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 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 { "input-debounce", PIN_CONFIG_INPUT_DEBOUNCE, 0 }, 171 { "input-disable", PIN_CONFIG_INPUT_ENABLE, 0 }, 172 { "input-enable", PIN_CONFIG_INPUT_ENABLE, 1 }, 173 { "input-schmitt", PIN_CONFIG_INPUT_SCHMITT, 0 }, 174 { "input-schmitt-disable", PIN_CONFIG_INPUT_SCHMITT_ENABLE, 0 }, 175 { "input-schmitt-enable", PIN_CONFIG_INPUT_SCHMITT_ENABLE, 1 }, 176 { "low-power-disable", PIN_CONFIG_LOW_POWER_MODE, 0 }, 177 { "low-power-enable", PIN_CONFIG_LOW_POWER_MODE, 1 }, 178 { "output-disable", PIN_CONFIG_OUTPUT_ENABLE, 0 }, 179 { "output-enable", PIN_CONFIG_OUTPUT_ENABLE, 1 }, 180 { "output-high", PIN_CONFIG_OUTPUT, 1, }, 181 { "output-low", PIN_CONFIG_OUTPUT, 0, }, 182 { "power-source", PIN_CONFIG_POWER_SOURCE, 0 }, 183 { "sleep-hardware-state", PIN_CONFIG_SLEEP_HARDWARE_STATE, 0 }, 184 { "slew-rate", PIN_CONFIG_SLEW_RATE, 0 }, 185 { "skew-delay", PIN_CONFIG_SKEW_DELAY, 0 }, 186 }; 187 188 /** 189 * parse_dt_cfg() - Parse DT pinconf parameters 190 * @np: DT node 191 * @params: Array of describing generic parameters 192 * @count: Number of entries in @params 193 * @cfg: Array of parsed config options 194 * @ncfg: Number of entries in @cfg 195 * 196 * Parse the config options described in @params from @np and puts the result 197 * in @cfg. @cfg does not need to be empty, entries are added beginning at 198 * @ncfg. @ncfg is updated to reflect the number of entries after parsing. @cfg 199 * needs to have enough memory allocated to hold all possible entries. 200 */ 201 static void parse_dt_cfg(struct device_node *np, 202 const struct pinconf_generic_params *params, 203 unsigned int count, unsigned long *cfg, 204 unsigned int *ncfg) 205 { 206 int i; 207 208 for (i = 0; i < count; i++) { 209 u32 val; 210 int ret; 211 const struct pinconf_generic_params *par = ¶ms[i]; 212 213 ret = of_property_read_u32(np, par->property, &val); 214 215 /* property not found */ 216 if (ret == -EINVAL) 217 continue; 218 219 /* use default value, when no value is specified */ 220 if (ret) 221 val = par->default_value; 222 223 pr_debug("found %s with value %u\n", par->property, val); 224 cfg[*ncfg] = pinconf_to_config_packed(par->param, val); 225 (*ncfg)++; 226 } 227 } 228 229 /** 230 * pinconf_generic_parse_dt_config() 231 * parse the config properties into generic pinconfig values. 232 * @np: node containing the pinconfig properties 233 * @configs: array with nconfigs entries containing the generic pinconf values 234 * must be freed when no longer necessary. 235 * @nconfigs: umber of configurations 236 */ 237 int pinconf_generic_parse_dt_config(struct device_node *np, 238 struct pinctrl_dev *pctldev, 239 unsigned long **configs, 240 unsigned int *nconfigs) 241 { 242 unsigned long *cfg; 243 unsigned int max_cfg, ncfg = 0; 244 int ret; 245 246 if (!np) 247 return -EINVAL; 248 249 /* allocate a temporary array big enough to hold one of each option */ 250 max_cfg = ARRAY_SIZE(dt_params); 251 if (pctldev) 252 max_cfg += pctldev->desc->num_custom_params; 253 cfg = kcalloc(max_cfg, sizeof(*cfg), GFP_KERNEL); 254 if (!cfg) 255 return -ENOMEM; 256 257 parse_dt_cfg(np, dt_params, ARRAY_SIZE(dt_params), cfg, &ncfg); 258 if (pctldev && pctldev->desc->num_custom_params && 259 pctldev->desc->custom_params) 260 parse_dt_cfg(np, pctldev->desc->custom_params, 261 pctldev->desc->num_custom_params, cfg, &ncfg); 262 263 ret = 0; 264 265 /* no configs found at all */ 266 if (ncfg == 0) { 267 *configs = NULL; 268 *nconfigs = 0; 269 goto out; 270 } 271 272 /* 273 * Now limit the number of configs to the real number of 274 * found properties. 