1 // SPDX-License-Identifier: GPL-2.0-only 2 /* 3 * Core driver for the generic pin config portions of the pin control subsystem 4 * 5 * Copyright (C) 2011 ST-Ericsson SA 6 * Written on behalf of Linaro for ST-Ericsson 7 * 8 * Author: Linus Walleij <linus.walleij@linaro.org> 9 */ 10 11 #define pr_fmt(fmt) "generic pinconfig core: " fmt 12 13 #include <linux/array_size.h> 14 #include <linux/debugfs.h> 15 #include <linux/device.h> 16 #include <linux/init.h> 17 #include <linux/module.h> 18 #include <linux/of.h> 19 #include <linux/slab.h> 20 #include <linux/seq_file.h> 21 22 #include <linux/pinctrl/pinconf-generic.h> 23 #include <linux/pinctrl/pinconf.h> 24 #include <linux/pinctrl/pinctrl.h> 25 26 #include "core.h" 27 #include "pinconf.h" 28 #include "pinctrl-utils.h" 29 30 #ifdef CONFIG_DEBUG_FS 31 static const struct pin_config_item conf_items[] = { 32 PCONFDUMP(PIN_CONFIG_BIAS_BUS_HOLD, "input bias bus hold", NULL, false), 33 PCONFDUMP(PIN_CONFIG_BIAS_DISABLE, "input bias disabled", NULL, false), 34 PCONFDUMP(PIN_CONFIG_BIAS_HIGH_IMPEDANCE, "input bias high impedance", NULL, false), 35 PCONFDUMP(PIN_CONFIG_BIAS_PULL_DOWN, "input bias pull down", "ohms", true), 36 PCONFDUMP(PIN_CONFIG_BIAS_PULL_PIN_DEFAULT, 37 "input bias pull to pin specific state", "ohms", true), 38 PCONFDUMP(PIN_CONFIG_BIAS_PULL_UP, "input bias pull up", "ohms", true), 39 PCONFDUMP(PIN_CONFIG_DRIVE_OPEN_DRAIN, "output drive open drain", NULL, false), 40 PCONFDUMP(PIN_CONFIG_DRIVE_OPEN_SOURCE, "output drive open source", NULL, false), 41 PCONFDUMP(PIN_CONFIG_DRIVE_PUSH_PULL, "output drive push pull", NULL, false), 42 PCONFDUMP(PIN_CONFIG_DRIVE_STRENGTH, "output drive strength", "mA", true), 43 PCONFDUMP(PIN_CONFIG_DRIVE_STRENGTH_UA, "output drive strength", "uA", true), 44 PCONFDUMP(PIN_CONFIG_INPUT_DEBOUNCE, "input debounce", "usec", true), 45 PCONFDUMP(PIN_CONFIG_INPUT_ENABLE, "input enabled", NULL, false), 46 PCONFDUMP(PIN_CONFIG_INPUT_SCHMITT, "input schmitt trigger", NULL, false), 47 PCONFDUMP(PIN_CONFIG_INPUT_SCHMITT_UV, "input schmitt threshold", "uV", true), 48 PCONFDUMP(PIN_CONFIG_INPUT_SCHMITT_ENABLE, "input schmitt enabled", NULL, false), 49 PCONFDUMP(PIN_CONFIG_MODE_LOW_POWER, "pin low power", "mode", true), 50 PCONFDUMP(PIN_CONFIG_OUTPUT_ENABLE, "output enabled", NULL, false), 51 PCONFDUMP(PIN_CONFIG_OUTPUT, "pin output", "level", true), 52 PCONFDUMP(PIN_CONFIG_OUTPUT_IMPEDANCE_OHMS, "output impedance", "ohms", true), 53 PCONFDUMP(PIN_CONFIG_POWER_SOURCE, "pin power source", "selector", true), 54 PCONFDUMP(PIN_CONFIG_SLEEP_HARDWARE_STATE, "sleep hardware state", NULL, false), 55 PCONFDUMP(PIN_CONFIG_SLEW_RATE, "slew rate", NULL, true), 56 PCONFDUMP(PIN_CONFIG_SKEW_DELAY, "skew delay", NULL, true), 57 }; 58 59 static void pinconf_generic_dump_one(struct pinctrl_dev *pctldev, 60 struct seq_file *s, const char *gname, 61 unsigned int pin, 62 const struct pin_config_item *items, 63 int nitems, int *print_sep) 64 { 65 int i; 66 67 for (i = 0; i < nitems; i++) { 68 unsigned long config; 69 int ret; 70 71 /* We want to check out this parameter */ 72 config = pinconf_to_config_packed(items[i].param, 0); 73 if (gname) 74 ret = pin_config_group_get(dev_name(pctldev->dev), 75 gname, &config); 76 else 77 ret = pin_config_get_for_pin(pctldev, pin, &config); 78 /* These are legal errors */ 79 if (ret == -EINVAL || ret == -ENOTSUPP) 80 continue; 81 if (ret) { 82 seq_printf(s, "ERROR READING CONFIG SETTING %d ", i); 83 continue; 