linux/drivers/gpio/gpiolib-acpi.c
Linus Torvalds c7d28eca1d This is the bulk of GPIO changes for the v4.13 series:
Core:
 - Export add/remove for lookup tables so that modules can export GPIO
   descriptor tables.
 - Handle GPIO sleep states: it is now possible to flag that a GPIO line
   may loose its state during suspend/resume of the system to save
   power. This is used in the Wolfson Micro Arizona driver.
 - ACPI-based GPIO was tightened up a lot around the edges.
 - Use bitmap_fill() to speed up a loop.
 
 New drivers:
 - Exar XRA1403 SPI-based GPIO.
 - MVEBU driver now supports Armada 7K and 8K.
 - LP87565 PMIC GPIO.
 - Renesas R-CAR R8A7743 (RZ/G1M).
 - The new IOT2040 8250 serial/GPIO also comes in through this
   changeset.
 
 Substantial driver changes:
 - Seriously fix the Exar 8250 GPIO portions to work.
 - The MCP23S08 was moved out to a pin control driver.
 - Convert MEVEBU to use regmap for register access.
 - Drop Vulcan support from the Broadcom driver.
 - Serious cleanup and improvement of the mockup driver, giving us a
   better test coverage.
 
 Misc:
 - Lots of janitorial clean up.
 - A bunch of documentation fixes.
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Merge tag 'gpio-v4.13-1' of git://git.kernel.org/pub/scm/linux/kernel/git/linusw/linux-gpio

Pull GPIO updates from Linus Walleij:
 "This is the bulk of GPIO changes for the v4.13 series.

  Some administrativa:

  I have a slew of 8250 serial patches and the new IOT2040 serial+GPIO
  driver coming in through this tree, along with a whole bunch of Exar
  8250 fixes. These are ACKed by Greg and also hit drivers/platform/*
  where they are ACKed by Andy Shevchenko.

  Speaking about drivers/platform/* there is also a bunch of ACPI stuff
  coming through that route, again ACKed by Andy.

  The MCP23S08 changes are coming in here as well. You already have the
  commits in your tree, so this is just a result of sharing an immutable
  branch between pin control and GPIO.

  Core:
   - Export add/remove for lookup tables so that modules can export GPIO
     descriptor tables.
   - Handle GPIO sleep states: it is now possible to flag that a GPIO
     line may loose its state during suspend/resume of the system to
     save power. This is used in the Wolfson Micro Arizona driver.
   - ACPI-based GPIO was tightened up a lot around the edges.
   - Use bitmap_fill() to speed up a loop.

  New drivers:
   - Exar XRA1403 SPI-based GPIO.
   - MVEBU driver now supports Armada 7K and 8K.
   - LP87565 PMIC GPIO.
   - Renesas R-CAR R8A7743 (RZ/G1M).
   - The new IOT2040 8250 serial/GPIO also comes in through this
     changeset.

  Substantial driver changes:
   - Seriously fix the Exar 8250 GPIO portions to work.
   - The MCP23S08 was moved out to a pin control driver.
   - Convert MEVEBU to use regmap for register access.
   - Drop Vulcan support from the Broadcom driver.
   - Serious cleanup and improvement of the mockup driver, giving us a
     better test coverage.

  Misc:
   - Lots of janitorial clean up.
   - A bunch of documentation fixes"

* tag 'gpio-v4.13-1' of git://git.kernel.org/pub/scm/linux/kernel/git/linusw/linux-gpio: (70 commits)
  serial: exar: Add support for IOT2040 device
  gpio-exar/8250-exar: Make set of exported GPIOs configurable
  platform: Accept const properties
  serial: exar: Factor out platform hooks
  gpio-exar/8250-exar: Rearrange gpiochip parenthood
  gpio: exar: Fix iomap request
  gpio-exar/8250-exar: Do not even instantiate a GPIO device for Commtech cards
  serial: uapi: Add support for bus termination
  gpio: rcar: Add R8A7743 (RZ/G1M) support
  gpio: gpio-wcove: Fix GPIO control register offset calculation
  gpio: lp87565: Add support for GPIO
  gpio: dwapb: fix missing first irq for edgeboth irq type
  MAINTAINERS: Take maintainership for GPIO ACPI support
  gpio: exar: Fix reading of directions and values
  gpio: exar: Allocate resources on behalf of the platform device
  gpio-exar/8250-exar: Fix passing in of parent PCI device
  gpio: mockup: use devm_kcalloc() where applicable
  gpio: mockup: add myself as author
  gpio: mockup: improve the error message
  gpio: mockup: don't return magic numbers from probe()
  ...
2017-07-07 12:40:27 -07:00

