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1// SPDX-License-Identifier: GPL-2.0+2/*3 * OF helpers for the GPIO API4 *5 * Copyright (c) 2007-2008  MontaVista Software, Inc.6 *7 * Author: Anton Vorontsov <avorontsov@ru.mvista.com>8 */9 10#include <linux/device.h>11#include <linux/err.h>12#include <linux/errno.h>13#include <linux/io.h>14#include <linux/module.h>15#include <linux/of.h>16#include <linux/of_address.h>17#include <linux/of_gpio.h>18#include <linux/pinctrl/pinctrl.h>19#include <linux/slab.h>20#include <linux/string.h>21 22#include <linux/gpio/consumer.h>23#include <linux/gpio/machine.h>24 25#include "gpiolib.h"26#include "gpiolib-of.h"27 28/*29 * This is Linux-specific flags. By default controllers' and Linux' mapping30 * match, but GPIO controllers are free to translate their own flags to31 * Linux-specific in their .xlate callback. Though, 1:1 mapping is recommended.32 */33enum of_gpio_flags {34	OF_GPIO_ACTIVE_LOW = 0x1,35	OF_GPIO_SINGLE_ENDED = 0x2,36	OF_GPIO_OPEN_DRAIN = 0x4,37	OF_GPIO_TRANSITORY = 0x8,38	OF_GPIO_PULL_UP = 0x10,39	OF_GPIO_PULL_DOWN = 0x20,40	OF_GPIO_PULL_DISABLE = 0x40,41};42 43/**44 * of_gpio_named_count() - Count GPIOs for a device45 * @np:		device node to count GPIOs for46 * @propname:	property name containing gpio specifier(s)47 *48 * The function returns the count of GPIOs specified for a node.49 * NOTE: The empty GPIO specifiers count too.50 *51 * Returns:52 * Either number of GPIOs defined in the property, or53 * *  %-EINVAL for an incorrectly formed "gpios" property, or54 * *  %-ENOENT for a missing "gpios" property.55 *56 * Example::57 *58 *     gpios = <059 *              &gpio1 1 260 *              061 *              &gpio2 3 4>;62 *63 * The above example defines four GPIOs, two of which are not specified.64 * This function will return '4'65 */66static int of_gpio_named_count(const struct device_node *np,67			       const char *propname)68{69	return of_count_phandle_with_args(np, propname, "#gpio-cells");70}71 72/**73 * of_gpio_spi_cs_get_count() - special GPIO counting for SPI74 * @np:    Consuming device node75 * @con_id: Function within the GPIO consumer76 *77 * Some elder GPIO controllers need special quirks. Currently we handle78 * the Freescale and PPC GPIO controller with bindings that doesn't use the79 * established "cs-gpios" for chip selects but instead rely on80 * "gpios" for the chip select lines. If we detect this, we redirect81 * the counting of "cs-gpios" to count "gpios" transparent to the82 * driver.83 *84 * Returns:85 * Either number of GPIOs defined in the property, or86 * *  %-EINVAL for an incorrectly formed "gpios" property, or87 * *  %-ENOENT for a missing "gpios" property.88 */89static int of_gpio_spi_cs_get_count(const struct device_node *np,90				    const char *con_id)91{92	if (!IS_ENABLED(CONFIG_SPI_MASTER))93		return 0;94	if (!con_id || strcmp(con_id, "cs"))95		return 0;96	if (!of_device_is_compatible(np, "fsl,spi") &&97	    !of_device_is_compatible(np, "aeroflexgaisler,spictrl") &&98	    !of_device_is_compatible(np, "ibm,ppc4xx-spi"))99		return 0;100	return of_gpio_named_count(np, "gpios");101}102 103int of_gpio_count(const struct fwnode_handle *fwnode, const char *con_id)104{105	const struct device_node *np = to_of_node(fwnode);106	int ret;107	char propname[32];108 109	ret = of_gpio_spi_cs_get_count(np, con_id);110	if (ret > 0)111		return ret;112 113	for_each_gpio_property_name(propname, con_id) {114		ret = of_gpio_named_count(np, propname);115		if (ret > 0)116			break;117	}118	return ret ? ret : -ENOENT;119}120 121static int of_gpiochip_match_node_and_xlate(struct gpio_chip *chip,122					    const void *data)123{124	const struct of_phandle_args *gpiospec = data;125 126	return device_match_of_node(&chip->gpiodev->dev, gpiospec->np) &&127				chip->of_xlate &&128				chip->of_xlate(chip, gpiospec, NULL) >= 0;129}130 131static struct gpio_device *132of_find_gpio_device_by_xlate(const struct of_phandle_args *gpiospec)133{134	return gpio_device_find(gpiospec, of_gpiochip_match_node_and_xlate);135}136 137static struct gpio_desc *of_xlate_and_get_gpiod_flags(struct gpio_chip *chip,138					struct of_phandle_args *gpiospec,139					enum of_gpio_flags *flags)140{141	int ret;142 143	if (chip->of_gpio_n_cells != gpiospec->args_count)144		return ERR_PTR(-EINVAL);145 146	ret = chip->of_xlate(chip, gpiospec, flags);147	if (ret < 0)148		return ERR_PTR(ret);149 150	return gpiochip_get_desc(chip, ret);151}152 153/*154 * Overrides stated polarity of a gpio line and warns when there is a155 * discrepancy.156 */157static void of_gpio_quirk_polarity(const struct device_node *np,158				   bool active_high,159				   enum of_gpio_flags *flags)160{161	if (active_high) {162		if (*flags & OF_GPIO_ACTIVE_LOW) {163			pr_warn("%s GPIO handle specifies active low - ignored\n",164				of_node_full_name(np));165			*flags &= ~OF_GPIO_ACTIVE_LOW;166		}167	} else {168		if (!