Re: [PATCH] Add Winbond WB528SD Secure Digital (SD) card reader driver

["Németh Márton" <nm127@freemail.hu>]

Hi Greg,

thanks for your response and your questions, I think it will help my
work very much.

Greg KH wrote:
> On Sat, Jan 21, 2012 at 11:52:37AM +0100, Németh Márton wrote:
>> From: Márton Németh <nm127@freemail.hu>
>>
>> This driver version of Winbond WB528SD can detect mechanical card
>> presence only. The information is provided through sysfs.
> 
> How is it provided through sysfs?  Is this done in a standard way?  If
> not, why not?

I used device_create_file()/device_remove_file() and DEVICE_ATTR(), in
that sense it is standard. I'm not sure, however, that you a referring
to this, rather referring to the standard way how other SD card readers
provide the card presence information to the user space, right?
To tell you the truth, I could not find an other PCI card driver which
I can take as an example, I would need some help on this.

> Why is this driver submitted to the staging tree?  What is keeping it
> from going into the "real" portion of the kernel for other card readers?

Interrupt handling, read, write and connecting the driver upwards to the
block subsystem, I guess.

> We need a TODO file for what is needed to get it moved out of staging.

I can create one, no problem.

> Oh, and it needs to do a bit more than just detect a card to be useful,
> right?  How about read/write to it?

Sure. My intention was to get feedback for my work as early as possible.
I reached a state where a minimal level of functionality is available:
the mechanical SD card presence is available for userspace programs.

The read/write access will be a bit more difficult, I guess because I
currently don't have access to the register programming reference of
this device, I can use the trial-and-error method, for example.

	Márton Németh