1213 lines
30 KiB
C

/*
* ACPI helpers for GPIO API
*
* Copyright (C) 2012, Intel Corporation
* Authors: Mathias Nyman <mathias.nyman@linux.intel.com>
* Mika Westerberg <mika.westerberg@linux.intel.com>
*
* This program is free software; you can redistribute it and/or modify
* it under the terms of the GNU General Public License version 2 as
* published by the Free Software Foundation.
*/
#include <linux/errno.h>
#include <linux/gpio.h>
#include <linux/gpio/consumer.h>
#include <linux/gpio/driver.h>
#include <linux/gpio/machine.h>
#include <linux/export.h>
#include <linux/acpi.h>
#include <linux/interrupt.h>
#include <linux/mutex.h>
#include <linux/pinctrl/pinctrl.h>
#include "gpiolib.h"
struct acpi_gpio_event {
struct list_head node;
acpi_handle handle;
unsigned int pin;
unsigned int irq;
struct gpio_desc *desc;
};
struct acpi_gpio_connection {
struct list_head node;
unsigned int pin;
struct gpio_desc *desc;
};
struct acpi_gpio_chip {
/*
* ACPICA requires that the first field of the context parameter
* passed to acpi_install_address_space_handler() is large enough
* to hold struct acpi_connection_info.
*/
struct acpi_connection_info conn_info;
struct list_head conns;
struct mutex conn_lock;
struct gpio_chip *chip;
struct list_head events;
};
static int acpi_gpiochip_find(struct gpio_chip *gc, void *data)
{
if (!gc->parent)
return false;
return ACPI_HANDLE(gc->parent) == data;
}
#ifdef CONFIG_PINCTRL
/**
* acpi_gpiochip_pin_to_gpio_offset() - translates ACPI GPIO to Linux GPIO
* @chip: GPIO chip
* @pin: ACPI GPIO pin number from GpioIo/GpioInt resource
*
* Function takes ACPI GpioIo/GpioInt pin number as a parameter and
* translates it to a corresponding offset suitable to be passed to a
* GPIO controller driver.
*
* Typically the returned offset is same as @pin, but if the GPIO
* controller uses pin controller and the mapping is not contiguous the
* offset might be different.
*/
static int acpi_gpiochip_pin_to_gpio_offset(struct gpio_device *gdev, int pin)
{
struct gpio_pin_range *pin_range;
/* If there are no ranges in this chip, use 1:1 mapping */
if (list_empty(&gdev->pin_ranges))
return pin;
list_for_each_entry(pin_range, &gdev->pin_ranges, node) {
const struct pinctrl_gpio_range *range = &pin_range->range;
int i;
if (range->pins) {
for (i = 0; i < range->npins; i++) {
if (range->pins[i] == pin)
return range->base + i - gdev->base;
}
} else {
if (pin >= range->pin_base &&
pin < range->pin_base + range->npins) {
unsigned gpio_base;
gpio_base = range->base - gdev->base;
return gpio_base + pin - range->pin_base;
}
}
}
return -EINVAL;
}
#else
static inline int acpi_gpiochip_pin_to_gpio_offset(struct gpio_device *gdev,
int pin)
{
return pin;
}
#endif
/**
* acpi_get_gpiod() - Translate ACPI GPIO pin to GPIO descriptor usable with GPIO API
* @path: ACPI GPIO controller full path name, (e.g. "\\_SB.GPO1")
* @pin: ACPI GPIO pin number (0-based, controller-relative)
*
* Return: GPIO descriptor to use with Linux generic GPIO API, or ERR_PTR
* error value. Specifically returns %-EPROBE_DEFER if the referenced GPIO
* controller does not have gpiochip registered at the moment. This is to
* support probe deferral.
*/
static struct gpio_desc *acpi_get_gpiod(char *path, int pin)
{
struct gpio_chip *chip;
acpi_handle handle;
acpi_status status;
int offset;
status = acpi_get_handle(NULL, path, &handle);
if (ACPI_FAILURE(status))
return ERR_PTR(-ENODEV);
chip = gpiochip_find(handle, acpi_gpiochip_find);
if (!chip)
return ERR_PTR(-EPROBE_DEFER);
offset = acpi_gpiochip_pin_to_gpio_offset(chip->gpiodev, pin);
if (offset < 0)
return ERR_PTR(offset);
return gpiochip_get_desc(chip, offset);
}
static irqreturn_t acpi_gpio_irq_handler(int irq, void *data)
{
struct acpi_gpio_event *event = data;
acpi_evaluate_object(event->handle, NULL, NULL, NULL);
return IRQ_HANDLED;
}
static irqreturn_t acpi_gpio_irq_handler_evt(int irq, void *data)
{
struct acpi_gpio_event *event = data;
acpi_execute_simple_method(event->handle, NULL, event->pin);
return IRQ_HANDLED;
}