(*flags & OF_GPIO_ACTIVE_LOW))169			pr_info("%s enforce active low on GPIO handle\n",170				of_node_full_name(np));171		*flags |= OF_GPIO_ACTIVE_LOW;172	}173}174 175/*176 * This quirk does static polarity overrides in cases where existing177 * DTS specified incorrect polarity.178 */179static void of_gpio_try_fixup_polarity(const struct device_node *np,180				       const char *propname,181				       enum of_gpio_flags *flags)182{183	static const struct {184		const char *compatible;185		const char *propname;186		bool active_high;187	} gpios[] = {188#if IS_ENABLED(CONFIG_LCD_HX8357)189		/*190		 * Himax LCD controllers used incorrectly named191		 * "gpios-reset" property and also specified wrong192		 * polarity.193		 */194		{ "himax,hx8357",	"gpios-reset",	false },195		{ "himax,hx8369",	"gpios-reset",	false },196		/*197		 * The rb-gpios semantics was undocumented and qi,lb60 (along with198		 * the ingenic driver) got it wrong. The active state encodes the199		 * NAND ready state, which is high level. Since there's no signal200		 * inverter on this board, it should be active-high. Let's fix that201		 * here for older DTs so we can re-use the generic nand_gpio_waitrdy()202		 * helper, and be consistent with what other drivers do.203		 */204		{ "qi,lb60",		"rb-gpios",	true },205#endif206#if IS_ENABLED(CONFIG_PCI_LANTIQ)207		/*208		 * According to the PCI specification, the RST# pin is an209		 * active-low signal. However, most of the device trees that210		 * have been widely used for a long time incorrectly describe211		 * reset GPIO as active-high, and were also using wrong name212		 * for the property.213		 */214		{ "lantiq,pci-xway",	"gpio-reset",	false },215#endif216#if IS_ENABLED(CONFIG_TOUCHSCREEN_TSC2005)217		/*218		 * DTS for Nokia N900 incorrectly specified "active high"219		 * polarity for the reset line, while the chip actually220		 * treats it as "active low".221		 */222		{ "ti,tsc2005",		"reset-gpios",	false },223#endif224	};225	unsigned int i;226 227	for (i = 0; i < ARRAY_SIZE(gpios); i++) {228		if (of_device_is_compatible(np, gpios[i].compatible) &&229		    !strcmp(propname, gpios[i].propname)) {230			of_gpio_quirk_polarity(np, gpios[i].active_high, flags);231			break;232		}233	}234}235 236static void of_gpio_set_polarity_by_property(const struct device_node *np,237					     const char *propname,238					     enum of_gpio_flags *flags)239{240	const struct device_node *np_compat = np;241	const struct device_node *np_propname = np;242	static const struct {243		const char *compatible;244		const char *gpio_propname;245		const char *polarity_propname;246	} gpios[] = {247#if IS_ENABLED(CONFIG_FEC)248		/* Freescale Fast Ethernet Controller */249		{ "fsl,imx25-fec",   "phy-reset-gpios", "phy-reset-active-high" },250		{ "fsl,imx27-fec",   "phy-reset-gpios", "phy-reset-active-high" },251		{ "fsl,imx28-fec",   "phy-reset-gpios", "phy-reset-active-high" },252		{ "fsl,imx6q-fec",   "phy-reset-gpios", "phy-reset-active-high" },253		{ "fsl,mvf600-fec",  "phy-reset-gpios", "phy-reset-active-high" },254		{ "fsl,imx6sx-fec",  "phy-reset-gpios", "phy-reset-active-high" },255		{ "fsl,imx6ul-fec",  "phy-reset-gpios", "phy-reset-active-high" },256		{ "fsl,imx8mq-fec",  "phy-reset-gpios", "phy-reset-active-high" },257		{ "fsl,imx8qm-fec",  "phy-reset-gpios", "phy-reset-active-high" },258		{ "fsl,s32v234-fec", "phy-reset-gpios", "phy-reset-active-high" },259#endif260#if IS_ENABLED(CONFIG_PCI_IMX6)261		{ "fsl,imx6q-pcie",  "reset-gpio", "reset-gpio-active-high" },262		{ "fsl,imx6sx-pcie", "reset-gpio", "reset-gpio-active-high" },263		{ "fsl,imx6qp-pcie", "reset-gpio", "reset-gpio-active-high" },264		{ "fsl,imx7d-pcie",  "reset-gpio", "reset-gpio-active-high" },265		{ "fsl,imx8mq-pcie", "reset-gpio", "reset-gpio-active-high" },266		{ "fsl,imx8mm-pcie", "reset-gpio", "reset-gpio-active-high" },267		{ "fsl,imx8mp-pcie", "reset-gpio", "reset-gpio-active-high" },268#endif269 270		/*271		 * The regulator GPIO handles are specified such that the272		 * presence