Re: [RFC PATCH 0/2] serial: 8250_dw: IO space + polling mode support

John Garry
2018-02-26T10:46:19Z

Hi Andy,

>>>> We require it for a development board for our hip06 platform.
>>>
>>> Okay, and this particular platform uses Synopsys IP?
>>
>> As I see this uart is really a virtual 8250, so HW details like apb
>> clocks and the like are hidden, so may not be relevant.
>
> Good to know.
>
>> However I will check with the BMC team to know the specific details.
>
>>>>>> for supporting an 8250-compatible UART with
>>>>>> the following profile/features:
>>>>>> - platform device
>>>>>> - polling mode (i.e. no interrupt support)
>>>>>> - ACPI FW
>>>>>
>>>>> Elaborate this one, please.
>>>>
>>>> So we need to define our own HID here, and cannot use PNP
>>>> compatible
>>>> CID
>>>> (like PNP0501) as we cannot use the 8250 PNP driver.
>>>
>>> Why not? What are the impediments?
>>>
>>
>> To support the host controller for this device, we will create an
>> MFD,
>> i.e. platform device, per slave device.
>
> There is no answer here...
>
>>>> This is related to the Hisi LPC ACPI support, where we would
>>>> create
>>>> an
>>>> MFD (i.e. platform device) for the UART.
>>>
>>> Why you can't do properly in ACPI?
>
> No answer here either.
>
> Sorry, but with this level of communication it's no go for the series.
>

Sorry if my answers did not tell you want you want to know.

My point was that the 8250_pnp driver would be used for a pnp_device,
but we are creating a platform device for this UART slave so would
require a platform device driver, that which 8250_dw.c is. But I will
check on pnp device support.

Much appreciated,
John