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![Bartosz Golaszewski](/assets/img/avatar_default.png)
If the driver sets the fwnode in struct gpio_chip, let it take precedence over the of_node. This only affects OF-based systems, ACPI needs to be converted separately. Signed-off-by: Bartosz Golaszewski <brgl@bgdev.pl> Reviewed-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com> Acked-by: Linus Walleij <linus.walleij@linaro.org>
1057 lines
27 KiB
C
1057 lines
27 KiB
C
// SPDX-License-Identifier: GPL-2.0+
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/*
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* OF helpers for the GPIO API
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*
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* Copyright (c) 2007-2008 MontaVista Software, Inc.
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*
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* Author: Anton Vorontsov <avorontsov@ru.mvista.com>
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*/
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#include <linux/device.h>
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#include <linux/err.h>
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#include <linux/errno.h>
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#include <linux/module.h>
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#include <linux/io.h>
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#include <linux/gpio/consumer.h>
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#include <linux/of.h>
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#include <linux/of_address.h>
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#include <linux/of_gpio.h>
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#include <linux/pinctrl/pinctrl.h>
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#include <linux/slab.h>
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#include <linux/gpio/machine.h>
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#include "gpiolib.h"
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#include "gpiolib-of.h"
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/**
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* of_gpio_spi_cs_get_count() - special GPIO counting for SPI
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* @dev: Consuming device
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* @con_id: Function within the GPIO consumer
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*
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* Some elder GPIO controllers need special quirks. Currently we handle
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* the Freescale and PPC GPIO controller with bindings that doesn't use the
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* established "cs-gpios" for chip selects but instead rely on
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* "gpios" for the chip select lines. If we detect this, we redirect
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* the counting of "cs-gpios" to count "gpios" transparent to the
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* driver.
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*/
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static int of_gpio_spi_cs_get_count(struct device *dev, const char *con_id)
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{
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struct device_node *np = dev->of_node;
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if (!IS_ENABLED(CONFIG_SPI_MASTER))
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return 0;
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if (!con_id || strcmp(con_id, "cs"))
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return 0;
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if (!of_device_is_compatible(np, "fsl,spi") &&
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!of_device_is_compatible(np, "aeroflexgaisler,spictrl") &&
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!of_device_is_compatible(np, "ibm,ppc4xx-spi"))
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return 0;
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return of_gpio_named_count(np, "gpios");
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}
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/*
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* This is used by external users of of_gpio_count() from <linux/of_gpio.h>
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*
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* FIXME: get rid of those external users by converting them to GPIO
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* descriptors and let them all use gpiod_count()
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*/
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int of_gpio_get_count(struct device *dev, const char *con_id)
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{
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int ret;
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char propname[32];
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unsigned int i;
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ret = of_gpio_spi_cs_get_count(dev, con_id);
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if (ret > 0)
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return ret;
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for (i = 0; i < ARRAY_SIZE(gpio_suffixes); i++) {
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if (con_id)
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snprintf(propname, sizeof(propname), "%s-%s",
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con_id, gpio_suffixes[i]);
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else
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snprintf(propname, sizeof(propname), "%s",
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gpio_suffixes[i]);
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ret = of_gpio_named_count(dev->of_node, propname);
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if (ret > 0)
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break;
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}
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return ret ? ret : -ENOENT;
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}
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static int of_gpiochip_match_node_and_xlate(struct gpio_chip *chip, void *data)
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{
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struct of_phandle_args *gpiospec = data;
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return chip->gpiodev->dev.of_node == gpiospec->np &&
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chip->of_xlate &&
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chip->of_xlate(chip, gpiospec, NULL) >= 0;
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}
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static struct gpio_chip *of_find_gpiochip_by_xlate(
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struct of_phandle_args *gpiospec)
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{
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return gpiochip_find(gpiospec, of_gpiochip_match_node_and_xlate);
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}
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static struct gpio_desc *of_xlate_and_get_gpiod_flags(struct gpio_chip *chip,
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struct of_phandle_args *gpiospec,
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enum of_gpio_flags *flags)
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{
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int ret;
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if (chip->of_gpio_n_cells != gpiospec->args_count)
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return ERR_PTR(-EINVAL);
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ret = chip->of_xlate(chip, gpiospec, flags);
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if (ret < 0)
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return ERR_PTR(ret);
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return gpiochip_get_desc(chip, ret);
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}
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/**
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* of_gpio_need_valid_mask() - figure out if the OF GPIO driver needs
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* to set the .valid_mask
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* @gc: the target gpio_chip
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*
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* Return: true if the valid mask needs to be set
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*/
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bool of_gpio_need_valid_mask(const struct gpio_chip *gc)
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{
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int size;
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const struct device_node *np = gc->of_node;
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size = of_property_count_u32_elems(np, "gpio-reserved-ranges");
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if (size > 0 && size % 2 == 0)
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return true;
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return false;
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}
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static void of_gpio_flags_quirks(const struct device_node *np,
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const char *propname,
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enum of_gpio_flags *flags,
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int index)
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{
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/*
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* Some GPIO fixed regulator quirks.