or absence of "enable-active-high" solely controls273		 * the polarity of the GPIO line. Any phandle flags must274		 * be actively ignored.275		 */276#if IS_ENABLED(CONFIG_REGULATOR_FIXED_VOLTAGE)277		{ "regulator-fixed",   "gpios",        "enable-active-high" },278		{ "regulator-fixed",   "gpio",         "enable-active-high" },279		{ "reg-fixed-voltage", "gpios",        "enable-active-high" },280		{ "reg-fixed-voltage", "gpio",         "enable-active-high" },281#endif282#if IS_ENABLED(CONFIG_REGULATOR_GPIO)283		{ "regulator-gpio",    "enable-gpio",  "enable-active-high" },284		{ "regulator-gpio",    "enable-gpios", "enable-active-high" },285#endif286#if IS_ENABLED(CONFIG_MMC_ATMELMCI)287		{ "atmel,hsmci",       "cd-gpios",     "cd-inverted" },288#endif289	};290	unsigned int i;291	bool active_high;292 293#if IS_ENABLED(CONFIG_MMC_ATMELMCI)294	/*295	 * The Atmel HSMCI has compatible property in the parent node and296	 * gpio property in a child node297	 */298	if (of_device_is_compatible(np->parent, "atmel,hsmci")) {299		np_compat = np->parent;300		np_propname = np;301	}302#endif303 304	for (i = 0; i < ARRAY_SIZE(gpios); i++) {305		if (of_device_is_compatible(np_compat, gpios[i].compatible) &&306		    !strcmp(propname, gpios[i].gpio_propname)) {307			active_high = of_property_read_bool(np_propname,308						gpios[i].polarity_propname);309			of_gpio_quirk_polarity(np, active_high, flags);310			break;311		}312	}313}314 315static void of_gpio_flags_quirks(const struct device_node *np,316				 const char *propname,317				 enum of_gpio_flags *flags,318				 int index)319{320	of_gpio_try_fixup_polarity(np, propname, flags);321	of_gpio_set_polarity_by_property(np, propname, flags);322 323	/*324	 * Legacy open drain handling for fixed voltage regulators.325	 */326	if (IS_ENABLED(CONFIG_REGULATOR) &&327	    of_device_is_compatible(np, "reg-fixed-voltage") &&328	    of_property_read_bool(np, "gpio-open-drain")) {329		*flags |= (OF_GPIO_SINGLE_ENDED | OF_GPIO_OPEN_DRAIN);330		pr_info("%s uses legacy open drain flag - update the DTS if you can\n",331			of_node_full_name(np));332	}333 334	/*335	 * Legacy handling of SPI active high chip select. If we have a336	 * property named "cs-gpios" we need to inspect the child node337	 * to determine if the flags should have inverted semantics.338	 */339	if (IS_ENABLED(CONFIG_SPI_MASTER) && !strcmp(propname, "cs-gpios") &&340	    of_property_read_bool(np, "cs-gpios")) {341		u32 cs;342		int ret;343 344		for_each_child_of_node_scoped(np, child) {345			ret = of_property_read_u32(child, "reg", &cs);346			if (ret)347				continue;348			if (cs == index) {349				/*350				 * SPI children have active low chip selects351				 * by default. This can be specified negatively352				 * by just omitting "spi-cs-high" in the353				 * device node, or actively by tagging on354				 * GPIO_ACTIVE_LOW as flag in the device355				 * tree. If the line is simultaneously356				 * tagged as active low in the device tree357				 * and has the "spi-cs-high" set, we get a358				 * conflict and the "spi-cs-high" flag will359				 * take precedence.360				 */361				bool active_high = of_property_read_bool(child,362								"spi-cs-high");363				of_gpio_quirk_polarity(child, active_high,364						       flags);365				break;366			}367		}368	}369 370	/* Legacy handling of stmmac's active-low PHY reset line */371	if (IS_ENABLED(CONFIG_STMMAC_ETH) &&372	    !strcmp(propname, "snps,reset-gpio") &&373	    of_property_read_bool(np, "snps,reset-active-low"))374		*flags |= OF_GPIO_ACTIVE_LOW;375}376 377/**378 * of_get_named_gpiod_flags() - Get a GPIO descriptor and flags for GPIO API379 * @np:		device node to get GPIO from380 * @propname:	property name containing gpio specifier(s)381 * @index:	index of the GPIO382 * @flags:	a flags pointer to fill in383 *384 * Returns:385 * GPIO descriptor to use with Linux GPIO API, or one of the errno386 * value on the error condition. If @flags is not NULL the function also fills387 * in flags for the GPIO.388 */389static struct gpio_desc *of_get_named_gpiod_flags(const struct device_node *np,390		     const char *propname, int index, enum of_gpio_flags *flags)391{392	struct of_phandle_args gpiospec;393	struct gpio_desc *desc;394	int ret;395 396	ret = of_parse_phandle_with_args_map(np, propname, "gpio", index,397					     &gpiospec);398	if (ret) {399		pr_debug("%s: can't parse '%s' property of node '%pOF[%d]'\n",400			__func__, propname, np, index);401		return