// SPDX-License-Identifier: GPL-2.0+ /* * OF helpers for the GPIO API * * Copyright (c) 2007-2008 MontaVista Software, Inc. * * Author: Anton Vorontsov */ #include #include #include #include #include #include #include #include #include #include #include #include #include #include "gpiolib.h" #include "gpiolib-of.h" /* * This is Linux-specific flags. By default controllers' and Linux' mapping * match, but GPIO controllers are free to translate their own flags to * Linux-specific in their .xlate callback. Though, 1:1 mapping is recommended. */ enum of_gpio_flags { OF_GPIO_ACTIVE_LOW = 0x1, OF_GPIO_SINGLE_ENDED = 0x2, OF_GPIO_OPEN_DRAIN = 0x4, OF_GPIO_TRANSITORY = 0x8, OF_GPIO_PULL_UP = 0x10, OF_GPIO_PULL_DOWN = 0x20, OF_GPIO_PULL_DISABLE = 0x40, }; /** * of_gpio_named_count() - Count GPIOs for a device * @np: device node to count GPIOs for * @propname: property name containing gpio specifier(s) * * The function returns the count of GPIOs specified for a node. * Note that the empty GPIO specifiers count too. Returns either * Number of gpios defined in property, * -EINVAL for an incorrectly formed gpios property, or * -ENOENT for a missing gpios property * * Example: * gpios = <0 * &gpio1 1 2 * 0 * &gpio2 3 4>; * * The above example defines four GPIOs, two of which are not specified. * This function will return '4' */ static int of_gpio_named_count(const struct device_node *np, const char *propname) { return of_count_phandle_with_args(np, propname, "#gpio-cells"); } /** * of_gpio_spi_cs_get_count() - special GPIO counting for SPI * @dev: Consuming device * @con_id: Function within the GPIO consumer * * Some elder GPIO controllers need special quirks. Currently we handle * the Freescale and PPC GPIO controller with bindings that doesn't use the * established "cs-gpios" for chip selects but instead rely on * "gpios" for the chip select lines. If we detect this, we redirect * the counting of "cs-gpios" to count "gpios" transparent to the * driver. */ static int of_gpio_spi_cs_get_count(struct device *dev, const char *con_id) { struct device_node *np = dev->of_node; if (!IS_ENABLED(CONFIG_SPI_MASTER)) return 0; if (!con_id || strcmp(con_id, "cs")) return 0; if (!of_device_is_compatible(np, "fsl,spi") && !of_device_is_compatible(np, "aeroflexgaisler,spictrl") && !of_device_is_compatible(np, "ibm,ppc4xx-spi")) return 0; return of_gpio_named_count(np, "gpios"); } int of_gpio_get_count(struct device *dev, const char *con_id) { int ret; char propname[32]; unsigned int i; ret = of_gpio_spi_cs_get_count(dev, con_id); if (ret > 0) return ret; for (i = 0; i < ARRAY_SIZE(gpio_suffixes); i++) { if (con_id) snprintf(propname, sizeof(propname), "%s-%s", con_id, gpio_suffixes[i]); else snprintf(propname, sizeof(propname), "%s", gpio_suffixes[i]); ret = of_gpio_named_count(dev->of_node, propname); if (ret > 0) break; } return ret ? ret : -ENOENT; } static int of_gpiochip_match_node_and_xlate(struct gpio_chip *chip, const void *data) { const struct of_phandle_args *gpiospec = data; return device_match_of_node(&chip->gpiodev->dev, gpiospec->np) && chip->of_xlate && chip->of_xlate(chip, gpiospec, NULL) >= 0; } static struct gpio_device * of_find_gpio_device_by_xlate(struct of_phandle_args *gpiospec) { return gpio_device_find(gpiospec, of_gpiochip_match_node_and_xlate); } static struct gpio_desc *of_xlate_and_get_gpiod_flags(struct gpio_chip *chip, struct of_phandle_args *gpiospec, enum of_gpio_flags *flags) { int ret; if (chip->of_gpio_n_cells != gpiospec->args_count) return ERR_PTR(-EINVAL); ret = chip->of_xlate(chip, gpiospec, flags); if (ret < 0) return ERR_PTR(ret); return gpiochip_get_desc(chip, ret); } /* * Overrides stated polarity of a gpio line and warns when there is a * discrepancy. */ static void of_gpio_quirk_polarity(const struct device_node *np, bool active_high, enum of_gpio_flags *flags) { if (active_high) { if (*flags & OF_GPIO_ACTIVE_LOW) { pr_warn("%s GPIO handle specifies active low - ignored\n", of_node_full_name(np)); *flags &= ~OF_GPIO_ACTIVE_LOW; } } else { if (!