linux/drivers/gpio/gpiolib-of.c
Linus Torvalds a922f1a9ae spi: Fixes for v5.5
A relatively large set of fixes here, the biggest part of it is for
 fallout from the GPIO descriptor rework that affected several of the
 devices with usable native chip select support.  There's also some new
 PCI IDs for Intel Jasper Lake devices.
 
 The conversion to platform_get_irq() in the fsl driver is an incremental
 fix for build errors introduced on SPARC by the earlier fix for error
 handling in probe in that driver.
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Merge tag 'spi-fix-v5.5-rc2' of git://git.kernel.org/pub/scm/linux/kernel/git/broonie/spi

Pull spi fixes from Mark Brown:
 "A relatively large set of fixes here, the biggest part of it is for
  fallout from the GPIO descriptor rework that affected several of the
  devices with usable native chip select support. There's also some new
  PCI IDs for Intel Jasper Lake devices.

  The conversion to platform_get_irq() in the fsl driver is an
  incremental fix for build errors introduced on SPARC by the earlier
  fix for error handling in probe in that driver"

* tag 'spi-fix-v5.5-rc2' of git://git.kernel.org/pub/scm/linux/kernel/git/broonie/spi:
  spi: fsl: use platform_get_irq() instead of of_irq_to_resource()
  spi: nxp-fspi: Ensure width is respected in spi-mem operations
  spi: spi-ti-qspi: Fix a bug when accessing non default CS
  spi: fsl: don't map irq during probe
  spi: spi-cavium-thunderx: Add missing pci_release_regions()
  spi: sprd: Fix the incorrect SPI register
  gpiolib: of: Make of_gpio_spi_cs_get_count static
  spi: fsl: Handle the single hardwired chipselect case
  gpio: Handle counting of Freescale chipselects
  spi: fsl: Fix GPIO descriptor support
  spi: dw: Correct handling of native chipselect
  spi: cadence: Correct handling of native chipselect
  spi: pxa2xx: Add support for Intel Jasper Lake
2019-12-17 13:06:31 -08:00

925 lines
24 KiB
C

// 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)
{
/*
* Handle MMC "cd-inverted" and "wp-inverted" semantics.
*/
if (IS_ENABLED(CONFIG_MMC)) {
/*
* Active low is the default according to the
* SDHCI specification and the device tree
* bindings. However the code in the current
* kernel was written such that the phandle
* flags were always respected, and "cd-inverted"
* would invert the flag from the device phandle.
*/
if (!strcmp(propname, "cd-gpios")) {
if (of_property_read_bool(np, "cd-inverted"))
*flags ^= OF_GPIO_ACTIVE_LOW;
}
if (!strcmp(propname, "wp-gpios")) {
if (of_property_read_bool(np, "wp-inverted"))
*flags ^= OF_GPIO_ACTIVE_LOW;
}
}
/*
* 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;
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 devices */
if (!of_device_is_compatible(np, "fsl,spi") &&
!of_device_is_compatible(np, "aeroflexgaisler,spictrl"))
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);
}
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 (IS_ERR(desc) && PTR_ERR(desc) == -ENOENT) {
/* Special handling for SPI GPIOs if used */
desc = of_find_spi_gpio(dev, con_id, &of_flags);
}
if (IS_ERR(desc) && 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 (IS_ERR(desc) && PTR_ERR(desc) == -ENOENT) {
/* Special handling for regulator GPIOs if used */
desc = of_find_regulator_gpio(dev, con_id, &of_flags);
}
if (IS_ERR(desc) && PTR_ERR(desc) == -ENOENT)
desc = of_find_arizona_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 (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_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 gpio_desc *desc = NULL;
struct device_node *np;
const char *name;
unsigned long lflags;
enum gpiod_flags dflags;
unsigned int i;
int ret;
for_each_available_child_of_node(chip->of_node, np) {
if (!of_property_read_bool(np, "gpio-hog"))
continue;
for (i = 0;; i++) {
desc = of_parse_own_gpio(np, chip, i, &name, &lflags,
&dflags);
if (IS_ERR(desc))
break;
ret = gpiod_hog(desc, name, lflags, dflags);
if (ret < 0) {
of_node_put(np);
return ret;
}
}
}
return 0;
}
/**
* 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;
/* If the chip defines names itself, these take precedence */
if (!chip->names)
devprop_gpiochip_set_names(chip,
of_fwnode_handle(chip->of_node));
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);
}