// 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
* Some elder GPIO controllers need special quirks. Currently we handle
* the Freescale 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"))
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