(*flags & OF_GPIO_ACTIVE_LOW)) pr_info("%s enforce active low on GPIO handle\n", of_node_full_name(np)); *flags |= OF_GPIO_ACTIVE_LOW; } } /* * This quirk does static polarity overrides in cases where existing * DTS specified incorrect polarity. */ static void of_gpio_try_fixup_polarity(const struct device_node *np, const char *propname, enum of_gpio_flags *flags) { static const struct { const char *compatible; const char *propname; bool active_high; } gpios[] = { #if IS_ENABLED(CONFIG_LCD_HX8357) /* * Himax LCD controllers used incorrectly named * "gpios-reset" property and also specified wrong * polarity. */ { "himax,hx8357", "gpios-reset", false }, { "himax,hx8369", "gpios-reset", false }, /* * The rb-gpios semantics was undocumented and qi,lb60 (along with * the ingenic driver) got it wrong. The active state encodes the * NAND ready state, which is high level. Since there's no signal * inverter on this board, it should be active-high. Let's fix that * here for older DTs so we can re-use the generic nand_gpio_waitrdy() * helper, and be consistent with what other drivers do. */ { "qi,lb60", "rb-gpios", true }, #endif }; unsigned int i; for (i = 0; i < ARRAY_SIZE(gpios); i++) { if (of_device_is_compatible(np, gpios[i].compatible) && !strcmp(propname, gpios[i].propname)) { of_gpio_quirk_polarity(np, gpios[i].active_high, flags); break; } } } static void of_gpio_set_polarity_by_property(const struct device_node *np, const char *propname, enum of_gpio_flags *flags) { const struct device_node *np_compat = np; const struct device_node *np_propname = np; static const struct { const char *compatible; const char *gpio_propname; const char *polarity_propname; } gpios[] = { #if IS_ENABLED(CONFIG_FEC) /* Freescale Fast Ethernet Controller */ { "fsl,imx25-fec", "phy-reset-gpios", "phy-reset-active-high" }, { "fsl,imx27-fec", "phy-reset-gpios", "phy-reset-active-high" }, { "fsl,imx28-fec", "phy-reset-gpios", "phy-reset-active-high" }, { "fsl,imx6q-fec", "phy-reset-gpios", "phy-reset-active-high" }, { "fsl,mvf600-fec", "phy-reset-gpios", "phy-reset-active-high" }, { "fsl,imx6sx-fec", "phy-reset-gpios", "phy-reset-active-high" }, { "fsl,imx6ul-fec", "phy-reset-gpios", "phy-reset-active-high" }, { "fsl,imx8mq-fec", "phy-reset-gpios", "phy-reset-active-high" }, { "fsl,imx8qm-fec", "phy-reset-gpios", "phy-reset-active-high" }, { "fsl,s32v234-fec", "phy-reset-gpios", "phy-reset-active-high" }, #endif #if IS_ENABLED(CONFIG_PCI_IMX6) { "fsl,imx6q-pcie", "reset-gpio", "reset-gpio-active-high" }, { "fsl,imx6sx-pcie", "reset-gpio", "reset-gpio-active-high" }, { "fsl,imx6qp-pcie", "reset-gpio", "reset-gpio-active-high" }, { "fsl,imx7d-pcie", "reset-gpio", "reset-gpio-active-high" }, { "fsl,imx8mq-pcie", "reset-gpio", "reset-gpio-active-high" }, { "fsl,imx8mm-pcie", "reset-gpio", "reset-gpio-active-high" }, { "fsl,imx8mp-pcie", "reset-gpio", "reset-gpio-active-high" }, #endif /* * The regulator GPIO handles are specified such that the * presence or absence of "enable-active-high" solely controls * the polarity of the GPIO line. Any phandle flags must * be actively ignored. */ #if IS_ENABLED(CONFIG_REGULATOR_FIXED_VOLTAGE) { "regulator-fixed", "gpios", "enable-active-high" }, { "regulator-fixed", "gpio", "enable-active-high" }, { "reg-fixed-voltage", "gpios", "enable-active-high" }, { "reg-fixed-voltage", "gpio", "enable-active-high" }, #endif #if IS_ENABLED(CONFIG_REGULATOR_GPIO) { "regulator-gpio", "enable-gpio", "enable-active-high" }, { "regulator-gpio", "enable-gpios", "enable-active-high" }, #endif #if IS_ENABLED(CONFIG_MMC_ATMELMCI) { "atmel,hsmci", "cd-gpios", "cd-inverted" }, #endif }; unsigned int i; bool active_high; #if IS_ENABLED(CONFIG_MMC_ATMELMCI) /* * The Atmel HSMCI has compatible property in the parent node and * gpio property in a child node */ if (of_device_is_compatible(np->parent, "atmel,hsmci")) { np_compat = np->parent; np_propname = np; } #endif for (i = 0; i < ARRAY_SIZE(gpios); i++) { if (of_device_is_compatible(np_compat, gpios[i].compatible) && !strcmp(propname, gpios[i].gpio_propname)) { active_high = of_property_read_bool(np_propname, gpios[i].polarity_propname); of_gpio_quirk_polarity(np, active_high, flags); break; } } } static void of_gpio_flags_quirks(const struct device_node *np, const char *propname, enum of_gpio_flags *flags, int index) { of_gpio_try_fixup_polarity(np, propname, flags); of_gpio_set_polarity_by_property(np, propname, flags); /* * Legacy open drain handling for fixed voltage regulators. */ if (IS_ENABLED(CONFIG_REGULATOR) && of_device_is_compatible(np, "reg-fixed-voltage") && of_property_read_bool(np, "gpio-open-drain")) { *flags |= (OF_GPIO_SINGLE_ENDED | OF_GPIO_OPEN_DRAIN); pr_info("%s uses legacy open drain flag - update the DTS if you can\n", of_node_full_name(np)); } /* * Legacy handling of SPI active high chip select. If we have a * property named "cs-gpios" we need to inspect the child node * to determine if the flags should have inverted semantics. */ if (IS_ENABLED(CONFIG_SPI_MASTER) && !strcmp(propname, "cs-gpios") && of_property_read_bool(np, "cs-gpios")) { struct device_node *child; u32 cs; int ret; for_each_child_of_node(np, child) { ret = of_property_read_u32(child, "reg", &cs); if (ret) continue; if (cs == index) { /* * SPI children have active low chip selects * by default. This can be specified negatively * by just omitting "spi-cs-high" in the * device node, or actively by tagging on * GPIO_ACTIVE_LOW as flag in the device * tree. If the line is simultaneously * tagged as active low in the device tree * and has the "spi-cs-high" set, we get a * conflict and the "spi-cs-high" flag will * take precedence. */ bool active_high = of_property_read_bool(child, "spi-cs-high"); of_gpio_quirk_polarity(child, active_high, flags); of_node_put(child); break; } } } /* Legacy handling of stmmac's active-low PHY reset line */ if (IS_ENABLED(CONFIG_STMMAC_ETH) && !strcmp(propname, "snps,reset-gpio") && of_property_read_bool(np, "snps,reset-active-low")) *flags |= OF_GPIO_ACTIVE_LOW; } /** * of_get_named_gpiod_flags() - Get a GPIO descriptor and flags for GPIO API * @np: device node to get GPIO from * @propname: property name containing gpio specifier(s) * @index: index of the GPIO * @flags: a flags pointer to fill in * * Returns GPIO descriptor to use with Linux GPIO API, or one of the errno * value on the error condition. If @flags is not NULL the function also fills * in flags for the GPIO. */ static struct gpio_desc *of_get_named_gpiod_flags(const struct device_node *np, const char *propname, int index, enum of_gpio_flags *flags) { struct of_phandle_args gpiospec; struct gpio_desc *desc; int ret; ret = of_parse_phandle_with_args_map(np, propname, "gpio", index, &gpiospec); if (ret) { pr_debug("%s: can't parse '%s' property of node '%pOF[%d]'\n", __func__, propname, np, index); return ERR_PTR(ret); } struct gpio_device *gdev __free(gpio_device_put) = of_find_gpio_device_by_xlate(&gpiospec); if (!gdev) { desc = ERR_PTR(-EPROBE_DEFER); goto out; } desc = of_xlate_and_get_gpiod_flags(gpio_device_get_chip(gdev), &gpiospec, flags); if (IS_ERR(desc)) goto out; if (flags) of_gpio_flags_quirks(np, propname, flags, index); pr_debug("%s: parsed '%s' property of node '%pOF[%d]' - status (%d)\n", __func__, propname, np, index, PTR_ERR_OR_ZERO(desc)); out: of_node_put(gpiospec.np); return desc; } /** * of_get_named_gpio() - Get a GPIO number to use with GPIO API * @np: device node to get GPIO from * @propname: Name of property containing gpio specifier(s) * @index: index of the GPIO * * **DEPRECATED** This function is deprecated and must not be used in new code. * * Returns GPIO number to use with Linux generic GPIO API, or one of the errno * value on the error condition. */ int of_get_named_gpio(const struct device_node *np, const char *propname, int index) { struct gpio_desc *desc; desc = of_get_named_gpiod_flags(np, propname, index, NULL); if (IS_ERR(desc)) return PTR_ERR(desc); else return desc_to_gpio(desc); } EXPORT_SYMBOL_GPL(of_get_named_gpio); /* Converts gpio_lookup_flags into bitmask of GPIO_* values */ static unsigned long of_convert_gpio_flags(enum of_gpio_flags flags) { unsigned long lflags = GPIO_LOOKUP_FLAGS_DEFAULT; if (flags & OF_GPIO_ACTIVE_LOW) lflags |= GPIO_ACTIVE_LOW; if (flags & OF_GPIO_SINGLE_ENDED) { if (flags & OF_GPIO_OPEN_DRAIN) lflags |= GPIO_OPEN_DRAIN; else lflags |= GPIO_OPEN_SOURCE; } if (flags & OF_GPIO_TRANSITORY) lflags |= GPIO_TRANSITORY; if (flags & OF_GPIO_PULL_UP) lflags |= GPIO_PULL_UP; if (flags & OF_GPIO_PULL_DOWN) lflags |= GPIO_PULL_DOWN; if (flags & OF_GPIO_PULL_DISABLE) lflags |= GPIO_PULL_DISABLE; return lflags; } static struct gpio_desc *of_find_gpio_rename(struct device_node *np, const char *con_id, unsigned int idx, enum of_gpio_flags *of_flags) { static const struct of_rename_gpio { const char *con_id; const char *legacy_id; /* NULL - same as con_id */ /* * Compatible string can be set to NULL in case where * matching to a particular compatible is not practical, * but it should only be done for gpio names that have * vendor prefix to reduce risk of false positives. * Addition of such entries is strongly discouraged. */ const char *compatible; } gpios[] = { #if IS_ENABLED(CONFIG_LCD_HX8357) /* Himax LCD controllers used "gpios-reset" */ { "reset", "gpios-reset", "himax,hx8357" }, { "reset", "gpios-reset", "himax,hx8369" }, #endif #if IS_ENABLED(CONFIG_MFD_ARIZONA) { "wlf,reset", NULL, NULL }, #endif #if IS_ENABLED(CONFIG_RTC_DRV_MOXART) { "rtc-data", "gpio-rtc-data", "moxa,moxart-rtc" }, { "rtc-sclk", "gpio-rtc-sclk", "moxa,moxart-rtc" }, { "rtc-reset", "gpio-rtc-reset", "moxa,moxart-rtc" }, #endif #if IS_ENABLED(CONFIG_NFC_MRVL_I2C) { "reset", "reset-n-io", "marvell,nfc-i2c" }, #endif #if IS_ENABLED(CONFIG_NFC_MRVL_SPI) { "reset", "reset-n-io", "marvell,nfc-spi" }, #endif #if IS_ENABLED(CONFIG_NFC_MRVL_UART) { "reset", "reset-n-io", "marvell,nfc-uart" }, { "reset", "reset-n-io", "mrvl,nfc-uart" }, #endif #if !IS_ENABLED(CONFIG_PCI_LANTIQ) /* MIPS Lantiq PCI */ { "reset", "gpios-reset", "lantiq,pci-xway" }, #endif /* * Some regulator bindings happened before we managed to * establish that GPIO properties should be named * "foo-gpios" so we have this special kludge for them. */ #if IS_ENABLED(CONFIG_REGULATOR_ARIZONA_LDO1) { "wlf,ldoena", NULL, NULL }, /* Arizona */ #endif #if IS_ENABLED(CONFIG_REGULATOR_WM8994) { "wlf,ldo1ena", NULL, NULL }, /* WM8994 */ { "wlf,ldo2ena", NULL, NULL }, /* WM8994 */ #endif #if IS_ENABLED(CONFIG_SND_SOC_CS42L56) { "reset", "cirrus,gpio-nreset", "cirrus,cs42l56" }, #endif #if IS_ENABLED(CONFIG_SND_SOC_MT2701_CS42448) { "i2s1-in-sel-gpio1", NULL, "mediatek,mt2701-cs42448-machine" }, { "i2s1-in-sel-gpio2", NULL, "mediatek,mt2701-cs42448-machine" }, #endif #if IS_ENABLED(CONFIG_SND_SOC_TLV320AIC3X) { "reset", "gpio-reset", "ti,tlv320aic3x" }, { "reset", "gpio-reset", "ti,tlv320aic33" }, { "reset", "gpio-reset", "ti,tlv320aic3007" }, { "reset", "gpio-reset", "ti,tlv320aic3104" }, { "reset", "gpio-reset", "ti,tlv320aic3106" }, #endif #if IS_ENABLED(CONFIG_SPI_GPIO) /* * The SPI GPIO bindings happened before we managed to * establish that GPIO properties should be named * "foo-gpios" so we have this special kludge for them. */ { "miso", "gpio-miso", "spi-gpio" }, { "mosi", "gpio-mosi", "spi-gpio" }, { "sck", "gpio-sck", "spi-gpio" }, #endif /* * The old Freescale bindings use simply "gpios" as name * for the chip select lines rather than "cs-gpios" like * all other SPI hardware. Allow this specifically for * Freescale and PPC devices. */ #if IS_ENABLED(CONFIG_SPI_FSL_SPI) { "cs", "gpios", "fsl,spi" }, { "cs", "gpios", "aeroflexgaisler,spictrl" }, #endif #if IS_ENABLED(CONFIG_SPI_PPC4xx) { "cs", "gpios", "ibm,ppc4xx-spi" }, #endif #if IS_ENABLED(CONFIG_TYPEC_FUSB302) /* * Fairchild FUSB302 host is using undocumented "fcs,int_n" * property without the compulsory "-gpios" suffix. */ { "fcs,int_n", NULL, "fcs,fusb302" }, #endif }; struct gpio_desc *desc; const char *legacy_id; unsigned int i; if (!con_id) return ERR_PTR(-ENOENT); for (i = 0; i < ARRAY_SIZE(gpios); i++) { if (strcmp(con_id, gpios[i].con_id)) continue; if (gpios[i].compatible && !of_device_is_compatible(np, gpios[i].compatible)) continue; legacy_id = gpios[i].legacy_id ?: gpios[i].con_id; desc = of_get_named_gpiod_flags(np, legacy_id, idx, of_flags); if (!gpiod_not_found(desc)) { pr_info("%s uses legacy gpio name '%s' instead of '%s-gpios'\n", of_node_full_name(np), legacy_id, con_id); return desc; } } return ERR_PTR(-ENOENT); } static struct gpio_desc *of_find_mt2701_gpio(struct device_node *np, const char *con_id, unsigned int idx, enum of_gpio_flags *of_flags) { struct gpio_desc *desc; const char *legacy_id; if (!IS_ENABLED(CONFIG_SND_SOC_MT2701_CS42448)) return ERR_PTR(-ENOENT); if (!of_device_is_compatible(np, "mediatek,mt2701-cs42448-machine")) return ERR_PTR(-ENOENT); if (!con_id || strcmp(con_id, "i2s1-in-sel")) return ERR_PTR(-ENOENT); if (idx == 0) legacy_id = "i2s1-in-sel-gpio1"; else if (idx == 1) legacy_id = "i2s1-in-sel-gpio2"; else return ERR_PTR(-ENOENT); desc = of_get_named_gpiod_flags(np, legacy_id, 0, of_flags); if (!gpiod_not_found(desc)) pr_info("%s is using legacy gpio name '%s' instead of '%s-gpios'\n", of_node_full_name(np), legacy_id, con_id); return desc; } /* * Trigger sources are special, they allow us to use any GPIO as a LED trigger * and have the name "trigger-sources" no matter which kind of phandle it is * pointing to, whether to a GPIO, a USB host, a network PHY etc. So in this case * we allow looking something up that is not named "foo-gpios". */ static struct gpio_desc *of_find_trigger_gpio(struct device_node *np, const char *con_id, unsigned int idx, enum of_gpio_flags *of_flags) { struct gpio_desc *desc; if (!IS_ENABLED(CONFIG_LEDS_TRIGGER_GPIO)) return ERR_PTR(-ENOENT); if (!con_id || strcmp(con_id, "trigger-sources")) return ERR_PTR(-ENOENT); desc = of_get_named_gpiod_flags(np, con_id, idx, of_flags); if (!gpiod_not_found(desc)) pr_debug("%s is used as a trigger\n", of_node_full_name(np)); return desc; } typedef struct gpio_desc *(*of_find_gpio_quirk)(struct device_node *np, const char *con_id, unsigned int idx, enum of_gpio_flags *of_flags); static const of_find_gpio_quirk of_find_gpio_quirks[] = { of_find_gpio_rename, of_find_mt2701_gpio, of_find_trigger_gpio, NULL }; struct gpio_desc *of_find_gpio(struct device_node *np, const char *con_id, unsigned int idx, unsigned long *flags) { char prop_name[32]; /* 32 is max size of property name */ enum of_gpio_flags of_flags; const of_find_gpio_quirk *q; struct gpio_desc *desc; unsigned int i; /* Try GPIO property "foo-gpios" and "foo-gpio" */ for (i = 0; i < ARRAY_SIZE(gpio_suffixes); i++) { if (con_id) snprintf(prop_name, sizeof(prop_name), "%s-%s", con_id, gpio_suffixes[i]); else snprintf(prop_name, sizeof(prop_name), "%s", gpio_suffixes[i]); desc = of_get_named_gpiod_flags(np, prop_name, idx, &of_flags); if (!gpiod_not_found(desc)) break; } /* Properly named GPIO was not found, try workarounds */ for (q = of_find_gpio_quirks; gpiod_not_found(desc) && *q; q++) desc = (*q)(np, con_id, idx, &of_flags); if (IS_ERR(desc)) return desc; *flags = of_convert_gpio_flags(of_flags); return desc; } /** * of_parse_own_gpio() - Get a GPIO hog descriptor, names and flags for GPIO API * @np: device node to get GPIO from * @chip: GPIO chip whose hog is parsed * @idx: Index of the GPIO to parse * @name: GPIO line name * @lflags: bitmask of gpio_lookup_flags GPIO_* values - returned from * of_find_gpio() or of_parse_own_gpio() * @dflags: gpiod_flags - optional GPIO initialization flags * * Returns GPIO descriptor to use with Linux GPIO API, or one of the errno * value on the error condition. */ static struct gpio_desc *of_parse_own_gpio(struct device_node *np, struct gpio_chip *chip, unsigned int idx, const char **name, unsigned long *lflags, enum gpiod_flags *dflags) { struct device_node *chip_np; enum of_gpio_flags xlate_flags; struct of_phandle_args gpiospec; struct gpio_desc *desc; unsigned int i; u32 tmp; int ret; chip_np = dev_of_node(&chip->gpiodev->dev); if (!chip_np) return ERR_PTR(-EINVAL); xlate_flags = 0; *lflags = GPIO_LOOKUP_FLAGS_DEFAULT; *dflags = GPIOD_ASIS; ret = of_property_read_u32(chip_np, "#gpio-cells", &tmp); if (ret) return ERR_PTR(ret); gpiospec.np = chip_np; gpiospec.args_count = tmp; for (i = 0; i < tmp; i++) { ret = of_property_read_u32_index(np, "gpios", idx * tmp + i, &gpiospec.args[i]); if (ret) return ERR_PTR(ret); } desc = of_xlate_and_get_gpiod_flags(chip, &gpiospec, &xlate_flags); if (IS_ERR(desc)) return desc; *lflags = of_convert_gpio_flags(xlate_flags); if (of_property_read_bool(np, "input")) *dflags |= GPIOD_IN; else if (of_property_read_bool(np, "output-low")) *dflags |= GPIOD_OUT_LOW; else if (of_property_read_bool(np, "output-high")) *dflags |= GPIOD_OUT_HIGH; else { pr_warn("GPIO line %d (%pOFn): no hogging state specified, bailing out\n", desc_to_gpio(desc), np); return ERR_PTR(-EINVAL); } if (name && of_property_read_string(np, "line-name", name)) *name = np->name; return desc; } /** * of_gpiochip_add_hog - Add all hogs in a hog device node * @chip: gpio chip to act on * @hog: device node describing the hogs * * Returns error if it fails otherwise 0 on success. */ static int of_gpiochip_add_hog(struct gpio_chip *chip, struct device_node *hog) { enum gpiod_flags dflags; struct gpio_desc *desc; unsigned long lflags; const char *name; unsigned int i; int ret; for (i = 0;; i++) { desc = of_parse_own_gpio(hog, chip, i, &name, &lflags, &dflags); if (IS_ERR(desc)) break; ret = gpiod_hog(desc, name, lflags, dflags); if (ret < 0) return ret; #ifdef CONFIG_OF_DYNAMIC WRITE_ONCE(desc->hog, hog); #endif } return 0; } /** * of_gpiochip_scan_gpios - Scan gpio-controller for gpio definitions * @chip: gpio chip to act on * * This is only used by of_gpiochip_add to request/set GPIO initial * configuration. * It returns error if it fails otherwise 0 on success. */ static int of_gpiochip_scan_gpios(struct gpio_chip *chip) { struct device_node *np; int