1f141ed65SGrant Likely /* 2f141ed65SGrant Likely * OF helpers for the GPIO API 3f141ed65SGrant Likely * 4f141ed65SGrant Likely * Copyright (c) 2007-2008 MontaVista Software, Inc. 5f141ed65SGrant Likely * 6f141ed65SGrant Likely * Author: Anton Vorontsov <avorontsov@ru.mvista.com> 7f141ed65SGrant Likely * 8f141ed65SGrant Likely * This program is free software; you can redistribute it and/or modify 9f141ed65SGrant Likely * it under the terms of the GNU General Public License as published by 10f141ed65SGrant Likely * the Free Software Foundation; either version 2 of the License, or 11f141ed65SGrant Likely * (at your option) any later version. 12f141ed65SGrant Likely */ 13f141ed65SGrant Likely 14f141ed65SGrant Likely #include <linux/device.h> 15bea4dbeeSSachin Kamat #include <linux/err.h> 16f141ed65SGrant Likely #include <linux/errno.h> 17f141ed65SGrant Likely #include <linux/module.h> 18f141ed65SGrant Likely #include <linux/io.h> 19af8b6375SAlexandre Courbot #include <linux/gpio/consumer.h> 20f141ed65SGrant Likely #include <linux/of.h> 21f141ed65SGrant Likely #include <linux/of_address.h> 22f141ed65SGrant Likely #include <linux/of_gpio.h> 23f23f1516SShiraz Hashim #include <linux/pinctrl/pinctrl.h> 24f141ed65SGrant Likely #include <linux/slab.h> 25f141ed65SGrant Likely 261bd6b601SAlexandre Courbot #include "gpiolib.h" 27af8b6375SAlexandre Courbot 280df2c999SDong Aisheng /* Private data structure for of_gpiochip_find_and_xlate */ 293d0f7cf0SGrant Likely struct gg_data { 303d0f7cf0SGrant Likely enum of_gpio_flags *flags; 313d0f7cf0SGrant Likely struct of_phandle_args gpiospec; 323d0f7cf0SGrant Likely 33af8b6375SAlexandre Courbot struct gpio_desc *out_gpio; 343d0f7cf0SGrant Likely }; 353d0f7cf0SGrant Likely 363d0f7cf0SGrant Likely /* Private function for resolving node pointer to gpio_chip */ 373d0f7cf0SGrant Likely static int of_gpiochip_find_and_xlate(struct gpio_chip *gc, void *data) 383d0f7cf0SGrant Likely { 393d0f7cf0SGrant Likely struct gg_data *gg_data = data; 403d0f7cf0SGrant Likely int ret; 413d0f7cf0SGrant Likely 423d0f7cf0SGrant Likely if ((gc->of_node != gg_data->gpiospec.np) || 433d0f7cf0SGrant Likely (gc->of_gpio_n_cells != gg_data->gpiospec.args_count) || 443d0f7cf0SGrant Likely (!gc->of_xlate)) 453d0f7cf0SGrant Likely return false; 463d0f7cf0SGrant Likely 473d0f7cf0SGrant Likely ret = gc->of_xlate(gc, &gg_data->gpiospec, gg_data->flags); 487b8792bbSHans Holmberg if (ret < 0) { 497b8792bbSHans Holmberg /* We've found the gpio chip, but the translation failed. 507b8792bbSHans Holmberg * Return true to stop looking and return the translation 517b8792bbSHans Holmberg * error via out_gpio 527b8792bbSHans Holmberg */ 537b8792bbSHans Holmberg gg_data->out_gpio = ERR_PTR(ret); 547b8792bbSHans Holmberg return true; 557b8792bbSHans Holmberg } 563d0f7cf0SGrant Likely 57ccd9726eSLinus Walleij gg_data->out_gpio = gpiochip_get_desc(gc, ret); 583d0f7cf0SGrant Likely return true; 593d0f7cf0SGrant Likely } 603d0f7cf0SGrant Likely 61f141ed65SGrant Likely /** 62af8b6375SAlexandre Courbot * of_get_named_gpiod_flags() - Get a GPIO descriptor and flags for GPIO API 63f141ed65SGrant Likely * @np: device