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_INPUT_DEBOUNCE, "input debounce", "usec", true), 42 PCONFDUMP(PIN_CONFIG_INPUT_ENABLE, "input enabled", NULL, false), 43 PCONFDUMP(PIN_CONFIG_INPUT_SCHMITT, "input schmitt trigger", NULL, false), 44 PCONFDUMP(PIN_CONFIG_INPUT_SCHMITT_ENABLE, "input schmitt enabled", NULL, false), 45 PCONFDUMP(PIN_CONFIG_LOW_POWER_MODE, "pin low power", "mode", true), 46 PCONFDUMP(PIN_CONFIG_OUTPUT_ENABLE, "output enabled", NULL, false), 47 PCONFDUMP(PIN_CONFIG_OUTPUT, "pin output", "level", true), 48 PCONFDUMP(PIN_CONFIG_POWER_SOURCE, "pin power source", "selector", true), 49 PCONFDUMP(PIN_CONFIG_SLEEP_HARDWARE_STATE, "sleep hardware state", NULL, false), 50 PCONFDUMP(PIN_CONFIG_SLEW_RATE, "slew rate", NULL, true), 51 PCONFDUMP(PIN_CONFIG_SKEW_DELAY, "skew delay", 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 { "skew-delay", PIN_CONFIG_SKEW_DELAY, 0 }, 185 }; 186 187 /** 188 * parse_dt_cfg() - Parse DT pinconf parameters 189 * @np: DT node 190 * @params: Array of describing generic parameters 191 * @count: Number of entries in @params 192 * @cfg: Array of parsed config options 193 * @ncfg: Number of entries in @cfg 194 * 195 * Parse the config options described in @params from @np and puts the result 196 * in @cfg. @cfg does not need to be empty, entries are added beginning at 197 * @ncfg. @ncfg is updated to reflect the number of entries after parsing. @cfg 198 * needs to have enough memory allocated to hold all possible entries. 199 */ 200 static void parse_dt_cfg(struct device_node *np, 201 const struct pinconf_generic_params *params, 202 unsigned int count, unsigned long *cfg, 203 unsigned int *ncfg) 204 { 205 int i; 206 207 for (i = 0; i < count; i++) { 208 u32 val; 209 int ret; 210 const struct pinconf_generic_params *par = ¶ms[i]; 211 212 ret = of_property_read_u32(np, par->property, &val); 213 214 /* property not found */ 215 if (ret == -EINVAL) 216 continue; 217 218 /* use default value, when no value is specified */ 219 if (ret) 220 val = par->default_value; 221 222 pr_debug("found %s with value %u\n", par->property, val); 223 cfg[*ncfg] = pinconf_to_config_packed(par->param, val); 224 (*ncfg)++; 225 } 226 } 227 228 /** 229 * pinconf_generic_parse_dt_config() 230 * parse the config properties into generic pinconfig values. 231 * @np: node containing the pinconfig properties 232 * @configs: array with nconfigs entries containing the generic pinconf values 233 * must be freed when no longer necessary. 234 * @nconfigs: umber of configurations 235 */ 236 int pinconf_generic_parse_dt_config(struct device_node *np, 237 struct pinctrl_dev *pctldev, 238 unsigned long **configs, 239 unsigned int *nconfigs) 240 { 241 unsigned long *cfg; 242 unsigned int max_cfg, ncfg = 0; 243 int ret; 244 245 if (!np) 246 return -EINVAL; 247 248 /* allocate a temporary array big enough to hold one of each option */ 249 max_cfg = ARRAY_SIZE(dt_params); 250 if (pctldev) 251 max_cfg += pctldev->desc->num_custom_params; 252 cfg = kcalloc(max_cfg, sizeof(*cfg), GFP_KERNEL); 253 if (!cfg) 254 return -ENOMEM; 255 256 parse_dt_cfg(np, dt_params, ARRAY_SIZE(dt_params), cfg, &ncfg); 257 if (pctldev && pctldev->desc->num_custom_params && 258 pctldev->desc->custom_params) 259 parse_dt_cfg(np, pctldev->desc->custom_params, 260 pctldev->desc->num_custom_params, cfg, &ncfg); 261 262 ret = 0; 263 264 /* no configs found at all */ 265 if (ncfg == 0) { 266 *configs = NULL; 267 *nconfigs = 0; 268 goto out; 269 } 270 271 /* 272 * Now limit the number of configs to the real number of 273 * found properties. 