pinconf-generic.c 12 KB

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