275 */ 276 *configs = kmemdup(cfg, ncfg * sizeof(unsigned long), GFP_KERNEL); 277 if (!*configs) { 278 ret = -ENOMEM; 279 goto out; 280 } 281 282 *nconfigs = ncfg; 283 284 out: 285 kfree(cfg); 286 return ret; 287 } 288 289 int pinconf_generic_dt_subnode_to_map(struct pinctrl_dev *pctldev, 290 struct device_node *np, struct pinctrl_map **map, 291 unsigned *reserved_maps, unsigned *num_maps, 292 enum pinctrl_map_type type) 293 { 294 int ret; 295 const char *function; 296 struct device *dev = pctldev->dev; 297 unsigned long *configs = NULL; 298 unsigned num_configs = 0; 299 unsigned reserve, strings_count; 300 struct property *prop; 301 const char *group; 302 const char *subnode_target_type = "pins"; 303 304 ret = of_property_count_strings(np, "pins"); 305 if (ret < 0) { 306 ret = of_property_count_strings(np, "groups"); 307 if (ret < 0) 308 /* skip this node; may contain config child nodes */ 309 return 0; 310 if (type == PIN_MAP_TYPE_INVALID) 311 type = PIN_MAP_TYPE_CONFIGS_GROUP; 312 subnode_target_type = "groups"; 313 } else { 314 if (type == PIN_MAP_TYPE_INVALID) 315 type = PIN_MAP_TYPE_CONFIGS_PIN; 316 } 317 strings_count = ret; 318 319 ret = of_property_read_string(np, "function", &function); 320 if (ret < 0) { 321 /* EINVAL=missing, which is fine since it's optional */ 322 if (ret != -EINVAL) 323 dev_err(dev, "%pOF: could not parse property function\n", 324 np); 325 function = NULL; 326 } 327 328 ret = pinconf_generic_parse_dt_config(np, pctldev, &configs, 329 &num_configs); 330 if (ret < 0) { 331 dev_err(dev, "%pOF: could not parse node property\n", np); 332 return ret; 333 } 334 335 reserve = 0; 336 if (function != NULL) 337 reserve++; 338 if (num_configs) 339 reserve++; 340 341 reserve *= strings_count; 342 343 ret = pinctrl_utils_reserve_map(pctldev, map, reserved_maps, 344 num_maps, reserve); 345 if (ret < 0) 346 goto exit; 347 348 of_property_for_each_string(np, subnode_target_type, prop, group) { 349 if (function) { 350 ret = pinctrl_utils_add_map_mux(pctldev, map, 351 reserved_maps, num_maps, group, 352 function); 353 if (ret < 0) 354 goto exit; 355 } 356 357 if (num_configs) { 358 ret = pinctrl_utils_add_map_configs(pctldev, map, 359 reserved_maps, num_maps, group, configs, 360 num_configs, type); 361 if (ret < 0) 362 goto exit; 363 } 364 } 365 ret = 0; 366 367 exit: 368 kfree(configs); 369 return ret; 370 } 371 EXPORT_SYMBOL_GPL(pinconf_generic_dt_subnode_to_map); 372 373 int pinconf_generic_dt_node_to_map(struct pinctrl_dev *pctldev, 374 struct device_node *np_config, struct pinctrl_map **map, 375 unsigned *num_maps, enum pinctrl_map_type type) 376 { 377 unsigned reserved_maps; 378 struct device_node *np; 379 int ret; 380 381 reserved_maps = 0; 382 *map = NULL; 383 *num_maps = 0; 384 385 ret = pinconf_generic_dt_subnode_to_map(pctldev, np_config, map, 386 &reserved_maps, num_maps, type); 387 if (ret < 0) 388 goto exit; 389 390 for_each_available_child_of_node(np_config, np) { 391 ret = pinconf_generic_dt_subnode_to_map(pctldev, np, map, 392 &reserved_maps, num_maps, type); 393 if (ret < 0) 394 goto exit; 395 } 396 return 0; 397 398 exit: 399 pinctrl_utils_free_map(pctldev, *map, *num_maps); 400 return ret; 401 } 402 EXPORT_SYMBOL_GPL(pinconf_generic_dt_node_to_map); 403 404 void pinconf_generic_dt_free_map(struct pinctrl_dev *pctldev, 405 struct pinctrl_map *map, 406 unsigned num_maps) 407 { 408 pinctrl_utils_free_map(pctldev, map, num_maps); 409 } 410 EXPORT_SYMBOL_GPL(pinconf_generic_dt_free_map); 411 412 #endif 413