static void acpi_gpio_chip_dh(acpi_handle handle, void *data)
{
/* The address of this function is used as a key. */
}
bool acpi_gpio_get_irq_resource(struct acpi_resource *ares,
struct acpi_resource_gpio **agpio)
{
struct acpi_resource_gpio *gpio;
if (ares->type != ACPI_RESOURCE_TYPE_GPIO)
return false;
gpio = &ares->data.gpio;
if (gpio->connection_type != ACPI_RESOURCE_GPIO_TYPE_INT)
return false;
*agpio = gpio;
return true;
}
EXPORT_SYMBOL_GPL(acpi_gpio_get_irq_resource);
static acpi_status acpi_gpiochip_request_interrupt(struct acpi_resource *ares,
void *context)
{
struct acpi_gpio_chip *acpi_gpio = context;
struct gpio_chip *chip = acpi_gpio->chip;
struct acpi_resource_gpio *agpio;
acpi_handle handle, evt_handle;
struct acpi_gpio_event *event;
irq_handler_t handler = NULL;
struct gpio_desc *desc;
unsigned long irqflags;
int ret, pin, irq;
if (!acpi_gpio_get_irq_resource(ares, &agpio))
return AE_OK;
handle = ACPI_HANDLE(chip->parent);
pin = agpio->pin_table[0];
if (pin <= 255) {
char ev_name[5];
sprintf(ev_name, "_%c%02X",
agpio->triggering == ACPI_EDGE_SENSITIVE ? 'E' : 'L',
pin);
if (ACPI_SUCCESS(acpi_get_handle(handle, ev_name, &evt_handle)))
handler = acpi_gpio_irq_handler;
}
if (!handler) {
if (ACPI_SUCCESS(acpi_get_handle(handle, "_EVT", &evt_handle)))
handler = acpi_gpio_irq_handler_evt;
}
if (!handler)
return AE_OK;
pin = acpi_gpiochip_pin_to_gpio_offset(chip->gpiodev, pin);
if (pin < 0)
return AE_BAD_PARAMETER;
desc = gpiochip_request_own_desc(chip, pin, "ACPI:Event");
if (IS_ERR(desc)) {
dev_err(chip->parent, "Failed to request GPIO\n");
return AE_ERROR;
}
gpiod_direction_input(desc);
ret = gpiochip_lock_as_irq(chip, pin);
if (ret) {
dev_err(chip->parent, "Failed to lock GPIO as interrupt\n");
goto fail_free_desc;
}
irq = gpiod_to_irq(desc);
if (irq < 0) {
dev_err(chip->parent, "Failed to translate GPIO to IRQ\n");
goto fail_unlock_irq;
}
irqflags = IRQF_ONESHOT;
if (agpio->triggering == ACPI_LEVEL_SENSITIVE) {
if (agpio->polarity == ACPI_ACTIVE_HIGH)
irqflags |= IRQF_TRIGGER_HIGH;
else
irqflags |= IRQF_TRIGGER_LOW;
} else {
switch (agpio->polarity) {
case ACPI_ACTIVE_HIGH:
irqflags |= IRQF_TRIGGER_RISING;
break;
case ACPI_ACTIVE_LOW:
irqflags |= IRQF_TRIGGER_FALLING;
break;
default:
irqflags |= IRQF_TRIGGER_RISING |
IRQF_TRIGGER_FALLING;
break;
}
}
event = kzalloc(sizeof(*event), GFP_KERNEL);
if (!event)
goto fail_unlock_irq;
event->handle = evt_handle;
event->irq = irq;
event->pin = pin;
event->desc = desc;
ret = request_threaded_irq(event->irq, NULL, handler, irqflags,
"ACPI:Event", event);
if (ret) {
dev_err(chip->parent,
"Failed to setup interrupt handler for %d\n",
event->irq);
goto fail_free_event;
}
if (agpio->wake_capable == ACPI_WAKE_CAPABLE)
enable_irq_wake(irq);
list_add_tail(&event->node, &acpi_gpio->events);
return AE_OK;
fail_free_event:
kfree(event);
fail_unlock_irq:
gpiochip_unlock_as_irq(chip, pin);
fail_free_desc:
gpiochip_free_own_desc(desc);
return AE_ERROR;
}
/**
* acpi_gpiochip_request_interrupts() - Register isr for gpio chip ACPI events
* @chip: GPIO chip
*
* ACPI5 platforms can use GPIO signaled ACPI events. These GPIO interrupts are
* handled by ACPI event methods which need to be called from the GPIO
* chip's interrupt handler. acpi_gpiochip_request_interrupts finds out which
* gpio pins have acpi event methods and assigns interrupt handlers that calls
* the acpi event methods for those pins.
*/
void acpi_gpiochip_request_interrupts(struct gpio_chip *chip)
{
struct acpi_gpio_chip *acpi_gpio;
acpi_handle handle;
acpi_status status;
if (!chip->parent || !chip->to_irq)
return;
handle = ACPI_HANDLE(chip->parent);
if (!handle)
return;
status = acpi_get_data(handle, acpi_gpio_chip_dh, (void **)&acpi_gpio);
if (ACPI_FAILURE(status))
return;
acpi_walk_resources(handle, "_AEI",
acpi_gpiochip_request_interrupt, acpi_gpio);
}
EXPORT_SYMBOL_GPL(acpi_gpiochip_request_interrupts);
/**
* acpi_gpiochip_free_interrupts() - Free GPIO ACPI event interrupts.
* @chip: GPIO chip
*
* Free interrupts associated with GPIO ACPI event method for the given
* GPIO chip.