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* Note that active low is the default.
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*/
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if (IS_ENABLED(CONFIG_REGULATOR) &&
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(of_device_is_compatible(np, "regulator-fixed") ||
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of_device_is_compatible(np, "reg-fixed-voltage") ||
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(!(strcmp(propname, "enable-gpio") &&
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strcmp(propname, "enable-gpios")) &&
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of_device_is_compatible(np, "regulator-gpio")))) {
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bool active_low = !of_property_read_bool(np,
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"enable-active-high");
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/*
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* The regulator GPIO handles are specified such that the
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* presence or absence of "enable-active-high" solely controls
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* the polarity of the GPIO line. Any phandle flags must
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* be actively ignored.
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*/
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if ((*flags & OF_GPIO_ACTIVE_LOW) && !active_low) {
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pr_warn("%s GPIO handle specifies active low - ignored\n",
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of_node_full_name(np));
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*flags &= ~OF_GPIO_ACTIVE_LOW;
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}
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if (active_low)
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*flags |= OF_GPIO_ACTIVE_LOW;
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}
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/*
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* Legacy open drain handling for fixed voltage regulators.
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*/
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if (IS_ENABLED(CONFIG_REGULATOR) &&
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of_device_is_compatible(np, "reg-fixed-voltage") &&
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of_property_read_bool(np, "gpio-open-drain")) {
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*flags |= (OF_GPIO_SINGLE_ENDED | OF_GPIO_OPEN_DRAIN);
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pr_info("%s uses legacy open drain flag - update the DTS if you can\n",
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of_node_full_name(np));
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}
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/*
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* Legacy handling of SPI active high chip select. If we have a
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* property named "cs-gpios" we need to inspect the child node
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* to determine if the flags should have inverted semantics.
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*/
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if (IS_ENABLED(CONFIG_SPI_MASTER) && !strcmp(propname, "cs-gpios") &&
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of_property_read_bool(np, "cs-gpios")) {
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struct device_node *child;
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u32 cs;
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int ret;
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for_each_child_of_node(np, child) {
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ret = of_property_read_u32(child, "reg", &cs);
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if (ret)
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continue;
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if (cs == index) {
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/*
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* SPI children have active low chip selects
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* by default. This can be specified negatively
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* by just omitting "spi-cs-high" in the
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* device node, or actively by tagging on
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* GPIO_ACTIVE_LOW as flag in the device
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* tree. If the line is simultaneously
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* tagged as active low in the device tree
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* and has the "spi-cs-high" set, we get a
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* conflict and the "spi-cs-high" flag will
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* take precedence.
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*/
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if (of_property_read_bool(child, "spi-cs-high")) {
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if (*flags & OF_GPIO_ACTIVE_LOW) {
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pr_warn("%s GPIO handle specifies active low - ignored\n",
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of_node_full_name(child));
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*flags &= ~OF_GPIO_ACTIVE_LOW;
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}
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} else {
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if (!(*flags & OF_GPIO_ACTIVE_LOW))
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pr_info("%s enforce active low on chipselect handle\n",
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of_node_full_name(child));
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*flags |= OF_GPIO_ACTIVE_LOW;
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}
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of_node_put(child);
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break;
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}
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}
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}
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/* Legacy handling of stmmac's active-low PHY reset line */
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if (IS_ENABLED(CONFIG_STMMAC_ETH) &&
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!strcmp(propname, "snps,reset-gpio") &&
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of_property_read_bool(np, "snps,reset-active-low"))
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*flags |= OF_GPIO_ACTIVE_LOW;
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}
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/**
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* of_get_named_gpiod_flags() - Get a GPIO descriptor and flags for GPIO API
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* @np: device node to get GPIO from
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* @propname: property name containing gpio specifier(s)
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* @index: index of the GPIO
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* @flags: a flags pointer to fill in
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*
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* Returns GPIO descriptor to use with Linux GPIO API, or one of the errno
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* value on the error condition. If @flags is not NULL the function also fills
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* in flags for the GPIO.
