Re: [PATCH] Input: xen-kbdfront - allow better run-time configuration

[Juergen Gross]

On 19/04/18 13:44, Oleksandr Andrushchenko wrote:
> On 04/19/2018 02:25 PM, Juergen Gross wrote:
>> On 18/04/18 17:04, Oleksandr Andrushchenko wrote:
>>> From: Oleksandr Andrushchenko <oleksandr_andrushchenko@xxxxxxxx>
>>>
>>> It is now only possible to control if multi-touch virtual device
>>> is created or not (via the corresponding XenStore entries),
>>> but keyboard and pointer devices are always created.
>> Why don't you want to go that route for keyboard and mouse, too?
>> Or does this really make no sense?
> Well, I would prefer not to touch anything outside Linux and
> this driver. And these settings seem to be implementation specific.
> So, this is why introduce Linux module parameters and don't extend
> the kbdif protocol.
>>> In some cases this is not desirable. For example, if virtual
>>> keyboard device is exposed to Android then the latter won't
>>> automatically show on-screen keyboard as it expects that a
>>> physical keyboard device can be used for typing.
>>>
>>> Make it possible to configure which virtual devices are created
>>> with module parameters:
>>> ÂÂ - no_ptr_dev=1 if no pointer device needs to be created
>>> ÂÂ - no_kbd_dev=1 if no keyboard device needs to be created
>>> Keep old behavior by default.
>>>
>>> Signed-off-by: Oleksandr Andrushchenko
>>> <oleksandr_andrushchenko@xxxxxxxx>
>>> Suggested-by: Andrii Chepurnyi <andrii_chepurnyi@xxxxxxxx>
>>> Tested-by: Andrii Chepurnyi <andrii_chepurnyi@xxxxxxxx>
>>> ---
>>> Â drivers/input/misc/xen-kbdfront.c | 159 +++++++++++++++++-------------
>>> Â 1 file changed, 92 insertions(+), 67 deletions(-)
>>>
>>> diff --git a/drivers/input/misc/xen-kbdfront.c
>>> b/drivers/input/misc/xen-kbdfront.c
>>> index d91f3b1c5375..a3306aad40b0 100644
>>> --- a/drivers/input/misc/xen-kbdfront.c
>>> +++ b/drivers/input/misc/xen-kbdfront.c
>>> @@ -51,6 +51,16 @@ module_param_array(ptr_size, int, NULL, 0444);
>>> Â MODULE_PARM_DESC(ptr_size,
>>> ÂÂÂÂÂ "Pointing device width, height in pixels (default 800,600)");
>>> Â +static unsigned int no_ptr_dev;
>>> +module_param(no_ptr_dev, uint, 0);
>> Use type invbool instead?
> Hm, better bool then? invbool will require parameter name change to
> something like "with_ptr_dev" which might confuse, e.g.
> default was to go with pointer device, now we have with_ptr_dev
> module parameter: do I now need to set it to preserve the old behavior?
> The answer is no (because of invbool), but you have to dig for it.
> 
> Will bool work for you?

As long as the default won't change from today: yes.


Juergen