node to get GPIO from 64f141ed65SGrant Likely * @propname: property name containing gpio specifier(s) 65f141ed65SGrant Likely * @index: index of the GPIO 66f141ed65SGrant Likely * @flags: a flags pointer to fill in 67f141ed65SGrant Likely * 68af8b6375SAlexandre Courbot * Returns GPIO descriptor to use with Linux GPIO API, or one of the errno 69f141ed65SGrant Likely * value on the error condition. If @flags is not NULL the function also fills 70f141ed65SGrant Likely * in flags for the GPIO. 71f141ed65SGrant Likely */ 72af8b6375SAlexandre Courbot struct gpio_desc *of_get_named_gpiod_flags(struct device_node *np, 73af8b6375SAlexandre Courbot const char *propname, int index, enum of_gpio_flags *flags) 74f141ed65SGrant Likely { 754fbb0022SRoland Stigge /* Return -EPROBE_DEFER to support probe() functions to be called 764fbb0022SRoland Stigge * later when the GPIO actually becomes available 774fbb0022SRoland Stigge */ 78af8b6375SAlexandre Courbot struct gg_data gg_data = { 79af8b6375SAlexandre Courbot .flags = flags, 80af8b6375SAlexandre Courbot .out_gpio = ERR_PTR(-EPROBE_DEFER) 81af8b6375SAlexandre Courbot }; 82f141ed65SGrant Likely int ret; 83f141ed65SGrant Likely 843d0f7cf0SGrant Likely /* .of_xlate might decide to not fill in the flags, so clear it. */ 85f141ed65SGrant Likely if (flags) 86f141ed65SGrant Likely *flags = 0; 87f141ed65SGrant Likely 883d0f7cf0SGrant Likely ret = of_parse_phandle_with_args(np, propname, "#gpio-cells", index, 893d0f7cf0SGrant Likely &gg_data.gpiospec); 903d0f7cf0SGrant Likely if (ret) { 9185ea29acSTushar Behera pr_debug("%s: can't parse '%s' property of node '%s[%d]'\n", 9285ea29acSTushar Behera __func__, propname, np->full_name, index); 93af8b6375SAlexandre Courbot return ERR_PTR(ret); 943d0f7cf0SGrant Likely } 95f141ed65SGrant Likely 963d0f7cf0SGrant Likely gpiochip_find(&gg_data, of_gpiochip_find_and_xlate); 973d0f7cf0SGrant Likely 983d0f7cf0SGrant Likely of_node_put(gg_data.gpiospec.np); 9985ea29acSTushar Behera pr_debug("%s: parsed '%s' property of node '%s[%d]' - status (%d)\n", 10085ea29acSTushar Behera __func__, propname, np->full_name, index, 101bea4dbeeSSachin Kamat PTR_ERR_OR_ZERO(gg_data.out_gpio)); 1023d0f7cf0SGrant Likely return gg_data.out_gpio; 103f141ed65SGrant Likely } 104f141ed65SGrant Likely 105f01d9075SAlexandre Courbot int of_get_named_gpio_flags(struct device_node *np, const char *list_name, 106f01d9075SAlexandre Courbot int index, enum of_gpio_flags *flags) 107f01d9075SAlexandre Courbot { 108f01d9075SAlexandre Courbot struct gpio_desc *desc; 109f01d9075SAlexandre Courbot 110f01d9075SAlexandre Courbot desc = of_get_named_gpiod_flags(np, list_name, index, flags); 111f01d9075SAlexandre Courbot 112f01d9075SAlexandre Courbot if (IS_ERR(desc)) 113f01d9075SAlexandre Courbot return PTR_ERR(desc); 114f01d9075SAlexandre Courbot else 115f01d9075SAlexandre Courbot return desc_to_gpio(desc); 116f01d9075SAlexandre Courbot } 117f01d9075SAlexandre Courbot EXPORT_SYMBOL(of_get_named_gpio_flags); 118f01d9075SAlexandre Courbot 119f141ed65SGrant Likely /** 120f141ed65SGrant Likely * of_gpio_simple_xlate - translate gpio_spec to the GPIO number and flags 