diff --git a/Documentation/admin-guide/gpio/gpio-aggregator.rst b/Documentation/admin-guide/gpio/gpio-aggregator.rst
new file mode 100644
index 0000000000000000000000000000000000000000..5cd1e7221756504c3c0fd4cba5ac6aa4e2329f12
--- /dev/null
+++ b/Documentation/admin-guide/gpio/gpio-aggregator.rst
@@ -0,0 +1,111 @@
+.. SPDX-License-Identifier: GPL-2.0-only
+
+GPIO Aggregator
+===============
+
+The GPIO Aggregator provides a mechanism to aggregate GPIOs, and expose them as
+a new gpio_chip. This supports the following use cases.
+
+
+Aggregating GPIOs using Sysfs
+-----------------------------
+
+GPIO controllers are exported to userspace using /dev/gpiochip* character
+devices. Access control to these devices is provided by standard UNIX file
+system permissions, on an all-or-nothing basis: either a GPIO controller is
+accessible for a user, or it is not.
+
+The GPIO Aggregator provides access control for a set of one or more GPIOs, by
+aggregating them into a new gpio_chip, which can be assigned to a group or user
+using standard UNIX file ownership and permissions. Furthermore, this
+simplifies and hardens exporting GPIOs to a virtual machine, as the VM can just
+grab the full GPIO controller, and no longer needs to care about which GPIOs to
+grab and which not, reducing the attack surface.
+
+Aggregated GPIO controllers are instantiated and destroyed by writing to
+write-only attribute files in sysfs.
+
+ /sys/bus/platform/drivers/gpio-aggregator/
+
+ "new_device" ...
+ Userspace may ask the kernel to instantiate an aggregated GPIO
+ controller by writing a string describing the GPIOs to
+ aggregate to the "new_device" file, using the format
+
+ .. code-block:: none
+
+ [<gpioA>] [<gpiochipB> <offsets>] ...
+
+ Where:
+
+ "<gpioA>" ...
+ is a GPIO line name,
+
+ "<gpiochipB>" ...
+ is a GPIO chip label, and
+
+ "<offsets>" ...
+ is a comma-separated list of GPIO offsets and/or
+ GPIO offset ranges denoted by dashes.
+
+ Example: Instantiate a new GPIO aggregator by aggregating GPIO
+ line 19 of "e6052000.gpio" and GPIO lines 20-21 of
+ "e6050000.gpio" into a new gpio_chip:
+
+ .. code-block:: sh
+
+ $ echo 'e6052000.gpio 19 e6050000.gpio 20-21' > new_device
+
+ "delete_device" ...
+ Userspace may ask the kernel to destroy an aggregated GPIO
+ controller after use by writing its device name to the
+ "delete_device" file.
+
+ Example: Destroy the previously-created aggregated GPIO
+ controller, assumed to be "gpio-aggregator.0":
+
+ .. code-block:: sh
+
+ $ echo gpio-aggregator.0 > delete_device
+
+
+Generic GPIO Driver
+-------------------
+
+The GPIO Aggregator can also be used as a generic driver for a simple
+GPIO-operated device described in DT, without a dedicated in-kernel driver.
+This is useful in industrial control, and is not unlike e.g. spidev, which
+allows the user to communicate with an SPI device from userspace.
+
+Binding a device to the GPIO Aggregator is performed either by modifying the
+gpio-aggregator driver, or by writing to the "driver_override" file in Sysfs.
