1 /* 2 * Core driver for the generic pin config portions of the pin control subsystem 3 * 4 * Copyright (C) 2011 ST-Ericsson SA 5 * Written on behalf of Linaro for ST-Ericsson 6 * 7 * Author: Linus Walleij <linus.walleij@linaro.org> 8 * 9 * License terms: GNU General Public License (GPL) version 2 10 */ 11 12 #define pr_fmt(fmt) "generic pinconfig core: " fmt 13 14 #include <linux/kernel.h> 15 #include <linux/module.h> 16 #include <linux/init.h> 17 #include <linux/device.h> 18 #include <linux/slab.h> 19 #include <linux/debugfs.h> 20 #include <linux/seq_file.h> 21 #include <linux/pinctrl/pinctrl.h> 22 #include <linux/pinctrl/pinconf.h> 23 #include <linux/pinctrl/pinconf-generic.h> 24 #include <linux/of.h> 25 #include "core.h" 26 #include "pinconf.h" 27 #include "pinctrl-utils.h" 28 29 #ifdef CONFIG_DEBUG_FS 30 static const struct pin_config_item conf_items[] = { 31 PCONFDUMP(PIN_CONFIG_BIAS_BUS_HOLD, "input bias bus hold", NULL, false), 32 PCONFDUMP(PIN_CONFIG_BIAS_DISABLE, "input bias disabled", NULL, false), 33 PCONFDUMP(PIN_CONFIG_BIAS_HIGH_IMPEDANCE, "input bias high impedance", NULL, false), 34 PCONFDUMP(PIN_CONFIG_BIAS_PULL_DOWN, "input bias pull down", NULL, false), 35 PCONFDUMP(PIN_CONFIG_BIAS_PULL_PIN_DEFAULT, 36 "input bias pull to pin specific state", NULL, false), 37 PCONFDUMP(PIN_CONFIG_BIAS_PULL_UP, "input bias pull up", NULL, false), 38 PCONFDUMP(PIN_CONFIG_DRIVE_OPEN_DRAIN, "output drive open drain", NULL, false), 39 PCONFDUMP(PIN_CONFIG_DRIVE_OPEN_SOURCE, "output drive open source", NULL, false), 40 PCONFDUMP(PIN_CONFIG_DRIVE_PUSH_PULL, "output drive push pull", NULL, false), 41 PCONFDUMP(PIN_CONFIG_DRIVE_STRENGTH, "output drive strength", "mA", true), 42 PCONFDUMP(PIN_CONFIG_INPUT_DEBOUNCE, "input debounce", "usec", true), 43 PCONFDUMP(PIN_CONFIG_INPUT_ENABLE, "input enabled", NULL, false), 44 PCONFDUMP(PIN_CONFIG_INPUT_SCHMITT, "input schmitt trigger", NULL, false), 45 PCONFDUMP(PIN_CONFIG_INPUT_SCHMITT_ENABLE, "input schmitt enabled", NULL, false), 46 PCONFDUMP(PIN_CONFIG_LOW_POWER_MODE, "pin low power", "mode", true), 47 PCONFDUMP(PIN_CONFIG_OUTPUT_ENABLE, "output enabled", NULL, false), 48 PCONFDUMP(PIN_CONFIG_OUTPUT, "pin output", "level", true), 49 PCONFDUMP(PIN_CONFIG_POWER_SOURCE, "pin power source", "selector", true), 50 PCONFDUMP(PIN_CONFIG_SLEEP_HARDWARE_STATE, "sleep hardware state", NULL, false), 51 PCONFDUMP(PIN_CONFIG_SLEW_RATE, "slew rate", NULL, true), 52 }; 53 54 static void pinconf_generic_dump_one(struct pinctrl_dev *pctldev, 55 struct seq_file *s, const char *gname, 56 unsigned pin, 57 const struct pin_config_item *items, 58 int nitems, int *print_sep) 59 { 60 int i; 61 62 for (i = 0; i < nitems; i++) { 63 unsigned long config; 64 int ret; 65 66 /* We want to check out this parameter */ 67 config = pinconf_to_config_packed(items[i].param, 0); 68 if (gname) 69 ret = pin_config_group_get(dev_name(pctldev->dev), 70 gname, &config); 71 else 72 ret = pin_config_get_for_pin(pctldev, pin, &config); 73 /* These are legal errors */ 74 if (ret == -EINVAL || ret == -ENOTSUPP) 75 continue; 76 if (ret) { 77 seq_printf(s, "ERROR READING CONFIG SETTING %d ", i); 78 continue; 79 } 80 /* comma between multiple configs */ 81 if (*print_sep) 82 seq_puts(s, ", "); 83 *print_sep = 1; 84 seq_puts(s, items[i].display); 