121f141ed65SGrant Likely * @gc: pointer to the gpio_chip structure 122f141ed65SGrant Likely * @np: device node of the GPIO chip 123f141ed65SGrant Likely * @gpio_spec: gpio specifier as found in the device tree 124f141ed65SGrant Likely * @flags: a flags pointer to fill in 125f141ed65SGrant Likely * 126f141ed65SGrant Likely * This is simple translation function, suitable for the most 1:1 mapped 127f141ed65SGrant Likely * gpio chips. This function performs only one sanity check: whether gpio 128f141ed65SGrant Likely * is less than ngpios (that is specified in the gpio_chip). 129f141ed65SGrant Likely */ 130f141ed65SGrant Likely int of_gpio_simple_xlate(struct gpio_chip *gc, 131f141ed65SGrant Likely const struct of_phandle_args *gpiospec, u32 *flags) 132f141ed65SGrant Likely { 133f141ed65SGrant Likely /* 134f141ed65SGrant Likely * We're discouraging gpio_cells < 2, since that way you'll have to 135f141ed65SGrant Likely * write your own xlate function (that will have to retrive the GPIO 136f141ed65SGrant Likely * number and the flags from a single gpio cell -- this is possible, 137f141ed65SGrant Likely * but not recommended). 138f141ed65SGrant Likely */ 139f141ed65SGrant Likely if (gc->of_gpio_n_cells < 2) { 140f141ed65SGrant Likely WARN_ON(1); 141f141ed65SGrant Likely return -EINVAL; 142f141ed65SGrant Likely } 143f141ed65SGrant Likely 144f141ed65SGrant Likely if (WARN_ON(gpiospec->args_count < gc->of_gpio_n_cells)) 145f141ed65SGrant Likely return -EINVAL; 146f141ed65SGrant Likely 1477b96c686SGrant Likely if (gpiospec->args[0] >= gc->ngpio) 148f141ed65SGrant Likely return -EINVAL; 149f141ed65SGrant Likely 150f141ed65SGrant Likely if (flags) 151f141ed65SGrant Likely *flags = gpiospec->args[1]; 152f141ed65SGrant Likely 153f141ed65SGrant Likely return gpiospec->args[0]; 154f141ed65SGrant Likely } 155f141ed65SGrant Likely EXPORT_SYMBOL(of_gpio_simple_xlate); 156f141ed65SGrant Likely 157f141ed65SGrant Likely /** 158f141ed65SGrant Likely * of_mm_gpiochip_add - Add memory mapped GPIO chip (bank) 159f141ed65SGrant Likely * @np: device node of the GPIO chip 160f141ed65SGrant Likely * @mm_gc: pointer to the of_mm_gpio_chip allocated structure 161f141ed65SGrant Likely * 162f141ed65SGrant Likely * To use this function you should allocate and fill mm_gc with: 163f141ed65SGrant Likely * 164f141ed65SGrant Likely * 1) In the gpio_chip structure: 165f141ed65SGrant Likely * - all the callbacks 166f141ed65SGrant Likely * - of_gpio_n_cells 167f141ed65SGrant Likely * - of_xlate callback (optional) 168f141ed65SGrant Likely * 169f141ed65SGrant Likely * 3) In the of_mm_gpio_chip structure: 170f141ed65SGrant Likely * - save_regs callback (optional) 171f141ed65SGrant Likely * 172f141ed65SGrant Likely * If succeeded, this function will map bank's memory and will 173f141ed65SGrant Likely * do all necessary work for you. Then you'll able to use .regs 174f141ed65SGrant Likely * to manage GPIOs from the callbacks. 