On Thu, Sep 18, 2014 at 12:21:20PM +0200, Takashi Iwai wrote:
At Thu, 18 Sep 2014 14:51:26 +0530, Sudip Mukherjee wrote:
On Mon, Sep 15, 2014 at 08:17:52PM +0200, Takashi Iwai wrote:
At Mon, 15 Sep 2014 20:55:54 +0530, Sudip Mukherjee wrote:
On Mon, Sep 15, 2014 at 04:29:48PM +0200, Takashi Iwai wrote:
At Mon, 15 Sep 2014 19:39:41 +0530, Sudip Mukherjee wrote:
<snip> > > > > > > > > diff --git a/sound/pci/ctxfi/ctresource.c b/sound/pci/ctxfi/ctresource.c > > > > index e49d2be..80beecb 100644 > > > > --- a/sound/pci/ctxfi/ctresource.c > > > > +++ b/sound/pci/ctxfi/ctresource.c > > > (snip) > > > > @@ -282,8 +287,9 @@ int rsc_mgr_uninit(struct rsc_mgr *mgr) > > > > case SUM: > > > > break; > > > > default: > > > > - pr_err("ctxfi: Invalid resource type value %d!\n", > > > > - mgr->type); > > > > + dev_err(&(((struct hw *)mgr->hw)->pci->dev), > > > > + "ctxfi: Invalid resource type value %d!\n", > > > > + mgr->type); > > > > > > Did you really conclude that this is the best way? > > > Also, is it good to mix up the usages of both card->dev and &pci->dev? > > > Think again. > > > > > > > i have a doubt regarding this :- > > in the snd_card_new() card->dev is being assigned with &pci->dev , > > then are not they the same ? > > Yes, but how can it be guaranteed in future? We may avoid the > problems in future by keeping the consistency at this moment. It's > one of the good points of keeping code consistent, in addition to: > increased readability / understandability and making the bug easier to > be spotted.
understood the point.
i was trying to get some way of finding out the reference of card->dev from the resource manager , but ... :( i will try again and if i cant find any way i will ask for some hint from you.
Good! A hint is that there is no 100% perfect way to achieve this. It's always compromise, and you'll have to choose which one is better than others. For that, you'll have to evaluate multiple implementations, and it's a really good exercise for coding.
i can find the rsc_mgr from the snd_card or ct_atc but if i want to find the reference to the device from the managers , then either i can go with
- &(((struct hw *)mgr->hw)->pci->dev)
or 2) use pci_get_drvdata with ((struct hw *)mgr->hw)->pci or 3) using container_of with &(((struct hw *)mgr->hw)->pci->dev) to find the pointer to snd_card via card_dev , but it becomes too complicated :(
we can get to all the managers (rsc_mgr, amixer_mgr, src_mgr ...) using atc->rsc_mgrs[] , then there should be some simple way to go the opposite way (reaching atc from the managers) . container_of will not work .. :( or am i missing something??
Adding a new field pointing to card to each struct.
i seriously did not think of that , i was under the impression that a newbie is not supposed to change or add to the designs. anyways, i feel that i understand the code a little better than what i understood at the the time of my first patch. and definitely your "writing-an-alsa-driver" has helped a lot .
thanks sudip
Takashi