diff options
Diffstat (limited to 'u-boot/common/hwconfig.c')
-rw-r--r-- | u-boot/common/hwconfig.c | 288 |
1 files changed, 288 insertions, 0 deletions
diff --git a/u-boot/common/hwconfig.c b/u-boot/common/hwconfig.c new file mode 100644 index 0000000..e47d4d7 --- /dev/null +++ b/u-boot/common/hwconfig.c @@ -0,0 +1,288 @@ +/* + * An inteface for configuring a hardware via u-boot environment. + * + * Copyright (c) 2009 MontaVista Software, Inc. + * Copyright 2011 Freescale Semiconductor, Inc. + * + * Author: Anton Vorontsov <avorontsov@ru.mvista.com> + * + * This program is free software; you can redistribute it and/or + * modify it under the terms of the GNU General Public License as + * published by the Free Software Foundation; either version 2 of + * the License, or (at your option) any later version. + */ + +#ifndef HWCONFIG_TEST +#include <config.h> +#include <common.h> +#include <exports.h> +#include <hwconfig.h> +#include <linux/types.h> +#include <linux/string.h> +#else +#include <stdio.h> +#include <stdlib.h> +#include <string.h> +#include <assert.h> +#define min(a, b) (((a) < (b)) ? (a) : (b)) +#endif /* HWCONFIG_TEST */ + +DECLARE_GLOBAL_DATA_PTR; + +static const char *hwconfig_parse(const char *opts, size_t maxlen, + const char *opt, char *stopchs, char eqch, + size_t *arglen) +{ + size_t optlen = strlen(opt); + char *str; + const char *start = opts; + const char *end; + +next: + str = strstr(opts, opt); + end = str + optlen; + if (end - start > maxlen) + return NULL; + + if (str && (str == opts || strpbrk(str - 1, stopchs) == str - 1) && + (strpbrk(end, stopchs) == end || *end == eqch || + *end == '\0')) { + const char *arg_end; + + if (!arglen) + return str; + + if (*end != eqch) + return NULL; + + arg_end = strpbrk(str, stopchs); + if (!arg_end) + *arglen = min(maxlen, strlen(str)) - optlen - 1; + else + *arglen = arg_end - end - 1; + + return end + 1; + } else if (str) { + opts = end; + goto next; + } + return NULL; +} + +const char cpu_hwconfig[] __attribute__((weak)) = ""; +const char board_hwconfig[] __attribute__((weak)) = ""; + +static const char *__hwconfig(const char *opt, size_t *arglen, + const char *env_hwconfig) +{ + const char *ret; + + /* if we are passed a buffer use it, otherwise try the environment */ + if (!env_hwconfig) { + if (!(gd->flags & GD_FLG_ENV_READY)) { + printf("WARNING: Calling __hwconfig without a buffer " + "and before environment is ready\n"); + return NULL; + } + env_hwconfig = getenv("hwconfig"); + } + + if (env_hwconfig) { + ret = hwconfig_parse(env_hwconfig, strlen(env_hwconfig), + opt, ";", ':', arglen); + if (ret) + return ret; + } + + ret = hwconfig_parse(board_hwconfig, strlen(board_hwconfig), + opt, ";", ':', arglen); + if (ret) + return ret; + + return hwconfig_parse(cpu_hwconfig, strlen(cpu_hwconfig), + opt, ";", ':', arglen); +} + +/* + * hwconfig_f - query if a particular hwconfig option is specified + * @opt: a string representing an option + * @buf: if non-NULL use this buffer to parse, otherwise try env + * + * This call can be used to find out whether U-Boot should configure + * a particular hardware option. + * + * Returns non-zero value if the hardware option can be used and thus + * should be configured, 0 otherwise. + * + * This function also returns non-zero value if CONFIG_HWCONFIG is + * undefined. + * + * Returning non-zero value without CONFIG_HWCONFIG has its crucial + * purpose: the hwconfig() call should be a "transparent" interface, + * e.g. if a board doesn't need hwconfig facility, then we assume + * that the board file only calls things that are actually used, so + * hwconfig() will always return true result. + */ +int hwconfig_f(const char *opt, char *buf) +{ + return !!