175f141ed65SGrant Likely */ 176f141ed65SGrant Likely int of_mm_gpiochip_add(struct device_node *np, 177f141ed65SGrant Likely struct of_mm_gpio_chip *mm_gc) 178f141ed65SGrant Likely { 179f141ed65SGrant Likely int ret = -ENOMEM; 180f141ed65SGrant Likely struct gpio_chip *gc = &mm_gc->gc; 181f141ed65SGrant Likely 182f141ed65SGrant Likely gc->label = kstrdup(np->full_name, GFP_KERNEL); 183f141ed65SGrant Likely if (!gc->label) 184f141ed65SGrant Likely goto err0; 185f141ed65SGrant Likely 186f141ed65SGrant Likely mm_gc->regs = of_iomap(np, 0); 187f141ed65SGrant Likely if (!mm_gc->regs) 188f141ed65SGrant Likely goto err1; 189f141ed65SGrant Likely 190f141ed65SGrant Likely gc->base = -1; 191f141ed65SGrant Likely 192f141ed65SGrant Likely if (mm_gc->save_regs) 193f141ed65SGrant Likely mm_gc->save_regs(mm_gc); 194f141ed65SGrant Likely 195f141ed65SGrant Likely mm_gc->gc.of_node = np; 196f141ed65SGrant Likely 197f141ed65SGrant Likely ret = gpiochip_add(gc); 198f141ed65SGrant Likely if (ret) 199f141ed65SGrant Likely goto err2; 200f141ed65SGrant Likely 201f141ed65SGrant Likely return 0; 202f141ed65SGrant Likely err2: 203f141ed65SGrant Likely iounmap(mm_gc->regs); 204f141ed65SGrant Likely err1: 205f141ed65SGrant Likely kfree(gc->label); 206f141ed65SGrant Likely err0: 207f141ed65SGrant Likely pr_err("%s: GPIO chip registration failed with status %d\n", 208f141ed65SGrant Likely np->full_name, ret); 209f141ed65SGrant Likely return ret; 210f141ed65SGrant Likely } 211f141ed65SGrant Likely EXPORT_SYMBOL(of_mm_gpiochip_add); 212f141ed65SGrant Likely 213f23f1516SShiraz Hashim #ifdef CONFIG_PINCTRL 214167c1af9SLinus Walleij static void of_gpiochip_add_pin_range(struct gpio_chip *chip) 215f23f1516SShiraz Hashim { 216f23f1516SShiraz Hashim struct device_node *np = chip->of_node; 217f23f1516SShiraz Hashim struct of_phandle_args pinspec; 2181e63d7b9SLinus Walleij struct pinctrl_dev *pctldev; 219f23f1516SShiraz Hashim int index = 0, ret; 220586a87e6SChristian Ruppert const char *name; 221586a87e6SChristian Ruppert static const char group_names_propname[] = "gpio-ranges-group-names"; 222586a87e6SChristian Ruppert struct property *group_names; 223f23f1516SShiraz Hashim 224f23f1516SShiraz Hashim if (!np) 225f23f1516SShiraz Hashim return; 226f23f1516SShiraz Hashim 227586a87e6SChristian Ruppert group_names = of_find_property(np, group_names_propname, NULL); 228586a87e6SChristian Ruppert 229ad4e1a7cSHaojian Zhuang for (;; index++) { 230d9fe0039SStephen Warren ret = of_parse_phandle_with_fixed_args(np, "gpio-ranges", 3, 231d9fe0039SStephen Warren index, &pinspec); 232f23f1516SShiraz Hashim if (ret) 233f23f1516SShiraz Hashim break; 234f23f1516SShiraz Hashim 2351e63d7b9SLinus Walleij pctldev = of_pinctrl_get(pinspec.np); 2361e63d7b9SLinus Walleij if (!pctldev) 237f23f1516SShiraz Hashim break; 238f23f1516SShiraz Hashim 239586a87e6SChristian Ruppert if (pinspec.args[2]) { 240586a87e6SChristian Ruppert if (group_names) { 241586a87e6SChristian Ruppert ret = of_property_read_string_index(np, 242586a87e6SChristian Ruppert group_names_propname, 243586a87e6SChristian Ruppert index, &name); 244586a87e6SChristian Ruppert if (strlen(name)) { 245586a87e6SChristian Ruppert pr_err("%s: Group name of numeric GPIO ranges must be the empty string.