+
+Example: If "door" is a GPIO-operated device described in DT, using its own
+compatible value::
+
+ door {
+ compatible = "myvendor,mydoor";
+
+ gpios = <&gpio2 19 GPIO_ACTIVE_HIGH>,
+ <&gpio2 20 GPIO_ACTIVE_LOW>;
+ gpio-line-names = "open", "lock";
+ };
+
+it can be bound to the GPIO Aggregator by either:
+
+1. Adding its compatible value to ``gpio_aggregator_dt_ids[]``,
+2. Binding manually using "driver_override":
+
+.. code-block:: sh
+
+ $ echo gpio-aggregator > /sys/bus/platform/devices/door/driver_override
+ $ echo door > /sys/bus/platform/drivers/gpio-aggregator/bind
+
+After that, a new gpiochip "door" has been created:
+
+.. code-block:: sh
+
+ $ gpioinfo door
+ gpiochip12 - 2 lines:
+ line 0: "open" unused input active-high
+ line 1: "lock" unused input active-high
diff --git a/Documentation/admin-guide/gpio/index.rst b/Documentation/admin-guide/gpio/index.rst
index a244ba4e87d5398ae099eaa0fabfdcac695c8ab1..ef2838638e96777752f91bc9154804bedb4fa24a 100644
--- a/Documentation/admin-guide/gpio/index.rst
+++ b/Documentation/admin-guide/gpio/index.rst
@@ -7,6 +7,7 @@ gpio
.. toctree::
:maxdepth: 1
+ gpio-aggregator
sysfs
.. only:: subproject and html
diff --git a/Documentation/driver-api/gpio/board.rst b/Documentation/driver-api/gpio/board.rst
index ce91518bf9f48ded9e8ff0947f38f16abdd890ae..191fa867826a45c3b3bf815bb38c2b5085377b23 100644
--- a/Documentation/driver-api/gpio/board.rst
+++ b/Documentation/driver-api/gpio/board.rst
@@ -113,13 +113,15 @@ files that desire to do so need to include the following header::
GPIOs are mapped by the means of tables of lookups, containing instances of the
gpiod_lookup structure. Two macros are defined to help declaring such mappings::
- GPIO_LOOKUP(chip_label, chip_hwnum, con_id, flags)
- GPIO_LOOKUP_IDX(chip_label, chip_hwnum, con_id, idx, flags)
+ GPIO_LOOKUP(key, chip_hwnum, con_id, flags)
+ GPIO_LOOKUP_IDX(key, chip_hwnum, con_id, idx, flags)
where
- - chip_label is the label of the gpiod_chip instance providing the GPIO
- - chip_hwnum is the hardware number of the GPIO within the chip
+ - key is either the label of the gpiod_chip instance providing the GPIO, or
+ the GPIO line name
+ - chip_hwnum is the hardware number of the GPIO within the chip, or U16_MAX
+ to indicate that key is a GPIO line name
- con_id is the name of the GPIO function from the device point of view. It
can be NULL, in which case it will match any function.
- idx is the index of the GPIO within the function.
@@ -135,7 +137,10 @@ where
In the future, these flags might be extended to support more properties.
-Note that GPIO_LOOKUP() is just a shortcut to GPIO_LOOKUP_IDX() where idx = 0.
+Note that:
+ 1. GPIO line names are not guaranteed to be globally unique, so the first
+ match found will be used.
+ 2. GPIO_LOOKUP() is just a shortcut to GPIO_LOOKUP_IDX() where idx = 0.
A lookup table can then be defined as follows, with an empty entry defining its
end. The 'dev_id' field of the table is the identifier of the device that will
diff --git a/MAINTAINERS b/MAINTAINERS
index 4306b329987d4fcc51db734a09e79b8ffb990de3..47c601338776cad1172659cde0c9c3fa9abd1750 100644
--- a/MAINTAINERS
+++ b/MAINTAINERS
@@ -7228,6 +7228,13 @@ F: Documentation/firmware-guide/acpi/gpio-properties.rst
F: drivers/gpio/gpiolib-acpi.c
F: drivers/gpio/gpiolib-acpi.h
+GPIO AGGREGATOR
+M: Geert Uytterhoeven <geert+renesas@glider.be>
+L: linux-gpio@vger.kernel.org
+S: Supported
+F: Documentation/admin-guide/gpio/gpio-aggregator.rst
+F: drivers/gpio/gpio-aggregator.c
+
GPIO IR Transmitter
M: Sean Young <sean@mess.org>
L: linux-media@vger.kernel.org
diff --git a/drivers/gpio/Kconfig b/drivers/gpio/Kconfig
index 8fc7893fba2b94dbe1803fcdbffb455f49e7884d..03c01f4aa316efbd1fdb2a64f656f66e36dfdaab 100644
--- a/drivers/gpio/Kconfig
+++ b/drivers/gpio/Kconfig
@@ -1541,6 +1541,18 @@ config GPIO_VIPERBOARD
endmenu
+config GPIO_AGGREGATOR
+ tristate "GPIO Aggregator"
+ help
+ Say yes here to enable the GPIO Aggregator, which provides a way to
+ aggregate existing GPIO lines into a new virtual GPIO chip.
+ This can serve the following purposes:
+ - Assign permissions for a collection of GPIO lines to a user,
+ - Export a collection of GPIO lines to a virtual machine,
+ - Provide a generic driver for a GPIO-operated device in an
+ industrial control context, to be operated from userspace using
+ the GPIO chardev interface.