84 } 85 /* comma between multiple configs */ 86 if (*print_sep) 87 seq_puts(s, ", "); 88 *print_sep = 1; 89 seq_puts(s, items[i].display); 90 /* Print unit if available */ 91 if (items[i].has_arg) { 92 seq_printf(s, " (0x%x", 93 pinconf_to_config_argument(config)); 94 if (items[i].format) 95 seq_printf(s, " %s)", items[i].format); 96 else 97 seq_puts(s, ")"); 98 } 99 } 100 } 101 102 /** 103 * pinconf_generic_dump_pins - Print information about pin or group of pins 104 * @pctldev: Pincontrol device 105 * @s: File to print to 106 * @gname: Group name specifying pins 107 * @pin: Pin number specyfying pin 108 * 109 * Print the pinconf configuration for the requested pin(s) to @s. Pins can be 110 * specified either by pin using @pin or by group using @gname. Only one needs 111 * to be specified the other can be NULL/0. 112 */ 113 void pinconf_generic_dump_pins(struct pinctrl_dev *pctldev, struct seq_file *s, 114 const char *gname, unsigned int pin) 115 { 116 const struct pinconf_ops *ops = pctldev->desc->confops; 117 int print_sep = 0; 118 119 if (!ops->is_generic) 120 return; 121 122 /* generic parameters */ 123 pinconf_generic_dump_one(pctldev, s, gname, pin, conf_items, 124 ARRAY_SIZE(conf_items), &print_sep); 125 /* driver-specific parameters */ 126 if (pctldev->desc->num_custom_params && 127 pctldev->desc->custom_conf_items) 128 pinconf_generic_dump_one(pctldev, s, gname, pin, 129 pctldev->desc->custom_conf_items, 130 pctldev->desc->num_custom_params, 131 &print_sep); 132 } 133 134 void pinconf_generic_dump_config(struct pinctrl_dev *pctldev, 135 struct seq_file *s, unsigned long config) 136 { 137 int i; 138 139 for (i = 0; i < ARRAY_SIZE(conf_items); i++) { 140 if (pinconf_to_config_param(config) != conf_items[i].param) 141 continue; 142 seq_printf(s, "%s: 0x%x", conf_items[i].display, 143 pinconf_to_config_argument(config)); 144 } 145 146 if (!pctldev->desc->num_custom_params || 147 !pctldev->desc->custom_conf_items) 148 return; 149 150 for (i = 0; i < pctldev->desc->num_custom_params; i++) { 151 if (pinconf_to_config_param(config) != 152 pctldev->desc->custom_conf_items[i].param) 153 continue; 154 seq_printf(s, "%s: 0x%x", 155 pctldev->desc->custom_conf_items[i].display, 156 pinconf_to_config_argument(config)); 157 } 158 } 159 EXPORT_SYMBOL_GPL(pinconf_generic_dump_config); 160 #endif 161 162 #ifdef CONFIG_OF 163 static const struct pinconf_generic_params dt_params[] = { 164 { "bias-bus-hold", PIN_CONFIG_BIAS_BUS_HOLD, 0 }, 165 { "bias-disable", PIN_CONFIG_BIAS_DISABLE, 0 }, 166 { "bias-high-impedance", PIN_CONFIG_BIAS_HIGH_IMPEDANCE, 0 }, 167 { "bias-pull-up", PIN_CONFIG_BIAS_PULL_UP, 1 }, 168 { "bias-pull-pin-default", PIN_CONFIG_BIAS_PULL_PIN_DEFAULT, 1 }, 169 { "bias-pull-down", PIN_CONFIG_BIAS_PULL_DOWN, 1 }, 170 { "drive-open-drain", PIN_CONFIG_DRIVE_OPEN_DRAIN, 0 }, 171 { "drive-open-source", PIN_CONFIG_DRIVE_OPEN_SOURCE, 0 }, 172 { "drive-push-pull", PIN_CONFIG_DRIVE_PUSH_PULL, 0 }, 173 { "drive-strength", PIN_CONFIG_DRIVE_STRENGTH, 0 }, 174 { "drive-strength-microamp", PIN_CONFIG_DRIVE_STRENGTH_UA, 0 }, 175 { "input-debounce", PIN_CONFIG_INPUT_DEBOUNCE, 0 }, 176 { "input-disable", PIN_CONFIG_INPUT_ENABLE, 0 }, 177 { "input-enable", PIN_CONFIG_INPUT_ENABLE, 1 }, 178 { "input-schmitt", PIN_CONFIG_INPUT_SCHMITT, 0 }, 179 { "input-schmitt-disable", PIN_CONFIG_INPUT_SCHMITT_ENABLE, 0 }, 180 { "input-schmitt-enable", PIN_CONFIG_INPUT_SCHMITT_ENABLE, 1 }, 181 { "input-schmitt-microvolts", PIN_CONFIG_INPUT_SCHMITT_UV, 0 }, 182 { "low-power-disable", PIN_CONFIG_MODE_LOW_POWER, 0 }, 183 { "low-power-enable", PIN_CONFIG_MODE_LOW_POWER, 1 }, 184 { "output-disable", PIN_CONFIG_OUTPUT_ENABLE, 0 }, 185 { "output-enable", PIN_CONFIG_OUTPUT_ENABLE, 1 }, 186 { "output-high", PIN_CONFIG_OUTPUT, 1, }, 187 { "output-impedance-ohms", PIN_CONFIG_OUTPUT_IMPEDANCE_OHMS, 0 }, 188 { "output-low", PIN_CONFIG_OUTPUT, 0, }, 189 { "power-source", PIN_CONFIG_POWER_SOURCE, 0 }, 190 { "sleep-hardware-state", PIN_CONFIG_SLEEP_HARDWARE_STATE, 0 }, 191 { "slew-rate", PIN_CONFIG_SLEW_RATE, 0 }, 192 { "skew-delay", PIN_CONFIG_SKEW_DELAY, 0 }, 193 }; 194 195 /** 196 * parse_dt_cfg() - Parse DT pinconf parameters 197 * @np: DT node 198 * @params: Array of describing generic parameters 199 * @count: Number of entries in @params 200 * @cfg: Array of parsed config options 201 * @ncfg: Number of entries in @cfg 202 * 203 * Parse the config options described in @params from @np and puts the result 204 * in @cfg. @cfg does not need to be empty, entries are added beginning at 205 * @ncfg. @ncfg is updated to reflect the number of entries after parsing. @cfg 206 * needs to have enough memory allocated to hold all possible entries. 207 */ 208 static void parse_dt_cfg(struct device_node *np, 209 const struct pinconf_generic_params *params, 210 unsigned int count, unsigned long *cfg, 211 unsigned int *ncfg) 212 { 213 int i; 214 215 for (i = 0; i < count; i++) { 216 u32 val; 217 int ret; 218 const struct pinconf_generic_params *par = ¶ms[i]; 219 220 ret = of_property_read_u32(np, par->property, &val); 221 222 /* property not found */ 223 if (ret == -EINVAL) 224 continue; 225 226 /* use default value, when no value is specified */ 227 if (ret) 228 val = par->default_value; 229 230 pr_debug("found %s with value %u\n", par->property, val); 231 cfg[*ncfg] = pinconf_to_config_packed(par->param, val); 232 (*ncfg)++; 233 } 234 } 235 236 /** 237 * pinconf_generic_parse_dt_config() 238 * parse the config properties into generic pinconfig values. 239 * @np: node containing the pinconfig properties 240 * @pctldev: pincontrol device 241 * @configs: array with nconfigs entries containing the generic pinconf values 242 * must be freed when no longer necessary. 243 * @nconfigs: number of configurations 244 */ 245 int pinconf_generic_parse_dt_config(struct device_node *np, 246 struct pinctrl_dev *pctldev, 247 unsigned long **configs, 248 unsigned int *nconfigs) 249 { 250 unsigned long *cfg; 251 unsigned int max_cfg, ncfg = 0; 252 int ret; 253 254 if (!np) 255 return -EINVAL; 256 257 /* allocate a temporary array big enough to hold one of each option */ 258 max_cfg = ARRAY_SIZE(dt_params); 259 if (pctldev) 260 max_cfg += pctldev->desc->num_custom_params; 261 cfg = kcalloc(max_cfg, sizeof(*cfg), GFP_KERNEL); 262 if (!cfg) 263 return -ENOMEM; 264 265 parse_dt_cfg(np, dt_params, ARRAY_SIZE(dt_params), cfg, &ncfg); 266 if (pctldev && pctldev->desc->num_custom_params && 267 pctldev->desc->custom_params) 268 parse_dt_cfg(np, pctldev->desc->custom_params, 269 pctldev->desc->num_custom_params, cfg, &ncfg); 270 271 ret = 0; 272 273 /* no configs found at all */ 274 if (ncfg == 0) { 275 *configs = NULL; 276 *nconfigs = 0; 277 goto out; 278 } 279 280 /* 281 * Now limit the number of configs to the real number of 282 * found properties. 283 */ 284 *configs = kmemdup(cfg, ncfg * sizeof(unsigned long), GFP_KERNEL); 285 if (!