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 31 struct pin_config_item { 32 const enum pin_config_param param; 33 const char * const display; 34 const char * const format; 35 }; 36 37 #define PCONFDUMP(a, b, c) { .param = a, .display = b, .format = c } 38 39 static struct pin_config_item conf_items[] = { 40 PCONFDUMP(PIN_CONFIG_BIAS_DISABLE, "input bias disabled", NULL), 41 PCONFDUMP(PIN_CONFIG_BIAS_HIGH_IMPEDANCE, "input bias high impedance", NULL), 42 PCONFDUMP(PIN_CONFIG_BIAS_BUS_HOLD, "input bias bus hold", NULL), 43 PCONFDUMP(PIN_CONFIG_BIAS_PULL_UP, "input bias pull up", NULL), 44 PCONFDUMP(PIN_CONFIG_BIAS_PULL_DOWN, "input bias pull down", NULL), 45 PCONFDUMP(PIN_CONFIG_BIAS_PULL_PIN_DEFAULT, 46 "input bias pull to pin specific state", NULL), 47 PCONFDUMP(PIN_CONFIG_DRIVE_PUSH_PULL, "output drive push pull", NULL), 48 PCONFDUMP(PIN_CONFIG_DRIVE_OPEN_DRAIN, "output drive open drain", NULL), 49 PCONFDUMP(PIN_CONFIG_DRIVE_OPEN_SOURCE, "output drive open source", NULL), 50 PCONFDUMP(PIN_CONFIG_DRIVE_STRENGTH, "output drive strength", "mA"), 51 PCONFDUMP(PIN_CONFIG_INPUT_ENABLE, "input enabled", NULL), 52 PCONFDUMP(PIN_CONFIG_INPUT_SCHMITT_ENABLE, "input schmitt enabled", NULL), 53 PCONFDUMP(PIN_CONFIG_INPUT_SCHMITT, "input schmitt trigger", NULL), 54 PCONFDUMP(PIN_CONFIG_INPUT_DEBOUNCE, "input debounce", "usec"), 55 PCONFDUMP(PIN_CONFIG_POWER_SOURCE, "pin power source", "selector"), 56 PCONFDUMP(PIN_CONFIG_SLEW_RATE, "slew rate", NULL), 57 PCONFDUMP(PIN_CONFIG_LOW_POWER_MODE, "pin low power", "mode"), 58 PCONFDUMP(PIN_CONFIG_OUTPUT, "pin output", "level"), 59 }; 60 61 void pinconf_generic_dump_pin(struct pinctrl_dev *pctldev, 62 struct seq_file *s, unsigned pin) 63 { 64 const struct pinconf_ops *ops = pctldev->desc->confops; 65 int i; 66 67 if (!ops->is_generic) 68 return; 69 70 for (i = 0; i < ARRAY_SIZE(conf_items); i++) { 71 unsigned long config; 72 int ret; 73 74 /* We want to check out this parameter */ 75 config = pinconf_to_config_packed(conf_items[i].param, 0); 76 ret = pin_config_get_for_pin(pctldev, pin, &config); 77 /* These are legal errors */ 78 if (ret == -EINVAL || ret == -ENOTSUPP) 79 continue; 80 if (ret) { 81 seq_printf(s, "ERROR READING CONFIG SETTING %d ", i); 82 continue; 83 } 84 /* Space between multiple configs */ 85 seq_puts(s, " "); 86 seq_puts(s, conf_items[i].display); 87 /* Print unit if available */ 88 if (conf_items[i].format && 89 pinconf_to_config_argument(config) != 0) 90 seq_printf(s, " (%u %s)", 91 pinconf_to_config_argument(config), 92 conf_items[i].format); 93 } 94 } 95 96 void pinconf_generic_dump_group(struct pinctrl_dev *pctldev, 97 struct seq_file *s, const char *gname) 98 { 99 const struct pinconf_ops *ops = pctldev->desc->confops; 100 int i; 101 102 if (!ops->is_generic) 103 return; 104 105 for (i = 0; i < ARRAY_SIZE(conf_items); i++) { 106 unsigned long config; 107 int ret; 108 109 /* We want to check out this parameter */ 110 config = pinconf_to_config_packed(conf_items[i].param, 0); 111 ret = pin_config_group_get(dev_name(pctldev->dev), gname, 112 &config); 113 /* These are legal errors */ 114 if (ret == -EINVAL || ret == -ENOTSUPP) 115 continue; 116 if (ret) { 117 seq_printf(s, "ERROR READING CONFIG SETTING %d ", i); 118 continue; 119 } 120 /* Space between multiple configs */ 121 seq_puts(s, " "); 122 seq_puts(s, conf_items[i].display); 123 /* Print unit if available */ 124 if (conf_items[i].format && config != 0) 125 seq_printf(s, " (%u %s)", 126 pinconf_to_config_argument(config), 127 conf_items[i].format); 128 } 129 } 130 131 void pinconf_generic_dump_config(struct pinctrl_dev *pctldev, 132 struct seq_file *s, unsigned long config) 133 { 134 int i; 135 136 for (i = 0; i < ARRAY_SIZE(conf_items); i++) { 137 if (pinconf_to_config_param(config) != conf_items[i].param) 138 continue; 139 seq_printf(s, "%s: 0x%x", conf_items[i].display, 140 pinconf_to_config_argument(config)); 141 } 142 } 143 EXPORT_SYMBOL_GPL(pinconf_generic_dump_config); 144 #endif 145 146 #ifdef CONFIG_OF 147 struct pinconf_generic_dt_params { 148 const char * const property; 149 enum pin_config_param param; 150 u32 default_value; 151 }; 152 153 static struct pinconf_generic_dt_params dt_params[] = { 154 { "bias-disable", PIN_CONFIG_BIAS_DISABLE, 0 }, 155 { "bias-high-impedance", PIN_CONFIG_BIAS_HIGH_IMPEDANCE, 0 }, 156 { "bias-bus-hold", PIN_CONFIG_BIAS_BUS_HOLD, 0 }, 157 { "bias-pull-up", PIN_CONFIG_BIAS_PULL_UP, 1 }, 158 { "bias-pull-down", PIN_CONFIG_BIAS_PULL_DOWN, 1 }, 159 { "bias-pull-pin-default", PIN_CONFIG_BIAS_PULL_PIN_DEFAULT, 1 }, 160 { "drive-push-pull", PIN_CONFIG_DRIVE_PUSH_PULL, 0 }, 161 { "drive-open-drain", PIN_CONFIG_DRIVE_OPEN_DRAIN, 0 }, 162 { "drive-open-source", PIN_CONFIG_DRIVE_OPEN_SOURCE, 0 }, 163 { "drive-strength", PIN_CONFIG_DRIVE_STRENGTH, 0 }, 164 { "input-enable", PIN_CONFIG_INPUT_ENABLE, 1 }, 165 { "input-disable", PIN_CONFIG_INPUT_ENABLE, 0 }, 166 { "input-schmitt-enable", PIN_CONFIG_INPUT_SCHMITT_ENABLE, 1 }, 167 { "input-schmitt-disable", PIN_CONFIG_INPUT_SCHMITT_ENABLE, 0 }, 168 { "input-debounce", PIN_CONFIG_INPUT_DEBOUNCE, 0 }, 169 { "power-source", PIN_CONFIG_POWER_SOURCE, 0 }, 170 { "low-power-enable", PIN_CONFIG_LOW_POWER_MODE, 1 }, 171 { "low-power-disable", PIN_CONFIG_LOW_POWER_MODE, 0 }, 172 { "output-low", PIN_CONFIG_OUTPUT, 0, }, 173 { "output-high", PIN_CONFIG_OUTPUT, 1, }, 174 { "slew-rate", PIN_CONFIG_SLEW_RATE, 0}, 175 }; 176 177 /** 178 * pinconf_generic_parse_dt_config() 179 * parse the config properties into generic pinconfig values. 180 * @np: node containing the pinconfig properties 181 * @configs: array with nconfigs entries containing the generic pinconf values 182 * @nconfigs: umber of configurations 183 */ 184 int pinconf_generic_parse_dt_config(struct device_node *np, 185 unsigned long **configs, 186 unsigned int *nconfigs) 187 { 188 unsigned long *cfg; 189 unsigned int ncfg = 0; 190 int ret; 191 int i; 192 u32 val; 193 194 if (!np) 195 return -EINVAL; 196 197 /* allocate a temporary array big enough to hold one of each option */ 198 cfg = kzalloc(sizeof(*cfg) * ARRAY_SIZE(dt_params), GFP_KERNEL); 199 if (!cfg) 200 return -ENOMEM; 201 202 for (i = 0; i < ARRAY_SIZE(dt_params); i++) { 203 struct pinconf_generic_dt_params *par = &dt_params[i]; 204 ret = of_property_read_u32(np, par->property, &val); 205 206 /* property not found */ 207 if (ret == -EINVAL) 208 continue; 209 210 /* use default value, when no value is specified */ 211 if (ret) 212 val = par->default_value; 213 214 pr_debug("found %s with value %u\n", par->property, val); 215 cfg[ncfg] = pinconf_to_config_packed(par->param, val); 216 ncfg++; 217 } 218 219 ret = 0; 220 221 /* no configs found at all */ 222 if (ncfg == 0) { 223 *configs = NULL; 224 *nconfigs = 0; 225 goto out; 226 } 227 228 /* 229 * Now limit the number of configs to the real number of 230 * found properties. 231 */ 232 *configs = kmemdup(cfg, ncfg * sizeof(unsigned long), GFP_KERNEL); 233 if (!*configs) { 234 ret = -ENOMEM; 235 goto out; 236 } 237 238 *nconfigs = ncfg; 239 240 out: 241 kfree(cfg); 242 return ret; 243 } 244 245 int pinconf_generic_dt_subnode_to_map(struct pinctrl_dev *pctldev, 246 struct device_node *np, struct pinctrl_map **map, 247 unsigned *reserved_maps, unsigned *num_maps, 248 enum pinctrl_map_type type) 249 { 250 int ret; 251 const char *function; 252 struct device *dev = pctldev->dev; 253 unsigned long *configs = NULL; 254 unsigned num_configs = 0; 255 unsigned reserve; 256 struct property *prop; 257 const char *group; 258 259 ret = of_property_read_string(np, "function", &function); 260 if (ret < 0) { 261 /* EINVAL=missing, which is fine since it's optional */ 262 if (ret != -EINVAL) 263 dev_err(dev, "could not parse property function\n"); 264 function = NULL; 265 } 266 267 ret = pinconf_generic_parse_dt_config(np, &configs, &num_configs); 268 if (ret < 0) { 269 dev_err(dev, "could not parse node property\n"); 270 return ret; 271 } 272 273 reserve = 0; 274 if (function != NULL) 275 reserve++; 276 if (num_configs) 277 reserve++; 278 ret = of_property_count_strings(np, "pins"); 279 if (ret < 0) { 280 dev_err(dev, "could not parse property pins\n"); 281 goto exit; 282 } 283 reserve *= ret; 284 285 ret = pinctrl_utils_reserve_map(pctldev, map, reserved_maps, 286 num_maps, reserve); 287 if (ret < 0) 288 goto exit; 289 290 of_property_for_each_string(np, "pins", prop, group) { 291 if (function) { 292 ret = pinctrl_utils_add_map_mux(pctldev, map, 293 reserved_maps, num_maps, group, 294 function); 295 if (ret < 0) 296 goto exit; 297 } 298 299 if (num_configs) { 300 ret = pinctrl_utils_add_map_configs(pctldev, map, 301 reserved_maps, num_maps, group, configs, 302 num_configs, type); 303 if (ret < 0) 304 goto exit; 305 } 306 } 307 ret = 0; 308 309 exit: 310 kfree(configs); 311 return ret; 312 } 313 EXPORT_SYMBOL_GPL(pinconf_generic_dt_subnode_to_map); 314 315 int pinconf_generic_dt_node_to_map(struct pinctrl_dev *pctldev, 316 struct device_node *np_config, struct pinctrl_map **map, 317 unsigned *num_maps, enum pinctrl_map_type type) 318 { 319 unsigned reserved_maps; 320 struct device_node *np; 321 int ret; 322 323 reserved_maps = 0; 324 *map = NULL; 325 *num_maps = 0; 326 327 for_each_child_of_node(np_config, np) { 328 ret = pinconf_generic_dt_subnode_to_map(pctldev, np, map, 329 &reserved_maps, num_maps, type); 330 if (ret < 0) { 331 pinctrl_utils_dt_free_map(pctldev, *map, *num_maps); 332 return ret; 333 } 334 } 335 return 0; 336 } 337 EXPORT_SYMBOL_GPL(pinconf_generic_dt_node_to_map); 338 339 #endif 340