gpio: aggregator: export symbols of the GPIO forwarder library

Export all symbols and create header file for the GPIO forwarder library.
It will be used in the next changes.

Acked-by: Linus Walleij <linus.walleij@linaro.org>
Signed-off-by: Thomas Richard <thomas.richard@bootlin.com>
Link: https://lore.kernel.org/r/20250811-aaeon-up-board-pinctrl-support-v9-6-29f0cbbdfb30@bootlin.com
Signed-off-by: Bartosz Golaszewski <bartosz.golaszewski@linaro.org>

2 files changed, 233 insertions, 6 deletions

diff --git a/drivers/gpio/gpio-aggregator.c b/drivers/gpio/gpio-aggregator.c
index cc54d19f2dd1..c1952b28b7b7 100644
--- a/drivers/gpio/gpio-aggregator.c
+++ b/drivers/gpio/gpio-aggregator.c
@@ -12,6 +12,7 @@
 #include <linux/configfs.h>
 #include <linux/ctype.h>
 #include <linux/delay.h>
+#include <linux/export.h>
 #include <linux/idr.h>
 #include <linux/kernel.h>
 #include <linux/list.h>
@@ -28,6 +29,7 @@
 
 #include <linux/gpio/consumer.h>
 #include <linux/gpio/driver.h>
+#include <linux/gpio/forwarder.h>
 #include <linux/gpio/machine.h>
 
 #include "dev-sync-probe.h"
@@ -475,8 +477,180 @@ static int gpiochip_fwd_setup_delay_line(struct gpiochip_fwd *fwd)
 }
 #endif	/* !CONFIG_OF_GPIO */
 
