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linux/drivers/gpio/gpiolib-of.c
Doug Berger e818cd3c8a gpio: of: support gpio-ranges for multiple gpiochip devices 
Some drivers (e.g. gpio-mt7621 and gpio-brcmstb) have multiple
gpiochip banks within a single device. Unfortunately, the
gpio-ranges property of the device node was being applied to
every gpiochip of the device with device relative GPIO offset
values rather than gpiochip relative GPIO offset values.

This commit makes use of the gpio_chip offset value which can be
non-zero for such devices to split the device node gpio-ranges
property into GPIO offset ranges that can be applied to each
of the relevant gpiochips of the device.

Signed-off-by: Doug Berger <opendmb@gmail.com>
Acked-by: Florian Fainelli <florian.fainelli@broadcom.com>
Link: https://lore.kernel.org/r/20240424185039.1707812-3-opendmb@gmail.com
Signed-off-by: Bartosz Golaszewski <bartosz.golaszewski@linaro.org>
2024-04-26 09:32:54 +02:00

1174 lines
32 KiB
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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/io.h>
#include <linux/module.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/string.h>
#include <linux/gpio/consumer.h>
#include <linux/gpio/machine.h>
#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
* @np: Consuming device node
* @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(const struct device_node *np,
const char *con_id)
{
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_count(const struct fwnode_handle *fwnode, const char *con_id)
{
const struct device_node *np = to_of_node(fwnode);
int ret;
char propname[32];
unsigned int i;
ret = of_gpio_spi_cs_get_count(np, 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(np, 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(const 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 <linux/gpio/legacy-of-mm-gpiochip.h>
/**
* 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, trim;
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;
/* Ignore ranges outside of this GPIO chip */
if (pinspec.args[0] >= (chip->offset + chip->ngpio))
continue;
if (pinspec.args[0] + pinspec.args[2] <= chip->offset)
continue;
if (pinspec.args[2]) {
/* npins != 0: linear range */
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;
}
}
/* Trim the range to fit this GPIO chip */
if (chip->offset > pinspec.args[0]) {
trim = chip->offset - pinspec.args[0];
pinspec.args[2] -= trim;
pinspec.args[1] += trim;
pinspec.args[0] = 0;
} else {
pinspec.args[0] -= chip->offset;
}
if ((pinspec.args[0] + pinspec.args[2]) > chip->ngpio)
pinspec.args[2] = chip->ngpio - pinspec.args[0];
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));
}
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