mcp2210.ko: device tree settting up

dt.dtb

/ {
	mcp2210: mcp2210 {
		compatible = "microchip,mcp2210";
		#address-cells = <1>;
		#size-cells = <0>;
		cs-gpios = <0>;
		
		gpio-controller;

		powerup_chip_settings {
			pin_mode = [01 00 00 00 00 00 00 00 00];
			gpio_value = /bits/ 16 <0x0000>;
			gpio_direction = /bits/ 16 <0x0040>; /* 0x0040 = 0000 0100 0000 */
			other_settings = /bits/ 8 <0x01>;
			nvram_access_control = /bits/ 8 <0>;
			password = [00 00 00 00 00 00 00 00];
		};

		chip_settings {
			pin_mode = [01 00 00 00 00 00 00 00 00];
			gpio_value = /bits/ 16 <0x0000>;
			gpio_direction = /bits/ 16 <0x0040>; /* 0x0040 = 0000 0100 0000 */
			other_settings = /bits/ 8 <0x01>;
			nvram_access_control = /bits/ 8 <0>;
			password = [00 00 00 00 00 00 00 00];
		};

		powerup_spi_settings {
			/* Powerup spi settings */
			bitrate	= <12000000>;
			idle_cs	= /bits/ 16 <0x01ff>;
			active_cs = /bits/ 16 <0x0000>;
			cs_to_data_delay = /bits/ 16 <10>;
			last_byte_to_cs_delay = /bits/ 16 <10>;
			delay_between_bytes	= /bits/ 16 <10>;
			bytes_per_trans	= /bits/ 16 <5>;
			mode = /bits/ 8 <3>;
		};

		spi_settings {
			/* Powerup spi settings */
			bitrate	= <12000000>;
			idle_cs	= /bits/ 16 <0x01ff>;
			active_cs = /bits/ 16 <0x0000>;
			cs_to_data_delay = /bits/ 16 <10>;
			last_byte_to_cs_delay = /bits/ 16 <10>;
			delay_between_bytes	= /bits/ 16 <10>;
			bytes_per_trans	= /bits/ 16 <32>;
			mode = /bits/ 8 <3>;
		};

		usb_settings {
			/* usb key parameters */
			vid	= /bits/ 16 <0x04d8>; /* Microchip */
			pid	= /bits/ 16 <0x00de>; /* USB device ID */
			chip_power_option = /bits/ 8 <0x80>;
			requested_power   = /bits/ 8 <0x32>; /* 100mA */
		};

		pin_configuration {
			/* board specific configurations */
			poll_gpio_usecs	= <0>;
			stale_gpio_usecs = <0>;
			poll_intr_usecs	= <0>;
			stale_intr_usecs = <0>;
			3wire_capable = /bits/ 8 <0>;
			3wire_tx_enable_active_high = /bits/ 8 <0>;
			3wire_tx_enable_pin	= /bits/ 8 <0>;
			strings_size = <0>;

			pin@0 {
				pin = /bits/ 8 <0>;
				mode = /bits/ 8 <1>;
				pin_name = "HI-3200";
				modalias = "nrf24";
				spi_prop {
					spi,max_speed_hz = <8000000>;
					spi,min_speed_hz = <8000000>;
					spi,mode = /bits/ 8 <3>;
					spi,bits_per_word = /bits/ 8 <8>;
					spi,cs_to_data_delay = /bits/ 16 <10>;
					spi,last_byte_to_cs_delay = /bits/ 16 <10>;
					spi,delay_between_bytes = /bits/ 16 <10>;
					spi,delay_between_xfers = /bits/ 16 <10>;
				};
			};
			pin@1 {
				pin = /bits/ 8 <1>;
				mode = /bits/ 8 <0>;
				pin_name ="gpio%d";
			};
			pin@2 {
				pin = /bits/ 8 <2>;
				mode = /bits/ 8 <0>;
				pin_name ="gpio%d";
			};
			pin@3 {
				pin = /bits/ 8 <3>;
				mode = /bits/ 8 <0>;
				pin_name ="gpio%d";
			};
			pin@4 {
				pin = /bits/ 8 <4>;
				mode = /bits/ 8 <0>;
				pin_name ="gpio%d";
			};
			pin@5 {
				pin = /bits/ 8 <5>;
				mode = /bits/ 8 <0>;
				pin_name ="gpio%d";
			};
			pin@6 {
				pin = /bits/ 8 <6>;
				mode = /bits/ 8 <0>;
				has_irq = /bits/ 8 <0>;
				irq = /bits/ 8 <0>;
				pin_name ="gpio%d";
			};
			pin@7 {
				pin = /bits/ 8 <7>;
				mode = /bits/ 8 <0>;
				pin_name ="gpio%d";
			};
			pin@8 {
				pin = /bits/ 8 <8>;
				mode = /bits/ 8 <0>;
				pin_name ="gpio%d";
			};
		};
	};
};

&mcp2210 {
        nrf24@0 {
                compatible = "nrf24";
                #address-cells = <1>;
                #size-cells = <0>;
                reg = <0>;
                spi-max-frequency = <8000000>;
                gpio-irq = <&mcp2210 2 0>;
                gpio-ce  = <&mcp2210 1 0>;
		gpio-led = <&mcp2210 3 0>;
        };
};

Makefile

obj-m := nrf24.o

all:
	$(MAKE) -C $(KERNEL_SRC) M=$(PWD)

clean:
	$(MAKE) -C $(KERNEL_SRC) M=$(PWD) clean

nrf24.c

#include <linux/kernel.h>
#include <linux/module.h>
#include <linux/spi/spi.h>

static int rf_probe(struct spi_device *spi)
{
	struct device_node *np = spi->dev.of_node;

	BUG_ON(!spi);
	if (!np) {
		dev_err(&spi->dev, "No device tree configuration found");
		return -ENODEV;
	}
	
	dev_info(&spi->dev, "probed successfully");
	return 0;
}

static int rf_remove(struct spi_device *spi)
{
	return 0;
}

static const struct of_device_id rf_of_ids[] = {
        { .compatible = "nrf24" },
        {},
};

static struct spi_driver rf_driver = {
        .driver = {
                .name  = "nrf24",
                .owner = THIS_MODULE,
                .of_match_table = rf_of_ids,
        },
        .probe  = rf_probe,
        .remove = rf_remove,
};
module_spi_driver(rf_driver);
MODULE_LICENSE("GPL");