ERR_PTR(ret);402	}403 404	struct gpio_device *gdev __free(gpio_device_put) =405				of_find_gpio_device_by_xlate(&gpiospec);406	if (!gdev) {407		desc = ERR_PTR(-EPROBE_DEFER);408		goto out;409	}410 411	desc = of_xlate_and_get_gpiod_flags(gpio_device_get_chip(gdev),412					    &gpiospec, flags);413	if (IS_ERR(desc))414		goto out;415 416	if (flags)417		of_gpio_flags_quirks(np, propname, flags, index);418 419	pr_debug("%s: parsed '%s' property of node '%pOF[%d]' - status (%d)\n",420		 __func__, propname, np, index,421		 PTR_ERR_OR_ZERO(desc));422 423out:424	of_node_put(gpiospec.np);425 426	return desc;427}428 429/**430 * of_get_named_gpio() - Get a GPIO number to use with GPIO API431 * @np:		device node to get GPIO from432 * @propname:	Name of property containing gpio specifier(s)433 * @index:	index of the GPIO434 *435 * **DEPRECATED** This function is deprecated and must not be used in new code.436 *437 * Returns:438 * GPIO number to use with Linux generic GPIO API, or one of the errno439 * value on the error condition.440 */441int of_get_named_gpio(const struct device_node *np, const char *propname,442		      int index)443{444	struct gpio_desc *desc;445 446	desc = of_get_named_gpiod_flags(np, propname, index, NULL);447 448	if (IS_ERR(desc))449		return PTR_ERR(desc);450	else451		return desc_to_gpio(desc);452}453EXPORT_SYMBOL_GPL(of_get_named_gpio);454 455/* Converts gpio_lookup_flags into bitmask of GPIO_* values */456static unsigned long of_convert_gpio_flags(enum of_gpio_flags flags)457{458	unsigned long lflags = GPIO_LOOKUP_FLAGS_DEFAULT;459 460	if (flags & OF_GPIO_ACTIVE_LOW)461		lflags |= GPIO_ACTIVE_LOW;462 463	if (flags & OF_GPIO_SINGLE_ENDED) {464		if (flags & OF_GPIO_OPEN_DRAIN)465			lflags |= GPIO_OPEN_DRAIN;466		else467			lflags |= GPIO_OPEN_SOURCE;468	}469 470	if (flags & OF_GPIO_TRANSITORY)471		lflags |= GPIO_TRANSITORY;472 473	if (flags & OF_GPIO_PULL_UP)474		lflags |= GPIO_PULL_UP;475 476	if (flags & OF_GPIO_PULL_DOWN)477		lflags |= GPIO_PULL_DOWN;478 479	if (flags & OF_GPIO_PULL_DISABLE)480		lflags |= GPIO_PULL_DISABLE;481 482	return lflags;483}484 485static struct gpio_desc *of_find_gpio_rename(struct device_node *np,486					     const char *con_id,487					     unsigned int idx,488					     enum of_gpio_flags *of_flags)489{490	static const struct of_rename_gpio {491		const char *con_id;492		const char *legacy_id;	/* NULL - same as con_id */493		/*494		 * Compatible string can be set to NULL in case where495		 * matching to a particular compatible is not practical,496		 * but it should only be done for gpio names that have497		 * vendor prefix to reduce risk of false positives.498		 * Addition of such entries is strongly discouraged.499		 */500		const char *compatible;501	} gpios[] = {502#if IS_ENABLED(CONFIG_LCD_HX8357)503		/* Himax LCD controllers used "gpios-reset" */504		{ "reset",	"gpios-reset",	"himax,hx8357" },505		{ "reset",	"gpios-reset",	"himax,hx8369" },506#endif507#if IS_ENABLED(CONFIG_MFD_ARIZONA)508		{ "wlf,reset",	NULL,		NULL },509#endif510#if IS_ENABLED(CONFIG_RTC_DRV_MOXART)511		{ "rtc-data",	"gpio-rtc-data",	"moxa,moxart-rtc" },512		{ "rtc-sclk",	"gpio-rtc-sclk",	"moxa,moxart-rtc" },513		{ "rtc-reset",	"gpio-rtc-reset",	"moxa,moxart-rtc" },514#endif515#if IS_ENABLED(CONFIG_NFC_MRVL_I2C)516		{ "reset",	"reset-n-io",	"marvell,nfc-i2c" },517#endif518#if IS_ENABLED(CONFIG_NFC_MRVL_SPI)519		{ "reset",	"reset-n-io",	"marvell,nfc-spi" },520#endif521#if IS_ENABLED(CONFIG_NFC_MRVL_UART)522		{ "reset",	"reset-n-io",	"marvell,nfc-uart" },523		{ "reset",	"reset-n-io",	"mrvl,nfc-uart" },524#endif525#if IS_ENABLED(CONFIG_PCI_LANTIQ)526		/* MIPS Lantiq PCI */527		{ "reset",	"gpio-reset",	"lantiq,pci-xway" },528#endif529 530		/*531		 * Some regulator bindings happened before we managed to532		 * establish that GPIO properties should be named533		 * "foo-gpios" so we have this special kludge for them.534		 */535#if IS_ENABLED(CONFIG_REGULATOR_ARIZONA_LDO1)536		{ "wlf,ldoena",  NULL,		NULL }, /* Arizona */537#endif538#if IS_ENABLED(CONFIG_REGULATOR_WM8994)539		{ "wlf,ldo1ena", NULL,		NULL }, /* WM8994 */540		{ "wlf,ldo2ena", NULL,		NULL }, /* WM8994 */541#endif542 543#if IS_ENABLED(CONFIG_SND_SOC_CS42L56)544		{ "reset",	"cirrus,gpio-nreset",	"cirrus,cs42l56" },545#endif546#if IS_ENABLED(CONFIG_SND_SOC_MT2701_CS42448)547		{ "i2s1-in-sel-gpio1",	NULL,	"mediatek,mt2701-cs42448-machine" },548		{ "i2s1-in-sel-gpio2",	NULL,	"mediatek,mt2701-cs42448-machine" },549#endif550#if