Re: [PATCH v4] portman2x4 - use new parport device model

[Takashi Iwai]

On Tue, 16 Feb 2016 18:33:31 +0100,
Sudip Mukherjee wrote:
> 
> Modify portman driver to use the new parallel port device model.
> The advantage of using the device model is that the device gets binded
> to the hardware, we get the feature of hotplug, we can bind/unbind
> the driver at runtime.
> The changes are in the way the driver gets registered with the
> parallel port subsystem and the temporary device to probe portman card
> is removed and portman_probe() is used in the probe callback.
> 
> Signed-off-by: Sudip Mukherjee <sudip@xxxxxxxxxxxxxxx>
> ---
> 
> v4: temporary device to probe is removed.
> v3: changed commit message
> v2:
>  1. pardev_cb is initialized while declaring, thus removing the use of
> memset.
>  2. used pdev->id.
>  3. v1 did not have the parport probe callback, but
> we will need the probe callback for binding as the name of the driver
> and the name of the device is different.
>  4. in v1 I missed modifying snd_portman_probe_port().
> 
>  sound/drivers/portman2x4.c | 79 +++++++++++++++++++++++-----------------------
>  1 file changed, 40 insertions(+), 39 deletions(-)
> 
> diff --git a/sound/drivers/portman2x4.c b/sound/drivers/portman2x4.c
> index 464385a..0741a3b 100644
> --- a/sound/drivers/portman2x4.c
> +++ b/sound/drivers/portman2x4.c
> @@ -648,30 +648,6 @@ static void snd_portman_interrupt(void *userdata)
>  	spin_unlock(&pm->reg_lock);
>  }
>  
> -static int snd_portman_probe_port(struct parport *p)
> -{
> -	struct pardevice *pardev;
> -	int res;
> -
> -	pardev = parport_register_device(p, DRIVER_NAME,
> -					 NULL, NULL, NULL,
> -					 0, NULL);
> -	if (!pardev)
> -		return -EIO;
> -	
> -	if (parport_claim(pardev)) {
> -		parport_unregister_device(pardev);
> -		return -EIO;
> -	}
> -
> -	res = portman_probe(p);
> -
> -	parport_release(pardev);
> -	parport_unregister_device(pardev);
> -
> -	return res ? -EIO : 0;
> -}
> -
>  static void snd_portman_attach(struct parport *p)
>  {
>  	struct platform_device *device;
> @@ -705,10 +681,20 @@ static void snd_portman_detach(struct parport *p)
>  	/* nothing to do here */
>  }
>  
> +static int snd_portman_dev_probe(struct pardevice *pardev)
> +{
> +	if (strcmp(pardev->name, DRIVER_NAME))
> +		return -ENODEV;
> +
> +	return 0;
> +}
> +
>  static struct parport_driver portman_parport_driver = {
> -	.name   = "portman2x4",
> -	.attach = snd_portman_attach,
> -	.detach = snd_portman_detach
> +	.name		= "portman2x4",
> +	.probe		= snd_portman_dev_probe,
> +	.match_port	= snd_portman_attach,
> +	.detach		= snd_portman_detach,
> +	.devmodel	= true,
>  };
>  
>  /*********************************************************************
> @@ -736,6 +722,12 @@ static int snd_portman_probe(struct platform_device *pdev)
>  	struct snd_card *card = NULL;
>  	struct portman *pm = NULL;
>  	int err;
> +	struct pardev_cb portman_cb = {
> +		.preempt = NULL,
> +		.wakeup = NULL,
> +		.irq_func = snd_portman_interrupt,	/* ISR */
> +		.flags = PARPORT_DEV_EXCL,		/* flags */
> +	};
>  
>  	p = platform_get_drvdata(pdev);
>  	platform_set_drvdata(pdev, NULL);
> @@ -745,9 +737,6 @@ static int snd_portman_probe(struct platform_device *pdev)
>  	if (!enable[dev]) 
>  		return -ENOENT;
>  
> -	if ((err = snd_portman_probe_port(p)) < 0)
> -		return err;
> -
>  	err = snd_card_new(&pdev->dev, index[dev], id[dev], THIS_MODULE,
>  			   0, &card);
>  	if (err < 0) {
> @@ -759,23 +748,33 @@ static int snd_portman_probe(struct platform_device *pdev)
>  	sprintf(card->longname,  "%s at 0x%lx, irq %i", 
>  		card->shortname, p->base, p->irq);
>  
> -	pardev = parport_register_device(p,                     /* port */
> -					 DRIVER_NAME,           /* name */
> -					 NULL,                  /* preempt */
> -					 NULL,                  /* wakeup */
> -					 snd_portman_interrupt, /* ISR */
> -					 PARPORT_DEV_EXCL,      /* flags */
> -					 (void *)card);         /* private */
> +	portman_cb.private = card;			   /* private */
> +	pardev = parport_register_dev_model(p,		   /* port */
> +					    DRIVER_NAME,   /* name */
> +					    &portman_cb,   /* callbacks */
> +					    pdev->id);	   /* device number */
>  	if (pardev == NULL) {
>  		snd_printd("Cannot register pardevice\n");
>  		err = -EIO;
>  		goto __err;
>  	}
>  
> +	if (parport_claim(pardev)) {
> +		err = -EIO;
> +		goto free_pardev;
> +	}
> +
> +	err = portman_probe(p);
> +	parport_release(pardev);

Better to remove parport_claim() in snd_portman_probe() and keep
claiming.  Then pardev_claimed flag can be removed, too.


Takashi