[PATCH] serial: tegra: add serial driver

[Stephen Warren]

On 12/17/2012 05:10 AM, Laxman Dewangan wrote:
> Nvidia's Tegra has multiple uart controller which supports:
> - APB dma based controller fifo read/write.
> - End Of Data interrupt in incoming data to know whether end
>   of frame achieve or not.
> - Hw controlled RTS and CTS flow control to reduce SW overhead.
> 
> Add serial driver to use all above feature.

> diff --git a/Documentation/devicetree/bindings/serial/nvidia,serial-tegra.txt b/Documentation/devicetree/bindings/serial/nvidia,serial-tegra.txt

> +Required properties:
> +- compatible : should be "nvidia,tegra20-hsuart", "nvidia,tegra30-hsuart".

I think you want ", or" not just "," there. If both are specified,
"tegra30" should come before "tegra20", so you might want to re-order
that. That said, other bindings say something like
"nvidia,tegra<chip>-hsuart" so avoid having to spell out all the
supported Tegra versions.

> diff --git a/drivers/tty/serial/serial_tegra.c b/drivers/tty/serial/serial_tegra.c

> +struct tegra_uart_chip_data tegra20_uart_chip_data = {
> +	.tx_fifo_full_status		= false,
> +	.allow_txfifo_reset_fifo_mode	= true,
> +	.support_clk_src_div		= false,
> +};
> +
> +struct tegra_uart_chip_data tegra30_uart_chip_data = {
> +	.tx_fifo_full_status		= true,
> +	.allow_txfifo_reset_fifo_mode	= false,
> +	.support_clk_src_div		= true,
> +};

Nit: Perhaps it'd be nice to move those right before
tegra_uart_of_match[] - i.e. right where they're used.

> +static struct tegra_uart_platform_data *tegra_uart_parse_dt(

> +	if (of_get_property(np, "nvidia,enable-modem-interrupt", NULL))
> +		pdata->enable_modem_interrupt = 1;

That should use of_property_read_bool().

> +static int __devinit tegra_uart_probe(struct platform_device *pdev)

> +	if (pdev->dev.of_node) {

That will always be true these days.

I didn't review the body of the UART implementation since I'm not
familiar with drivers/tty/serial nor too much about our UART HW beyond
basic 8250 usage.