-static struct gpiochip_fwd *
-devm_gpiochip_fwd_alloc(struct device *dev, unsigned int ngpios)
+/**
+ * gpiochip_fwd_get_gpiochip - Get the GPIO chip for the GPIO forwarder
+ * @fwd: GPIO forwarder
+ *
+ * Returns: The GPIO chip for the GPIO forwarder
+ */
+struct gpio_chip *gpiochip_fwd_get_gpiochip(struct gpiochip_fwd *fwd)
+{
+	return &fwd->chip;
+}
+EXPORT_SYMBOL_NS_GPL(gpiochip_fwd_get_gpiochip, "GPIO_FORWARDER");
+
+/**
+ * gpiochip_fwd_gpio_get_direction - Return the current direction of a GPIO forwarder line
+ * @fwd: GPIO forwarder
+ * @offset: the offset of the line
+ *
+ * Returns: 0 for output, 1 for input, or an error code in case of error.
+ */
+int gpiochip_fwd_gpio_get_direction(struct gpiochip_fwd *fwd, unsigned int offset)
+{
+	struct gpio_chip *gc = gpiochip_fwd_get_gpiochip(fwd);
+
+	return gpio_fwd_get_direction(gc, offset);
+}
+EXPORT_SYMBOL_NS_GPL(gpiochip_fwd_gpio_get_direction, "GPIO_FORWARDER");
+
+/**
+ * gpiochip_fwd_gpio_direction_output - Set a GPIO forwarder line direction to
+ * output
+ * @fwd: GPIO forwarder
+ * @offset: the offset of the line
+ * @value: value to set
+ *
+ * Returns: 0 on success, or negative errno on failure.
+ */
+int gpiochip_fwd_gpio_direction_output(struct gpiochip_fwd *fwd, unsigned int offset,
+				       int value)
+{
+	struct gpio_chip *gc = gpiochip_fwd_get_gpiochip(fwd);
+
+	return gpio_fwd_direction_output(gc, offset, value);
+}
+EXPORT_SYMBOL_NS_GPL(gpiochip_fwd_gpio_direction_output, "GPIO_FORWARDER");
+
+/**
+ * gpiochip_fwd_gpio_direction_input - Set a GPIO forwarder line direction to input
+ * @fwd: GPIO forwarder
+ * @offset: the offset of the line
+ *
+ * Returns: 0 on success, or negative errno on failure.
+ */
+int gpiochip_fwd_gpio_direction_input(struct gpiochip_fwd *fwd, unsigned int offset)
+{
+	struct gpio_chip *gc = gpiochip_fwd_get_gpiochip(fwd);
+
+	return gpio_fwd_direction_input(gc, offset);
+}
+EXPORT_SYMBOL_NS_GPL(gpiochip_fwd_gpio_direction_input, "GPIO_FORWARDER");
+
+/**
+ * gpiochip_fwd_gpio_get - Return a GPIO forwarder line's value
+ * @fwd: GPIO forwarder
+ * @offset: the offset of the line
+ *
+ * Returns: The GPIO's logical value, i.e. taking the ACTIVE_LOW status into
+ * account, or negative errno on failure.
+ */
+int gpiochip_fwd_gpio_get(struct gpiochip_fwd *fwd, unsigned int offset)
+{
+	struct gpio_chip *gc = gpiochip_fwd_get_gpiochip(fwd);
+
+	return gpio_fwd_get(gc, offset);
+}
+EXPORT_SYMBOL_NS_GPL(gpiochip_fwd_gpio_get, "GPIO_FORWARDER");
+
+/**
+ * gpiochip_fwd_gpio_get_multiple - Get values for multiple GPIO forwarder lines
+ * @fwd: GPIO forwarder
+ * @mask: bit mask array; one bit per line; BITS_PER_LONG bits per word defines
+ *        which lines are to be read
+ * @bits: bit value array; one bit per line; BITS_PER_LONG bits per word will
+ *        contains the read values for the lines specified by mask
+ *
+ * Returns: 0 on success, or negative errno on failure.
+ */
+int gpiochip_fwd_gpio_get_multiple(struct gpiochip_fwd *fwd, unsigned long *mask,
+				   unsigned long *bits)
+{
+	struct gpio_chip *gc = gpiochip_fwd_get_gpiochip(fwd);
+
+	return gpio_fwd_get_multiple_locked(gc, mask, bits);
+}
+EXPORT_SYMBOL_NS_GPL(gpiochip_fwd_gpio_get_multiple, "GPIO_FORWARDER");
+
+/**
+ * gpiochip_fwd_gpio_set - Assign value to a GPIO forwarder line.
+ * @fwd: GPIO forwarder
+ * @offset: the offset of the line
+ * @value: value to set
+ *
+ * Returns: 0 on success, or negative errno on failure.
+ */
+int gpiochip_fwd_gpio_set(struct gpiochip_fwd *fwd, unsigned int offset, int value)
+{
+	struct gpio_chip *gc = gpiochip_fwd_get_gpiochip(fwd);
+
+	return gpio_fwd_set(gc, offset, value);
+}
+EXPORT_SYMBOL_NS_GPL(gpiochip_fwd_gpio_set, "GPIO_FORWARDER");
+
+/**
+ * gpiochip_fwd_gpio_set_multiple - Assign values to multiple GPIO forwarder lines
+ * @fwd: GPIO forwarder
+ * @mask: bit mask array; one bit per output; BITS_PER_LONG bits per word
+ *        defines which outputs are to be changed
+ * @bits: bit value array; one bit per output; BITS_PER_LONG bits per word
+ *        defines the values the outputs specified by mask are to be set to
+ *
+ * Returns: 0 on success, or negative errno on failure.
+ */
+int gpiochip_fwd_gpio_set_multiple(struct gpiochip_fwd *fwd, unsigned long *mask,
+				   unsigned long *bits)
+{
+	struct gpio_chip *gc = gpiochip_fwd_get_gpiochip(fwd);
+
+	return gpio_fwd_set_multiple_locked(gc, mask, bits);
+}
+EXPORT_SYMBOL_NS_GPL(gpiochip_fwd_gpio_set_multiple, "GPIO_FORWARDER");
+
+/**
+ * gpiochip_fwd_gpio_set_config - Set @config for a GPIO forwarder line
+ * @fwd: GPIO forwarder
+ * @offset: the offset of the line
+ * @config: Same packed config format as generic pinconf
+ *
+ * Returns: 0 on success, %-ENOTSUPP if the controller doesn't support setting
+ * the configuration.
+ */
+int gpiochip_fwd_gpio_set_config(struct gpiochip_fwd *fwd, unsigned int offset,
+				 unsigned long config)
+{
+	struct gpio_chip *gc = gpiochip_fwd_get_gpiochip(fwd);
+
+	return gpio_fwd_set_config(gc, offset, config);
+}
+EXPORT_SYMBOL_NS_GPL(gpiochip_fwd_gpio_set_config, "GPIO_FORWARDER");
+
+/**
+ * gpiochip_fwd_gpio_to_irq - Return the IRQ corresponding to a GPIO forwarder line
+ * @fwd: GPIO forwarder
+ * @offset: the offset of the line
+ *
+ * Returns: The Linux IRQ corresponding to the passed line, or an error code in
+ * case of error.
+ */
+int gpiochip_fwd_gpio_to_irq(struct gpiochip_fwd *fwd, unsigned int offset)
+{
+	struct gpio_chip *gc = gpiochip_fwd_get_gpiochip(fwd);
+
+	return gpio_fwd_to_irq(gc, offset);
+}
+EXPORT_SYMBOL_NS_GPL(gpiochip_fwd_gpio_to_irq, "GPIO_FORWARDER");
+
+/**
+ * devm_gpiochip_fwd_alloc - Allocate and initialize a new GPIO forwarder
+ * @dev: Parent device pointer
+ * @ngpios: Number of GPIOs in the forwarder
+ *
+ * Returns: An opaque object pointer, or an ERR_PTR()-encoded negative error
+ * code on failure.
+ */
+struct gpiochip_fwd *devm_gpiochip_fwd_alloc(struct device *dev,
+					     unsigned int ngpios)
 {
 	struct gpiochip_fwd *fwd;
 	struct gpio_chip *chip;
@@ -507,10 +681,18 @@ devm_gpiochip_fwd_alloc(struct device *dev, unsigned int ngpios)
 
 	return fwd;
 }
+EXPORT_SYMBOL_NS_GPL(devm_gpiochip_fwd_alloc, "GPIO_FORWARDER");
 
