static int ams_i2c_probe()

in ams/ams-i2c.c [158:231]

• 51 lines of code
• 9 McCabe index (conditional complexity)

static int ams_i2c_probe(struct i2c_client *client,
			 const struct i2c_device_id *id)
{
	int vmaj, vmin;
	int result;

	/* There can be only one */
	if (unlikely(ams_info.has_device))
		return -ENODEV;

	ams_info.i2c_client = client;

	if (ams_i2c_cmd(AMS_CMD_RESET)) {
		printk(KERN_INFO "ams: Failed to reset the device\n");
		return -ENODEV;
	}

	if (ams_i2c_cmd(AMS_CMD_START)) {
		printk(KERN_INFO "ams: Failed to start the device\n");
		return -ENODEV;
	}

	/* get version/vendor information */
	ams_i2c_write(AMS_CTRL1, 0x02);
	ams_i2c_write(AMS_CTRL2, 0x85);
	ams_i2c_write(AMS_CTRL3, 0x01);

	ams_i2c_cmd(AMS_CMD_READMEM);

	vmaj = ams_i2c_read(AMS_DATA1);
	vmin = ams_i2c_read(AMS_DATA2);
	if (vmaj != 1 || vmin != 52) {
		printk(KERN_INFO "ams: Incorrect device version (%d.%d)\n",
			vmaj, vmin);
		return -ENODEV;
	}

	ams_i2c_cmd(AMS_CMD_VERSION);

	vmaj = ams_i2c_read(AMS_DATA1);
	vmin = ams_i2c_read(AMS_DATA2);
	if (vmaj != 0 || vmin != 1) {
		printk(KERN_INFO "ams: Incorrect firmware version (%d.%d)\n",
			vmaj, vmin);
		return -ENODEV;
	}

	/* Disable interrupts */
	ams_i2c_set_irq(AMS_IRQ_ALL, 0);

	result = ams_sensor_attach();
	if (result < 0)
		return result;

	/* Set default values */
	ams_i2c_write(AMS_SENSLOW, 0x15);
	ams_i2c_write(AMS_SENSHIGH, 0x60);
	ams_i2c_write(AMS_CTRLX, 0x08);
	ams_i2c_write(AMS_CTRLY, 0x0F);
	ams_i2c_write(AMS_CTRLZ, 0x4F);
	ams_i2c_write(AMS_UNKNOWN1, 0x14);

	/* Clear interrupts */
	ams_i2c_clear_irq(AMS_IRQ_ALL);

	ams_info.has_device = 1;

	/* Enable interrupts */
	ams_i2c_set_irq(AMS_IRQ_ALL, 1);

	printk(KERN_INFO "ams: Found I2C based motion sensor\n");

	return 0;
}