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- // SPDX-License-Identifier: GPL-2.0+
- /*
- * OF helpers for the GPIO API
- *
- * Copyright (c) 2007-2008 MontaVista Software, Inc.
- *
- * Author: Anton Vorontsov <avorontsov@ru.mvista.com>
- */
- #include <linux/device.h>
- #include <linux/err.h>
- #include <linux/errno.h>
- #include <linux/module.h>
- #include <linux/io.h>
- #include <linux/gpio/consumer.h>
- #include <linux/of.h>
- #include <linux/of_address.h>
- #include <linux/of_gpio.h>
- #include <linux/pinctrl/pinctrl.h>
- #include <linux/slab.h>
- #include <linux/gpio/machine.h>
- #include "gpiolib.h"
- #include "gpiolib-of.h"
- /**
- * 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");
- }
- /*
- * This is used by external users of of_gpio_count() from <linux/of_gpio.h>
- *
- * FIXME: get rid of those external users by converting them to GPIO
- * descriptors and let them all use gpiod_count()
- */
- 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, void *data)
- {
- struct of_phandle_args *gpiospec = data;
- return chip->gpiodev->dev.of_node == gpiospec->np &&
- chip->of_xlate &&
- chip->of_xlate(chip, gpiospec, NULL) >= 0;
- }
- static struct gpio_chip *of_find_gpiochip_by_xlate(
- struct of_phandle_args *gpiospec)
- {
- return gpiochip_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);
- }
- /**
- * of_gpio_need_valid_mask() - figure out if the OF GPIO driver needs
- * to set the .valid_mask
- * @gc: the target gpio_chip
- *
- * Return: true if the valid mask needs to be set
- */
- bool of_gpio_need_valid_mask(const struct gpio_chip *gc)
- {
- int size;
- struct device_node *np = gc->of_node;
- size = of_property_count_u32_elems(np, "gpio-reserved-ranges");
- if (size > 0 && size % 2 == 0)
- return true;
- return false;
- }
- static void of_gpio_flags_quirks(struct device_node *np,
- const char *propname,
- enum of_gpio_flags *flags,
- int index)
- {
- /*
- * Some GPIO fixed regulator quirks.
- * Note that active low is the default.
- */
- if (IS_ENABLED(CONFIG_REGULATOR) &&
- (of_device_is_compatible(np, "regulator-fixed") ||
- of_device_is_compatible(np, "reg-fixed-voltage") ||
- (!(strcmp(propname, "enable-gpio") &&
- strcmp(propname, "enable-gpios")) &&
- of_device_is_compatible(np, "regulator-gpio")))) {
- bool active_low = !of_property_read_bool(np,
- "enable-active-high");
- /*
- * 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 ((*flags & OF_GPIO_ACTIVE_LOW) && !active_low) {
- pr_warn("%s GPIO handle specifies active low - ignored\n",
- of_node_full_name(np));
- *flags &= ~OF_GPIO_ACTIVE_LOW;
- }
- if (active_low)
- *flags |= OF_GPIO_ACTIVE_LOW;
- }
- /*
- * 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.
- */
- if (of_property_read_bool(child, "spi-cs-high")) {
- if (*flags & OF_GPIO_ACTIVE_LOW) {
- pr_warn("%s GPIO handle specifies active low - ignored\n",
- of_node_full_name(child));
- *flags &= ~OF_GPIO_ACTIVE_LOW;
- }
- } else {
- if (!(*flags & OF_GPIO_ACTIVE_LOW))
- pr_info("%s enforce active low on chipselect handle\n",
- of_node_full_name(child));
- *flags |= OF_GPIO_ACTIVE_LOW;
- }
- 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(struct device_node *np,
- const char *propname, int index, enum of_gpio_flags *flags)
- {
- struct of_phandle_args gpiospec;
- struct gpio_chip *chip;
- 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);
- }
- chip = of_find_gpiochip_by_xlate(&gpiospec);
- if (!chip) {
- desc = ERR_PTR(-EPROBE_DEFER);
- goto out;
- }
- desc = of_xlate_and_get_gpiod_flags(chip, &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;
- }
- int of_get_named_gpio_flags(struct device_node *np, const char *list_name,
- int index, enum of_gpio_flags *flags)
- {
- struct gpio_desc *desc;
- desc = of_get_named_gpiod_flags(np, list_name, index, flags);
- if (IS_ERR(desc))
- return PTR_ERR(desc);
- else
- return desc_to_gpio(desc);
- }
- EXPORT_SYMBOL_GPL(of_get_named_gpio_flags);
- /**
- * gpiod_get_from_of_node() - obtain a GPIO from an OF node
- * @node: handle of the OF node
- * @propname: name of the DT property representing the GPIO
- * @index: index of the GPIO to obtain for the consumer
- * @dflags: GPIO initialization flags
- * @label: label to attach to the requested GPIO
- *
- * Returns:
- * On successful request the GPIO pin is configured in accordance with
- * provided @dflags.