+
config GPIO_MOCKUP
tristate "GPIO Testing Driver"
select IRQ_SIM
diff --git a/drivers/gpio/Makefile b/drivers/gpio/Makefile
index b2cfc21a97f3e52b5fa8aa58d8afc34f753943eb..65bf3940e33cf73447880d9bce4bb717c3f97107 100644
--- a/drivers/gpio/Makefile
+++ b/drivers/gpio/Makefile
@@ -25,6 +25,7 @@ obj-$(CONFIG_GPIO_74XX_MMIO) += gpio-74xx-mmio.o
obj-$(CONFIG_GPIO_ADNP) += gpio-adnp.o
obj-$(CONFIG_GPIO_ADP5520) += gpio-adp5520.o
obj-$(CONFIG_GPIO_ADP5588) += gpio-adp5588.o
+obj-$(CONFIG_GPIO_AGGREGATOR) += gpio-aggregator.o
obj-$(CONFIG_GPIO_ALTERA_A10SR) += gpio-altera-a10sr.o
obj-$(CONFIG_GPIO_ALTERA) += gpio-altera.o
obj-$(CONFIG_GPIO_AMD8111) += gpio-amd8111.o
diff --git a/drivers/gpio/gpio-aggregator.c b/drivers/gpio/gpio-aggregator.c
new file mode 100644
index 0000000000000000000000000000000000000000..9b0adbdddbfccb300a4847e216b46730d57cd104
--- /dev/null
+++ b/drivers/gpio/gpio-aggregator.c
@@ -0,0 +1,568 @@
+// SPDX-License-Identifier: GPL-2.0-only
+//
+// GPIO Aggregator
+//
+// Copyright (C) 2019-2020 Glider bv
+
+#define DRV_NAME "gpio-aggregator"
+#define pr_fmt(fmt) DRV_NAME ": " fmt
+
+#include <linux/bitmap.h>
+#include <linux/bitops.h>
+#include <linux/ctype.h>
+#include <linux/gpio/consumer.h>
+#include <linux/gpio/driver.h>
+#include <linux/gpio/machine.h>
+#include <linux/idr.h>
+#include <linux/kernel.h>
+#include <linux/module.h>
+#include <linux/mutex.h>
+#include <linux/overflow.h>
+#include <linux/platform_device.h>
+#include <linux/spinlock.h>
+#include <linux/string.h>
+
+
+/*
+ * GPIO Aggregator sysfs interface
+ */
+
+struct gpio_aggregator {
+ struct gpiod_lookup_table *lookups;
+ struct platform_device *pdev;
+ char args[];
+};
+
+static DEFINE_MUTEX(gpio_aggregator_lock); /* protects idr */
+static DEFINE_IDR(gpio_aggregator_idr);
+
+static char *get_arg(char **args)
+{
+ char *start = *args, *end;
+
+ start = skip_spaces(start);
+ if (!*start)
+ return NULL;
+
+ if (*start == '"') {
+ /* Quoted arg */
+ end = strchr(++start, '"');
+ if (!end)
+ return ERR_PTR(-EINVAL);
+ } else {
+ /* Unquoted arg */
+ for (end = start; *end && !isspace(*end); end++) ;
+ }
+
+ if (*end)
+ *end++ = '\0';
+
+ *args = end;
+ return start;
+}
+
+static bool isrange(const char *s)
+{
+ size_t n;
+
+ if (IS_ERR_OR_NULL(s))
+ return false;
+
+ while (1) {
+ n = strspn(s, "0123456789");
+ if (!n)
+ return false;
+
+ s += n;
+
+ switch (*s++) {
+ case '\0':
+ return true;
+
+ case '-':
+ case ',':
+ break;
+
+ default:
+ return false;
+ }
+ }
+}
+
+static int aggr_add_gpio(struct gpio_aggregator *aggr, const char *key,
+ int hwnum, unsigned int *n)
+{
+ struct gpiod_lookup_table *lookups;
+
+ lookups = krealloc(aggr->lookups, struct_size(lookups, table, *n + 2),
+ GFP_KERNEL);
+ if (!lookups)
+ return -ENOMEM;
+
+ lookups->table[*n] =
+ (struct gpiod_lookup)GPIO_LOOKUP_IDX(key, hwnum, NULL, *n, 0);
+
+ (*n)++;
+ memset(&lookups->table[*n], 0, sizeof(lookups->table[*n]));
+
+ aggr->lookups = lookups;
+ return 0;
+}
+
+static int aggr_parse(struct gpio_aggregator *aggr)
+{
+ unsigned int first_index, last_index, i, n = 0;
