Re: [PATCH v2] serial: 8250_of: Add IO space support

[John Garry]

On 27/04/2018 11:36, John Garry wrote:
> Currently the 8250_of driver only supports MEM IO type
> accesses.
>
> Some development boards (Huawei D03, specifically) require
> IO space access for 8250-compatible OF driver support, so
> add it.
>
> The modification is quite simple: just set the port iotype
> and associated flags depending on the device address
> resource type.
>
> Signed-off-by: John Garry <john.garry@xxxxxxxxxx>
> ---

Hi Greg,

Just a gentle reminder of this patch. I didn't see any response.

BTW, I think that this patch should still cleanly apply to your 
tty-testing branch.

Thanks,
John

> Changes v1->v2:
> - rebase to Greg's tty-testing branch
> - use resource_type() helper
>
> diff --git a/drivers/tty/serial/8250/8250_of.c b/drivers/tty/serial/8250/8250_of.c
> index 3de8d6a..bfb37f0 100644
> --- a/drivers/tty/serial/8250/8250_of.c
> +++ b/drivers/tty/serial/8250/8250_of.c
> @@ -92,13 +92,43 @@ static int of_platform_serial_setup(struct platform_device *ofdev,
>  		goto err_unprepare;
>  	}
>
> +	port->flags = UPF_SHARE_IRQ | UPF_BOOT_AUTOCONF | UPF_FIXED_PORT |
> +				  UPF_FIXED_TYPE;
>  	spin_lock_init(&port->lock);
> -	port->mapbase = resource.start;
> -	port->mapsize = resource_size(&resource);
>
> -	/* Check for shifted address mapping */
> -	if (of_property_read_u32(np, "reg-offset", &prop) == 0)
> -		port->mapbase += prop;
> +	if (resource_type(&resource) == IORESOURCE_IO) {
> +		port->iotype = UPIO_PORT;
> +		port->iobase = resource.start;
> +	} else {
> +		port->mapbase = resource.start;
> +		port->mapsize = resource_size(&resource);
> +
> +		/* Check for shifted address mapping */
> +		if (of_property_read_u32(np, "reg-offset", &prop) == 0)
> +			port->mapbase += prop;
> +
> +		port->iotype = UPIO_MEM;
> +		if (of_property_read_u32(np, "reg-io-width", &prop) == 0) {
> +			switch (prop) {
> +			case 1:
> +				port->iotype = UPIO_MEM;
> +				break;
> +			case 2:
> +				port->iotype = UPIO_MEM16;
> +				break;
> +			case 4:
> +				port->iotype = of_device_is_big_endian(np) ?
> +					       UPIO_MEM32BE : UPIO_MEM32;
> +				break;
> +			default:
> +				dev_warn(&ofdev->dev, "unsupported reg-io-width (%d)\n",
> +					 prop);
> +				ret = -EINVAL;
> +				goto err_dispose;
> +			}
> +		}
> +		port->flags |= UPF_IOREMAP;
> +	}
>
>  	/* Check for registers offset within the devices address range */
>  	if (of_property_read_u32(np, "reg-shift", &prop) == 0)
> @@ -114,26 +144,6 @@ static int of_platform_serial_setup(struct platform_device *ofdev,
>  		port->line = ret;
>
>  	port->irq = irq_of_parse_and_map(np, 0);
> -	port->iotype = UPIO_MEM;
> -	if (of_property_read_u32(np, "reg-io-width", &prop) == 0) {
> -		switch (prop) {
> -		case 1:
> -			port->iotype = UPIO_MEM;
> -			break;
> -		case 2:
> -			port->iotype = UPIO_MEM16;
> -			break;
> -		case 4:
> -			port->iotype = of_device_is_big_endian(np) ?
> -				       UPIO_MEM32BE : UPIO_MEM32;
> -			break;
> -		default:
> -			dev_warn(&ofdev->dev, "unsupported reg-io-width (%d)\n",
> -				 prop);
> -			ret = -EINVAL;
> -			goto err_dispose;
> -		}
> -	}
>
>  	info->rst = devm_reset_control_get_optional_shared(&ofdev->dev, NULL);
>  	if (IS_ERR(info->rst)) {
> @@ -147,8 +157,6 @@ static int of_platform_serial_setup(struct platform_device *ofdev,
>
>  	port->type = type;
>  	port->uartclk = clk;
> -	port->flags = UPF_SHARE_IRQ | UPF_BOOT_AUTOCONF | UPF_IOREMAP
> -		| UPF_FIXED_PORT | UPF_FIXED_TYPE;
>  	port->irqflags |= IRQF_SHARED;
>
>  	if (of_property_read_bool(np, "no-loopback-test"))