boards: lpcxpresso54114: Enable i2c instance 4

Enables i2c instance 4 on the lpcxpresso54114 board. Configures pinmuxes
and clocks, and updates board documentation accordingly.

Signed-off-by: Maureen Helm <maureen.helm@nxp.com>

boards/arm/lpcxpresso54114/Kconfig.defconfig

@@ -33,6 +33,10 @@ config GPIO_MCUX_LPC_PORT1
 
 endif # GPIO_MCUX_LPC
 
+config I2C_4
+	default y
+	depends on I2C
+
 config SPI_5
 	default y
 	depends on SPI

boards/arm/lpcxpresso54114/doc/index.rst

@@ -62,6 +62,8 @@ features:
 +-----------+------------+-------------------------------------+
 | GPIO      | on-chip    | gpio                                |
 +-----------+------------+-------------------------------------+
+| I2C       | on-chip    | i2c                                 |
++-----------+------------+-------------------------------------+
 | SPI       | on-chip    | spi                                 |
 +-----------+------------+-------------------------------------+
 | USART     | on-chip    | serial port-polling                 |
@@ -93,6 +95,10 @@ functionality of a pin.
 +---------+-----------------+----------------------------+
 | PIO0_20 | SPI             | SPI MOSI                   |
 +---------+-----------------+----------------------------+
+| PIO0_25 | I2C             | I2C SCL                    |
++---------+-----------------+----------------------------+
+| PIO0_26 | I2C             | I2C SDA                    |
++---------+-----------------+----------------------------+
 | PIO0_29 | GPIO            | RED LED                    |
 +---------+-----------------+----------------------------+
 | PIO1_1  | SPI             | SPI SSEL2                  |

boards/arm/lpcxpresso54114/lpcxpresso54114.dtsi

@@ -31,4 +31,6 @@
 	};
 };
 
+arduino_i2c: &i2c4 {};
+
 arduino_spi: &spi5 {};

boards/arm/lpcxpresso54114/lpcxpresso54114_m4.dts

@@ -68,6 +68,10 @@
 	status = "okay";
 };
 
+&i2c4 {
+	status = "okay";
+};
+
 &spi5 {
 	status = "okay";
 };

boards/arm/lpcxpresso54114/lpcxpresso54114_m4.yaml

@@ -15,6 +15,8 @@ toolchain:
   - gnuarmemb
   - xtools
 supported:
+  - arduino_i2c
   - arduino_spi
   - gpio
+  - i2c
   - spi

boards/arm/lpcxpresso54114/pinmux.c

@@ -107,6 +107,26 @@ static int lpcxpresso_54114_pinmux_init(struct device *dev)
 	pinmux_pin_set(port1, 10, port1_pin10_config);
 #endif
 
+#ifdef CONFIG_I2C_4
+	/* PORT0 PIN25 is configured as FC4_RTS_SCL_SSEL1 */
+	pinmux_pin_set(port0, 25, IOCON_PIO_FUNC1 |
+				  IOCON_PIO_I2CSLEW_I2C |
+				  IOCON_PIO_INV_DI |
+				  IOCON_PIO_DIGITAL_EN |
+				  IOCON_PIO_INPFILT_OFF |
+				  IOCON_PIO_I2CDRIVE_LOW |
+				  IOCON_PIO_I2CFILTER_EN);
+
+	/* PORT0 PIN26 is configured as FC4_CTS_SDA_SSEL0 */
+	pinmux_pin_set(port0, 26, IOCON_PIO_FUNC1 |
+				  IOCON_PIO_I2CSLEW_I2C |
+				  IOCON_PIO_INV_DI |
+				  IOCON_PIO_DIGITAL_EN |
+				  IOCON_PIO_INPFILT_OFF |
+				  IOCON_PIO_I2CDRIVE_LOW |
+				  IOCON_PIO_I2CFILTER_EN);
+#endif /* CONFIG_I2C_4 */
+
 #ifdef CONFIG_SPI_5
 	/* PORT0 PIN18 is configured as FC5_TXD_SCL_MISO */
 	pinmux_pin_set(port0, 18, IOCON_PIO_FUNC1 |

soc/arm/nxp_lpc/lpc54xxx/soc.c

@@ -66,6 +66,14 @@ static ALWAYS_INLINE void clock_init(void)
 	/* Attach 12 MHz clock to FLEXCOMM0 */
 	CLOCK_AttachClk(kFRO12M_to_FLEXCOMM0);
 
+#ifdef CONFIG_I2C_4
+	/* attach 12 MHz clock to FLEXCOMM4 */
+	CLOCK_AttachClk(kFRO12M_to_FLEXCOMM4);
+
+	/* reset FLEXCOMM for I2C */
+	RESET_PeripheralReset(kFC4_RST_SHIFT_RSTn);
+#endif /* CONFIG_I2C_4 */
+
 #ifdef CONFIG_SPI_5
 	/* Attach 12 MHz clock to FLEXCOMM5 */
 	CLOCK_AttachClk(kFRO12M_to_FLEXCOMM5);

soc/arm/nxp_lpc/lpc54xxx/soc.h

@@ -30,6 +30,9 @@
 #define IOCON_PIO_FUNC2		0x02u
 #define IOCON_PIO_FUNC3		0x03u
 #define IOCON_PIO_FUNC4		0x04u
+#define IOCON_PIO_I2CDRIVE_LOW	0x00u
+#define IOCON_PIO_I2CFILTER_EN	0x00u
+#define IOCON_PIO_I2CSLEW_I2C	0x00u
 #define IOCON_PIO_INPFILT_OFF	0x0100u
 #define IOCON_PIO_INV_DI	0x00u
 #define IOCON_PIO_MODE_INACT	0x00u