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*/
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static struct gpio_desc *of_get_named_gpiod_flags(const struct device_node *np,
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const char *propname, int index, enum of_gpio_flags *flags)
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{
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struct of_phandle_args gpiospec;
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struct gpio_chip *chip;
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struct gpio_desc *desc;
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int ret;
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ret = of_parse_phandle_with_args_map(np, propname, "gpio", index,
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&gpiospec);
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if (ret) {
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pr_debug("%s: can't parse '%s' property of node '%pOF[%d]'\n",
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__func__, propname, np, index);
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return ERR_PTR(ret);
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}
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chip = of_find_gpiochip_by_xlate(&gpiospec);
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if (!chip) {
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desc = ERR_PTR(-EPROBE_DEFER);
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goto out;
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}
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desc = of_xlate_and_get_gpiod_flags(chip, &gpiospec, flags);
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if (IS_ERR(desc))
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goto out;
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if (flags)
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of_gpio_flags_quirks(np, propname, flags, index);
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pr_debug("%s: parsed '%s' property of node '%pOF[%d]' - status (%d)\n",
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__func__, propname, np, index,
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PTR_ERR_OR_ZERO(desc));
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out:
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of_node_put(gpiospec.np);
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return desc;
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}
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int of_get_named_gpio_flags(const struct device_node *np, const char *list_name,
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int index, enum of_gpio_flags *flags)
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{
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struct gpio_desc *desc;
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desc = of_get_named_gpiod_flags(np, list_name, index, flags);
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if (IS_ERR(desc))
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return PTR_ERR(desc);
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else
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return desc_to_gpio(desc);
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}
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EXPORT_SYMBOL_GPL(of_get_named_gpio_flags);
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/**
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* gpiod_get_from_of_node() - obtain a GPIO from an OF node
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* @node: handle of the OF node
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* @propname: name of the DT property representing the GPIO
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* @index: index of the GPIO to obtain for the consumer
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* @dflags: GPIO initialization flags
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* @label: label to attach to the requested GPIO
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*
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* Returns:
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* On successful request the GPIO pin is configured in accordance with
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* provided @dflags.
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*
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* In case of error an ERR_PTR() is returned.
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*/
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struct gpio_desc *gpiod_get_from_of_node(const struct device_node *node,
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const char *propname, int index,
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enum gpiod_flags dflags,
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const char *label)
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{
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unsigned long lflags = GPIO_LOOKUP_FLAGS_DEFAULT;
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struct gpio_desc *desc;
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enum of_gpio_flags flags;
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bool active_low = false;
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bool single_ended = false;
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bool open_drain = false;
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bool transitory = false;
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int ret;
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desc = of_get_named_gpiod_flags(node, propname,
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index, &flags);
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if (!desc || IS_ERR(desc)) {
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return desc;
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}
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active_low = flags & OF_GPIO_ACTIVE_LOW;
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single_ended = flags & OF_GPIO_SINGLE_ENDED;
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open_drain = flags & OF_GPIO_OPEN_DRAIN;
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transitory = flags & OF_GPIO_TRANSITORY;
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ret = gpiod_request(desc, label);
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if (ret == -EBUSY && (dflags & GPIOD_FLAGS_BIT_NONEXCLUSIVE))
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return desc;
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if (ret)
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return ERR_PTR(ret);
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if (active_low)
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lflags |= GPIO_ACTIVE_LOW;
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if (single_ended) {
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if (open_drain)
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lflags |= GPIO_OPEN_DRAIN;
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else
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lflags |= GPIO_OPEN_SOURCE;
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}
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if (transitory)
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lflags |= GPIO_TRANSITORY;
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if (flags & OF_GPIO_PULL_UP)
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lflags |= GPIO_PULL_UP;
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if (flags & OF_GPIO_PULL_DOWN)
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lflags |= GPIO_PULL_DOWN;
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ret = gpiod_configure_flags(desc, propname, lflags, dflags);
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if (ret < 0) {
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gpiod_put(desc);
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return ERR_PTR(ret);
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}
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return desc;
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}
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EXPORT_SYMBOL_GPL(gpiod_get_from_of_node);
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/*
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* The SPI GPIO bindings happened before we managed to establish that GPIO
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* properties should be named "foo-gpios" so we have this special kludge for
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* them.
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*/
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static struct gpio_desc *of_find_spi_gpio(struct device *dev, const char *con_id,
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enum of_gpio_flags *of_flags)
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{
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char prop_name[32]; /* 32 is max size of property name */
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const struct device_node *np = dev->of_node;
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struct gpio_desc *desc;
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/*
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* Hopefully the compiler stubs the rest of the function if this
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* is false.
