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