- *
- * In case of error an ERR_PTR() is returned.
- */
- struct gpio_desc *gpiod_get_from_of_node(struct device_node *node,
- const char *propname, int index,
- enum gpiod_flags dflags,
- const char *label)
- {
- unsigned long lflags = GPIO_LOOKUP_FLAGS_DEFAULT;
- struct gpio_desc *desc;
- enum of_gpio_flags flags;
- bool active_low = false;
- bool single_ended = false;
- bool open_drain = false;
- bool transitory = false;
- int ret;
- desc = of_get_named_gpiod_flags(node, propname,
- index, &flags);
- if (!desc || IS_ERR(desc)) {
- return desc;
- }
- active_low = flags & OF_GPIO_ACTIVE_LOW;
- single_ended = flags & OF_GPIO_SINGLE_ENDED;
- open_drain = flags & OF_GPIO_OPEN_DRAIN;
- transitory = flags & OF_GPIO_TRANSITORY;
- ret = gpiod_request(desc, label);
- if (ret == -EBUSY && (dflags & GPIOD_FLAGS_BIT_NONEXCLUSIVE))
- return desc;
- if (ret)
- return ERR_PTR(ret);
- if (active_low)
- lflags |= GPIO_ACTIVE_LOW;
- if (single_ended) {
- if (open_drain)
- lflags |= GPIO_OPEN_DRAIN;
- else
- lflags |= GPIO_OPEN_SOURCE;
- }
- if (transitory)
- lflags |= GPIO_TRANSITORY;
- if (flags & OF_GPIO_PULL_UP)
- lflags |= GPIO_PULL_UP;
- if (flags & OF_GPIO_PULL_DOWN)
- lflags |= GPIO_PULL_DOWN;
- ret = gpiod_configure_flags(desc, propname, lflags, dflags);
- if (ret < 0) {
- gpiod_put(desc);
- return ERR_PTR(ret);
- }
- return desc;
- }
- EXPORT_SYMBOL_GPL(gpiod_get_from_of_node);
- /*
- * 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.
- */
- static struct gpio_desc *of_find_spi_gpio(struct device *dev, const char *con_id,
- enum of_gpio_flags *of_flags)
- {
- char prop_name[32]; /* 32 is max size of property name */
- struct device_node *np = dev->of_node;
- struct gpio_desc *desc;
- /*
- * Hopefully the compiler stubs the rest of the function if this
- * is false.
- */
- if (!IS_ENABLED(CONFIG_SPI_MASTER))
- return ERR_PTR(-ENOENT);
- /* Allow this specifically for "spi-gpio" devices */
- if (!of_device_is_compatible(np, "spi-gpio") || !con_id)
- return ERR_PTR(-ENOENT);
- /* Will be "gpio-sck", "gpio-mosi" or "gpio-miso" */
- snprintf(prop_name, sizeof(prop_name), "%s-%s", "gpio", con_id);
- desc = of_get_named_gpiod_flags(np, prop_name, 0, of_flags);
- return desc;
- }
- /*
- * The old Freescale bindings use simply "gpios" as name for the chip select
- * lines rather than "cs-gpios" like all other SPI hardware. Account for this
- * with a special quirk.
- */
- static struct gpio_desc *of_find_spi_cs_gpio(struct device *dev,
- const char *con_id,
- unsigned int idx,
- unsigned long *flags)
- {
- struct device_node *np = dev->of_node;
- if (!IS_ENABLED(CONFIG_SPI_MASTER))
- return ERR_PTR(-ENOENT);
- /* Allow this specifically for Freescale and PPC devices */
- if (!of_device_is_compatible(np, "fsl,spi") &&
- !of_device_is_compatible(np, "aeroflexgaisler,spictrl") &&
- !of_device_is_compatible(np, "ibm,ppc4xx-spi"))
- return ERR_PTR(-ENOENT);
- /* Allow only if asking for "cs-gpios" */
- if (!con_id || strcmp(con_id, "cs"))
- return ERR_PTR(-ENOENT);
- /*
- * While all other SPI controllers use "cs-gpios" the Freescale
- * uses just "gpios" so translate to that when "cs-gpios" is
- * requested.