ret; for_each_available_child_of_node(dev_of_node(&chip->gpiodev->dev), np) { if (!of_property_read_bool(np, "gpio-hog")) continue; ret = of_gpiochip_add_hog(chip, np); if (ret < 0) { of_node_put(np); return ret; } of_node_set_flag(np, OF_POPULATED); } return 0; } #ifdef CONFIG_OF_DYNAMIC /** * of_gpiochip_remove_hog - Remove all hogs in a hog device node * @chip: gpio chip to act on * @hog: device node describing the hogs */ static void of_gpiochip_remove_hog(struct gpio_chip *chip, struct device_node *hog) { struct gpio_desc *desc; for_each_gpio_desc_with_flag(chip, desc, FLAG_IS_HOGGED) if (READ_ONCE(desc->hog) == hog) gpiochip_free_own_desc(desc); } static int of_gpiochip_match_node(struct gpio_chip *chip, const void *data) { return device_match_of_node(&chip->gpiodev->dev, data); } static struct gpio_device *of_find_gpio_device_by_node(struct device_node *np) { return gpio_device_find(np, of_gpiochip_match_node); } static int of_gpio_notify(struct notifier_block *nb, unsigned long action, void *arg) { struct gpio_device *gdev __free(gpio_device_put) = NULL; struct of_reconfig_data *rd = arg; int ret; /* * This only supports adding and removing complete gpio-hog nodes. * Modifying an existing gpio-hog node is not supported (except for * changing its "status" property, which is treated the same as * addition/removal). */ switch (of_reconfig_get_state_change(action, arg)) { case OF_RECONFIG_CHANGE_ADD: if (!of_property_read_bool(rd->dn, "gpio-hog")) return NOTIFY_DONE; /* not for us */ if (of_node_test_and_set_flag(rd->dn, OF_POPULATED)) return NOTIFY_DONE; gdev = of_find_gpio_device_by_node(rd->dn->parent); if (!gdev) return NOTIFY_DONE; /* not for us */ ret = of_gpiochip_add_hog(gpio_device_get_chip(gdev), rd->dn); if (ret < 0) { pr_err("%s: failed to add hogs for %pOF\n", __func__, rd->dn); of_node_clear_flag(rd->dn, OF_POPULATED); return notifier_from_errno(ret); } return NOTIFY_OK; case OF_RECONFIG_CHANGE_REMOVE: if (!of_node_check_flag(rd->dn, OF_POPULATED)) return NOTIFY_DONE; /* already depopulated */ gdev = of_find_gpio_device_by_node(rd->dn->parent); if (!gdev) return NOTIFY_DONE; /* not for us */ of_gpiochip_remove_hog(gpio_device_get_chip(gdev), rd->dn); of_node_clear_flag(rd->dn, OF_POPULATED); return NOTIFY_OK; } return NOTIFY_DONE; } struct notifier_block gpio_of_notifier = { .notifier_call = of_gpio_notify, }; #endif /* CONFIG_OF_DYNAMIC */ /** * of_gpio_simple_xlate - translate gpiospec to the GPIO number and flags * @gc: pointer to the gpio_chip structure * @gpiospec: GPIO specifier as found in the device tree * @flags: a flags pointer to fill in * * This is simple translation function, suitable for the most 1:1 mapped * GPIO chips. This function performs only one sanity check: whether GPIO * is less than ngpios (that is specified in the gpio_chip). */ static int of_gpio_simple_xlate(struct gpio_chip *gc, const struct of_phandle_args *gpiospec, u32 *flags) { /* * We're discouraging gpio_cells < 2, since that way you'll have to * write your own xlate function (that will have to retrieve the GPIO * number and the flags from a single gpio cell -- this is possible, * but not recommended). */ if (gc->of_gpio_n_cells < 2) { WARN_ON(1); return -EINVAL; } if (WARN_ON(gpiospec->args_count < gc->of_gpio_n_cells)) return -EINVAL; if (gpiospec->args[0] >= gc->ngpio) return -EINVAL; if (flags) *flags = gpiospec->args[1]; return gpiospec->args[0]; } #if IS_ENABLED(CONFIG_OF_GPIO_MM_GPIOCHIP) #include /** * of_mm_gpiochip_add_data - Add memory mapped GPIO chip (bank) * @np: device node of the GPIO chip * @mm_gc: pointer to the of_mm_gpio_chip allocated structure * @data: driver data to store in the struct gpio_chip * * To use this