| kconfig-language.rst (e9a83bd2322035ed9d7dcf35753d3f984d76c6a5) | kconfig-language.rst (168869492e7009b6861b615f1d030c99bc805e83) |
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| 1================ 2Kconfig Language 3================ 4 5Introduction 6------------ 7 8The configuration database is a collection of configuration options --- 39 unchanged lines hidden (view full) --- 48 49Menu attributes 50--------------- 51 52A menu entry can have a number of attributes. Not all of them are 53applicable everywhere (see syntax). 54 55- type definition: "bool"/"tristate"/"string"/"hex"/"int" | 1================ 2Kconfig Language 3================ 4 5Introduction 6------------ 7 8The configuration database is a collection of configuration options --- 39 unchanged lines hidden (view full) --- 48 49Menu attributes 50--------------- 51 52A menu entry can have a number of attributes. Not all of them are 53applicable everywhere (see syntax). 54 55- type definition: "bool"/"tristate"/"string"/"hex"/"int" |
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| 56 Every config option must have a type. There are only two basic types: 57 tristate and string; the other types are based on these two. The type 58 definition optionally accepts an input prompt, so these two examples 59 are equivalent:: 60 61 bool "Networking support" 62 63 and:: 64 65 bool 66 prompt "Networking support" 67 68- input prompt: "prompt" <prompt> ["if" <expr>] | 57 Every config option must have a type. There are only two basic types: 58 tristate and string; the other types are based on these two. The type 59 definition optionally accepts an input prompt, so these two examples 60 are equivalent:: 61 62 bool "Networking support" 63 64 and:: 65 66 bool 67 prompt "Networking support" 68 69- input prompt: "prompt" <prompt> ["if" <expr>] |
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| 69 Every menu entry can have at most one prompt, which is used to display 70 to the user. Optionally dependencies only for this prompt can be added 71 with "if". 72 73- default value: "default" <expr> ["if" <expr>] | 71 Every menu entry can have at most one prompt, which is used to display 72 to the user. Optionally dependencies only for this prompt can be added 73 with "if". 74 75- default value: "default" <expr> ["if" <expr>] |
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| 74 A config option can have any number of default values. If multiple 75 default values are visible, only the first defined one is active. 76 Default values are not limited to the menu entry where they are 77 defined. This means the default can be defined somewhere else or be 78 overridden by an earlier definition. 79 The default value is only assigned to the config symbol if no other 80 value was set by the user (via the input prompt above). If an input 81 prompt is visible the default value is presented to the user and can --- 25 unchanged lines hidden (view full) --- 107- type definition + default value:: 108 109 "def_bool"/"def_tristate" <expr> ["if" <expr>] 110 111 This is a shorthand notation for a type definition plus a value. 112 Optionally dependencies for this default value can be added with "if". 113 114- dependencies: "depends on" <expr> | 77 A config option can have any number of default values. If multiple 78 default values are visible, only the first defined one is active. 79 Default values are not limited to the menu entry where they are 80 defined. This means the default can be defined somewhere else or be 81 overridden by an earlier definition. 82 The default value is only assigned to the config symbol if no other 83 value was set by the user (via the input prompt above). If an input 84 prompt is visible the default value is presented to the user and can --- 25 unchanged lines hidden (view full) --- 110- type definition + default value:: 111 112 "def_bool"/"def_tristate" <expr> ["if" <expr>] 113 114 This is a shorthand notation for a type definition plus a value. 115 Optionally dependencies for this default value can be added with "if". 116 117- dependencies: "depends on" <expr> |
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| 115 This defines a dependency for this menu entry. If multiple 116 dependencies are defined, they are connected with '&&'. Dependencies 117 are applied to all other options within this menu entry (which also 118 accept an "if" expression), so these two examples are equivalent:: 119 120 bool "foo" if BAR 121 default y if BAR 122 123 and:: 124 125 depends on BAR 126 bool "foo" 127 default y 128 129- reverse dependencies: "select" <symbol> ["if" <expr>] | 119 This defines a dependency for this menu entry. If multiple 120 dependencies are defined, they are connected with '&&'. Dependencies 121 are applied to all other options within this menu entry (which also 122 accept an "if" expression), so these two examples are equivalent:: 123 124 bool "foo" if BAR 125 default y if BAR 126 127 and:: 128 129 depends on BAR 130 bool "foo" 131 default y 132 133- reverse dependencies: "select" <symbol> ["if" <expr>] |
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| 130 While normal dependencies reduce the upper limit of a symbol (see 131 below), reverse dependencies can be used to force a lower limit of 132 another symbol. The value of the current menu symbol is used as the 133 minimal value <symbol> can be set to. If <symbol> is selected multiple 134 times, the limit is set to the largest selection. 135 Reverse dependencies can only be used with boolean or tristate 136 symbols. 137 138 Note: 139 select should be used with care. select will force 140 a symbol to a value without visiting the dependencies. 141 By abusing select you are able to select a symbol FOO even 142 if FOO depends on BAR that is not set. 143 In general use select only for non-visible symbols 144 (no prompts anywhere) and for symbols with no dependencies. 145 That will limit the usefulness but on the other hand avoid 146 the illegal configurations all over. 147 148- weak reverse dependencies: "imply" <symbol> ["if" <expr>] | 135 While normal dependencies reduce the upper limit of a symbol (see 136 below), reverse dependencies can be used to force a lower limit of 137 another symbol. The value of the current menu symbol is used as the 138 minimal value <symbol> can be set to. If <symbol> is selected multiple 139 times, the limit is set to the largest selection. 140 Reverse dependencies can only be used with boolean or tristate 141 symbols. 142 143 Note: 144 select should be used with care. select will force 145 a symbol to a value without visiting the dependencies. 146 By abusing select you are able to select a symbol FOO even 147 if FOO depends on BAR that is not set. 148 In general use select only for non-visible symbols 149 (no prompts anywhere) and for symbols with no dependencies. 150 That will limit the usefulness but on the other hand avoid 151 the illegal configurations all over. 152 153- weak reverse dependencies: "imply" <symbol> ["if" <expr>] |