- */
- return of_find_gpio(dev, NULL, idx, flags);
- }
- /*
- * 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.
- */
- static struct gpio_desc *of_find_regulator_gpio(struct device *dev, const char *con_id,
- enum of_gpio_flags *of_flags)
- {
- /* These are the connection IDs we accept as legacy GPIO phandles */
- const char *whitelist[] = {
- "wlf,ldoena", /* Arizona */
- "wlf,ldo1ena", /* WM8994 */
- "wlf,ldo2ena", /* WM8994 */
- };
- struct device_node *np = dev->of_node;
- struct gpio_desc *desc;
- int i;
- if (!IS_ENABLED(CONFIG_REGULATOR))
- return ERR_PTR(-ENOENT);
- if (!con_id)
- return ERR_PTR(-ENOENT);
- i = match_string(whitelist, ARRAY_SIZE(whitelist), con_id);
- if (i < 0)
- return ERR_PTR(-ENOENT);
- desc = of_get_named_gpiod_flags(np, con_id, 0, of_flags);
- return desc;
- }
- static struct gpio_desc *of_find_arizona_gpio(struct device *dev,
- const char *con_id,
- enum of_gpio_flags *of_flags)
- {
- if (!IS_ENABLED(CONFIG_MFD_ARIZONA))
- return ERR_PTR(-ENOENT);
- if (!con_id || strcmp(con_id, "wlf,reset"))
- return ERR_PTR(-ENOENT);
- return of_get_named_gpiod_flags(dev->of_node, con_id, 0, of_flags);
- }
- static struct gpio_desc *of_find_usb_gpio(struct device *dev,
- const char *con_id,
- enum of_gpio_flags *of_flags)
- {
- /*
- * Currently this USB quirk is only for the Fairchild FUSB302 host which is using
- * an undocumented DT GPIO line named "fcs,int_n" without the compulsory "-gpios"
- * suffix.
- */
- if (!IS_ENABLED(CONFIG_TYPEC_FUSB302))
- return ERR_PTR(-ENOENT);
- if (!con_id || strcmp(con_id, "fcs,int_n"))
- return ERR_PTR(-ENOENT);
- return of_get_named_gpiod_flags(dev->of_node, con_id, 0, of_flags);
- }
- struct gpio_desc *of_find_gpio(struct device *dev, 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;
- 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(dev->of_node, prop_name, idx,
- &of_flags);
- if (!IS_ERR(desc) || PTR_ERR(desc) != -ENOENT)
- break;
- }
- if (PTR_ERR(desc) == -ENOENT) {
- /* Special handling for SPI GPIOs if used */
- desc = of_find_spi_gpio(dev, con_id, &of_flags);
- }
- if (PTR_ERR(desc) == -ENOENT) {
- /* This quirk looks up flags and all */
- desc = of_find_spi_cs_gpio(dev, con_id, idx, flags);
- if (!IS_ERR(desc))
- return desc;
- }
- if (PTR_ERR(desc) == -ENOENT) {
- /* Special handling for regulator GPIOs if used */
- desc = of_find_regulator_gpio(dev, con_id, &of_flags);
- }
- if (PTR_ERR(desc) == -ENOENT)
- desc = of_find_arizona_gpio(dev, con_id, &of_flags);
- if (PTR_ERR(desc) == -ENOENT)
- desc = of_find_usb_gpio(dev, con_id, &of_flags);
- if (IS_ERR(desc))
- return desc;
- if (of_flags & OF_GPIO_ACTIVE_LOW)
- *flags |= GPIO_ACTIVE_LOW;
- if (of_flags & OF_GPIO_SINGLE_ENDED) {
- if (of_flags & OF_GPIO_OPEN_DRAIN)
- *flags |= GPIO_OPEN_DRAIN;
- else
- *flags |= GPIO_OPEN_SOURCE;
- }
- if (of_flags & OF_GPIO_TRANSITORY)
- *flags |= GPIO_TRANSITORY;
- if (of_flags & OF_GPIO_PULL_UP)
- *flags |= GPIO_PULL_UP;
- if (of_flags & OF_GPIO_PULL_DOWN)
- *flags |= GPIO_PULL_DOWN;
- 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 = chip->of_node;
- if (!chip_np)
- return ERR_PTR(-EINVAL);
- xlate_flags = 0;
- *lflags = GPIO_LOOKUP_FLAGS_DEFAULT;
- *dflags = 0;
- 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;
- if (xlate_flags & OF_GPIO_ACTIVE_LOW)
- *lflags |= GPIO_ACTIVE_LOW;
- if (xlate_flags & OF_GPIO_TRANSITORY)
- *lflags |= GPIO_TRANSITORY;
- if (xlate_flags & OF_GPIO_PULL_UP)
- *lflags |= GPIO_PULL_UP;
- if (xlate_flags & OF_GPIO_PULL_DOWN)
- *lflags |= GPIO_PULL_DOWN;
- 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