*/
void acpi_gpiochip_free_interrupts(struct gpio_chip *chip)
{
struct acpi_gpio_chip *acpi_gpio;
struct acpi_gpio_event *event, *ep;
acpi_handle handle;
acpi_status status;
if (!chip->parent || !chip->to_irq)
return;
handle = ACPI_HANDLE(chip->parent);
if (!handle)
return;
status = acpi_get_data(handle, acpi_gpio_chip_dh, (void **)&acpi_gpio);
if (ACPI_FAILURE(status))
return;
list_for_each_entry_safe_reverse(event, ep, &acpi_gpio->events, node) {
struct gpio_desc *desc;
if (irqd_is_wakeup_set(irq_get_irq_data(event->irq)))
disable_irq_wake(event->irq);
free_irq(event->irq, event);
desc = event->desc;
if (WARN_ON(IS_ERR(desc)))
continue;
gpiochip_unlock_as_irq(chip, event->pin);
gpiochip_free_own_desc(desc);
list_del(&event->node);
kfree(event);
}
}
EXPORT_SYMBOL_GPL(acpi_gpiochip_free_interrupts);
int acpi_dev_add_driver_gpios(struct acpi_device *adev,
const struct acpi_gpio_mapping *gpios)
{
if (adev && gpios) {
adev->driver_gpios = gpios;
return 0;
}
return -EINVAL;
}
EXPORT_SYMBOL_GPL(acpi_dev_add_driver_gpios);
static void devm_acpi_dev_release_driver_gpios(struct device *dev, void *res)
{
acpi_dev_remove_driver_gpios(ACPI_COMPANION(dev));
}
int devm_acpi_dev_add_driver_gpios(struct device *dev,
const struct acpi_gpio_mapping *gpios)
{
void *res;
int ret;
res = devres_alloc(devm_acpi_dev_release_driver_gpios, 0, GFP_KERNEL);
if (!res)
return -ENOMEM;
ret = acpi_dev_add_driver_gpios(ACPI_COMPANION(dev), gpios);
if (ret) {
devres_free(res);
return ret;
}
devres_add(dev, res);
return 0;
}
EXPORT_SYMBOL_GPL(devm_acpi_dev_add_driver_gpios);
void devm_acpi_dev_remove_driver_gpios(struct device *dev)
{
WARN_ON(devres_release(dev, devm_acpi_dev_release_driver_gpios, NULL, NULL));
}
EXPORT_SYMBOL_GPL(devm_acpi_dev_remove_driver_gpios);
static bool acpi_get_driver_gpio_data(struct acpi_device *adev,
const char *name, int index,
struct acpi_reference_args *args)
{
const struct acpi_gpio_mapping *gm;
if (!adev->driver_gpios)
return false;
for (gm = adev->driver_gpios; gm->name; gm++)
if (!strcmp(name, gm->name) && gm->data && index < gm->size) {
const struct acpi_gpio_params *par = gm->data + index;
args->adev = adev;
args->args[0] = par->crs_entry_index;
args->args[1] = par->line_index;
args->args[2] = par->active_low;
args->nargs = 3;
return true;
}
return false;
}
static enum gpiod_flags
acpi_gpio_to_gpiod_flags(const struct acpi_resource_gpio *agpio)
{
bool pull_up = agpio->pin_config == ACPI_PIN_CONFIG_PULLUP;
switch (agpio->io_restriction) {
case ACPI_IO_RESTRICT_INPUT:
return GPIOD_IN;
case ACPI_IO_RESTRICT_OUTPUT:
/*
* ACPI GPIO resources don't contain an initial value for the
* GPIO. Therefore we deduce that value from the pull field
* instead. If the pin is pulled up we assume default to be
* high, otherwise low.
*/
return pull_up ? GPIOD_OUT_HIGH : GPIOD_OUT_LOW;
default:
/*
* Assume that the BIOS has configured the direction and pull
* accordingly.
*/
return GPIOD_ASIS;
}
}
int
acpi_gpio_update_gpiod_flags(enum gpiod_flags *flags, enum gpiod_flags update)
{
int ret = 0;
/*
* Check if the BIOS has IoRestriction with explicitly set direction
* and update @flags accordingly. Otherwise use whatever caller asked
* for.
*/
if (update & GPIOD_FLAGS_BIT_DIR_SET) {
enum gpiod_flags diff = *flags ^ update;
/*
* Check if caller supplied incompatible GPIO initialization
* flags.
*
* Return %-EINVAL to notify that firmware has different
* settings and we are going to use them.
*/
if (((*flags & GPIOD_FLAGS_BIT_DIR_SET) && (diff & GPIOD_FLAGS_BIT_DIR_OUT)) ||
((*flags & GPIOD_FLAGS_BIT_DIR_OUT) && (diff & GPIOD_FLAGS_BIT_DIR_VAL)))
ret = -EINVAL;
*flags = update;
}
return ret;
}
struct acpi_gpio_lookup {
struct acpi_gpio_info info;
int index;
int pin_index;
bool active_low;
struct acpi_device *adev;
struct gpio_desc *desc;
int n;
};
static int acpi_populate_gpio_lookup(struct acpi_resource *ares, void *data)
{
struct acpi_gpio_lookup *lookup = data;
if (ares->type != ACPI_RESOURCE_TYPE_GPIO)
return 1;
if (lookup->n++ == lookup->index && !lookup->desc) {
