lkml.org 
[lkml]   [2003]   [Feb]   [9]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
 
Messages in this thread
/
Date
From
SubjectRe: [alsa, pnp] more on opl3sa2 (fwd)
On Wed, 5 Feb 2003, Adam Belay wrote:

> On Mon, Feb 03, 2003 at 03:15:59PM +0100, Jaroslav Kysela wrote:
> > On Thu, 30 Jan 2003, Adam Belay wrote:
> >
> > > Hi Jaroslav,
> > >
> > > How does this sound...
> > >
> > > What if we make pnp card services match against all pnp cards and allow more
> > > than one card driver to use the same card. This can be accomplished if we detach
> > > the card portion from the driver model and use driver_attach. If you feel it is
> >
> > The question is probably another. I know that your solution will work, but
> > do we need such hack against the driver model in our code? If you work
> > with cards as buses, it allows us the same model as PCI code.
> >
> > > necessary, we could also add an optional card id to the pnp_device_id structure.
> > > As for the pnpbios, I disagree with putting it under one card. If the pnpbios
> > > contains two opl3sa2 sound cards then only one will be matched and therefore it
> >
> > It's not true. The driver model calls probe for all instances.
> >
> > > is a bad idea to represent the pnpbios as a card. When ACPI is introduced, both
> >
> > Note that if we make card as bus, then this problem will disapear.
> > The enumeration will be simple: devices on the one bus. And it's strong
> > advantage over current implementation when bus == protocol.
> >
> > What do you think about this model:
> >
> > bus (PnP BIOS) -> devices
> > bus (ACPI) -> devices
> > bus (ISA PnP) -> bus (cards) -> devices
> >
>
> I think this model has potential but before we go that direction I'd like to hear
> your reactions on another more simplistic model. I'll express it with a
> hypothetical code example. This model completely drops individual card matching
> and is compatible with both card users and non-card users.
>
>
> static struct pnp_device_id snd_als100_pnpids[] = {
> /* ALS100 - PRO16PNP */
> {.card_id = "ALS0001" .id = "@@@0001", .driver_data = ALS100_AUDIO},
> {.card_id = "ALS0001" .id = "@X@0001", .driver_data = ALS100_MPU},
> {.card_id = "ALS0001" .id = "@H@0001", .driver_data = ALS100_OPL},
> /* ALS110 - MF1000 - Digimate 3D Sound */
> {.card_id = "ALS0110" .id = "@@@1001", .driver_data = ALS100_AUDIO},
> {.card_id = "ALS0001" .id = "@X@1001", .driver_data = ALS100_MPU},
> {.card_id = "ALS0001" .id = "@H@1001", .driver_data = ALS100_OPL},
> ---> snip
> };
>
>
> static int __init snd_card_als100_probe(struct pnp_dev * dev, struct pnp_device_id * id)
> {
> ---> snip
> snd_card_t *card;
> ---> snip
> card = snd_card_find(dev->card); /* this function searches for previously
> registered sound cards and binds this
> device to it if it finds that it was a
> member of the same pnp_card */
> if (!card) {
> if ((card = snd_card_new(index[dev], id[dev], THIS_MODULE,
> sizeof(struct snd_card_als100))) == NULL)
> return -ENOMEM;
> }
> switch (id->driver_data) {
> case ALS100_AUDIO:
> ---> snip
> case ALS100_MPU:
> ---> snip
> case ALS100_OPL:
> ---> snip
> etc . . .
>
>
> I'm interested in your opinions on this approach.

I'm sure that this model will work, but it's a bit complicated to
allocate devices in this way. I'd prefer to probe / allocate devices in
one shot. Anyway, it's a step forward. I'm thinking about this scenario:

Pass id list "match all" (or we can have a match callback in the
pnp_driver structure) and find/allocate multiple devices manually in
probe.

Jaroslav

-----
Jaroslav Kysela <perex@suse.cz>
Linux Kernel Sound Maintainer
ALSA Project, SuSE Labs


-
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@vger.kernel.org
More majordomo info at http://vger.kernel.org/majordomo-info.html
Please read the FAQ at http://www.tux.org/lkml/

\
 
 \ /
  Last update: 2005-03-22 13:33    [W:0.060 / U:3.968 seconds]
©2003-2020 Jasper Spaans|hosted at Digital Ocean and TransIP|Read the blog|Advertise on this site