\n", 246586a87e6SChristian Ruppert np->full_name); 247586a87e6SChristian Ruppert break; 248586a87e6SChristian Ruppert } 249586a87e6SChristian Ruppert } 250586a87e6SChristian Ruppert /* npins != 0: linear range */ 2511e63d7b9SLinus Walleij ret = gpiochip_add_pin_range(chip, 252ef5e3eefSHaojian Zhuang pinctrl_dev_get_devname(pctldev), 2531e63d7b9SLinus Walleij pinspec.args[0], 25486853c83SHaojian Zhuang pinspec.args[1], 25586853c83SHaojian Zhuang pinspec.args[2]); 2561e63d7b9SLinus Walleij if (ret) 2571e63d7b9SLinus Walleij break; 258586a87e6SChristian Ruppert } else { 259586a87e6SChristian Ruppert /* npins == 0: special range */ 260586a87e6SChristian Ruppert if (pinspec.args[1]) { 261586a87e6SChristian Ruppert pr_err("%s: Illegal gpio-range format.\n", 262586a87e6SChristian Ruppert np->full_name); 263586a87e6SChristian Ruppert break; 264586a87e6SChristian Ruppert } 265586a87e6SChristian Ruppert 266586a87e6SChristian Ruppert if (!group_names) { 267586a87e6SChristian Ruppert pr_err("%s: GPIO group range requested but no %s property.\n", 268586a87e6SChristian Ruppert np->full_name, group_names_propname); 269586a87e6SChristian Ruppert break; 270586a87e6SChristian Ruppert } 271586a87e6SChristian Ruppert 272586a87e6SChristian Ruppert ret = of_property_read_string_index(np, 273586a87e6SChristian Ruppert group_names_propname, 274586a87e6SChristian Ruppert index, &name); 275586a87e6SChristian Ruppert if (ret) 276586a87e6SChristian Ruppert break; 277586a87e6SChristian Ruppert 278586a87e6SChristian Ruppert if (!strlen(name)) { 279586a87e6SChristian Ruppert pr_err("%s: Group name of GPIO group range cannot be the empty string.\n", 280586a87e6SChristian Ruppert np->full_name); 281586a87e6SChristian Ruppert break; 282586a87e6SChristian Ruppert } 283586a87e6SChristian Ruppert 284586a87e6SChristian Ruppert ret = gpiochip_add_pingroup_range(chip, pctldev, 285586a87e6SChristian Ruppert pinspec.args[0], name); 286586a87e6SChristian Ruppert if (ret) 287586a87e6SChristian Ruppert break; 288586a87e6SChristian Ruppert } 289ad4e1a7cSHaojian Zhuang } 290f23f1516SShiraz Hashim } 291f23f1516SShiraz Hashim 292f23f1516SShiraz Hashim #else 293167c1af9SLinus Walleij static void of_gpiochip_add_pin_range(struct gpio_chip *chip) {} 294f23f1516SShiraz Hashim #endif 295f23f1516SShiraz Hashim 296f141ed65SGrant Likely void of_gpiochip_add(struct gpio_chip *chip) 297f141ed65SGrant Likely { 298f141ed65SGrant Likely if ((!chip->of_node) && (chip->dev)) 299f141ed65SGrant Likely chip->of_node = chip->dev->of_node; 300f141ed65SGrant Likely 301f141ed65SGrant Likely if (!chip->of_node) 302f141ed65SGrant Likely return; 303f141ed65SGrant Likely 304f141ed65SGrant Likely if (!chip->of_xlate) { 305f141ed65SGrant Likely chip->of_gpio_n_cells = 2; 306f141ed65SGrant Likely chip->of_xlate = of_gpio_simple_xlate; 307f141ed65SGrant Likely } 308f141ed65SGrant Likely 309f23f1516SShiraz Hashim of_gpiochip_add_pin_range(chip); 310f141ed65SGrant Likely of_node_get(chip->of_node); 311f141ed65SGrant Likely } 312f141ed65SGrant Likely 313f141ed65SGrant Likely void of_gpiochip_remove(struct gpio_chip *chip) 314f141ed65SGrant Likely { 315e93fa3f2SLinus Walleij gpiochip_remove_pin_ranges(chip); 316f141ed65SGrant Likely of_node_put(chip->of_node); 317f141ed65SGrant Likely } 318