Re: Add a "enable" sysfs attribute to the pci devices to allow userspace (Xorg) to enable devices without doing foul direct access

[Arjan van de Ven <arjan@linux.intel.com>]

Jon Smirl wrote:
> On 4/29/06, Arjan van de Ven <arjan@linux.intel.com> wrote:
>> This patch adds an "enable" sysfs attribute to each PCI device. When 
>> read it
>> shows the "enabled-ness" of the device, but you can write a "0" into 
>> it to
>> disable a device, and a "1" to enable it.
> 
> What is the rationale for this?

you snipped that out of the email ;)

> Doing this encourages people to write
> device drivers in user space that probably should be a kernel driver.

not really, there's not a lot you can do. What you CAN do is read roms and stuff like that;
the vbetool and X need that for example

> What are you going to do if two competing apps want to set it to two
> different states?

then you're root and you just shot yourself in the proverbial foot.


> An alternate way to fix this problem is to write a device driver that
> attaches to hardware with PCI class VGA.

and then that sucks too because in linux only 1 driver can bind to a device,
AND you're limited to only vga devices.