const struct acpi_resource_gpio *agpio = &ares->data.gpio;
int pin_index = lookup->pin_index;
if (pin_index >= agpio->pin_table_length)
return 1;
lookup->desc = acpi_get_gpiod(agpio->resource_source.string_ptr,
agpio->pin_table[pin_index]);
lookup->info.gpioint =
agpio->connection_type == ACPI_RESOURCE_GPIO_TYPE_INT;
/*
* Polarity and triggering are only specified for GpioInt
* resource.
* Note: we expect here:
* - ACPI_ACTIVE_LOW == GPIO_ACTIVE_LOW
* - ACPI_ACTIVE_HIGH == GPIO_ACTIVE_HIGH
*/
if (lookup->info.gpioint) {
lookup->info.flags = GPIOD_IN;
lookup->info.polarity = agpio->polarity;
lookup->info.triggering = agpio->triggering;
} else {
lookup->info.flags = acpi_gpio_to_gpiod_flags(agpio);
}
}
return 1;
}
static int acpi_gpio_resource_lookup(struct acpi_gpio_lookup *lookup,
struct acpi_gpio_info *info)
{
struct list_head res_list;
int ret;
INIT_LIST_HEAD(&res_list);
ret = acpi_dev_get_resources(lookup->adev, &res_list,
acpi_populate_gpio_lookup,
lookup);
if (ret < 0)
return ret;
acpi_dev_free_resource_list(&res_list);
if (!lookup->desc)
return -ENOENT;
if (info) {
*info = lookup->info;
if (lookup->active_low)
info->polarity = lookup->active_low;
}
return 0;
}
static int acpi_gpio_property_lookup(struct fwnode_handle *fwnode,
const char *propname, int index,
struct acpi_gpio_lookup *lookup)
{
struct acpi_reference_args args;
int ret;
memset(&args, 0, sizeof(args));
ret = __acpi_node_get_property_reference(fwnode, propname, index, 3,
&args);
if (ret) {
struct acpi_device *adev = to_acpi_device_node(fwnode);
if (!adev)
return ret;
if (!acpi_get_driver_gpio_data(adev, propname, index, &args))
return ret;
}
/*
* The property was found and resolved, so need to lookup the GPIO based
* on returned args.
*/
lookup->adev = args.adev;
if (args.nargs != 3)
return -EPROTO;
lookup->index = args.args[0];
lookup->pin_index = args.args[1];
lookup->active_low = !!args.args[2];
return 0;
}
/**
* acpi_get_gpiod_by_index() - get a GPIO descriptor from device resources
* @adev: pointer to a ACPI device to get GPIO from
* @propname: Property name of the GPIO (optional)
* @index: index of GpioIo/GpioInt resource (starting from %0)
* @info: info pointer to fill in (optional)
*
* Function goes through ACPI resources for @adev and based on @index looks
* up a GpioIo/GpioInt resource, translates it to the Linux GPIO descriptor,
* and returns it. @index matches GpioIo/GpioInt resources only so if there
* are total %3 GPIO resources, the index goes from %0 to %2.
*
* If @propname is specified the GPIO is looked using device property. In
* that case @index is used to select the GPIO entry in the property value
* (in case of multiple).
*
* If the GPIO cannot be translated or there is an error an ERR_PTR is
* returned.
*
* Note: if the GPIO resource has multiple entries in the pin list, this
* function only returns the first.
*/
static struct gpio_desc *acpi_get_gpiod_by_index(struct acpi_device *adev,
const char *propname, int index,
struct acpi_gpio_info *info)
{
struct acpi_gpio_lookup lookup;
int ret;
if (!adev)
return ERR_PTR(-ENODEV);
memset(&lookup, 0, sizeof(lookup));
lookup.index = index;
if (propname) {
dev_dbg(&adev->dev, "GPIO: looking up %s\n", propname);
ret = acpi_gpio_property_lookup(acpi_fwnode_handle(adev),
propname, index, &lookup);
if (ret)
return ERR_PTR(ret);
dev_dbg(&adev->dev, "GPIO: _DSD returned %s %d %d %u\n",
dev_name(&lookup.adev->dev), lookup.index,
lookup.pin_index, lookup.active_low);
} else {
dev_dbg(&adev->dev, "GPIO: looking up %d in _CRS\n", index);
lookup.adev = adev;
}
ret = acpi_gpio_resource_lookup(&lookup, info);
return ret ? ERR_PTR(ret) : lookup.desc;
}
struct gpio_desc *acpi_find_gpio(struct device *dev,
const char *con_id,
unsigned int idx,
enum gpiod_flags *dflags,
enum gpio_lookup_flags *lookupflags)
{
struct acpi_device *adev = ACPI_COMPANION(dev);
struct acpi_gpio_info info;
struct gpio_desc *desc;
char propname[32];
int err;
int i;
/* Try first from _DSD */
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]);
}
