Hi Sergei,

I noticed one more thing. I'm sorry about commenting this late.

On Tue, Dec 17, 2013 at 11:37:31PM +0400, Sergei Ianovich wrote:

+static int serial_pxa_probe(struct platform_device *pdev)
+{
+	struct uart_8250_port uart = {};
+	struct pxa8250_data *data;
+	struct resource *mmres, *irqres;
+	int ret;
+
+	mmres = platform_get_resource(pdev, IORESOURCE_MEM, 0);
+	irqres = platform_get_resource(pdev, IORESOURCE_IRQ, 0);
+	if (!mmres || !irqres)
+		return -ENODEV;
+
+	data = devm_kzalloc(&pdev->dev, sizeof(*data), GFP_KERNEL);
+	if (!data)
+		return -ENOMEM;
+
+	data->clk = devm_clk_get(&pdev->dev, NULL);
+	if (IS_ERR(data->clk))
+		return PTR_ERR(data->clk);
+
+	ret = clk_prepare(data->clk);
+	if (ret)
+		return ret;
+
+	uart.port.type = PORT_XSCALE;
+	uart.port.iotype = UPIO_MEM32;
+	uart.port.mapbase = mmres->start;
+	uart.port.regshift = 2;
+	uart.port.irq = irqres->start;
+	uart.port.fifosize = 64;
+	uart.port.flags = UPF_IOREMAP | UPF_SKIP_TEST;

Since you set the type PORT_XSCALE, don's you want to use
UPF_FIXED_TYPE flag instead of the UPF_SKIP_TEST here? Otherwise the
type will just get overridden and autoconfig() will be executed.

I'm guessing you also want to prevent things like the irq and the
uartclk from being changed by anybody by using the flag
UPF_FIXED_PORT, right?

+	uart.port.dev = &pdev->dev;
+	uart.port.uartclk = clk_get_rate(data->clk);
+	uart.port.pm = serial_pxa_pm;
+	uart.port.private_data = data;
+	uart.dl_write = serial_pxa_dl_write;
+
+	ret = serial8250_register_8250_port(&uart);
+	if (ret < 0)
+		goto err_clk;
+
+	data->line = ret;
+
+	platform_set_drvdata(pdev, data);
+
+	return 0;
+
+ err_clk:
+	clk_unprepare(data->clk);
+	return ret;
+}

-- 
heikki