IS_ENABLED(CONFIG_SND_SOC_TLV320AIC3X)551		{ "reset",	"gpio-reset",	"ti,tlv320aic3x" },552		{ "reset",	"gpio-reset",	"ti,tlv320aic33" },553		{ "reset",	"gpio-reset",	"ti,tlv320aic3007" },554		{ "reset",	"gpio-reset",	"ti,tlv320aic3104" },555		{ "reset",	"gpio-reset",	"ti,tlv320aic3106" },556#endif557#if IS_ENABLED(CONFIG_SPI_GPIO)558		/*559		 * The SPI GPIO bindings happened before we managed to560		 * establish that GPIO properties should be named561		 * "foo-gpios" so we have this special kludge for them.562		 */563		{ "miso",	"gpio-miso",	"spi-gpio" },564		{ "mosi",	"gpio-mosi",	"spi-gpio" },565		{ "sck",	"gpio-sck",	"spi-gpio" },566#endif567 568		/*569		 * The old Freescale bindings use simply "gpios" as name570		 * for the chip select lines rather than "cs-gpios" like571		 * all other SPI hardware. Allow this specifically for572		 * Freescale and PPC devices.573		 */574#if IS_ENABLED(CONFIG_SPI_FSL_SPI)575		{ "cs",		"gpios",	"fsl,spi" },576		{ "cs",		"gpios",	"aeroflexgaisler,spictrl" },577#endif578#if IS_ENABLED(CONFIG_SPI_PPC4xx)579		{ "cs",		"gpios",	"ibm,ppc4xx-spi" },580#endif581 582#if IS_ENABLED(CONFIG_TYPEC_FUSB302)583		/*584		 * Fairchild FUSB302 host is using undocumented "fcs,int_n"585		 * property without the compulsory "-gpios" suffix.586		 */587		{ "fcs,int_n",	NULL,		"fcs,fusb302" },588#endif589	};590	struct gpio_desc *desc;591	const char *legacy_id;592	unsigned int i;593 594	if (!con_id)595		return ERR_PTR(-ENOENT);596 597	for (i = 0; i < ARRAY_SIZE(gpios); i++) {598		if (strcmp(con_id, gpios[i].con_id))599			continue;600 601		if (gpios[i].compatible &&602		    !of_device_is_compatible(np, gpios[i].compatible))603			continue;604 605		legacy_id = gpios[i].legacy_id ?: gpios[i].con_id;606		desc = of_get_named_gpiod_flags(np, legacy_id, idx, of_flags);607		if (!gpiod_not_found(desc)) {608			pr_info("%s uses legacy gpio name '%s' instead of '%s-gpios'\n",609				of_node_full_name(np), legacy_id, con_id);610			return desc;611		}612	}613 614	return ERR_PTR(-ENOENT);615}616 617static struct gpio_desc *of_find_mt2701_gpio(struct device_node *np,618					     const char *con_id,619					     unsigned int idx,620					     enum of_gpio_flags *of_flags)621{622	struct gpio_desc *desc;623	const char *legacy_id;624 625	if (!IS_ENABLED(CONFIG_SND_SOC_MT2701_CS42448))626		return ERR_PTR(-ENOENT);627 628	if (!of_device_is_compatible(np, "mediatek,mt2701-cs42448-machine"))629		return ERR_PTR(-ENOENT);630 631	if (!con_id || strcmp(con_id, "i2s1-in-sel"))632		return ERR_PTR(-ENOENT);633 634	if (idx == 0)635		legacy_id = "i2s1-in-sel-gpio1";636	else if (idx == 1)637		legacy_id = "i2s1-in-sel-gpio2";638	else639		return ERR_PTR(-ENOENT);640 641	desc = of_get_named_gpiod_flags(np, legacy_id, 0, of_flags);642	if (!gpiod_not_found(desc))643		pr_info("%s is using legacy gpio name '%s' instead of '%s-gpios'\n",644			of_node_full_name(np), legacy_id, con_id);645 646	return desc;647}648 649/*650 * Trigger sources are special, they allow us to use any GPIO as a LED trigger651 * and have the name "trigger-sources" no matter which kind of phandle it is652 * pointing to, whether to a GPIO, a USB host, a network PHY etc. So in this case653 * we allow looking something up that is not named "foo-gpios".654 */655static struct gpio_desc *of_find_trigger_gpio(struct device_node *np,656					      const char *con_id,657					      unsigned int idx,658					      enum of_gpio_flags *of_flags)659{660	struct gpio_desc *desc;661 662	if (!IS_ENABLED(CONFIG_LEDS_TRIGGER_GPIO))663		return ERR_PTR(-ENOENT);664 665	if (!con_id || strcmp(con_id, "trigger-sources"))666		return ERR_PTR(-ENOENT);667 668	desc = of_get_named_gpiod_flags(np, con_id, idx, of_flags);669	if (!gpiod_not_found(desc))670		pr_debug("%s is used as a trigger\n", of_node_full_name(np));671 672	return desc;673}674 675 676typedef struct gpio_desc *(*of_find_gpio_quirk)(struct device_node *np,677						const char *con_id,678						unsigned int idx,679						enum of_gpio_flags *of_flags);680static const of_find_gpio_quirk of_find_gpio_quirks[] = {681	of_find_gpio_rename,682	of_find_mt2701_gpio,683	of_find_trigger_gpio,684	NULL685};686 687struct gpio_desc *of_find_gpio(struct device_node *np, const char *con_id,688			       unsigned int idx, unsigned long *flags)689{690	char propname[32]; /* 32 is max size of property name */691	enum of_gpio_flags of_flags;692	const of_find_gpio_quirk *q;693	struct gpio_desc *desc;694 695	/* Try GPIO property "foo-gpios" and "foo-gpio" */696	for_each_gpio_property_name(propname, con_id) {697		desc = of_get_named_gpiod_flags(np, propname, idx, &of_flags);698		if (!gpiod_not_found(desc))699			break;700	}701 702	/* Properly named GPIO was not found, try workarounds */703	for (q = of_find_gpio_quirks; gpiod_not_found(desc) && *q; q++)704		desc = (*q)(np, con_id, idx, &of_flags);705 706	if (IS_ERR(desc))707		return desc;708 709	*flags = of_convert_gpio_flags(of_flags);710 711	return desc;712}713 714/**715 * of_parse_own_gpio() - Get a GPIO hog descriptor, names and flags for GPIO API716 * @np:		device node to get GPIO from717 * @chip:	GPIO chip whose hog is parsed718 * @idx:	Index of the GPIO to parse719 * @name:	GPIO line name720 * @lflags:	bitmask of gpio_lookup_flags GPIO_* values - returned from721 *		of_find_gpio() or of_parse_own_gpio()722 * @dflags:	gpiod_flags - optional GPIO initialization flags723 *724 * Returns:725 * GPIO descriptor to use with Linux GPIO API, or one of the errno726 * value on the error condition.727 */728static struct gpio_desc *of_parse_own_gpio(struct device_node *np,729					   struct gpio_chip *chip,730					   unsigned int idx, const char **name,731					   unsigned long *lflags,732					   enum gpiod_flags *dflags)733{734	struct device_node *chip_np;735	enum of_gpio_flags xlate_flags;736	struct of_phandle_args gpiospec;737	struct gpio_desc *desc;738	unsigned int i;739	u32 tmp;740	int ret;741 742	chip_np = dev_of_node(&chip->gpiodev->dev);743	if (!chip_np)744		return ERR_PTR(-EINVAL);745 746	xlate_flags = 0;747	*lflags = GPIO_LOOKUP_FLAGS_DEFAULT;748	*dflags = GPIOD_ASIS;749 750	ret = of_property_read_u32(chip_np, "#gpio-cells", &tmp);751	if (ret)752		return ERR_PTR(ret);753 754	gpiospec.np = chip_np;755	gpiospec.args_count = tmp;756 757	for (i = 0; i < tmp; i++) {758		ret = of_property_read_u32_index(np, "gpios", idx * tmp + i,759						 &gpiospec.args[i]);760		if (ret)761			return ERR_PTR(ret);762	}763 764	desc = of_xlate_and_get_gpiod_flags(chip, &gpiospec, &xlate_flags);765	if (IS_ERR(desc))766		return desc;767 768	*lflags = of_convert_gpio_flags(xlate_flags);769 770	if (of_property_read_bool(np, "input"))771		*dflags |= GPIOD_IN;772	else if (of_property_read_bool(np, "output-low"))773		*dflags |= GPIOD_OUT_LOW;774	else if (of_property_read_bool(np, "output-high"))775		*dflags |= GPIOD_OUT_HIGH;776	else {777		pr_warn("GPIO line %d (%pOFn): no hogging state specified, bailing out\n",778			desc_to_gpio(desc), np);779		return ERR_PTR(-EINVAL);780	}781 782	if (name && of_property_read_string(np, "line-name", name))783		*name = np->name;784 785	return desc;786}787 788/**789 * of_gpiochip_add_hog - Add all hogs in a hog device node790 * @chip:	gpio chip to act on791 * @hog:	device node describing the hogs792 *793 * Returns:794 * 0 on success, or negative errno on failure.795 */796static int of_gpiochip_add_hog(struct gpio_chip *chip, struct device_node *hog)797{798	enum gpiod_flags dflags;799	struct gpio_desc *desc;800	unsigned long lflags;801	const char *name;802	unsigned int i;803	int ret;804 805	for (i = 0;; i++) {806		desc = of_parse_own_gpio(hog, chip, i, &name, &lflags, &dflags);807		if (IS_ERR(desc))808			break;809 810		ret = gpiod_hog(desc, name, lflags, dflags);811		if (ret < 0)812			return ret;813 814#ifdef CONFIG_OF_DYNAMIC815		WRITE_ONCE(desc->hog, hog);816#endif817	}818 819	return 0;820}821 822/**823 * of_gpiochip_scan_gpios - Scan gpio-controller for gpio definitions824 * @chip:	gpio chip to act on825 *826 * This is only used by of_gpiochip_add to request/set GPIO initial827 * configuration.828 *829 * Returns:830 * 0 on success, or negative errno on failure.831 */832static int of_gpiochip_scan_gpios(struct gpio_chip *chip)833{834	int ret;835 836	for_each_available_child_of_node_scoped(dev_of_node(&chip->gpiodev->dev), np) {837		if (!of_property_read_bool(np, "gpio-hog"))838			continue;839 840		ret = of_gpiochip_add_hog(chip, np);841		if (ret < 0)842			return ret;843 844		of_node_set_flag(np, OF_POPULATED);845	}846 847	return 0;848}849 850#ifdef CONFIG_OF_DYNAMIC851/**852 * of_gpiochip_remove_hog - Remove all hogs in a hog device node853 * @chip:	gpio chip to act on854 * @hog:	device node describing the hogs855 */856static void of_gpiochip_remove_hog(struct gpio_chip *chip,857				   struct device_node *hog)858{859	struct gpio_desc *desc;860 861	for_each_gpio_desc_with_flag(chip, desc, FLAG_IS_HOGGED)862		if (READ_ONCE(desc->hog) == hog)863			