desc = acpi_get_gpiod_by_index(adev, propname, idx, &info);
if (!IS_ERR(desc))
break;
if (PTR_ERR(desc) == -EPROBE_DEFER)
return ERR_CAST(desc);
}
/* Then from plain _CRS GPIOs */
if (IS_ERR(desc)) {
if (!acpi_can_fallback_to_crs(adev, con_id))
return ERR_PTR(-ENOENT);
desc = acpi_get_gpiod_by_index(adev, NULL, idx, &info);
if (IS_ERR(desc))
return desc;
}
if (info.gpioint &&
(*dflags == GPIOD_OUT_LOW || *dflags == GPIOD_OUT_HIGH)) {
dev_dbg(dev, "refusing GpioInt() entry when doing GPIOD_OUT_* lookup\n");
return ERR_PTR(-ENOENT);
}
if (info.polarity == GPIO_ACTIVE_LOW)
*lookupflags |= GPIO_ACTIVE_LOW;
err = acpi_gpio_update_gpiod_flags(dflags, info.flags);
if (err)
dev_dbg(dev, "Override GPIO initialization flags\n");
return desc;
}
/**
* acpi_node_get_gpiod() - get a GPIO descriptor from ACPI resources
* @fwnode: pointer to an ACPI firmware node to get the GPIO information from
* @propname: Property name of the GPIO
* @index: index of GpioIo/GpioInt resource (starting from %0)
* @info: info pointer to fill in (optional)
*
* If @fwnode is an ACPI device object, call %acpi_get_gpiod_by_index() for it.
* Otherwise (ie. it is a data-only non-device object), use the property-based
* GPIO lookup to get to the GPIO resource with the relevant information and use
* that to obtain the GPIO descriptor to return.
*/
struct gpio_desc *acpi_node_get_gpiod(struct fwnode_handle *fwnode,
const char *propname, int index,
struct acpi_gpio_info *info)
{
struct acpi_gpio_lookup lookup;
struct acpi_device *adev;
int ret;
adev = to_acpi_device_node(fwnode);
if (adev)
return acpi_get_gpiod_by_index(adev, propname, index, info);
if (!is_acpi_data_node(fwnode))
return ERR_PTR(-ENODEV);
if (!propname)
return ERR_PTR(-EINVAL);
memset(&lookup, 0, sizeof(lookup));
lookup.index = index;
ret = acpi_gpio_property_lookup(fwnode, propname, index, &lookup);
if (ret)
return ERR_PTR(ret);
ret = acpi_gpio_resource_lookup(&lookup, info);
return ret ? ERR_PTR(ret) : lookup.desc;
}
/**
* acpi_dev_gpio_irq_get() - Find GpioInt and translate it to Linux IRQ number
* @adev: pointer to a ACPI device to get IRQ from
* @index: index of GpioInt resource (starting from %0)
*
* If the device has one or more GpioInt resources, this function can be
* used to translate from the GPIO offset in the resource to the Linux IRQ
* number.
*
* The function is idempotent, though each time it runs it will configure GPIO
* pin direction according to the flags in GpioInt resource.
*
* Return: Linux IRQ number (>%0) on success, negative errno on failure.
*/
int acpi_dev_gpio_irq_get(struct acpi_device *adev, int index)
{
int idx, i;
unsigned int irq_flags;
int ret;
for (i = 0, idx = 0; idx <= index; i++) {
struct acpi_gpio_info info;
struct gpio_desc *desc;
desc = acpi_get_gpiod_by_index(adev, NULL, i, &info);
/* Ignore -EPROBE_DEFER, it only matters if idx matches */
if (IS_ERR(desc) && PTR_ERR(desc) != -EPROBE_DEFER)
return PTR_ERR(desc);
if (info.gpioint && idx++ == index) {
char label[32];
int irq;
if (IS_ERR(desc))
return PTR_ERR(desc);
irq = gpiod_to_irq(desc);
if (irq < 0)
return irq;
snprintf(label, sizeof(label), "GpioInt() %d", index);
ret = gpiod_configure_flags(desc, label, 0, info.flags);
if (ret < 0)
return ret;
irq_flags = acpi_dev_get_irq_type(info.triggering,
info.polarity);
/* Set type if specified and different than the current one */
if (irq_flags != IRQ_TYPE_NONE &&
irq_flags != irq_get_trigger_type(irq))
irq_set_irq_type(irq, irq_flags);
return irq;
}
}
return -ENOENT;
}
EXPORT_SYMBOL_GPL(acpi_dev_gpio_irq_get);
static acpi_status
acpi_gpio_adr_space_handler(u32 function, acpi_physical_address address,
u32 bits, u64 *value, void *handler_context,
void *region_context)
{
struct acpi_gpio_chip *achip = region_context;
struct gpio_chip *chip = achip->chip;
struct acpi_resource_gpio *agpio;
struct acpi_resource *ares;
int pin_index = (int)address;
acpi_status status;
int length;
int i;
status = acpi_buffer_to_resource(achip->conn_info.connection,
achip->conn_info.length, &ares);
if (ACPI_FAILURE(status))
return status;