274 */ 275 *configs = kmemdup(cfg, ncfg * sizeof(unsigned long), GFP_KERNEL); 276 if (!*configs) { 277 ret = -ENOMEM; 278 goto out; 279 } 280 281 *nconfigs = ncfg; 282 283 out: 284 kfree(cfg); 285 return ret; 286 } 287 288 int pinconf_generic_dt_subnode_to_map(struct pinctrl_dev *pctldev, 289 struct device_node *np, struct pinctrl_map **map, 290 unsigned *reserved_maps, unsigned *num_maps, 291 enum pinctrl_map_type type) 292 { 293 int ret; 294 const char *function; 295 struct device *dev = pctldev->dev; 296 unsigned long *configs = NULL; 297 unsigned num_configs = 0; 298 unsigned reserve, strings_count; 299 struct property *prop; 300 const char *group; 301 const char *subnode_target_type = "pins"; 302 303 ret = of_property_count_strings(np, "pins"); 304 if (ret < 0) { 305 ret = of_property_count_strings(np, "groups"); 306 if (ret < 0) 307 /* skip this node; may contain config child nodes */ 308 return 0; 309 if (type == PIN_MAP_TYPE_INVALID) 310 type = PIN_MAP_TYPE_CONFIGS_GROUP; 311 subnode_target_type = "groups"; 312 } else { 313 if (type == PIN_MAP_TYPE_INVALID) 314 type = PIN_MAP_TYPE_CONFIGS_PIN; 315 } 316 strings_count = ret; 317 318 ret = of_property_read_string(np, "function", &function); 319 if (ret < 0) { 320 /* EINVAL=missing, which is fine since it's optional */ 321 if (ret != -EINVAL) 322 dev_err(dev, "%pOF: could not parse property function\n", 323 np); 324 function = NULL; 325 } 326 327 ret = pinconf_generic_parse_dt_config(np, pctldev, &configs, 328 &num_configs); 329 if (ret < 0) { 330 dev_err(dev, "%pOF: could not parse node property\n", np); 331 return ret; 332 } 333 334 reserve = 0; 335 if (function != NULL) 336 reserve++; 337 if (num_configs) 338 reserve++; 339 340 reserve *= strings_count; 341 342 ret = pinctrl_utils_reserve_map(pctldev, map, reserved_maps, 343 num_maps, reserve); 344 if (ret < 0) 345 goto exit; 346 347 of_property_for_each_string(np, subnode_target_type, prop, group) { 348 if (function) { 349 ret = pinctrl_utils_add_map_mux(pctldev, map, 350 reserved_maps, num_maps, group, 351 function); 352 if (ret < 0) 353 goto exit; 354 } 355 356 if (num_configs) { 357 ret = pinctrl_utils_add_map_configs(pctldev, map, 358 reserved_maps, num_maps, group, configs, 359 num_configs, type); 360 if (ret < 0) 361 goto exit; 362 } 363 } 364 ret = 0; 365 366 exit: 367 kfree(configs); 368 return ret; 369 } 370 EXPORT_SYMBOL_GPL(pinconf_generic_dt_subnode_to_map); 371 372 int pinconf_generic_dt_node_to_map(struct pinctrl_dev *pctldev, 373 struct device_node *np_config, struct pinctrl_map **map, 374 unsigned *num_maps, enum pinctrl_map_type type) 375 { 376 unsigned reserved_maps; 377 struct device_node *np; 378 int ret; 379 380 reserved_maps = 0; 381 *map = NULL; 382 *num_maps = 0; 383 384 ret = pinconf_generic_dt_subnode_to_map(pctldev, np_config, map, 385 &reserved_maps, num_maps, type); 386 if (ret < 0) 387 goto exit; 388 389 for_each_available_child_of_node(np_config, np) { 390 ret = pinconf_generic_dt_subnode_to_map(pctldev, np, map, 391 &reserved_maps, num_maps, type); 392 if (ret < 0) 393 goto exit; 394 } 395 return 0; 396 397 exit: 398 pinctrl_utils_free_map(pctldev, *map, *num_maps); 399 return ret; 400 } 401 EXPORT_SYMBOL_GPL(pinconf_generic_dt_node_to_map); 402 403 void pinconf_generic_dt_free_map(struct pinctrl_dev *pctldev, 404 struct pinctrl_map *map, 405 unsigned num_maps) 406 { 407 pinctrl_utils_free_map(pctldev, map, num_maps); 408 } 409 EXPORT_SYMBOL_GPL(pinconf_generic_dt_free_map); 410 411 #endif 412