-static int gpiochip_fwd_desc_add(struct gpiochip_fwd *fwd,
-				 struct gpio_desc *desc,
-				 unsigned int offset)
+/**
+ * gpiochip_fwd_desc_add - Add a GPIO desc in the forwarder
+ * @fwd: GPIO forwarder
+ * @desc: GPIO descriptor to register
+ * @offset: offset for the GPIO in the forwarder
+ *
+ * Returns: 0 on success, or negative errno on failure.
+ */
+int gpiochip_fwd_desc_add(struct gpiochip_fwd *fwd, struct gpio_desc *desc,
+			  unsigned int offset)
 {
 	struct gpio_chip *parent = gpiod_to_chip(desc);
 	struct gpio_chip *chip = &fwd->chip;
@@ -537,8 +719,15 @@ static int gpiochip_fwd_desc_add(struct gpiochip_fwd *fwd,
 
 	return 0;
 }
+EXPORT_SYMBOL_NS_GPL(gpiochip_fwd_desc_add, "GPIO_FORWARDER");
 
-static int gpiochip_fwd_register(struct gpiochip_fwd *fwd)
+/**
+ * gpiochip_fwd_register - Register a GPIO forwarder
+ * @fwd: GPIO forwarder
+ *
+ * Returns: 0 on success, or negative errno on failure.
+ */
+int gpiochip_fwd_register(struct gpiochip_fwd *fwd)
 {
 	struct gpio_chip *chip = &fwd->chip;
 
@@ -549,6 +738,7 @@ static int gpiochip_fwd_register(struct gpiochip_fwd *fwd)
 
 	return devm_gpiochip_add_data(chip->parent, chip, fwd);
 }
+EXPORT_SYMBOL_NS_GPL(gpiochip_fwd_register, "GPIO_FORWARDER");
 
 /**
  * gpiochip_fwd_create() - Create a new GPIO forwarder
diff --git a/include/linux/gpio/forwarder.h b/include/linux/gpio/forwarder.h
new file mode 100644
index 000000000000..e21a1b7b1905
--- /dev/null
+++ b/include/linux/gpio/forwarder.h
@@ -0,0 +1,37 @@
+/* SPDX-License-Identifier: GPL-2.0 */
+#ifndef __LINUX_GPIO_FORWARDER_H
+#define __LINUX_GPIO_FORWARDER_H
+
+struct gpio_desc;
+struct gpio_chip;
+struct gpiochip_fwd;
+
+struct gpiochip_fwd *devm_gpiochip_fwd_alloc(struct device *dev,
+					     unsigned int ngpios);
+int gpiochip_fwd_desc_add(struct gpiochip_fwd *fwd,
+			  struct gpio_desc *desc, unsigned int offset);
+int gpiochip_fwd_register(struct gpiochip_fwd *fwd);
+
+struct gpio_chip *gpiochip_fwd_get_gpiochip(struct gpiochip_fwd *fwd);
+
+int gpiochip_fwd_gpio_get_direction(struct gpiochip_fwd *fwd,
+				    unsigned int offset);
+int gpiochip_fwd_gpio_direction_input(struct gpiochip_fwd *fwd,
+				      unsigned int offset);
+int gpiochip_fwd_gpio_direction_output(struct gpiochip_fwd *fwd,
+				       unsigned int offset,
+				       int value);
+int gpiochip_fwd_gpio_get(struct gpiochip_fwd *fwd, unsigned int offset);
+int gpiochip_fwd_gpio_get_multiple(struct gpiochip_fwd *fwd,
+				   unsigned long *mask,
+				   unsigned long *bits);
+int gpiochip_fwd_gpio_set(struct gpiochip_fwd *fwd, unsigned int offset,
+			  int value);
+int gpiochip_fwd_gpio_set_multiple(struct gpiochip_fwd *fwd,
+				   unsigned long *mask,
+				   unsigned long *bits);
+int gpiochip_fwd_gpio_set_config(struct gpiochip_fwd *fwd, unsigned int offset,
+				 unsigned long config);
+int gpiochip_fwd_gpio_to_irq(struct gpiochip_fwd *fwd, unsigned int offset);
+
+#endif