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