Re: [PATCH 2/2] mrst_max3110: fix SPI UART interrupt parameters

[David Cohen <david.a.cohen@linux.intel.com>]

On 10/23/2013 11:23 AM, Felipe Balbi wrote:
> Hi again,
>
> On Wed, Oct 23, 2013 at 01:21:43PM -0500, Felipe Balbi wrote:
>> On Wed, Oct 23, 2013 at 11:10:48AM -0700, David Cohen wrote:
>>>> My idea is always use threaded irq and passing flags into request.
>>>> Like as:
>>>> unsigned long flags = res->flags & IORESOURCE_BITS;
>>>> ...
>>>> request_threaded_irq(max->irq, serial_m3110_irq, IRQF_ONESHOT | flags, "max3110", max);
>>>
>>>
>>> Oh, maybe we were talking about different things afterall :)
>>> The reason this struct plat_max3110 was created is to allow platform
>>> code (located under arch/x86/platform/intel-mid/device_libs/) to define
>>> the irq edge type.
>>> When I saw your comment I though you were referring to struct resource
>>> (which has IORESOURCE_IRQ_* flags). But unlike platform_device,
>>> spi_device has no struct resource * to replace the need of struct
>>> plat_max3110.
>>>
>>> OTOH your suggestion can replace this piece of code:
>>>
>>> @@ -68,6 +69,7 @@ struct uart_max3110 {
>>>          u8 clock;
>>>          u8 parity, word_7bits;
>>>          u16 irq;
>>> +       u16 irq_edge_triggered;
>>
>> max3110 is already edge triggered:
>>
>> 495                 ret = request_irq(max->irq, serial_m3110_irq,
>> 496                                 IRQ_TYPE_EDGE_FALLING, "max3110", max);
>>
>> it would be nice a threaded IRQ instead of using a singlethread
>> workqueue, though.
>
> making it clearer, you only converted to threaded IRQ when
> edge_triggered isn't set, why don't you *always* use threaded IRQs ?

This is a very difficult question to answer, considering the
non-threaded irq is used just to wake up a wq :)
I wish this driver was better maintained.

I'll rework this whole IRQ scheme here.

Br, David Cohen