function you should allocate and fill mm_gc with: * * 1) In the gpio_chip structure: * - all the callbacks * - of_gpio_n_cells * - of_xlate callback (optional) * * 3) In the of_mm_gpio_chip structure: * - save_regs callback (optional) * * If succeeded, this function will map bank's memory and will * do all necessary work for you. Then you'll able to use .regs * to manage GPIOs from the callbacks. */ int of_mm_gpiochip_add_data(struct device_node *np, struct of_mm_gpio_chip *mm_gc, void *data) { int ret = -ENOMEM; struct gpio_chip *gc = &mm_gc->gc; gc->label = kasprintf(GFP_KERNEL, "%pOF", np); if (!gc->label) goto err0; mm_gc->regs = of_iomap(np, 0); if (!mm_gc->regs) goto err1; gc->base = -1; if (mm_gc->save_regs) mm_gc->save_regs(mm_gc); fwnode_handle_put(mm_gc->gc.fwnode); mm_gc->gc.fwnode = fwnode_handle_get(of_fwnode_handle(np)); ret = gpiochip_add_data(gc, data); if (ret) goto err2; return 0; err2: of_node_put(np); iounmap(mm_gc->regs); err1: kfree(gc->label); err0: pr_err("%pOF: GPIO chip registration failed with status %d\n", np, ret); return ret; } EXPORT_SYMBOL_GPL(of_mm_gpiochip_add_data); /** * of_mm_gpiochip_remove - Remove memory mapped GPIO chip (bank) * @mm_gc: pointer to the of_mm_gpio_chip allocated structure */ void of_mm_gpiochip_remove(struct of_mm_gpio_chip *mm_gc) { struct gpio_chip *gc = &mm_gc->gc; gpiochip_remove(gc); iounmap(mm_gc->regs); kfree(gc->label); } EXPORT_SYMBOL_GPL(of_mm_gpiochip_remove); #endif #ifdef CONFIG_PINCTRL static int of_gpiochip_add_pin_range(struct gpio_chip *chip) { struct of_phandle_args pinspec; struct pinctrl_dev *pctldev; struct device_node *np; int index = 0, ret; const char *name; static const char group_names_propname[] = "gpio-ranges-group-names"; struct property *group_names; np = dev_of_node(&chip->gpiodev->dev); if (!np) return 0; group_names = of_find_property(np, group_names_propname, NULL); for (;; index++) { ret = of_parse_phandle_with_fixed_args(np, "gpio-ranges", 3, index, &pinspec); if (ret) break; pctldev = of_pinctrl_get(pinspec.np); of_node_put(pinspec.np); if (!pctldev) return -EPROBE_DEFER; if (pinspec.args[2]) { if (group_names) { of_property_read_string_index(np, group_names_propname, index, &name); if (strlen(name)) { pr_err("%pOF: Group name of numeric GPIO ranges must be the empty string.\n", np); break; } } /* npins != 0: linear range */ ret = gpiochip_add_pin_range(chip, pinctrl_dev_get_devname(pctldev), pinspec.args[0], pinspec.args[1], pinspec.args[2]); if (ret) return ret; } else { /* npins == 0: special range */ if (pinspec.args[1]) { pr_err("%pOF: Illegal gpio-range format.\n", np); break; } if (!group_names) { pr_err("%pOF: GPIO group range requested but no %s property.\n", np, group_names_propname); break; } ret = of_property_read_string_index(np, group_names_propname, index, &name); if (ret) break; if (!strlen(name)) { pr_err("%pOF: Group name of GPIO group range cannot be the empty string.\n", np); break; } ret = gpiochip_add_pingroup_range(chip, pctldev, pinspec.args[0], name); if (ret) return ret; } } return 0; } #else static int of_gpiochip_add_pin_range(struct gpio_chip *chip) { return 0; } #endif int of_gpiochip_add(struct gpio_chip *chip) { struct device_node *np; int ret; np = dev_of_node(&chip->gpiodev->dev); if (!np) return 0; if (!chip->of_xlate) { chip->of_gpio_n_cells = 2; chip->of_xlate = of_gpio_simple_xlate; } if (chip->of_gpio_n_cells > MAX_PHANDLE_ARGS) return -EINVAL; ret = of_gpiochip_add_pin_range(chip); if (ret) return ret; of_node_get(np); ret = of_gpiochip_scan_gpios(chip); if (ret) of_node_put(np); return ret; } void of_gpiochip_remove(struct gpio_chip *chip) { of_node_put(dev_of_node(&chip->gpiodev->dev)); }