env_hwconfig = getenv("hwconfig");
88 ret = hwconfig_parse(env_hwconfig, strlen(env_hwconfig),
89 opt, ";", ':', arglen);
94 ret = hwconfig_parse(board_hwconfig, strlen(board_hwconfig),
95 opt, ";", ':', arglen);
99 return hwconfig_parse(cpu_hwconfig, strlen(cpu_hwconfig),
100 opt, ";", ':', arglen);
104 * hwconfig_f - query if a particular hwconfig option is specified
105 * @opt: a string representing an option
106 * @buf: if non-NULL use this buffer to parse, otherwise try env
108 * This call can be used to find out whether U-Boot should configure
109 * a particular hardware option.
111 * Returns non-zero value if the hardware option can be used and thus
112 * should be configured, 0 otherwise.
114 * This function also returns non-zero value if CONFIG_HWCONFIG is
117 * Returning non-zero value without CONFIG_HWCONFIG has its crucial
118 * purpose: the hwconfig() call should be a "transparent" interface,
119 * e.g. if a board doesn't need hwconfig facility, then we assume
120 * that the board file only calls things that are actually used, so
121 * hwconfig() will always return true result.
123 int hwconfig_f(const char *opt, char *buf)
125 return !!__hwconfig(opt, NULL, buf);
129 * hwconfig_arg_f - get hwconfig option's argument
130 * @opt: a string representing an option
131 * @arglen: a pointer to an allocated size_t variable
132 * @buf: if non-NULL use this buffer to parse, otherwise try env
134 * Unlike hwconfig_f() function, this function returns a pointer to the
135 * start of the hwconfig arguments, if option is not found or it has
136 * no specified arguments, the function returns NULL pointer.
138 * If CONFIG_HWCONFIG is undefined, the function returns "", and
139 * arglen is set to 0.
141 const char *hwconfig_arg_f(const char *opt, size_t *arglen, char *buf)
143 return __hwconfig(opt, arglen, buf);
147 * hwconfig_arg_cmp_f - compare hwconfig option's argument
148 * @opt: a string representing an option
149 * @arg: a string for comparing an option's argument
150 * @buf: if non-NULL use this buffer to parse, otherwise try env
152 * This call is similar to hwconfig_arg_f, but instead of returning
153 * hwconfig argument and its length, it is comparing it to @arg.
155 * Returns non-zero value if @arg matches, 0 otherwise.
157 * If CONFIG_HWCONFIG is undefined, the function returns a non-zero
158 * value, i.e. the argument matches.
160 int hwconfig_arg_cmp_f(const char *opt, const char *arg, char *buf)
165 argstr = hwconfig_arg_f(opt, &arglen, buf);
166 if (!argstr || arglen != strlen(arg))
169 return !strncmp(argstr, arg, arglen);
173 * hwconfig_sub_f - query if a particular hwconfig sub-option is specified
174 * @opt: a string representing an option
175 * @subopt: a string representing a sub-option
176 * @buf: if non-NULL use this buffer to parse, otherwise try env
178 * This call is similar to hwconfig_f(), except that it takes additional
179 * argument @subopt. In this example:
180 * "dr_usb:mode=peripheral"
181 * "dr_usb" is an option, "mode" is a sub-option, and "peripheral" is its
184 int hwconfig_sub_f(const char *opt, const char *subopt, char *buf)
189 arg = __hwconfig(opt, &arglen, buf);
192 return !!hwconfig_parse(arg, arglen, subopt, ",;", '=', NULL);
196 * hwconfig_subarg_f - get hwconfig sub-option's argument
197 * @opt: a string representing an option
198 * @subopt: a string representing a sub-option
199 * @subarglen: a pointer to an allocated size_t variable
200 * @buf: if non-NULL use this buffer to parse, otherwise try env
202 * This call is similar to hwconfig_arg_f(), except that it takes an
203 * additional argument @subopt, and so works with sub-options.
205 const char *hwconfig_subarg_f(const char *opt, const char *subopt,
206 size_t *subarglen, char *buf)
211 arg = __hwconfig(opt, &arglen, buf);
214 return hwconfig_parse(arg, arglen, subopt, ",;", '=', subarglen);
218 * hwconfig_arg_cmp_f - compare hwconfig sub-option's argument
219 * @opt: a string representing an option
220 * @subopt: a string representing a sub-option
221 * @subarg: a string for comparing an sub-option's argument
222 * @buf: if non-NULL use this buffer to parse, otherwise try env
224 * This call is similar to hwconfig_arg_cmp_f, except that it takes an
225 * additional argument @subopt, and so works with sub-options.
227 int hwconfig_subarg_cmp_f(const char *opt, const char *subopt,
228 const char *subarg, char *buf)
233 argstr = hwconfig_subarg_f(opt, subopt, &arglen, buf);
234 if (!argstr || arglen != strlen(subarg))
237 return !strncmp(argstr, subarg, arglen);
246 setenv("hwconfig", "key1:subkey1=value1,subkey2=value2;key2:value3;;;;"
247 "key3;:,:=;key4", 1);
249 ret = hwconfig_arg("key1", &len);
250 printf("%zd %.*s\n", len, (int)len, ret);
252 assert(hwconfig_arg_cmp("key1", "subkey1=value1,subkey2=value2"));
253 assert(!strncmp(ret, "subkey1=value1,subkey2=value2", len));
255 ret = hwconfig_subarg("key1", "subkey1", &len);
256 printf("%zd %.*s\n", len, (int)len, ret);
258 assert(hwconfig_subarg_cmp("key1", "subkey1", "value1"));
259 assert(!strncmp(ret, "value1", len));
261 ret = hwconfig_subarg("key1", "subkey2", &len);
262 printf("%zd %.*s\n", len, (int)len, ret);
264 assert(hwconfig_subarg_cmp("key1", "subkey2", "value2"));
265 assert(!strncmp(ret, "value2", len));
267 ret = hwconfig_arg("key2", &len);
268 printf("%zd %.*s\n", len, (int)len, ret);
270 assert(hwconfig_arg_cmp("key2", "value3"));
271 assert(!strncmp(ret, "value3", len));
273 assert(hwconfig("key3"));
274 assert(hwconfig_arg("key4", &len) == NULL);
275 assert(hwconfig_arg("bogus", &len) == NULL);
277 unsetenv("hwconfig");
279 assert(hwconfig(NULL) == 0);
280 assert(hwconfig("") == 0);
281 assert(hwconfig("key3") == 0);
285 #endif /* HWCONFIG_TEST */