- 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(chip->of_node, 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 *descs = chip->gpiodev->descs;
- unsigned int i;
- for (i = 0; i < chip->ngpio; i++) {
- if (test_bit(FLAG_IS_HOGGED, &descs[i].flags) &&
- descs[i].hog == hog)
- gpiochip_free_own_desc(&descs[i]);
- }
- }
- static int of_gpiochip_match_node(struct gpio_chip *chip, void *data)
- {
- return chip->gpiodev->dev.of_node == data;
- }
- static struct gpio_chip *of_find_gpiochip_by_node(struct device_node *np)
- {
- return gpiochip_find(np, of_gpiochip_match_node);
- }
- static int of_gpio_notify(struct notifier_block *nb, unsigned long action,
- void *arg)
- {
- struct of_reconfig_data *rd = arg;
- struct gpio_chip *chip;
- 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_OK; /* not for us */
- if (of_node_test_and_set_flag(rd->dn, OF_POPULATED))
- return NOTIFY_OK;
- chip = of_find_gpiochip_by_node(rd->dn->parent);
- if (chip == NULL)
- return NOTIFY_OK; /* not for us */
- ret = of_gpiochip_add_hog(chip, 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);
- }
- break;
- case OF_RECONFIG_CHANGE_REMOVE:
- if (!of_node_check_flag(rd->dn, OF_POPULATED))
- return NOTIFY_OK; /* already depopulated */
- chip = of_find_gpiochip_by_node(rd->dn->parent);
- if (chip == NULL)
- return NOTIFY_OK; /* not for us */
- of_gpiochip_remove_hog(chip, rd->dn);
- of_node_clear_flag(rd->dn, OF_POPULATED);
- break;
- }
- return NOTIFY_OK;
- }
- 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];
- }
- /**
- * 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);
- mm_gc->gc.of_node = np;
- ret = gpiochip_add_data(gc, data);
- if (ret)
- goto err2;
- return 0;
- err2:
- 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;
- if (!mm_gc)
- return;
- gpiochip_remove(gc);
- iounmap(mm_gc->regs);
- kfree(gc->label);
- }
- EXPORT_SYMBOL_GPL(of_mm_gpiochip_remove);
- static void of_gpiochip_init_valid_mask(struct gpio_chip *chip)
- {
- int len, i;
- u32 start, count;
- struct device_node *np = chip->of_node;
- len = of_property_count_u32_elems(np, "gpio-reserved-ranges");
- if (len < 0 || len % 2 != 0)
- return;
- for (i = 0; i < len; i += 2) {
- of_property_read_u32_index(np, "gpio-reserved-ranges",
- i, &start);
- of_property_read_u32_index(np, "gpio-reserved-ranges",
- i + 1, &count);
- if (start >= chip->ngpio || start + count >= chip->ngpio)
- continue;
- bitmap_clear(chip->valid_mask, start, count);
- }
- };
- #ifdef CONFIG_PINCTRL
- static int of_gpiochip_add_pin_range(struct gpio_chip *chip)
- {
- struct device_node *np = chip->of_node;
- struct of_phandle_args pinspec;
- struct pinctrl_dev *pctldev;
- int index = 0, ret;
- const char *name;
- static const char group_names_propname[] = "gpio-ranges-group-names";
- struct property *group_names;
- 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)
- {
- int ret;
- if (!chip->of_node)
- 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;
- of_gpiochip_init_valid_mask(chip);
- ret = of_gpiochip_add_pin_range(chip);
- if (ret)
- return ret;
- of_node_get(chip->of_node);
- ret = of_gpiochip_scan_gpios(chip);
- if (ret)
- of_node_put(chip->of_node);
- return ret;
- }
- void of_gpiochip_remove(struct gpio_chip *chip)
- {
- of_node_put(chip->of_node);
- }
- void of_gpio_dev_init(struct gpio_chip *gc, struct gpio_device *gdev)
- {
- /* If the gpiochip has an assigned OF node this takes precedence */
- if (gc->of_node)
- gdev->dev.of_node = gc->of_node;
- else
- gc->of_node = gdev->dev.of_node;
- if (gdev->dev.of_node)
- gdev->dev.fwnode = of_fwnode_handle(gdev->dev.of_node);
- }
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