+ char *name, *offsets, *first, *last, *next;
+ char *args = aggr->args;
+ int error;
+
+ for (name = get_arg(&args), offsets = get_arg(&args); name;
+ offsets = get_arg(&args)) {
+ if (IS_ERR(name)) {
+ pr_err("Cannot get GPIO specifier: %pe\n", name);
+ return PTR_ERR(name);
+ }
+
+ if (!isrange(offsets)) {
+ /* Named GPIO line */
+ error = aggr_add_gpio(aggr, name, U16_MAX, &n);
+ if (error)
+ return error;
+
+ name = offsets;
+ continue;
+ }
+
+ /* GPIO chip + offset(s) */
+ for (first = offsets; *first; first = next) {
+ next = strchrnul(first, ',');
+ if (*next)
+ *next++ = '\0';
+
+ last = strchr(first, '-');
+ if (last)
+ *last++ = '\0';
+
+ if (kstrtouint(first, 10, &first_index)) {
+ pr_err("Cannot parse GPIO index %s\n", first);
+ return -EINVAL;
+ }
+
+ if (!last) {
+ last_index = first_index;
+ } else if (kstrtouint(last, 10, &last_index)) {
+ pr_err("Cannot parse GPIO index %s\n", last);
+ return -EINVAL;
+ }
+
+ for (i = first_index; i <= last_index; i++) {
+ error = aggr_add_gpio(aggr, name, i, &n);
+ if (error)
+ return error;
+ }
+ }
+
+ name = get_arg(&args);
+ }
+
+ if (!n) {
+ pr_err("No GPIOs specified\n");
+ return -EINVAL;
+ }
+
+ return 0;
+}
+
+static ssize_t new_device_store(struct device_driver *driver, const char *buf,
+ size_t count)
+{
+ struct gpio_aggregator *aggr;
+ struct platform_device *pdev;
+ int res, id;
+
+ /* kernfs guarantees string termination, so count + 1 is safe */
+ aggr = kzalloc(sizeof(*aggr) + count + 1, GFP_KERNEL);
+ if (!aggr)
+ return -ENOMEM;
+
+ memcpy(aggr->args, buf, count + 1);
+
+ aggr->lookups = kzalloc(struct_size(aggr->lookups, table, 1),
+ GFP_KERNEL);
+ if (!aggr->lookups) {
+ res = -ENOMEM;
+ goto free_ga;
+ }
+
+ mutex_lock(&gpio_aggregator_lock);
+ id = idr_alloc(&gpio_aggregator_idr, aggr, 0, 0, GFP_KERNEL);
+ mutex_unlock(&gpio_aggregator_lock);
+
+ if (id < 0) {
+ res = id;
+ goto free_table;
+ }
+
+ aggr->lookups->dev_id = kasprintf(GFP_KERNEL, "%s.%d", DRV_NAME, id);
+ if (!aggr->lookups->dev_id) {
+ res = -ENOMEM;
+ goto remove_idr;
+ }
+
+ res = aggr_parse(aggr);
+ if (res)
+ goto free_dev_id;
+
+ gpiod_add_lookup_table(aggr->lookups);
+
+ pdev = platform_device_register_simple(DRV_NAME, id, NULL, 0);
+ if (IS_ERR(pdev)) {
+ res = PTR_ERR(pdev);
+ goto remove_table;
+ }
+
+ aggr->pdev = pdev;
+ return count;
+
+remove_table:
+ gpiod_remove_lookup_table(aggr->lookups);
+free_dev_id:
+ kfree(aggr->lookups->dev_id);
+remove_idr:
+ mutex_lock(&gpio_aggregator_lock);
+ idr_remove(&gpio_aggregator_idr, id);
+ mutex_unlock(&gpio_aggregator_lock);
+free_table:
+ kfree(aggr->lookups);
+free_ga:
+ kfree(aggr);
+ return res;
+}
+
+static DRIVER_ATTR_WO(new_device);
+
+static void gpio_aggregator_free(struct gpio_aggregator *aggr)
+{
+ platform_device_unregister(aggr->pdev);
+ gpiod_remove_lookup_table(aggr->lookups);
+ kfree(aggr->lookups->dev_id);
+ kfree(aggr->lookups);
+ kfree(aggr);
+}
+
+static ssize_t delete_device_store(struct device_driver *driver,
+ const char *buf, size_t count)
+{
+ struct gpio_aggregator *aggr;
+ unsigned int id;
+ int error;
+
+ if (!str_has_prefix(buf, DRV_NAME "."))
