[PATCH 6.6.y 3/5] gpio: regmap: Allow to allocate regmap-irq device

[William Breathitt Gray <wbg@kernel.org>]

From: Mathieu Dubois-Briand <mathieu.dubois-briand@bootlin.com>

[ Upstream commit 553b75d4bfe9264f631d459fe9996744e0672b0e ]

GPIO controller often have support for IRQ: allow to easily allocate
both gpio-regmap and regmap-irq in one operation.

Reviewed-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Acked-by: Bartosz Golaszewski <bartosz.golaszewski@linaro.org>
Signed-off-by: Mathieu Dubois-Briand <mathieu.dubois-briand@bootlin.com>
Link: https://lore.kernel.org/r/20250824-mdb-max7360-support-v14-5-435cfda2b1ea@bootlin.com
Signed-off-by: Lee Jones <lee@kernel.org>
Stable-dep-of: 2ba5772e530f ("gpio: idio-16: Define fixed direction of the GPIO lines")
Signed-off-by: William Breathitt Gray <wbg@kernel.org>
---
 drivers/gpio/gpio-regmap.c  | 29 +++++++++++++++++++++++++++--
 include/linux/gpio/regmap.h | 11 +++++++++++
 2 files changed, 38 insertions(+), 2 deletions(-)

diff --git a/drivers/gpio/gpio-regmap.c b/drivers/gpio/gpio-regmap.c
index c08c8e528867..c789001241fd 100644
--- a/drivers/gpio/gpio-regmap.c
+++ b/drivers/gpio/gpio-regmap.c
@@ -30,6 +30,11 @@ struct gpio_regmap {
 	unsigned int reg_dir_in_base;
 	unsigned int reg_dir_out_base;
 
+#ifdef CONFIG_REGMAP_IRQ
+	int regmap_irq_line;
+	struct regmap_irq_chip_data *irq_chip_data;
+#endif
+
 	int (*reg_mask_xlate)(struct gpio_regmap *gpio, unsigned int base,
 			      unsigned int offset, unsigned int *reg,
 			      unsigned int *mask);
@@ -203,6 +208,7 @@ EXPORT_SYMBOL_GPL(gpio_regmap_get_drvdata);
  */
 struct gpio_regmap *gpio_regmap_register(const struct gpio_regmap_config *config)
 {
+	struct irq_domain *irq_domain;
 	struct gpio_regmap *gpio;
 	struct gpio_chip *chip;
 	int ret;
@@ -278,8 +284,22 @@ struct gpio_regmap *gpio_regmap_register(const struct gpio_regmap_config *config
 	if (ret < 0)
 		goto err_free_gpio;
 
-	if (config->irq_domain) {
-		ret = gpiochip_irqchip_add_domain(chip, config->irq_domain);
+#ifdef CONFIG_REGMAP_IRQ
+	if (config->regmap_irq_chip) {
+		gpio->regmap_irq_line = config->regmap_irq_line;
+		ret = regmap_add_irq_chip_fwnode(dev_fwnode(config->parent), config->regmap,
+						 config->regmap_irq_line, config->regmap_irq_flags,
+						 0, config->regmap_irq_chip, &gpio->irq_chip_data);
+		if (ret)
+			goto err_free_gpio;
+
+		irq_domain = regmap_irq_get_domain(gpio->irq_chip_data);
+	} else
+#endif
+	irq_domain = config->irq_domain;
+
+	if (irq_domain) {
+		ret = gpiochip_irqchip_add_domain(chip, irq_domain);
 		if (ret)
 			goto err_remove_gpiochip;
 	}
@@ -300,6 +320,11 @@ EXPORT_SYMBOL_GPL(gpio_regmap_register);
  */
 void gpio_regmap_unregister(struct gpio_regmap *gpio)
 {
+#ifdef CONFIG_REGMAP_IRQ
+	if (gpio->irq_chip_data)
+		regmap_del_irq_chip(gpio->regmap_irq_line, gpio->irq_chip_data);
+#endif
+
 	gpiochip_remove(&gpio->gpio_chip);
 	kfree(gpio);
 }
diff --git a/include/linux/gpio/regmap.h b/include/linux/gpio/regmap.h
index a9f7b7faf57b..76f6c73106dc 100644
--- a/include/linux/gpio/regmap.h
+++ b/include/linux/gpio/regmap.h
@@ -40,6 +40,11 @@ struct regmap;
  * @drvdata:		(Optional) Pointer to driver specific data which is
  *			not used by gpio-remap but is provided "as is" to the
  *			driver callback(s).
+ * @regmap_irq_chip:	(Optional) Pointer on an regmap_irq_chip structure. If
+ *			set, a regmap-irq device will be created and the IRQ
+ *			domain will be set accordingly.
+ * @regmap_irq_line	(Optional) The IRQ the device uses to signal interrupts.
+ * @regmap_irq_flags	(Optional) The IRQF_ flags to use for the interrupt.
  *
  * The ->reg_mask_xlate translates a given base address and GPIO offset to
  * register and mask pair. The base address is one of the given register
@@ -78,6 +83,12 @@ struct gpio_regmap_config {
 	int ngpio_per_reg;
 	struct irq_domain *irq_domain;
 
+#ifdef CONFIG_REGMAP_IRQ
+	struct regmap_irq_chip *regmap_irq_chip;
+	int regmap_irq_line;
+	unsigned long regmap_irq_flags;
+#endif
+
 	int (*reg_mask_xlate)(struct gpio_regmap *gpio, unsigned int base,
 			      unsigned int offset, unsigned int *reg,
 			      unsigned int *mask);
-- 
2.51.0