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*/
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if (!IS_ENABLED(CONFIG_SPI_MASTER))
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return ERR_PTR(-ENOENT);
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/* Allow this specifically for "spi-gpio" devices */
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if (!of_device_is_compatible(np, "spi-gpio") || !con_id)
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return ERR_PTR(-ENOENT);
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/* Will be "gpio-sck", "gpio-mosi" or "gpio-miso" */
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snprintf(prop_name, sizeof(prop_name), "%s-%s", "gpio", con_id);
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desc = of_get_named_gpiod_flags(np, prop_name, 0, of_flags);
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return desc;
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}
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/*
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* The old Freescale bindings use simply "gpios" as name for the chip select
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* lines rather than "cs-gpios" like all other SPI hardware. Account for this
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* with a special quirk.
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*/
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static struct gpio_desc *of_find_spi_cs_gpio(struct device *dev,
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const char *con_id,
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unsigned int idx,
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unsigned long *flags)
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{
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const struct device_node *np = dev->of_node;
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if (!IS_ENABLED(CONFIG_SPI_MASTER))
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return ERR_PTR(-ENOENT);
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/* Allow this specifically for Freescale and PPC devices */
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if (!of_device_is_compatible(np, "fsl,spi") &&
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!of_device_is_compatible(np, "aeroflexgaisler,spictrl") &&
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!of_device_is_compatible(np, "ibm,ppc4xx-spi"))
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return ERR_PTR(-ENOENT);
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/* Allow only if asking for "cs-gpios" */
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if (!con_id || strcmp(con_id, "cs"))
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return ERR_PTR(-ENOENT);
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|
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/*
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* While all other SPI controllers use "cs-gpios" the Freescale
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* uses just "gpios" so translate to that when "cs-gpios" is
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* requested.
|
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*/
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return of_find_gpio(dev, NULL, idx, flags);
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}
|
|
|
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/*
|
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* Some regulator bindings happened before we managed to establish that GPIO
|
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* properties should be named "foo-gpios" so we have this special kludge for
|
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* them.
|
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*/
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static struct gpio_desc *of_find_regulator_gpio(struct device *dev, const char *con_id,
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enum of_gpio_flags *of_flags)
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{
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/* These are the connection IDs we accept as legacy GPIO phandles */
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const char *whitelist[] = {
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"wlf,ldoena", /* Arizona */
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"wlf,ldo1ena", /* WM8994 */
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"wlf,ldo2ena", /* WM8994 */
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};
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const struct device_node *np = dev->of_node;
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struct gpio_desc *desc;
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int i;
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|
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if (!IS_ENABLED(CONFIG_REGULATOR))
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return ERR_PTR(-ENOENT);
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|
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if (!con_id)
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return ERR_PTR(-ENOENT);
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|
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i = match_string(whitelist, ARRAY_SIZE(whitelist), con_id);
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if (i < 0)
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return ERR_PTR(-ENOENT);
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|
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desc = of_get_named_gpiod_flags(np, con_id, 0, of_flags);
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return desc;
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}
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|
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static struct gpio_desc *of_find_arizona_gpio(struct device *dev,
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const char *con_id,
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enum of_gpio_flags *of_flags)
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{
|
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if (!IS_ENABLED(CONFIG_MFD_ARIZONA))
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return ERR_PTR(-ENOENT);
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|
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if (!con_id || strcmp(con_id, "wlf,reset"))
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return ERR_PTR(-ENOENT);
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|
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return of_get_named_gpiod_flags(dev->of_node, con_id, 0, of_flags);
|
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}
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|
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static struct gpio_desc *of_find_usb_gpio(struct device *dev,
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const char *con_id,
|
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enum of_gpio_flags *of_flags)
|
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{
|
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/*
|
|
* Currently this USB quirk is only for the Fairchild FUSB302 host which is using
|
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* an undocumented DT GPIO line named "fcs,int_n" without the compulsory "-gpios"
|
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* 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 (!gpiod_not_found(desc))
|
|
break;
|
|
}
|
|
|
|
if (gpiod_not_found(desc)) {
|
|
/* Special handling for SPI GPIOs if used */
|
|
desc = of_find_spi_gpio(dev, con_id, &of_flags);
|
|
}
|
|
|
|
if (gpiod_not_found(desc)) {
|
|
/* 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 (gpiod_not_found(desc)) {
|
|
/* Special handling for regulator GPIOs if used */
|
|
desc = of_find_regulator_gpio(dev, con_id, &of_flags);
|
|
}
|
|
|
|
if (gpiod_not_found(desc))
|
|
desc = of_find_arizona_gpio(dev, con_id, &of_flags);
|
|
|
|
if (gpiod_not_found(desc))
|
|
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 = 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;
|
|
|
|
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)
|
|
{
|
|
/* Set default OF node to parent's one if present */
|
|
if (gc->parent)
|
|
gdev->dev.of_node = gc->parent->of_node;
|
|
|
|
if (gc->fwnode)
|
|
gc->of_node = to_of_node(gc->fwnode);
|
|
|
|
/* 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;
|
|
}
|