+ return -EINVAL;
+
+ error = kstrtouint(buf + strlen(DRV_NAME "."), 10, &id);
+ if (error)
+ return error;
+
+ mutex_lock(&gpio_aggregator_lock);
+ aggr = idr_remove(&gpio_aggregator_idr, id);
+ mutex_unlock(&gpio_aggregator_lock);
+ if (!aggr)
+ return -ENOENT;
+
+ gpio_aggregator_free(aggr);
+ return count;
+}
+static DRIVER_ATTR_WO(delete_device);
+
+static struct attribute *gpio_aggregator_attrs[] = {
+ &driver_attr_new_device.attr,
+ &driver_attr_delete_device.attr,
+ NULL,
+};
+ATTRIBUTE_GROUPS(gpio_aggregator);
+
+static int __exit gpio_aggregator_idr_remove(int id, void *p, void *data)
+{
+ gpio_aggregator_free(p);
+ return 0;
+}
+
+static void __exit gpio_aggregator_remove_all(void)
+{
+ mutex_lock(&gpio_aggregator_lock);
+ idr_for_each(&gpio_aggregator_idr, gpio_aggregator_idr_remove, NULL);
+ idr_destroy(&gpio_aggregator_idr);
+ mutex_unlock(&gpio_aggregator_lock);
+}
+
+
+/*
+ * GPIO Forwarder
+ */
+
+struct gpiochip_fwd {
+ struct gpio_chip chip;
+ struct gpio_desc **descs;
+ union {
+ struct mutex mlock; /* protects tmp[] if can_sleep */
+ spinlock_t slock; /* protects tmp[] if !can_sleep */
+ };
+ unsigned long tmp[]; /* values and descs for multiple ops */
+};
+
+static int gpio_fwd_get_direction(struct gpio_chip *chip, unsigned int offset)
+{
+ struct gpiochip_fwd *fwd = gpiochip_get_data(chip);
+
+ return gpiod_get_direction(fwd->descs[offset]);
+}
+
+static int gpio_fwd_direction_input(struct gpio_chip *chip, unsigned int offset)
+{
+ struct gpiochip_fwd *fwd = gpiochip_get_data(chip);
+
+ return gpiod_direction_input(fwd->descs[offset]);
+}
+
+static int gpio_fwd_direction_output(struct gpio_chip *chip,
+ unsigned int offset, int value)
+{
+ struct gpiochip_fwd *fwd = gpiochip_get_data(chip);
+
+ return gpiod_direction_output(fwd->descs[offset], value);
+}
+
+static int gpio_fwd_get(struct gpio_chip *chip, unsigned int offset)
+{
+ struct gpiochip_fwd *fwd = gpiochip_get_data(chip);
+
+ return gpiod_get_value(fwd->descs[offset]);
+}
+
+static int gpio_fwd_get_multiple(struct gpio_chip *chip, unsigned long *mask,
+ unsigned long *bits)
+{
+ struct gpiochip_fwd *fwd = gpiochip_get_data(chip);
+ unsigned long *values, flags = 0;
+ struct gpio_desc **descs;
+ unsigned int i, j = 0;
+ int error;
+
+ if (chip->can_sleep)
+ mutex_lock(&fwd->mlock);
+ else
+ spin_lock_irqsave(&fwd->slock, flags);
+
+ /* Both values bitmap and desc pointers are stored in tmp[] */
+ values = &fwd->tmp[0];
+ descs = (void *)&fwd->tmp[BITS_TO_LONGS(fwd->chip.ngpio)];
+
+ bitmap_clear(values, 0, fwd->chip.ngpio);
+ for_each_set_bit(i, mask, fwd->chip.ngpio)
+ descs[j++] = fwd->descs[i];
+
+ error = gpiod_get_array_value(j, descs, NULL, values);
+ if (!error) {
+ j = 0;
+ for_each_set_bit(i, mask, fwd->chip.ngpio)
+ __assign_bit(i, bits, test_bit(j++, values));
+ }
+
+ if (chip->can_sleep)
+ mutex_unlock(&fwd->mlock);
+ else
+ spin_unlock_irqrestore(&fwd->slock, flags);
+
+ return error;
+}
+
+static void gpio_fwd_set(struct gpio_chip *chip, unsigned int offset, int value)
+{
+ struct gpiochip_fwd *fwd = gpiochip_get_data(chip);
+
+ gpiod_set_value(fwd->descs[offset], value);
+}
+
+static void gpio_fwd_set_multiple(struct gpio_chip *chip, unsigned long *mask,
+ unsigned long *bits)
+{
+ struct gpiochip_fwd *fwd = gpiochip_get_data(chip);
+ unsigned long *values, flags = 0;
+ struct gpio_desc **descs;
+ unsigned int i, j = 0;
+
+ if (chip->can_sleep)
+ mutex_lock(&fwd->mlock);
+ else
+ spin_lock_irqsave(&fwd->slock, flags);
+
+ /* Both values bitmap and desc pointers are stored in tmp[] */
+ values = &fwd->tmp[0];
+ descs = (void *)&fwd->tmp[BITS_TO_LONGS(fwd->chip.ngpio)];
+
+ for_each_set_bit(i, mask, fwd->chip.ngpio) {
+ __assign_bit(j, values, test_bit(i, bits));
+ descs[j++] = fwd->descs[i];
+ }
+
+ gpiod_set_array_value(j, descs, NULL, values);
+
+ if (chip->can_sleep)
+ mutex_unlock(&fwd->mlock);
+ else
+ spin_unlock_irqrestore(&fwd->slock, flags);
+}
+
+static int gpio_fwd_set_config(struct gpio_chip *chip, unsigned int offset,
+ unsigned long config)
+{
+ struct gpiochip_fwd *fwd = gpiochip_get_data(chip);
+
+ return gpiod_set_config(fwd->descs[offset], config);
+}
+
+/**
+ * gpiochip_fwd_create() - Create a new GPIO forwarder
+ * @dev: Parent device pointer
+ * @ngpios: Number of GPIOs in the forwarder.