85 /* Print unit if available */ 86 if (items[i].has_arg) { 87 seq_printf(s, " (%u", 88 pinconf_to_config_argument(config)); 89 if (items[i].format) 90 seq_printf(s, " %s)", items[i].format); 91 else 92 seq_puts(s, ")"); 93 } 94 } 95 } 96 97 /** 98 * pinconf_generic_dump_pins - Print information about pin or group of pins 99 * @pctldev: Pincontrol device 100 * @s: File to print to 101 * @gname: Group name specifying pins 102 * @pin: Pin number specyfying pin 103 * 104 * Print the pinconf configuration for the requested pin(s) to @s. Pins can be 105 * specified either by pin using @pin or by group using @gname. Only one needs 106 * to be specified the other can be NULL/0. 107 */ 108 void pinconf_generic_dump_pins(struct pinctrl_dev *pctldev, struct seq_file *s, 109 const char *gname, unsigned pin) 110 { 111 const struct pinconf_ops *ops = pctldev->desc->confops; 112 int print_sep = 0; 113 114 if (!ops->is_generic) 115 return; 116 117 /* generic parameters */ 118 pinconf_generic_dump_one(pctldev, s, gname, pin, conf_items, 119 ARRAY_SIZE(conf_items), &print_sep); 120 /* driver-specific parameters */ 121 if (pctldev->desc->num_custom_params && 122 pctldev->desc->custom_conf_items) 123 pinconf_generic_dump_one(pctldev, s, gname, pin, 124 pctldev->desc->custom_conf_items, 125 pctldev->desc->num_custom_params, 126 &print_sep); 127 } 128 129 void pinconf_generic_dump_config(struct pinctrl_dev *pctldev, 130 struct seq_file *s, unsigned long config) 131 { 132 int i; 133 134 for (i = 0; i < ARRAY_SIZE(conf_items); i++) { 135 if (pinconf_to_config_param(config) != conf_items[i].param) 136 continue; 137 seq_printf(s, "%s: 0x%x", conf_items[i].display, 138 pinconf_to_config_argument(config)); 139 } 140 141 if (!pctldev->desc->num_custom_params || 142 !pctldev->desc->custom_conf_items) 143 return; 144 145 for (i = 0; i < pctldev->desc->num_custom_params; i++) { 146 if (pinconf_to_config_param(config) != 147 pctldev->desc->custom_conf_items[i].param) 148 continue; 149 seq_printf(s, "%s: 0x%x", 150 pctldev->desc->custom_conf_items[i].display, 151 pinconf_to_config_argument(config)); 152 } 153 } 154 EXPORT_SYMBOL_GPL(pinconf_generic_dump_config); 155 #endif 156 157 #ifdef CONFIG_OF 158 static const struct pinconf_generic_params dt_params[] = { 159 { "bias-bus-hold", PIN_CONFIG_BIAS_BUS_HOLD, 0 }, 160 { "bias-disable", PIN_CONFIG_BIAS_DISABLE, 0 }, 161 { "bias-high-impedance", PIN_CONFIG_BIAS_HIGH_IMPEDANCE, 0 }, 162 { "bias-pull-up", PIN_CONFIG_BIAS_PULL_UP, 1 }, 163 { "bias-pull-pin-default", PIN_CONFIG_BIAS_PULL_PIN_DEFAULT, 1 }, 164 { "bias-pull-down", PIN_CONFIG_BIAS_PULL_DOWN, 1 }, 165 { "drive-open-drain", PIN_CONFIG_DRIVE_OPEN_DRAIN, 0 }, 166 { "drive-open-source", PIN_CONFIG_DRIVE_OPEN_SOURCE, 0 }, 167 { "drive-push-pull", PIN_CONFIG_DRIVE_PUSH_PULL, 0 }, 168 { "drive-strength", PIN_CONFIG_DRIVE_STRENGTH, 0 }, 169 { "input-debounce", PIN_CONFIG_INPUT_DEBOUNCE, 0 }, 170 { "input-disable", PIN_CONFIG_INPUT_ENABLE, 0 }, 171 { "input-enable", PIN_CONFIG_INPUT_ENABLE, 1 }, 172 { "input-schmitt", PIN_CONFIG_INPUT_SCHMITT, 0 }, 173 { "input-schmitt-disable", PIN_CONFIG_INPUT_SCHMITT_ENABLE, 0 }, 174 { "input-schmitt-enable", PIN_CONFIG_INPUT_SCHMITT_ENABLE, 1 }, 175 { "low-power-disable", PIN_CONFIG_LOW_POWER_MODE, 0 }, 176 { "low-power-enable", PIN_CONFIG_LOW_POWER_MODE, 1 }, 177 { "output-disable", PIN_CONFIG_OUTPUT_ENABLE, 0 }, 178 { "output-enable", PIN_CONFIG_OUTPUT_ENABLE, 1 }, 179 { "output-high", PIN_CONFIG_OUTPUT, 1, }, 180 { "output-low", PIN_CONFIG_OUTPUT, 0, }, 181 { "power-source", PIN_CONFIG_POWER_SOURCE, 0 }, 182 { "sleep-hardware-state", PIN_CONFIG_SLEEP_HARDWARE_STATE, 0 }, 183 { "slew-rate", PIN_CONFIG_SLEW_RATE, 0 }, 184 }; 185 186 /** 187 * parse_dt_cfg() - Parse DT pinconf parameters 188 * @np: DT node 189 * @params: Array of describing generic parameters 190 * @count: Number of entries in @params 191 * @cfg: Array of parsed config options 192 * @ncfg: Number of entries in @cfg 193 * 194 * Parse the config options described in @params from @np and puts the result 195 * in @cfg. @cfg does not need to be empty, entries are added beginning at 196 * @ncfg. @ncfg is updated to reflect the number of entries after parsing. @cfg 197 * needs to have enough memory allocated to hold all possible entries. 198 */ 199 static void parse_dt_cfg(struct device_node *np, 200 const struct pinconf_generic_params *params, 201 unsigned int count, unsigned long *cfg, 202 unsigned int *ncfg) 203 { 204 int i; 205 206 for (i = 0; i < count; i++) { 207 u32 val; 208 int ret; 209 const struct pinconf_generic_params *par = ¶ms[i]; 210 211 ret = of_property_read_u32(np, par->property, &val); 212 213 /* property not found */ 214 if (ret == -EINVAL) 215 continue; 216 217 /* use default value, when no value is specified */ 218 if (ret) 219 val = par->default_value; 220 221 pr_debug("found %s with value %u\n", par->property, val); 222 cfg[*ncfg] = pinconf_to_config_packed(par->param, val); 223 (*ncfg)++; 224 } 225 } 226 227 /** 228 * pinconf_generic_parse_dt_config() 229 * parse the config properties into generic pinconfig values. 230 * @np: node containing the pinconfig properties 231 * @configs: array with nconfigs entries containing the generic pinconf values 232 * must be freed when no longer necessary. 233 * @nconfigs: umber of configurations 234 */ 235 int pinconf_generic_parse_dt_config(struct device_node *np, 236 struct pinctrl_dev *pctldev, 237 unsigned long **configs, 238 unsigned int *nconfigs) 239 { 240 unsigned long *cfg; 241 unsigned int max_cfg, ncfg = 0; 242 int ret; 243 244 if (!np) 245 return -EINVAL; 246 247 /* allocate a temporary array big enough to hold one of each option */ 248 max_cfg = ARRAY_SIZE(dt_params); 249 if (pctldev) 250 max_cfg += pctldev->desc->num_custom_params; 251 cfg = kcalloc(max_cfg, sizeof(*cfg), GFP_KERNEL); 252 if (!cfg) 253 return -ENOMEM; 254 255 parse_dt_cfg(np, dt_params, ARRAY_SIZE(dt_params), cfg, &ncfg); 256 if (pctldev && pctldev->desc->num_custom_params && 257 pctldev->desc->custom_params) 258 parse_dt_cfg(np, pctldev->desc->custom_params, 259 pctldev->desc->num_custom_params, cfg, &ncfg); 260 261 ret = 0; 262 263 /* no configs found at all */ 264 if (ncfg == 0) { 265 *configs = NULL; 266 *nconfigs = 0; 267 goto out; 268 } 269 270 /* 271 * Now limit the number of configs to the real number of 272 * found properties. 273 */ 274 *configs = kmemdup(cfg, ncfg * sizeof(unsigned long), GFP_KERNEL); 275 if (!