On Tuesday 02 December 2014 12:06:45 Gabriele Mazzotta wrote: > On Thursday 27 November 2014 12:41:19 Alex Hung wrote: > > On Sun, Nov 23, 2014 at 8:52 AM, Pali Rohár <pali.rohar@xxxxxxxxx> wrote: > > > On Saturday 22 November 2014 03:09:06 Darren Hart wrote: > > >> On Sat, Nov 22, 2014 at 11:45:08PM +0100, Pali Rohár wrote: > > >> > Hello, > > >> > > > >> > I saw dell-wireless driver on platform-driver-x86 > > >> > mailinglist [1] which using DELLABCE acpi device and I > > >> > do not like some parts in this driver. > > >> > > >> Hi Pali, > > >> > > >> Thanks for reviewing and speaking up :) > > >> > > >> > First is that this driver export rfkill event as > > >> > keypress which is also reported to userspace by > > >> > keyboard controller. So then userspace receive two > > >> > rfkill keypresses. > > >> > > >> Alex, can you comment? Does the keyboard controller also > > >> see this event? > > > > > > Yes on my laptop E6440. But it looks like it does not have > > > to be truth for all laptops... > > > > > >> > Second is that DELLABCE acpi device can also control > > >> > "soft" rfkill status and this driver does not enable > > >> > it because it use input class instead rfkill. > > >> > > > >> > Anyway I have unfinished my version of DELLABCE acpi > > >> > driver which will use rfkill interface and plus allow > > >> > to use hw switch events in dell-laptop.ko driver. > > >> > > >> Is this something that could be applied incrementally fo > > >> Alex's driver, or is it something we'd be best starting > > >> over with? > > > > > > Alex's driver is different. It registers input device. My > > > approach register rfkill device plus add exported > > > functions for registering atomic notifier (so other > > > drivers like dell-laptop can use events too). > > > > > > First we need to know if input driver is really needed. > > > And if yes determinate in which conditions and for which > > > laptops. Really duplicate key press are not good. > > > > > > In case when input driver is really needed I can just copy > > > relevant input code and add it into my driver (in case > > > when my driver will be used instead Alex's). This could > > > be no problem, because my and Alex code doing different > > > things and so could coexist in one driver (but cannot be > > > split into more because only one acpi driver can handle > > > one acpi device). > > > > > >> We have some precedent for input drivers (there is one > > >> nearly identical to the dell driver for hp, also by > > >> Alex). Using rfkill does seem like the better approach > > >> without digging into it. > > > > > > It is different from HP. Dell ACPI device on some machines > > > can also control wifi switches (it can enable/disable > > > it!). > > > > > > So it make sense to use rfkill. But on some machines that > > > ACPI device can only receive events that HW switch was > > > switched, but it is possible to ask for state (if is > > > enabled or not). HP driver just report switch was > > > changed, but does not report if is enabled or disabled. > > > > > > So I think HP is not identical to this Dell one. > > > > I can provide a little more information on HP and Dell's > > design. > > > > Dell's design is more complex than HP's indeed. > > > > HP BIOS will send ACPI notification when hotkey is pressed; > > especially HP uses buttons instead of hardware slider on > > their systems. > > > > Dell has two design > > 1. Button similar to HP. My patch targeted this type. > > 2. Hardware slider. This handled will handled by Wireless > > device drivers (ex. WLAN, BT and so on) by their rfkill > > hard-block. There is no need to handle this case. > > > > This can be distinguished by calling CRBT. I checked Pali's > > patch and it was used but the two types are not > > distinguished. You may want to use it as hard-block can be > > out-of-sync with soft-block on corner cases for Type 2. > > Hi, > > my laptop (XPS13 9333) supports both the switch types taken > into account in your patch. I can switch between them by > calling a method named ARBT. > > I can see that in your patch CRBT is called to determine the > switch type. On my system, that method always returns 0, > independently on the current mode. I have to verify this, but > I think that would be a problem on my system as by default > the BIOS uses what you called "design 2" and there are > currently no ways to change it. That means that with your > driver KEY_RFKILL would be sent along with the rfkill event. > To make things worse, dell-wmi is currently sending KEY_WLAN > when I press the Fn key that toggles the state of WiFi and > Bluetooth. > > I think that calling ARBT on driver init would solve all the > problems: the correct mode would get selected, the BIOS would > stop sending the WMI events that make dell-wmi send KEY_WLAN > and it would also no longer hard block the rfkill, letting > userspace applications take care of everything. > > As I said, I have to look into this better and I'll do it as > soon as I can. Sorry for being late. > > Gabriele > Ok, thanks for info. Alex, do you have documentation what ARBT acpi function exactly doing on machines with HW switch and on machines with Fn wifi key? > > >> > Currently dell-laptop.ko driver is using i8042 hook > > >> > function for detecting hw switch key press event. It > > >> > is needed to detect if rfkill state was changed or > > >> > not. > > >> > > > >> > My prepared patches for dell-laptop.ko allows to use > > >> > acpi event from DELLABCE driver, so i8042 hook > > >> > function can be dropped. Really it is not good idea to > > >> > pass every PS/2 data from both keyboard, touchpad and > > >> > trackpoint to dell-laptop driver and if there is > > >> > alternative (DELLABCE) it is better to use it. > > >> > > > >> > But now I would like to hear what do you think about > > >> > it. > > >> > > > >> > Because only one kernel driver can attach to DELLABCE > > >> > acpi device, I cannot use new dell-wireless driver. > > >> > And I think only one driver can hit mainline kernel. > > >> > > >> I would like to see your patch, it sounds like it might > > >> be a better option. > > > > > > Ok, I will sent patches. There are some problems which I'm > > > trying to fix together with Gabriele. Do you need to see > > > patches now, or can you wait some time until we fix it? > > > > > > -- > > > Pali Rohár > > > pali.rohar@xxxxxxxxx -- Pali Rohár pali.rohar@xxxxxxxxx
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