+ * @descs: Array containing the GPIO descriptors to forward to.
+ * This array must contain @ngpios entries, and must not be deallocated
+ * before the forwarder has been destroyed again.
+ *
+ * This function creates a new gpiochip, which forwards all GPIO operations to
+ * the passed GPIO descriptors.
+ *
+ * Return: An opaque object pointer, or an ERR_PTR()-encoded negative error
+ * code on failure.
+ */
+static struct gpiochip_fwd *gpiochip_fwd_create(struct device *dev,
+ unsigned int ngpios,
+ struct gpio_desc *descs[])
+{
+ const char *label = dev_name(dev);
+ struct gpiochip_fwd *fwd;
+ struct gpio_chip *chip;
+ unsigned int i;
+ int error;
+
+ fwd = devm_kzalloc(dev, struct_size(fwd, tmp,
+ BITS_TO_LONGS(ngpios) + ngpios), GFP_KERNEL);
+ if (!fwd)
+ return ERR_PTR(-ENOMEM);
+
+ chip = &fwd->chip;
+
+ /*
+ * If any of the GPIO lines are sleeping, then the entire forwarder
+ * will be sleeping.
+ * If any of the chips support .set_config(), then the forwarder will
+ * support setting configs.
+ */
+ for (i = 0; i < ngpios; i++) {
+ struct gpio_chip *parent = gpiod_to_chip(descs[i]);
+
+ dev_dbg(dev, "%u => gpio-%d\n", i, desc_to_gpio(descs[i]));
+
+ if (gpiod_cansleep(descs[i]))
+ chip->can_sleep = true;
+ if (parent && parent->set_config)
+ chip->set_config = gpio_fwd_set_config;
+ }
+
+ chip->label = label;
+ chip->parent = dev;
+ chip->owner = THIS_MODULE;
+ chip->get_direction = gpio_fwd_get_direction;
+ chip->direction_input = gpio_fwd_direction_input;
+ chip->direction_output = gpio_fwd_direction_output;
+ chip->get = gpio_fwd_get;
+ chip->get_multiple = gpio_fwd_get_multiple;
+ chip->set = gpio_fwd_set;
+ chip->set_multiple = gpio_fwd_set_multiple;
+ chip->base = -1;
+ chip->ngpio = ngpios;
+ fwd->descs = descs;
+
+ if (chip->can_sleep)
+ mutex_init(&fwd->mlock);
+ else
+ spin_lock_init(&fwd->slock);
+
+ error = devm_gpiochip_add_data(dev, chip, fwd);
+ if (error)
+ return ERR_PTR(error);
+
+ return fwd;
+}
+
+
+/*
+ * GPIO Aggregator platform device
+ */
+
+static int gpio_aggregator_probe(struct platform_device *pdev)
+{
+ struct device *dev = &pdev->dev;
+ struct gpio_desc **descs;
+ struct gpiochip_fwd *fwd;
+ int i, n;
+
+ n = gpiod_count(dev, NULL);
+ if (n < 0)
+ return n;
+
+ descs = devm_kmalloc_array(dev, n, sizeof(*descs), GFP_KERNEL);
+ if (!descs)
+ return -ENOMEM;
+
+ for (i = 0; i < n; i++) {
+ descs[i] = devm_gpiod_get_index(dev, NULL, i, GPIOD_ASIS);
+ if (IS_ERR(descs[i]))
+ return PTR_ERR(descs[i]);
+ }
+
+ fwd = gpiochip_fwd_create(dev, n, descs);
+ if (IS_ERR(fwd))
+ return PTR_ERR(fwd);
+
+ platform_set_drvdata(pdev, fwd);
+ return 0;
+}
+
+#ifdef CONFIG_OF
+static const struct of_device_id gpio_aggregator_dt_ids[] = {
+ /*
+ * Add GPIO-operated devices controlled from userspace below,
+ * or use "driver_override" in sysfs
+ */
+ {},
+};
+MODULE_DEVICE_TABLE(of, gpio_aggregator_dt_ids);
+#endif
+
+static struct platform_driver gpio_aggregator_driver = {
+ .probe = gpio_aggregator_probe,
+ .driver = {
+ .name = DRV_NAME,
+ .groups = gpio_aggregator_groups,
+ .of_match_table = of_match_ptr(gpio_aggregator_dt_ids),