if (WARN_ON(ares->type != ACPI_RESOURCE_TYPE_GPIO)) {
ACPI_FREE(ares);
return AE_BAD_PARAMETER;
}
agpio = &ares->data.gpio;
if (WARN_ON(agpio->io_restriction == ACPI_IO_RESTRICT_INPUT &&
function == ACPI_WRITE)) {
ACPI_FREE(ares);
return AE_BAD_PARAMETER;
}
length = min(agpio->pin_table_length, (u16)(pin_index + bits));
for (i = pin_index; i < length; ++i) {
int pin = agpio->pin_table[i];
struct acpi_gpio_connection *conn;
struct gpio_desc *desc;
bool found;
pin = acpi_gpiochip_pin_to_gpio_offset(chip->gpiodev, pin);
if (pin < 0) {
status = AE_BAD_PARAMETER;
goto out;
}
mutex_lock(&achip->conn_lock);
found = false;
list_for_each_entry(conn, &achip->conns, node) {
if (conn->pin == pin) {
found = true;
desc = conn->desc;
break;
}
}
/*
* The same GPIO can be shared between operation region and
* event but only if the access here is ACPI_READ. In that
* case we "borrow" the event GPIO instead.
*/
if (!found && agpio->sharable == ACPI_SHARED &&
function == ACPI_READ) {
struct acpi_gpio_event *event;
list_for_each_entry(event, &achip->events, node) {
if (event->pin == pin) {
desc = event->desc;
found = true;
break;
}
}
}
if (!found) {
enum gpiod_flags flags = acpi_gpio_to_gpiod_flags(agpio);
const char *label = "ACPI:OpRegion";
int err;
desc = gpiochip_request_own_desc(chip, pin, label);
if (IS_ERR(desc)) {
status = AE_ERROR;
mutex_unlock(&achip->conn_lock);
goto out;
}
err = gpiod_configure_flags(desc, label, 0, flags);
if (err < 0) {
status = AE_NOT_CONFIGURED;
gpiochip_free_own_desc(desc);
mutex_unlock(&achip->conn_lock);
goto out;
}
conn = kzalloc(sizeof(*conn), GFP_KERNEL);
if (!conn) {
status = AE_NO_MEMORY;
gpiochip_free_own_desc(desc);
mutex_unlock(&achip->conn_lock);
goto out;
}
conn->pin = pin;
conn->desc = desc;
list_add_tail(&conn->node, &achip->conns);
}
mutex_unlock(&achip->conn_lock);
if (function == ACPI_WRITE)
gpiod_set_raw_value_cansleep(desc,
!!((1 << i) & *value));
else
*value |= (u64)gpiod_get_raw_value_cansleep(desc) << i;
}
out:
ACPI_FREE(ares);
return status;
}
static void acpi_gpiochip_request_regions(struct acpi_gpio_chip *achip)
{
struct gpio_chip *chip = achip->chip;
acpi_handle handle = ACPI_HANDLE(chip->parent);
acpi_status status;
INIT_LIST_HEAD(&achip->conns);
mutex_init(&achip->conn_lock);
status = acpi_install_address_space_handler(handle, ACPI_ADR_SPACE_GPIO,
acpi_gpio_adr_space_handler,
NULL, achip);
if (ACPI_FAILURE(status))
dev_err(chip->parent,
"Failed to install GPIO OpRegion handler\n");
}
static void acpi_gpiochip_free_regions(struct acpi_gpio_chip *achip)
{
struct gpio_chip *chip = achip->chip;
acpi_handle handle = ACPI_HANDLE(chip->parent);
struct acpi_gpio_connection *conn, *tmp;
acpi_status status;
status = acpi_remove_address_space_handler(handle, ACPI_ADR_SPACE_GPIO,
acpi_gpio_adr_space_handler);
if (ACPI_FAILURE(status)) {
dev_err(chip->parent,
"Failed to remove GPIO OpRegion handler\n");
return;
}
list_for_each_entry_safe_reverse(conn, tmp, &achip->conns, node) {
gpiochip_free_own_desc(conn->desc);
list_del(&conn->node);
kfree(conn);
}
}
static struct gpio_desc *acpi_gpiochip_parse_own_gpio(
struct acpi_gpio_chip *achip, struct fwnode_handle *fwnode,
const char **name, unsigned int *lflags, unsigned int *dflags)
{
struct gpio_chip *chip = achip->chip;
struct gpio_desc *desc;
u32 gpios[2];
int ret;
*lflags = 0;
*dflags = 0;
*name = NULL;
ret = fwnode_property_read_u32_array(fwnode, "gpios", gpios,
ARRAY_SIZE(gpios));
if (ret < 0)
return ERR_PTR(ret);
ret = acpi_gpiochip_pin_to_gpio_offset(chip->gpiodev, gpios[0]);
if (ret < 0)
return ERR_PTR(ret);
desc = gpiochip_get_desc(chip, ret);
if (IS_ERR(desc))
return desc;
if (gpios[1])
*lflags |= GPIO_ACTIVE_LOW;
if (fwnode_property_present(fwnode, "input"))
*dflags |= GPIOD_IN;
else if (fwnode_property_present(fwnode, "output-low"))
*dflags |= GPIOD_OUT_LOW;
else if (fwnode_property_present(fwnode, "output-high"))
*dflags |= GPIOD_OUT_HIGH;
else
return ERR_PTR(-EINVAL);
fwnode_property_read_string(fwnode, "line-name", name);
return desc;
}
