Re: [PATCH v10 4/4] tty: serial: 8250: add DFL bus driver for Altera 16550.

[Andy Shevchenko]

On Mon, Jan 09, 2023 at 04:30:29PM -0800, matthew.gerlach@xxxxxxxxxxxxxxx wrote:
> From: Matthew Gerlach <matthew.gerlach@xxxxxxxxxxxxxxx>
> 
> Add a Device Feature List (DFL) bus driver for the Altera
> 16550 implementation of UART.

...

> +static int dfh_get_u64_param_val(struct dfl_device *dfl_dev, int param_id, u64 *pval)
> +{
> +	size_t psize;
> +	u64 *p;
> +
> +	p = dfh_find_param(dfl_dev, param_id, &psize);
> +	if (IS_ERR(p))
> +		return PTR_ERR(p);

> +	if (psize != sizeof(u64))
> +		return -EINVAL;

If this code stays in the newer versions, make it more robust against changes,
i.e. by using sizeof(*pval).

> +	*pval = *p;
> +
> +	return 0;
> +}

...

> +config SERIAL_8250_DFL
> +	tristate "DFL bus driver for Altera 16550 UART"

5

> +	depends on SERIAL_8250 && FPGA_DFL
> +	help
> +	  This option enables support for a Device Feature List (DFL) bus
> +	  driver for the Altera 16650 UART. One or more Altera 16650 UARTs

6

Which one is correct?

> +	  can be instantiated in a FPGA and then be discovered during
> +	  enumeration of the DFL bus.
> +
> +	  To compile this driver as a module, chose M here: the
> +	  module will be called 8250_dfl.

-- 
With Best Regards,
Andy Shevchenko