+ },
+};
+
+static int __init gpio_aggregator_init(void)
+{
+ return platform_driver_register(&gpio_aggregator_driver);
+}
+module_init(gpio_aggregator_init);
+
+static void __exit gpio_aggregator_exit(void)
+{
+ gpio_aggregator_remove_all();
+ platform_driver_unregister(&gpio_aggregator_driver);
+}
+module_exit(gpio_aggregator_exit);
+
+MODULE_AUTHOR("Geert Uytterhoeven <geert+renesas@glider.be>");
+MODULE_DESCRIPTION("GPIO Aggregator");
+MODULE_LICENSE("GPL v2");
diff --git a/drivers/gpio/gpiolib.c b/drivers/gpio/gpiolib.c
index fe5f14a417bdc2a45c6124c28e9493f8eaf73c13..449334732fbfe3b0c2179a114605be0d66ab6912 100644
--- a/drivers/gpio/gpiolib.c
+++ b/drivers/gpio/gpiolib.c
@@ -4622,7 +4622,7 @@ static struct gpio_desc *gpiod_find(struct device *dev, const char *con_id,
if (!table)
return desc;
- for (p = &table->table[0]; p->chip_label; p++) {
+ for (p = &table->table[0]; p->key; p++) {
struct gpio_chip *gc;
/* idx must always match exactly */
@@ -4633,18 +4633,30 @@ static struct gpio_desc *gpiod_find(struct device *dev, const char *con_id,
if (p->con_id && (!con_id || strcmp(p->con_id, con_id)))
continue;
- gc = find_chip_by_name(p->chip_label);
+ if (p->chip_hwnum == U16_MAX) {
+ desc = gpio_name_to_desc(p->key);
+ if (desc) {
+ *flags = p->flags;
+ return desc;
+ }
+
+ dev_warn(dev, "cannot find GPIO line %s, deferring\n",
+ p->key);
+ return ERR_PTR(-EPROBE_DEFER);
+ }
+
+ gc = find_chip_by_name(p->key);
if (!gc) {
/*
* As the lookup table indicates a chip with
- * p->chip_label should exist, assume it may
+ * p->key should exist, assume it may
* still appear later and let the interested
* consumer be probed again or let the Deferred
* Probe infrastructure handle the error.
*/
dev_warn(dev, "cannot find GPIO chip %s, deferring\n",
- p->chip_label);
+ p->key);
return ERR_PTR(-EPROBE_DEFER);
}
@@ -4675,7 +4687,7 @@ static int platform_gpio_count(struct device *dev, const char *con_id)
if (!table)
return -ENOENT;
- for (p = &table->table[0]; p->chip_label; p++) {
+ for (p = &table->table[0]; p->key; p++) {
if ((con_id && p->con_id && !strcmp(con_id, p->con_id)) ||
(!con_id && !p->con_id))
count++;
diff --git a/drivers/i2c/busses/i2c-i801.c b/drivers/i2c/busses/i2c-i801.c
index a9c03f5c34825a95901ca420bc2164e74c0651f1..4f333889489c882a8dabf590118d5caab54129d1 100644
--- a/drivers/i2c/busses/i2c-i801.c
+++ b/drivers/i2c/busses/i2c-i801.c
@@ -1439,9 +1439,9 @@ static int i801_add_mux(struct i801_priv *priv)
return -ENOMEM;
lookup->dev_id = "i2c-mux-gpio";
for (i = 0; i < mux_config->n_gpios; i++) {
- lookup->table[i].chip_label = mux_config->gpio_chip;
- lookup->table[i].chip_hwnum = mux_config->gpios[i];
- lookup->table[i].con_id = "mux";
+ lookup->table[i] = (struct gpiod_lookup)
+ GPIO_LOOKUP(mux_config->gpio_chip,
+ mux_config->gpios[i], "mux", 0);
}
gpiod_add_lookup_table(lookup);
priv->lookup = lookup;
diff --git a/drivers/mfd/sm501.c b/drivers/mfd/sm501.c
index e49787e6bb93e5c84660d9c4a7b3b50370aab4f9..ccd62b963952814e812a3798e6372bcf1dabbd9a 100644
--- a/drivers/mfd/sm501.c
+++ b/drivers/mfd/sm501.c