gpiochip_free_own_desc(desc);864}865 866static int of_gpiochip_match_node(struct gpio_chip *chip, const void *data)867{868	return device_match_of_node(&chip->gpiodev->dev, data);869}870 871static struct gpio_device *of_find_gpio_device_by_node(struct device_node *np)872{873	return gpio_device_find(np, of_gpiochip_match_node);874}875 876static int of_gpio_notify(struct notifier_block *nb, unsigned long action,877			  void *arg)878{879	struct gpio_device *gdev __free(gpio_device_put) = NULL;880	struct of_reconfig_data *rd = arg;881	int ret;882 883	/*884	 * This only supports adding and removing complete gpio-hog nodes.885	 * Modifying an existing gpio-hog node is not supported (except for886	 * changing its "status" property, which is treated the same as887	 * addition/removal).888	 */889	switch (of_reconfig_get_state_change(action, arg)) {890	case OF_RECONFIG_CHANGE_ADD:891		if (!of_property_read_bool(rd->dn, "gpio-hog"))892			return NOTIFY_DONE;	/* not for us */893 894		if (of_node_test_and_set_flag(rd->dn, OF_POPULATED))895			return NOTIFY_DONE;896 897		gdev = of_find_gpio_device_by_node(rd->dn->parent);898		if (!gdev)899			return NOTIFY_DONE;	/* not for us */900 901		ret = of_gpiochip_add_hog(gpio_device_get_chip(gdev), rd->dn);902		if (ret < 0) {903			pr_err("%s: failed to add hogs for %pOF\n", __func__,904			       rd->dn);905			of_node_clear_flag(rd->dn, OF_POPULATED);906			return notifier_from_errno(ret);907		}908		return NOTIFY_OK;909 910	case OF_RECONFIG_CHANGE_REMOVE:911		if (!of_node_check_flag(rd->dn, OF_POPULATED))912			return NOTIFY_DONE;	/* already depopulated */913 914		gdev = of_find_gpio_device_by_node(rd->dn->parent);915		if (!gdev)916			return NOTIFY_DONE;	/* not for us */917 918		of_gpiochip_remove_hog(gpio_device_get_chip(gdev), rd->dn);919		of_node_clear_flag(rd->dn, OF_POPULATED);920		return NOTIFY_OK;921	}922 923	return NOTIFY_DONE;924}925 926struct notifier_block gpio_of_notifier = {927	.notifier_call = of_gpio_notify,928};929#endif /* CONFIG_OF_DYNAMIC */930 931/**932 * of_gpio_simple_xlate - translate gpiospec to the GPIO number and flags933 * @gc:		pointer to the gpio_chip structure934 * @gpiospec:	GPIO specifier as found in the device tree935 * @flags:	a flags pointer to fill in936 *937 * This is simple translation function, suitable for the most 1:1 mapped938 * GPIO chips. This function performs only one sanity check: whether GPIO939 * is less than ngpios (that is specified in the gpio_chip).940 *941 * Returns:942 * GPIO number (>= 0) on success, negative errno on failure.943 */944static int of_gpio_simple_xlate(struct gpio_chip *gc,945				const struct of_phandle_args *gpiospec,946				u32 *flags)947{948	/*949	 * We're discouraging gpio_cells < 2, since that way you'll have to950	 * write your own xlate function (that will have to retrieve the GPIO951	 * number and the flags from a single gpio cell -- this is possible,952	 * but not recommended).953	 */954	if (gc->of_gpio_n_cells < 2) {955		WARN_ON(1);956		return -EINVAL;957	}958 959	if (WARN_ON(gpiospec->args_count < gc->of_gpio_n_cells))960		return -EINVAL;961 962	if (gpiospec->args[0] >= gc->ngpio)963		return -EINVAL;964 965	if (flags)966		*flags = gpiospec->args[1];967 968	return gpiospec->args[0];969}970 971#if IS_ENABLED(CONFIG_OF_GPIO_MM_GPIOCHIP)972#include <linux/gpio/legacy-of-mm-gpiochip.h>973/**974 * of_mm_gpiochip_add_data - Add memory mapped GPIO chip (bank)975 * @np:		device node of the GPIO chip976 * @mm_gc:	pointer to the of_mm_gpio_chip allocated structure977 * @data:	driver data to store in the struct gpio_chip978 *979 * To use this function you should allocate and fill mm_gc with:980 *981 * 1) In the gpio_chip structure:982 *    - all the callbacks983 *    - of_gpio_n_cells984 *    - of_xlate callback (optional)985 *986 * 3) In the of_mm_gpio_chip structure:987 *    - save_regs callback (optional)988 *989 * If succeeded, this function will map bank's memory and will990 * do all necessary work for you. Then you'll able to use .regs991 * to manage GPIOs from the callbacks.992 *993 * Returns:994 * 0 on success, or negative errno on failure.995 */996int of_mm_gpiochip_add_data(struct device_node *np,997			    struct of_mm_gpio_chip *mm_gc,998			    void *data)999{1000	int ret = -ENOMEM;1001	struct gpio_chip *gc = &mm_gc->gc;1002 1003	gc->label = kasprintf(GFP_KERNEL, "%pOF", np);1004	if (!gc->label)1005		goto err0;1006 1007	mm_gc->regs = of_iomap(np, 0);1008	if (!mm_gc->regs)1009		