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| 149 This is similar to "select" as it enforces a lower limit on another 150 symbol except that the "implied" symbol's value may still be set to n 151 from a direct dependency or with a visible prompt. 152 153 Given the following example:: 154 155 config FOO 156 tristate --- 14 unchanged lines hidden (view full) --- 171 y n * N 172 === === ============= ============== 173 174 This is useful e.g. with multiple drivers that want to indicate their 175 ability to hook into a secondary subsystem while allowing the user to 176 configure that subsystem out without also having to unset these drivers. 177 178- limiting menu display: "visible if" <expr> | 155 This is similar to "select" as it enforces a lower limit on another 156 symbol except that the "implied" symbol's value may still be set to n 157 from a direct dependency or with a visible prompt. 158 159 Given the following example:: 160 161 config FOO 162 tristate --- 14 unchanged lines hidden (view full) --- 177 y n * N 178 === === ============= ============== 179 180 This is useful e.g. with multiple drivers that want to indicate their 181 ability to hook into a secondary subsystem while allowing the user to 182 configure that subsystem out without also having to unset these drivers. 183 184- limiting menu display: "visible if" <expr> |
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| 179 This attribute is only applicable to menu blocks, if the condition is 180 false, the menu block is not displayed to the user (the symbols 181 contained there can still be selected by other symbols, though). It is 182 similar to a conditional "prompt" attribute for individual menu 183 entries. Default value of "visible" is true. 184 185- numerical ranges: "range" <symbol> <symbol> ["if" <expr>] | 186 This attribute is only applicable to menu blocks, if the condition is 187 false, the menu block is not displayed to the user (the symbols 188 contained there can still be selected by other symbols, though). It is 189 similar to a conditional "prompt" attribute for individual menu 190 entries. Default value of "visible" is true. 191 192- numerical ranges: "range" <symbol> <symbol> ["if" <expr>] |
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| 186 This allows to limit the range of possible input values for int 187 and hex symbols. The user can only input a value which is larger than 188 or equal to the first symbol and smaller than or equal to the second 189 symbol. 190 191- help text: "help" or "---help---" | 194 This allows to limit the range of possible input values for int 195 and hex symbols. The user can only input a value which is larger than 196 or equal to the first symbol and smaller than or equal to the second 197 symbol. 198 199- help text: "help" or "---help---" |
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| 192 This defines a help text. The end of the help text is determined by 193 the indentation level, this means it ends at the first line which has 194 a smaller indentation than the first line of the help text. 195 "---help---" and "help" do not differ in behaviour, "---help---" is 196 used to help visually separate configuration logic from help within 197 the file as an aid to developers. 198 199- misc options: "option" <symbol>[=<value>] | 201 This defines a help text. The end of the help text is determined by 202 the indentation level, this means it ends at the first line which has 203 a smaller indentation than the first line of the help text. 204 "---help---" and "help" do not differ in behaviour, "---help---" is 205 used to help visually separate configuration logic from help within 206 the file as an aid to developers. 207 208- misc options: "option" <symbol>[=<value>] |
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| 200 Various less common options can be defined via this option syntax, 201 which can modify the behaviour of the menu entry and its config 202 symbol. These options are currently possible: 203 204 - "defconfig_list" 205 This declares a list of default entries which can be used when 206 looking for the default configuration (which is used when the main 207 .config doesn't exists yet.) --- 112 unchanged lines hidden (view full) --- 320- comment 321- menu/endmenu 322- if/endif 323- source 324 325The first five also start the definition of a menu entry. 326 327config:: | 210 Various less common options can be defined via this option syntax, 211 which can modify the behaviour of the menu entry and its config 212 symbol. These options are currently possible: 213 214 - "defconfig_list" 215 This declares a list of default entries which can be used when 216 looking for the default configuration (which is used when the main 217 .config doesn't exists yet.) --- 112 unchanged lines hidden (view full) --- 330- comment 331- menu/endmenu 332- if/endif 333- source 334 335The first five also start the definition of a menu entry. 336 337config:: |
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| 328 "config" <symbol> 329 <config options> 330 331This defines a config symbol <symbol> and accepts any of above 332attributes as options. 333 334menuconfig:: | 339 "config" <symbol> 340 <config options> 341 342This defines a config symbol <symbol> and accepts any of above 343attributes as options. 344 345menuconfig:: |
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| 335 "menuconfig" <symbol> 336 <config options> 337 338This is similar to the simple config entry above, but it also gives a 339hint to front ends, that all suboptions should be displayed as a 340separate list of options. To make sure all the suboptions will really 341show up under the menuconfig entry and not outside of it, every item 342from the <config options> list must depend on the menuconfig symbol. --- 347 unchanged lines hidden --- | 347 "menuconfig" <symbol> 348 <config options> 349 350This is similar to the simple config entry above, but it also gives a 351hint to front ends, that all suboptions should be displayed as a 352separate list of options. To make sure all the suboptions will really 353show up under the menuconfig entry and not outside of it, every item 354from the <config options> list must depend on the menuconfig symbol. --- 347 unchanged lines hidden --- |