From cbbe33996e1f141401e417270b44e5752ac21b8c Mon Sep 17 00:00:00 2001
From: Mahesh Mahadevan <mahesh.mahadevan@nxp.com>
Date: Mon, 25 Mar 2024 12:26:32 -0500
Subject: [PATCH] drivers: i2c: Use the NXP Flexcomm driver for interrupt
 handling

The Low Power Flexcomm driver manages the interrupt handling
and provides an API to register interrupt callbacks.
Register the NXP LPI2C interrupt handler.

Signed-off-by: Mahesh Mahadevan <mahesh.mahadevan@nxp.com>
---
 drivers/i2c/i2c_mcux_lpi2c.c | 28 +++++++++++++++++++++++++---
 1 file changed, 25 insertions(+), 3 deletions(-)

diff --git a/drivers/i2c/i2c_mcux_lpi2c.c b/drivers/i2c/i2c_mcux_lpi2c.c
index b87ee94823..0bb7e2d402 100644
--- a/drivers/i2c/i2c_mcux_lpi2c.c
+++ b/drivers/i2c/i2c_mcux_lpi2c.c
@@ -14,6 +14,9 @@
 #include <zephyr/kernel.h>
 #include <zephyr/irq.h>
 #include <fsl_lpi2c.h>
+#if CONFIG_NXP_LP_FLEXCOMM
+#include <zephyr/drivers/mfd/nxp_lp_flexcomm.h>
+#endif
 
 #include <zephyr/drivers/pinctrl.h>
 
@@ -39,6 +42,9 @@ LOG_MODULE_REGISTER(mcux_lpi2c);
 
 struct mcux_lpi2c_config {
 	DEVICE_MMIO_NAMED_ROM(reg_base);
+#ifdef CONFIG_NXP_LP_FLEXCOMM
+	const struct device *parent_dev;
+#endif
 	const struct device *clock_dev;
 	clock_control_subsys_t clock_subsys;
 	void (*irq_config_func)(const struct device *dev);
@@ -530,8 +536,16 @@ static int mcux_lpi2c_init(const struct device *dev)
 	if (error) {
 		return error;
 	}
-
+#if CONFIG_NXP_LP_FLEXCOMM
+	/* When using LP Flexcomm driver, register the interrupt handler
+	 * so we receive notification from the LP Flexcomm interrupt handler.
+	 */
+	nxp_lp_flexcomm_setirqhandler(config->parent_dev, dev,
+				      LP_FLEXCOMM_PERIPH_LPI2C, mcux_lpi2c_isr);
+#else
+	/* Interrupt is managed by this driver */
 	config->irq_config_func(dev);
+#endif
 
 	return 0;
 }
@@ -560,7 +574,7 @@ static const struct i2c_driver_api mcux_lpi2c_driver_api = {
 	do {								\
 		IRQ_CONNECT(DT_INST_IRQN(n),				\
 			DT_INST_IRQ(n, priority),			\
-			mcux_lpi2c_isr, 				\
+			mcux_lpi2c_isr,					\
 			DEVICE_DT_INST_GET(n), 0);			\
 		irq_enable(DT_INST_IRQN(n));				\
 	} while (false)
@@ -569,13 +583,21 @@ static const struct i2c_driver_api mcux_lpi2c_driver_api = {
 	IF_ENABLED(DT_INST_IRQ_HAS_IDX(n, 0),				\
 		(I2C_MCUX_LPI2C_MODULE_IRQ_CONNECT(n)))
 
+#ifdef CONFIG_NXP_LP_FLEXCOMM
+#define PARENT_DEV(n)							\
+	.parent_dev = DEVICE_DT_GET(DT_INST_PARENT(n)),
+#else
+#define PARENT_DEV(n)
+#endif /* CONFIG_NXP_LP_FLEXCOMM */
+
 #define I2C_MCUX_LPI2C_INIT(n)						\
 	PINCTRL_DT_INST_DEFINE(n);					\
 									\
 	static void mcux_lpi2c_config_func_##n(const struct device *dev); \
 									\
 	static const struct mcux_lpi2c_config mcux_lpi2c_config_##n = {	\
-		DEVICE_MMIO_NAMED_ROM_INIT(reg_base, DT_DRV_INST(n)), \
+		DEVICE_MMIO_NAMED_ROM_INIT(reg_base, DT_DRV_INST(n)),	\
+		PARENT_DEV(n)						\
 		.clock_dev = DEVICE_DT_GET(DT_INST_CLOCKS_CTLR(n)),	\
 		.clock_subsys =						\
 			(clock_control_subsys_t)DT_INST_CLOCKS_CELL(n, name),\