goto err1;1010 1011	gc->base = -1;1012 1013	if (mm_gc->save_regs)1014		mm_gc->save_regs(mm_gc);1015 1016	fwnode_handle_put(mm_gc->gc.fwnode);1017	mm_gc->gc.fwnode = fwnode_handle_get(of_fwnode_handle(np));1018 1019	ret = gpiochip_add_data(gc, data);1020	if (ret)1021		goto err2;1022 1023	return 0;1024err2:1025	of_node_put(np);1026	iounmap(mm_gc->regs);1027err1:1028	kfree(gc->label);1029err0:1030	pr_err("%pOF: GPIO chip registration failed with status %d\n", np, ret);1031	return ret;1032}1033EXPORT_SYMBOL_GPL(of_mm_gpiochip_add_data);1034 1035/**1036 * of_mm_gpiochip_remove - Remove memory mapped GPIO chip (bank)1037 * @mm_gc:	pointer to the of_mm_gpio_chip allocated structure1038 */1039void of_mm_gpiochip_remove(struct of_mm_gpio_chip *mm_gc)1040{1041	struct gpio_chip *gc = &mm_gc->gc;1042 1043	gpiochip_remove(gc);1044	iounmap(mm_gc->regs);1045	kfree(gc->label);1046}1047EXPORT_SYMBOL_GPL(of_mm_gpiochip_remove);1048#endif1049 1050#ifdef CONFIG_PINCTRL1051static int of_gpiochip_add_pin_range(struct gpio_chip *chip)1052{1053	struct of_phandle_args pinspec;1054	struct pinctrl_dev *pctldev;1055	struct device_node *np;1056	int index = 0, ret, trim;1057	const char *name;1058	static const char group_names_propname[] = "gpio-ranges-group-names";1059	bool has_group_names;1060 1061	np = dev_of_node(&chip->gpiodev->dev);1062	if (!np)1063		return 0;1064 1065	has_group_names = of_property_present(np, group_names_propname);1066 1067	for (;; index++) {1068		ret = of_parse_phandle_with_fixed_args(np, "gpio-ranges", 3,1069				index, &pinspec);1070		if (ret)1071			break;1072 1073		pctldev = of_pinctrl_get(pinspec.np);1074		of_node_put(pinspec.np);1075		if (!pctldev)1076			return -EPROBE_DEFER;1077 1078		/* Ignore ranges outside of this GPIO chip */1079		if (pinspec.args[0] >= (chip->offset + chip->ngpio))1080			continue;1081		if (pinspec.args[0] + pinspec.args[2] <= chip->offset)1082			continue;1083 1084		if (pinspec.args[2]) {1085			/* npins != 0: linear range */1086			if (has_group_names) {1087				of_property_read_string_index(np,1088						group_names_propname,1089						index, &name);1090				if (strlen(name)) {1091					pr_err("%pOF: Group name of numeric GPIO ranges must be the empty string.\n",1092						np);1093					break;1094				}1095			}1096 1097			/* Trim the range to fit this GPIO chip */1098			if (chip->offset > pinspec.args[0]) {1099				trim = chip->offset - pinspec.args[0];1100				pinspec.args[2] -= trim;1101				pinspec.args[1] += trim;1102				pinspec.args[0] = 0;1103			} else {1104				pinspec.args[0] -= chip->offset;1105			}1106			if ((pinspec.args[0] + pinspec.args[2]) > chip->ngpio)1107				pinspec.args[2] = chip->ngpio - pinspec.args[0];1108 1109			ret = gpiochip_add_pin_range(chip,1110					pinctrl_dev_get_devname(pctldev),1111					pinspec.args[0],1112					pinspec.args[1],1113					pinspec.args[2]);1114			if (ret)1115				return ret;1116		} else {1117			/* npins == 0: special range */1118			if (pinspec.args[1]) {1119				pr_err("%pOF: Illegal gpio-range format.\n",1120					np);1121				break;1122			}1123 1124			if (!has_group_names) {1125				pr_err("%pOF: GPIO group range requested but no %s property.\n",1126					np, group_names_propname);1127				break;1128			}1129 1130			ret = of_property_read_string_index(np,1131						group_names_propname,1132						index, &name);1133			if (ret)1134				break;1135 1136			if (!strlen(name)) {1137				pr_err("%pOF: Group name of GPIO group range cannot be the empty string.\n",1138				np);1139				break;1140			}1141 1142			ret = gpiochip_add_pingroup_range(chip, pctldev,1143						pinspec.args[0], name);1144			if (ret)1145				return ret;1146		}1147	}1148 1149	return 0;1150}1151 1152#else1153static int of_gpiochip_add_pin_range(struct gpio_chip *chip) { return 0; }1154#endif1155 1156int of_gpiochip_add(struct gpio_chip *chip)1157{1158	struct device_node *np;1159	int ret;1160 1161	np = dev_of_node(&chip->gpiodev->dev);1162	if (!np)1163		return 0;1164 1165	if (!chip->of_xlate) {1166		chip->of_gpio_n_cells = 2;1167		chip->of_xlate = of_gpio_simple_xlate;1168	}1169 1170	if (chip->of_gpio_n_cells > MAX_PHANDLE_ARGS)1171		return -EINVAL;1172 1173	ret = of_gpiochip_add_pin_range(chip);1174	if (ret)1175		return ret;1176 1177	of_node_get(np);1178 1179	ret = of_gpiochip_scan_gpios(chip);1180	if (ret)1181		of_node_put(np);1182 1183	return ret;1184}1185 1186void of_gpiochip_remove(struct gpio_chip *chip)1187{1188	of_node_put(dev_of_node(&chip->gpiodev->dev));1189}1190