drivers: i2c: npcx: add support for NPCKn variant

In NPCXn variant, the I2C peripheral hardware uses FIFO for data
transfer, while in NPCKn variant, it uses DMA.
This change separates the FIFO-specific code from the common controller
logic and adds support for DMA mode.

Signed-off-by: Mulin Chao <[email protected]>
Signed-off-by: Jun Lin <[email protected]>

Author: ChiHuaL

drivers/i2c/CMakeLists.txt

@@ -48,8 +48,18 @@ zephyr_library_sources_ifdef(CONFIG_I2C_MCHP_MSS	i2c_mchp_mss.c)
 zephyr_library_sources_ifdef(CONFIG_I2C_MCUX		i2c_mcux.c)
 zephyr_library_sources_ifdef(CONFIG_I2C_MCUX_FLEXCOMM	i2c_mcux_flexcomm.c)
 zephyr_library_sources_ifdef(CONFIG_I2C_NIOS2		i2c_nios2.c)
-zephyr_library_sources_ifdef(CONFIG_I2C_NPCX		i2c_npcx_controller.c)
-zephyr_library_sources_ifdef(CONFIG_I2C_NPCX		i2c_npcx_port.c)
+
+zephyr_library_sources_ifdef(CONFIG_I2C_NPCX_DMA_DRIVEN
+	i2c_npcx_controller.c
+	i2c_npcx_controller_dma.c
+	i2c_npcx_port.c
+	)
+zephyr_library_sources_ifdef(CONFIG_I2C_NPCX_FIFO_DRIVEN
+	i2c_npcx_controller.c
+	i2c_npcx_controller_fifo.c
+	i2c_npcx_port.c
+	)
+
 zephyr_library_sources_ifdef(CONFIG_I2C_NRFX_TWIS	i2c_nrfx_twis.c)
 zephyr_library_sources_ifdef(CONFIG_I2C_NUMAKER		i2c_numaker.c)
 zephyr_library_sources_ifdef(CONFIG_I2C_NXP_II2C	i2c_nxp_ii2c.c)

drivers/i2c/Kconfig.npcx

@@ -20,3 +20,21 @@ config I2C_NPCX_PORT_INIT_PRIORITY
 	help
 	  Initialization priority for the I2C port on an NPCX device, must be
 	  set to a lower priority than the controller one (I2C_INIT_PRIORITY).
+
+config I2C_NPCX_FIFO_DRIVEN
+	bool
+	default y
+	depends on $(dt_compat_any_has_prop,$(DT_COMPAT_NUVOTON_NPCX_I2C_CTRL),dma-driven,False)
+	depends on I2C_NPCX
+	help
+	  For I2C peripherals that support FIFO mode, data transfers shall be performed
+	  using FIFO‑driven transactions.
+
+config I2C_NPCX_DMA_DRIVEN
+	bool
+	default y
+	depends on $(dt_compat_any_has_prop,$(DT_COMPAT_NUVOTON_NPCX_I2C_CTRL),dma-driven,True)
+	depends on I2C_NPCX
+	help
+	  For I2C peripherals that support DMA mode, data transfers shall be performed
+	  using DMA‑driven transactions.