*configs) { 276 ret = -ENOMEM; 277 goto out; 278 } 279 280 *nconfigs = ncfg; 281 282 out: 283 kfree(cfg); 284 return ret; 285 } 286 287 int pinconf_generic_dt_subnode_to_map(struct pinctrl_dev *pctldev, 288 struct device_node *np, struct pinctrl_map **map, 289 unsigned *reserved_maps, unsigned *num_maps, 290 enum pinctrl_map_type type) 291 { 292 int ret; 293 const char *function; 294 struct device *dev = pctldev->dev; 295 unsigned long *configs = NULL; 296 unsigned num_configs = 0; 297 unsigned reserve, strings_count; 298 struct property *prop; 299 const char *group; 300 const char *subnode_target_type = "pins"; 301 302 ret = of_property_count_strings(np, "pins"); 303 if (ret < 0) { 304 ret = of_property_count_strings(np, "groups"); 305 if (ret < 0) 306 /* skip this node; may contain config child nodes */ 307 return 0; 308 if (type == PIN_MAP_TYPE_INVALID) 309 type = PIN_MAP_TYPE_CONFIGS_GROUP; 310 subnode_target_type = "groups"; 311 } else { 312 if (type == PIN_MAP_TYPE_INVALID) 313 type = PIN_MAP_TYPE_CONFIGS_PIN; 314 } 315 strings_count = ret; 316 317 ret = of_property_read_string(np, "function", &function); 318 if (ret < 0) { 319 /* EINVAL=missing, which is fine since it's optional */ 320 if (ret != -EINVAL) 321 dev_err(dev, "%pOF: could not parse property function\n", 322 np); 323 function = NULL; 324 } 325 326 ret = pinconf_generic_parse_dt_config(np, pctldev, &configs, 327 &num_configs); 328 if (ret < 0) { 329 dev_err(dev, "%pOF: could not parse node property\n", np); 330 return ret; 331 } 332 333 reserve = 0; 334 if (function != NULL) 335 reserve++; 336 if (num_configs) 337 reserve++; 338 339 reserve *= strings_count; 340 341 ret = pinctrl_utils_reserve_map(pctldev, map, reserved_maps, 342 num_maps, reserve); 343 if (ret < 0) 344 goto exit; 345 346 of_property_for_each_string(np, subnode_target_type, prop, group) { 347 if (function) { 348 ret = pinctrl_utils_add_map_mux(pctldev, map, 349 reserved_maps, num_maps, group, 350 function); 351 if (ret < 0) 352 goto exit; 353 } 354 355 if (num_configs) { 356 ret = pinctrl_utils_add_map_configs(pctldev, map, 357 reserved_maps, num_maps, group, configs, 358 num_configs, type); 359 if (ret < 0) 360 goto exit; 361 } 362 } 363 ret = 0; 364 365 exit: 366 kfree(configs); 367 return ret; 368 } 369 EXPORT_SYMBOL_GPL(pinconf_generic_dt_subnode_to_map); 370 371 int pinconf_generic_dt_node_to_map(struct pinctrl_dev *pctldev, 372 struct device_node *np_config, struct pinctrl_map **map, 373 unsigned *num_maps, enum pinctrl_map_type type) 374 { 375 unsigned reserved_maps; 376 struct device_node *np; 377 int ret; 378 379 reserved_maps = 0; 380 *map = NULL; 381 *num_maps = 0; 382 383 ret = pinconf_generic_dt_subnode_to_map(pctldev, np_config, map, 384 &reserved_maps, num_maps, type); 385 if (ret < 0) 386 goto exit; 387 388 for_each_available_child_of_node(np_config, np) { 389 ret = pinconf_generic_dt_subnode_to_map(pctldev, np, map, 390 &reserved_maps, num_maps, type); 391 if (ret < 0) 392 goto exit; 393 } 394 return 0; 395 396 exit: 397 pinctrl_utils_free_map(pctldev, *map, *num_maps); 398 return ret; 399 } 400 EXPORT_SYMBOL_GPL(pinconf_generic_dt_node_to_map); 401 402 void pinconf_generic_dt_free_map(struct pinctrl_dev *pctldev, 403 struct pinctrl_map *map, 404 unsigned num_maps) 405 { 406 pinctrl_utils_free_map(pctldev, map, num_maps); 407 } 408 EXPORT_SYMBOL_GPL(pinconf_generic_dt_free_map); 409 410 #endif 411