On Thu, Feb 04, 2016 at 05:51:07PM +0100, Takashi Iwai wrote:
On Thu, 04 Feb 2016 17:38:23 +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 only change is in the way the driver gets registered with the parallel port subsystem and so as a result there is no user visible change or any chance of regression.
Signed-off-by: Sudip Mukherjee sudip@vectorindia.org
v3: changed commit message v2:
- 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 | 53 ++++++++++++++++++++++++++++++++++------------ 1 file changed, 39 insertions(+), 14 deletions(-)
diff --git a/sound/drivers/portman2x4.c b/sound/drivers/portman2x4.c index 172685d..a22f56c 100644 --- a/sound/drivers/portman2x4.c +++ b/sound/drivers/portman2x4.c @@ -650,10 +650,21 @@ 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);
- struct pardev_cb pdev_cb = {
.preempt = NULL,.wakeup = NULL,.private = NULL,.irq_func = NULL,.flags = 0,- };
- /*
* Specify the device number as SNDRV_CARDS + 1 so that the* device id alloted to this temporary device will never clash* with an actual device already registered.*/- pardev = parport_register_dev_model(p, DRIVER_NAME, &pdev_cb,
SNDRV_CARDS + 1);Hmm, doesn't this result in a device name like "xxx.33" ?
yes, it will. But this is a temoporary device just to check if the sound card is connected to that particular parallel port or not. After checking this device is immediately unregistered. My idea here was to have a device number which will never clash with another device number. And we can never have a device like "xxx.33", so no conflict. :)
Also, what if multiple portman devices are registered?
Even if we have multiple device, this temporary device will be unregistered immediately after checking for the soundcard. So we should not have any problem.
I suppose rather it should be passing dev variable from snd_portman_probe()?
Yes, we can. Instead of dev we can just pass the pdev->id for the device number. Then we can have the same device number for the temporary device used for probing and also the same number will be used in the actual device if probing succeeds. Whichever way you want. Shall I send the patch to use the same device number or using 33 as the device number will do?
regards sudip