static int octeon_i2c_probe()

in busses/i2c-octeon-platdrv.c [135:254]

• 94 lines of code
• 15 McCabe index (conditional complexity)

static int octeon_i2c_probe(struct platform_device *pdev)
{
	struct device_node *node = pdev->dev.of_node;
	int irq, result = 0, hlc_irq = 0;
	struct octeon_i2c *i2c;
	bool cn78xx_style;

	cn78xx_style = of_device_is_compatible(node, "cavium,octeon-7890-twsi");
	if (cn78xx_style) {
		hlc_irq = platform_get_irq(pdev, 0);
		if (hlc_irq < 0)
			return hlc_irq;

		irq = platform_get_irq(pdev, 2);
		if (irq < 0)
			return irq;
	} else {
		/* All adaptors have an irq.  */
		irq = platform_get_irq(pdev, 0);
		if (irq < 0)
			return irq;
	}

	i2c = devm_kzalloc(&pdev->dev, sizeof(*i2c), GFP_KERNEL);
	if (!i2c) {
		result = -ENOMEM;
		goto out;
	}
	i2c->dev = &pdev->dev;

	i2c->roff.sw_twsi = 0x00;
	i2c->roff.twsi_int = 0x10;
	i2c->roff.sw_twsi_ext = 0x18;

	i2c->twsi_base = devm_platform_ioremap_resource(pdev, 0);
	if (IS_ERR(i2c->twsi_base)) {
		result = PTR_ERR(i2c->twsi_base);
		goto out;
	}

	/*
	 * "clock-rate" is a legacy binding, the official binding is
	 * "clock-frequency".  Try the official one first and then
	 * fall back if it doesn't exist.
	 */
	if (of_property_read_u32(node, "clock-frequency", &i2c->twsi_freq) &&
	    of_property_read_u32(node, "clock-rate", &i2c->twsi_freq)) {
		dev_err(i2c->dev,
			"no I2C 'clock-rate' or 'clock-frequency' property\n");
		result = -ENXIO;
		goto out;
	}

	i2c->sys_freq = octeon_get_io_clock_rate();

	init_waitqueue_head(&i2c->queue);

	i2c->irq = irq;

	if (cn78xx_style) {
		i2c->hlc_irq = hlc_irq;

		i2c->int_enable = octeon_i2c_int_enable78;
		i2c->int_disable = octeon_i2c_int_disable78;
		i2c->hlc_int_enable = octeon_i2c_hlc_int_enable78;
		i2c->hlc_int_disable = octeon_i2c_hlc_int_disable78;

		irq_set_status_flags(i2c->irq, IRQ_NOAUTOEN);
		irq_set_status_flags(i2c->hlc_irq, IRQ_NOAUTOEN);

		result = devm_request_irq(&pdev->dev, i2c->hlc_irq,
					  octeon_i2c_hlc_isr78, 0,
					  DRV_NAME, i2c);
		if (result < 0) {
			dev_err(i2c->dev, "failed to attach interrupt\n");
			goto out;
		}
	} else {
		i2c->int_enable = octeon_i2c_int_enable;
		i2c->int_disable = octeon_i2c_int_disable;
		i2c->hlc_int_enable = octeon_i2c_hlc_int_enable;
		i2c->hlc_int_disable = octeon_i2c_int_disable;
	}

	result = devm_request_irq(&pdev->dev, i2c->irq,
				  octeon_i2c_isr, 0, DRV_NAME, i2c);
	if (result < 0) {
		dev_err(i2c->dev, "failed to attach interrupt\n");
		goto out;
	}

	if (OCTEON_IS_MODEL(OCTEON_CN38XX))
		i2c->broken_irq_check = true;

	result = octeon_i2c_init_lowlevel(i2c);
	if (result) {
		dev_err(i2c->dev, "init low level failed\n");
		goto  out;
	}

	octeon_i2c_set_clock(i2c);

	i2c->adap = octeon_i2c_ops;
	i2c->adap.timeout = msecs_to_jiffies(2);
	i2c->adap.retries = 5;
	i2c->adap.bus_recovery_info = &octeon_i2c_recovery_info;
	i2c->adap.dev.parent = &pdev->dev;
	i2c->adap.dev.of_node = node;
	i2c_set_adapdata(&i2c->adap, i2c);
	platform_set_drvdata(pdev, i2c);

	result = i2c_add_adapter(&i2c->adap);
	if (result < 0)
		goto out;
	dev_info(i2c->dev, "probed\n");
	return 0;

out:
	return result;
};