static int i2c_pxa_probe()

in busses/i2c-pxa.c [1362:1485]

• 99 lines of code
• 16 McCabe index (conditional complexity)

static int i2c_pxa_probe(struct platform_device *dev)
{
	struct i2c_pxa_platform_data *plat = dev_get_platdata(&dev->dev);
	enum pxa_i2c_types i2c_type;
	struct pxa_i2c *i2c;
	struct resource *res = NULL;
	int ret, irq;

	i2c = devm_kzalloc(&dev->dev, sizeof(struct pxa_i2c), GFP_KERNEL);
	if (!i2c)
		return -ENOMEM;

	/* Default adapter num to device id; i2c_pxa_probe_dt can override. */
	i2c->adap.nr = dev->id;
	i2c->adap.owner   = THIS_MODULE;
	i2c->adap.retries = 5;
	i2c->adap.algo_data = i2c;
	i2c->adap.dev.parent = &dev->dev;
#ifdef CONFIG_OF
	i2c->adap.dev.of_node = dev->dev.of_node;
#endif

	res = platform_get_resource(dev, IORESOURCE_MEM, 0);
	i2c->reg_base = devm_ioremap_resource(&dev->dev, res);
	if (IS_ERR(i2c->reg_base))
		return PTR_ERR(i2c->reg_base);

	irq = platform_get_irq(dev, 0);
	if (irq < 0)
		return irq;

	ret = i2c_pxa_init_recovery(i2c);
	if (ret)
		return ret;

	ret = i2c_pxa_probe_dt(dev, i2c, &i2c_type);
	if (ret > 0)
		ret = i2c_pxa_probe_pdata(dev, i2c, &i2c_type);
	if (ret < 0)
		return ret;

	spin_lock_init(&i2c->lock);
	init_waitqueue_head(&i2c->wait);

	strlcpy(i2c->adap.name, "pxa_i2c-i2c", sizeof(i2c->adap.name));

	i2c->clk = devm_clk_get(&dev->dev, NULL);
	if (IS_ERR(i2c->clk)) {
		dev_err(&dev->dev, "failed to get the clk: %ld\n", PTR_ERR(i2c->clk));
		return PTR_ERR(i2c->clk);
	}

	i2c->reg_ibmr = i2c->reg_base + pxa_reg_layout[i2c_type].ibmr;
	i2c->reg_idbr = i2c->reg_base + pxa_reg_layout[i2c_type].idbr;
	i2c->reg_icr = i2c->reg_base + pxa_reg_layout[i2c_type].icr;
	i2c->reg_isr = i2c->reg_base + pxa_reg_layout[i2c_type].isr;
	i2c->fm_mask = pxa_reg_layout[i2c_type].fm;
	i2c->hs_mask = pxa_reg_layout[i2c_type].hs;

	if (i2c_type != REGS_CE4100)
		i2c->reg_isar = i2c->reg_base + pxa_reg_layout[i2c_type].isar;

	if (i2c_type == REGS_PXA910) {
		i2c->reg_ilcr = i2c->reg_base + pxa_reg_layout[i2c_type].ilcr;
		i2c->reg_iwcr = i2c->reg_base + pxa_reg_layout[i2c_type].iwcr;
	}

	i2c->iobase = res->start;
	i2c->iosize = resource_size(res);

	i2c->irq = irq;

	i2c->slave_addr = I2C_PXA_SLAVE_ADDR;
	i2c->highmode_enter = false;

	if (plat) {
		i2c->adap.class = plat->class;
	}

	if (i2c->high_mode) {
		if (i2c->rate) {
			clk_set_rate(i2c->clk, i2c->rate);
			pr_info("i2c: <%s> set rate to %ld\n",
				i2c->adap.name, clk_get_rate(i2c->clk));
		} else
			pr_warn("i2c: <%s> clock rate not set\n",
				i2c->adap.name);
	}

	clk_prepare_enable(i2c->clk);

	if (i2c->use_pio) {
		i2c->adap.algo = &i2c_pxa_pio_algorithm;
	} else {
		i2c->adap.algo = &i2c_pxa_algorithm;
		ret = devm_request_irq(&dev->dev, irq, i2c_pxa_handler,
				IRQF_SHARED | IRQF_NO_SUSPEND,
				dev_name(&dev->dev), i2c);
		if (ret) {
			dev_err(&dev->dev, "failed to request irq: %d\n", ret);
			goto ereqirq;
		}
	}

	i2c_pxa_reset(i2c);

	ret = i2c_add_numbered_adapter(&i2c->adap);
	if (ret < 0)
		goto ereqirq;

	platform_set_drvdata(dev, i2c);

#ifdef CONFIG_I2C_PXA_SLAVE
	dev_info(&i2c->adap.dev, " PXA I2C adapter, slave address %d\n",
		i2c->slave_addr);
#else
	dev_info(&i2c->adap.dev, " PXA I2C adapter\n");
#endif
	return 0;

ereqirq:
	clk_disable_unprepare(i2c->clk);
	return ret;
}