@@ -1145,22 +1145,14 @@ static int sm501_register_gpio_i2c_instance(struct sm501_devdata *sm,
return -ENOMEM;
lookup->dev_id = "i2c-gpio";
- if (iic->pin_sda < 32)
- lookup->table[0].chip_label = "SM501-LOW";
- else
- lookup->table[0].chip_label = "SM501-HIGH";
- lookup->table[0].chip_hwnum = iic->pin_sda % 32;
- lookup->table[0].con_id = NULL;
- lookup->table[0].idx = 0;
- lookup->table[0].flags = GPIO_ACTIVE_HIGH | GPIO_OPEN_DRAIN;
- if (iic->pin_scl < 32)
- lookup->table[1].chip_label = "SM501-LOW";
- else
- lookup->table[1].chip_label = "SM501-HIGH";
- lookup->table[1].chip_hwnum = iic->pin_scl % 32;
- lookup->table[1].con_id = NULL;
- lookup->table[1].idx = 1;
- lookup->table[1].flags = GPIO_ACTIVE_HIGH | GPIO_OPEN_DRAIN;
+ lookup->table[0] = (struct gpiod_lookup)
+ GPIO_LOOKUP_IDX(iic->pin_sda < 32 ? "SM501-LOW" : "SM501-HIGH",
+ iic->pin_sda % 32, NULL, 0,
+ GPIO_ACTIVE_HIGH | GPIO_OPEN_DRAIN);
+ lookup->table[1] = (struct gpiod_lookup)
+ GPIO_LOOKUP_IDX(iic->pin_scl < 32 ? "SM501-LOW" : "SM501-HIGH",
+ iic->pin_scl % 32, NULL, 1,
+ GPIO_ACTIVE_HIGH | GPIO_OPEN_DRAIN);
gpiod_add_lookup_table(lookup);
icd = dev_get_platdata(&pdev->dev);
diff --git a/include/linux/gpio/machine.h b/include/linux/gpio/machine.h
index 1ebe5be05d5f81fa6cc6452a8b6398748a0118a7..781a053abbb99a1d3c048f3c50879dcec3e366e9 100644
--- a/include/linux/gpio/machine.h
+++ b/include/linux/gpio/machine.h
@@ -20,8 +20,11 @@ enum gpio_lookup_flags {
/**
* struct gpiod_lookup - lookup table
- * @chip_label: name of the chip the GPIO belongs to
- * @chip_hwnum: hardware number (i.e. relative to the chip) of the GPIO
+ * @key: either the name of the chip the GPIO belongs to, or the GPIO line name
+ * Note that GPIO line names are not guaranteed to be globally unique,
+ * so this will use the first match found!
+ * @chip_hwnum: hardware number (i.e. relative to the chip) of the GPIO, or
+ * U16_MAX to indicate that @key is a GPIO line name
* @con_id: name of the GPIO from the device's point of view
* @idx: index of the GPIO in case several GPIOs share the same name
* @flags: bitmask of gpio_lookup_flags GPIO_* values
@@ -30,7 +33,7 @@ enum gpio_lookup_flags {
* functions using platform data.
*/
struct gpiod_lookup {
- const char *chip_label;
+ const char *key;
u16 chip_hwnum;
const char *con_id;
unsigned int idx;
@@ -63,17 +66,17 @@ struct gpiod_hog {
/*
* Simple definition of a single GPIO under a con_id
*/
-#define GPIO_LOOKUP(_chip_label, _chip_hwnum, _con_id, _flags) \
- GPIO_LOOKUP_IDX(_chip_label, _chip_hwnum, _con_id, 0, _flags)
+#define GPIO_LOOKUP(_key, _chip_hwnum, _con_id, _flags) \
+ GPIO_LOOKUP_IDX(_key, _chip_hwnum, _con_id, 0, _flags)
/*
* Use this macro if you need to have several GPIOs under the same con_id.
* Each GPIO needs to use a different index and can be accessed using
* gpiod_get_index()
*/
-#define GPIO_LOOKUP_IDX(_chip_label, _chip_hwnum, _con_id, _idx, _flags) \
+#define GPIO_LOOKUP_IDX(_key, _chip_hwnum, _con_id, _idx, _flags) \
{ \
- .chip_label = _chip_label, \
+ .key = _key, \
.chip_hwnum = _chip_hwnum, \
.con_id = _con_id, \
.idx = _idx, \