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SubjectRe: Display class
On 12/7/06, James Simmons <> wrote:
> > - I would remove "struct device *dev, void *devdata" of display_device_register()
> > Are they neccesary for other display drivers? I have to pass NULL right now.
> Yes. Passing in a struct device allows you a link between the device and
> the class. If you pass in the device for the parport a link to the parport
> device would exist in you displayX directory. The devdata is used by the
> probe function to get data about the monitor if it is not NULL.
> In the case of most desktop monitors they have EDID blocks. You can
> retrieve them (devdata) and it gets parsed thus you have detail data
> about the monitor. In your case it can be null.
> > - I would add a paramtere ("char *name") to display_device_register() so we
> > set the name when registering. Right now I have to set my name after inited,
> > and this is a Linux module and not a person borning, right? ;)
> The probe function gets this for you. In your case you would have a probe
> method that would just fill in the name of the LCD. For me using the ACPI
> video driver I get the name for my monitor
> LEN 15"XGA 200nit
> Which is the manufacturer - monitor id - ascii block.
> > - I would add a read/writeable attr called "rate" for set/unset the refresh rate
> > of a display.
> I suggest creating a group for your driver. See device.h for
> group_attributes.
> > - I was going to maintain the drivers/auxdisplay/* tree.
> > Are you going to maintain the driver? I think so, just for being sure.
> Yes. I need it for the ACPI video and fbdev layer. Remember its in the
> early stages yet.
> > P.S.
> >
> > When I was working at 2.6.19-rc6-mm2 it worked all fine, but now
> > I have copied it to git7 I'm getting some weird segmentation faults
> > (oops) when at cfag12864bfb_init, at mutex_lock() in
> > display_device_unregister module... I think unrelated (?), but I will
> > look for some mistake I made.
> Did you solve the problem?

I didn't look further, but I will be able to try again in some hours.
Anyway, the problem is probably at cfag12864bfb.c (as it was almost
the only file I modified from -mm2); but I can't tell where the
problem is as I tried just a few times.

Please review cfag12864bfb_init/_exit to check if your code/class is
intended to be used that way, I will focus on the segfaults.


Miguel Ojeda
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