__hwconfig(opt, NULL, buf); +} + +/* + * hwconfig_arg_f - get hwconfig option's argument + * @opt: a string representing an option + * @arglen: a pointer to an allocated size_t variable + * @buf: if non-NULL use this buffer to parse, otherwise try env + * + * Unlike hwconfig_f() function, this function returns a pointer to the + * start of the hwconfig arguments, if option is not found or it has + * no specified arguments, the function returns NULL pointer. + * + * If CONFIG_HWCONFIG is undefined, the function returns "", and + * arglen is set to 0. + */ +const char *hwconfig_arg_f(const char *opt, size_t *arglen, char *buf) +{ + return __hwconfig(opt, arglen, buf); +} + +/* + * hwconfig_arg_cmp_f - compare hwconfig option's argument + * @opt: a string representing an option + * @arg: a string for comparing an option's argument + * @buf: if non-NULL use this buffer to parse, otherwise try env + * + * This call is similar to hwconfig_arg_f, but instead of returning + * hwconfig argument and its length, it is comparing it to @arg. + * + * Returns non-zero value if @arg matches, 0 otherwise. + * + * If CONFIG_HWCONFIG is undefined, the function returns a non-zero + * value, i.e. the argument matches. + */ +int hwconfig_arg_cmp_f(const char *opt, const char *arg, char *buf) +{ + const char *argstr; + size_t arglen; + + argstr = hwconfig_arg_f(opt, &arglen, buf); + if (!argstr || arglen != strlen(arg)) + return 0; + + return !strncmp(argstr, arg, arglen); +} + +/* + * hwconfig_sub_f - query if a particular hwconfig sub-option is specified + * @opt: a string representing an option + * @subopt: a string representing a sub-option + * @buf: if non-NULL use this buffer to parse, otherwise try env + * + * This call is similar to hwconfig_f(), except that it takes additional + * argument @subopt. In this example: + * "dr_usb:mode=peripheral" + * "dr_usb" is an option, "mode" is a sub-option, and "peripheral" is its + * argument. + */ +int hwconfig_sub_f(const char *opt, const char *subopt, char *buf) +{ + size_t arglen; + const char *arg; + + arg = __hwconfig(opt, &arglen, buf); + if (!arg) + return 0; + return !!hwconfig_parse(arg, arglen, subopt, ",;", '=', NULL); +} + +/* + * hwconfig_subarg_f - get hwconfig sub-option's argument + * @opt: a string representing an option + * @subopt: a string representing a sub-option + * @subarglen: a pointer to an allocated size_t variable + * @buf: if non-NULL use this buffer to parse, otherwise try env + * + * This call is similar to hwconfig_arg_f(), except that it takes an + * additional argument @subopt, and so works with sub-options. + */ +const char *hwconfig_subarg_f(const char *opt, const char *subopt, + size_t *subarglen, char *buf) +{ + size_t arglen; + const char *arg; + + arg = __hwconfig(opt, &arglen, buf); + if (!arg) + return NULL; + return hwconfig_parse(arg, arglen, subopt, ",;", '=', subarglen); +} + +/* + * hwconfig_arg_cmp_f - compare hwconfig sub-option's argument + * @opt: a string representing an option + * @subopt: a string representing a sub-option + * @subarg: a string for comparing an sub-option's argument + * @buf: if non-NULL use this buffer to parse, otherwise try env + * + * This call is similar to hwconfig_arg_cmp_f, except that it takes an + * additional argument @subopt, and so works with sub-options. + */ +int hwconfig_subarg_cmp_f(const char *opt, const char *subopt, + const char *subarg, char *buf) +{ + const char *argstr; + size_t arglen; + + argstr = hwconfig_subarg_f(opt, subopt, &arglen, buf); + if (!argstr || arglen != strlen(subarg)) + return 0; + + return !strncmp(argstr, subarg, arglen); +} + +#ifdef HWCONFIG_TEST +int main() +{ + const char *ret; + size_t len; + + setenv("hwconfig", "key1:subkey1=value1,subkey2=value2;key2:value3;;;;" + "key3;:,:=;key4", 1); + + ret = hwconfig_arg("key1", &len); + printf("%zd %.*s\n", len, (int)len, ret); + assert(len == 29); + assert(hwconfig_arg_cmp("key1", "subkey1=value1,subkey2=value2")); + assert(!strncmp(ret, "subkey1=value1,subkey2=value2", len)); + + ret = hwconfig_subarg("key1", "subkey1", &len); + printf("%zd %.*s\n", len, (int)len, ret); + assert(len == 6); + assert(hwconfig_subarg_cmp("key1", "subkey1", "value1")); + assert(!strncmp(ret, "value1", len)); + + ret = hwconfig_subarg("key1", "subkey2", &len); + printf("%zd %.*s\n", len, (int)len, ret); + assert(len == 6); + assert(hwconfig_subarg_cmp("key1", "subkey2", "value2")); + assert(!strncmp(ret, "value2", len)); + + ret = hwconfig_arg("key2", &len); + printf("%zd %.*s\n", len, (int)len, ret); + assert(len == 6); + assert(hwconfig_arg_cmp("key2", "value3")); + assert(!strncmp(ret, "value3", len)); + + assert(hwconfig("key3")); + assert(hwconfig_arg("key4", &len) == NULL); + assert(hwconfig_arg("bogus", &len) == NULL); + + unsetenv("hwconfig"); + + assert(hwconfig(NULL) == 0); + assert(hwconfig("") == 0); + assert(hwconfig("key3") == 0); + + return 0; +} +#endif /* HWCONFIG_TEST */ |