static void acpi_gpiochip_scan_gpios(struct acpi_gpio_chip *achip)
{
struct gpio_chip *chip = achip->chip;
struct fwnode_handle *fwnode;
device_for_each_child_node(chip->parent, fwnode) {
unsigned int lflags, dflags;
struct gpio_desc *desc;
const char *name;
int ret;
if (!fwnode_property_present(fwnode, "gpio-hog"))
continue;
desc = acpi_gpiochip_parse_own_gpio(achip, fwnode, &name,
&lflags, &dflags);
if (IS_ERR(desc))
continue;
ret = gpiod_hog(desc, name, lflags, dflags);
if (ret) {
dev_err(chip->parent, "Failed to hog GPIO\n");
fwnode_handle_put(fwnode);
return;
}
}
}
void acpi_gpiochip_add(struct gpio_chip *chip)
{
struct acpi_gpio_chip *acpi_gpio;
acpi_handle handle;
acpi_status status;
if (!chip || !chip->parent)
return;
handle = ACPI_HANDLE(chip->parent);
if (!handle)
return;
acpi_gpio = kzalloc(sizeof(*acpi_gpio), GFP_KERNEL);
if (!acpi_gpio) {
dev_err(chip->parent,
"Failed to allocate memory for ACPI GPIO chip\n");
return;
}
acpi_gpio->chip = chip;
INIT_LIST_HEAD(&acpi_gpio->events);
status = acpi_attach_data(handle, acpi_gpio_chip_dh, acpi_gpio);
if (ACPI_FAILURE(status)) {
dev_err(chip->parent, "Failed to attach ACPI GPIO chip\n");
kfree(acpi_gpio);
return;
}
if (!chip->names)
devprop_gpiochip_set_names(chip);
acpi_gpiochip_request_regions(acpi_gpio);
acpi_gpiochip_scan_gpios(acpi_gpio);
acpi_walk_dep_device_list(handle);
}
void acpi_gpiochip_remove(struct gpio_chip *chip)
{
struct acpi_gpio_chip *acpi_gpio;
acpi_handle handle;
acpi_status status;
if (!chip || !chip->parent)
return;
handle = ACPI_HANDLE(chip->parent);
if (!handle)
return;
status = acpi_get_data(handle, acpi_gpio_chip_dh, (void **)&acpi_gpio);
if (ACPI_FAILURE(status)) {
dev_warn(chip->parent, "Failed to retrieve ACPI GPIO chip\n");
return;
}
acpi_gpiochip_free_regions(acpi_gpio);
acpi_detach_data(handle, acpi_gpio_chip_dh);
kfree(acpi_gpio);
}
static int acpi_gpio_package_count(const union acpi_object *obj)
{
const union acpi_object *element = obj->package.elements;
const union acpi_object *end = element + obj->package.count;
unsigned int count = 0;
while (element < end) {
switch (element->type) {
case ACPI_TYPE_LOCAL_REFERENCE:
element += 3;
/* Fallthrough */
case ACPI_TYPE_INTEGER:
element++;
count++;
break;
default:
return -EPROTO;
}
}
return count;
}
static int acpi_find_gpio_count(struct acpi_resource *ares, void *data)
{
unsigned int *count = data;
if (ares->type == ACPI_RESOURCE_TYPE_GPIO)
*count += ares->data.gpio.pin_table_length;
return 1;
}
/**
* acpi_gpio_count - return the number of GPIOs associated with a
* device / function or -ENOENT if no GPIO has been
* assigned to the requested function.
* @dev: GPIO consumer, can be NULL for system-global GPIOs
* @con_id: function within the GPIO consumer
*/
int acpi_gpio_count(struct device *dev, const char *con_id)
{
struct acpi_device *adev = ACPI_COMPANION(dev);
const union acpi_object *obj;
const struct acpi_gpio_mapping *gm;
int count = -ENOENT;
int ret;
char propname[32];
unsigned int i;
/* Try first from _DSD */
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 = acpi_dev_get_property(adev, propname, ACPI_TYPE_ANY,
&obj);
if (ret == 0) {
if (obj->type == ACPI_TYPE_LOCAL_REFERENCE)
count = 1;
else if (obj->type == ACPI_TYPE_PACKAGE)
count = acpi_gpio_package_count(obj);
} else if (adev->driver_gpios) {
for (gm = adev->driver_gpios; gm->name; gm++)
if (strcmp(propname, gm->name) == 0) {
count = gm->size;
break;
}
}
if (count > 0)
break;
}
/* Then from plain _CRS GPIOs */
if (count < 0) {
struct list_head resource_list;
unsigned int crs_count = 0;
if (!acpi_can_fallback_to_crs(adev, con_id))
return count;
INIT_LIST_HEAD(&resource_list);
acpi_dev_get_resources(adev, &resource_list,
acpi_find_gpio_count, &crs_count);
acpi_dev_free_resource_list(&resource_list);
if (crs_count > 0)
count = crs_count;
}
return count ? count : -ENOENT;
}
bool acpi_can_fallback_to_crs(struct acpi_device *adev, const char *con_id)
{
/* Never allow fallback if the device has properties */
if (adev->data.properties || adev->driver_gpios)
return false;
return con_id == NULL;
}