*configs) { 286 ret = -ENOMEM; 287 goto out; 288 } 289 290 *nconfigs = ncfg; 291 292 out: 293 kfree(cfg); 294 return ret; 295 } 296 EXPORT_SYMBOL_GPL(pinconf_generic_parse_dt_config); 297 298 int pinconf_generic_dt_subnode_to_map(struct pinctrl_dev *pctldev, 299 struct device_node *np, struct pinctrl_map **map, 300 unsigned int *reserved_maps, unsigned int *num_maps, 301 enum pinctrl_map_type type) 302 { 303 int ret; 304 const char *function; 305 struct device *dev = pctldev->dev; 306 unsigned long *configs = NULL; 307 unsigned int num_configs = 0; 308 unsigned int reserve, strings_count; 309 struct property *prop; 310 const char *group; 311 const char *subnode_target_type = "pins"; 312 313 ret = of_property_count_strings(np, "pins"); 314 if (ret < 0) { 315 ret = of_property_count_strings(np, "groups"); 316 if (ret < 0) 317 /* skip this node; may contain config child nodes */ 318 return 0; 319 if (type == PIN_MAP_TYPE_INVALID) 320 type = PIN_MAP_TYPE_CONFIGS_GROUP; 321 subnode_target_type = "groups"; 322 } else { 323 if (type == PIN_MAP_TYPE_INVALID) 324 type = PIN_MAP_TYPE_CONFIGS_PIN; 325 } 326 strings_count = ret; 327 328 ret = of_property_read_string(np, "function", &function); 329 if (ret < 0) { 330 /* EINVAL=missing, which is fine since it's optional */ 331 if (ret != -EINVAL) 332 dev_err(dev, "%pOF: could not parse property function\n", 333 np); 334 function = NULL; 335 } 336 337 ret = pinconf_generic_parse_dt_config(np, pctldev, &configs, 338 &num_configs); 339 if (ret < 0) { 340 dev_err(dev, "%pOF: could not parse node property\n", np); 341 return ret; 342 } 343 344 reserve = 0; 345 if (function != NULL) 346 reserve++; 347 if (num_configs) 348 reserve++; 349 350 reserve *= strings_count; 351 352 ret = pinctrl_utils_reserve_map(pctldev, map, reserved_maps, 353 num_maps, reserve); 354 if (ret < 0) 355 goto exit; 356 357 of_property_for_each_string(np, subnode_target_type, prop, group) { 358 if (function) { 359 ret = pinctrl_utils_add_map_mux(pctldev, map, 360 reserved_maps, num_maps, group, 361 function); 362 if (ret < 0) 363 goto exit; 364 } 365 366 if (num_configs) { 367 ret = pinctrl_utils_add_map_configs(pctldev, map, 368 reserved_maps, num_maps, group, configs, 369 num_configs, type); 370 if (ret < 0) 371 goto exit; 372 } 373 } 374 ret = 0; 375 376 exit: 377 kfree(configs); 378 return ret; 379 } 380 EXPORT_SYMBOL_GPL(pinconf_generic_dt_subnode_to_map); 381 382 int pinconf_generic_dt_node_to_map(struct pinctrl_dev *pctldev, 383 struct device_node *np_config, struct pinctrl_map **map, 384 unsigned int *num_maps, enum pinctrl_map_type type) 385 { 386 unsigned int reserved_maps; 387 int ret; 388 389 reserved_maps = 0; 390 *map = NULL; 391 *num_maps = 0; 392 393 ret = pinconf_generic_dt_subnode_to_map(pctldev, np_config, map, 394 &reserved_maps, num_maps, type); 395 if (ret < 0) 396 goto exit; 397 398 for_each_available_child_of_node_scoped(np_config, np) { 399 ret = pinconf_generic_dt_subnode_to_map(pctldev, np, map, 400 &reserved_maps, num_maps, type); 401 if (ret < 0) 402 goto exit; 403 } 404 return 0; 405 406 exit: 407 pinctrl_utils_free_map(pctldev, *map, *num_maps); 408 return ret; 409 } 410 EXPORT_SYMBOL_GPL(pinconf_generic_dt_node_to_map); 411 412 void pinconf_generic_dt_free_map(struct pinctrl_dev *pctldev, 413 struct pinctrl_map *map, 414 unsigned int num_maps) 415 { 416 pinctrl_utils_free_map(pctldev, map, num_maps); 417 } 418 EXPORT_SYMBOL_GPL(pinconf_generic_dt_free_map); 419 420 #endif 421