[Letux-kernel] wwan logic inversion

Sat Nov 24 09:29:38 CET 2018

> Am 23.11.2018 um 20:57 schrieb H. Nikolaus Schaller <hns at goldelico.com>:
> 
> Hi,
> 
>> Am 23.11.2018 um 18:19 schrieb H. Nikolaus Schaller <hns at goldelico.com>:
>> 
>> Unfortunately it is a little difficult to find a patch that has removed a specific line of code.
>> Finding the one that introduced a change is a simple git blame + grep
>> 
> 
> Here is the trick:
> 
> git log --oneline letux-4.19.3 -S 'modem_en' arch/arm/boot/dts/omap3-gta04a5.dts
> 
> Well, the result is empty!
> 
> So this means we have indeed lost this while reorganizing the feature branches
> for 4.19-rc1.
> 
> So in summary it is still in the letux/dt-gta04a5-v2 branch: http://git.goldelico.com/?p=letux-kernel.git;a=shortlog;h=refs/heads/work/letux-base/dt-gta04a5-v2
> 
> But that branch is no longer merged (since ca. 4 weeks ago) - assuming that we
> have everything we need in letux/dt-gta04-v3
> 
> http://git.goldelico.com/?p=letux-kernel.git;a=shortlog;h=refs/heads/letux/dt-gta04-v3 
> 
> But we haven't.
> 
> So I'll factor out the modem_en patch from
> 
> http://git.goldelico.com/?p=letux-kernel.git;a=blobdiff;f=arch/arm/boot/dts/omap3-gta04a5.dts;h=17a3dc11d420dc5953b98b53baa6199a8988f222;hp=600b6ca5a1bdc03795a85855c6394e6f1f2bf397;hb=dfb3da99842c6c8d4b6acfc94a778e034f5ee63e;hpb=84df9525b0c27f3ebc2ebb1864fa62a97fdedb7d
> 
> and apply to 4.19.4 and add to letux/dt-gta04-v3 so that it will be merged into
> letux.4-20-rc4 on Monday.
> 
> And of course test if it fixes the problem.

Hm. The strange thing is that I can't reproduce the problem with the 4.19.3 kernel:

root at letux:~# lsusb
Bus 002 Device 001: ID 1d6b:0002 Linux Foundation 2.0 root hub
Bus 001 Device 001: ID 1d6b:0002 Linux Foundation 2.0 root hub
root at letux:~# rfkill unblock wwan
[  250.358123] wwan_on_off_rfkill_set_block: blocked: 0
[  250.363800] wwan_on_off_set_power:on = 1
[  250.367950] wwan_on_off_is_powered_on: USB phy event 0
[  250.376647] wwan_on_off_is_powered_on: we assume 0
[  250.381652] wwan_on_off_is_powered_on: return 'false'
[  250.387542] wwan_on_off_set_power: state 0
[  250.391815] wwan_on_off_set_power: send impulse
[  251.133087] wwan_on_off_is_powered_on: USB phy event 0
[  251.138488] wwan_on_off_is_powered_on: we assume 1
[  251.145416] wwan_on_off_is_powered_on: return 'true'
[  251.150695] wwan_on_off_set_power: done
root at letux:~# [  253.403228] usb 1-2: new high-speed USB device number 2 using ehci-omap
[  253.607421] usb 1-2: New USB device found, idVendor=0af0, idProduct=8800, bcdDevice= 0.00
[  253.616210] usb 1-2: New USB device strings: Mfr=3, Product=2, SerialNumber=0
[  253.624969] usb 1-2: Product: Globetrotter HSUPA Modem
[  253.630432] usb 1-2: Manufacturer: Option N.V.
[  253.748168] hso: drivers/net/usb/hso.c: Option Wireless
[  253.774322] hso 1-2:1.5: Not our interface
[  253.785430] usbcore: registered new interface driver hso
rfkill block wwan
[  270.307037] wwan_on_off_rfkill_set_block: blocked: 1
[  270.312316] wwan_on_off_set_power:on = 0
[  270.318054] wwan_on_off_is_powered_on: USB phy event 0
[  270.325988] wwan_on_off_is_powered_on: we assume 1
[  270.330993] wwan_on_off_is_powered_on: return 'true'
[  270.336730] wwan_on_off_set_power: state 1
[  270.341003] wwan_on_off_set_power: send impulse
[  270.585662] usb 1-2: USB disconnect, device number 2
[  271.083068] wwan_on_off_is_powered_on: USB phy event 0
[  271.088470] wwan_on_off_is_powered_on: we assume 0
[  271.097381] wwan_on_off_is_powered_on: return 'false'
[  271.104705] wwan_on_off_set_power: done
root at letux:~# uname -a
Linux letux 4.19.3-letux+ #2950 SMP PREEMPT Fri Nov 23 21:39:00 CET 2018 armv7l GNU/Linux
root at letux:~# 

unblock -> turns on (connect)
block -> turns off (disconnect)

This experiement is obviously without feedback because the driver reports "we assume 1/0".

Now the same device with 4.19.4 and the patch:

root at letux:~# uname -a
Linux letux 4.19.4-letux+ #2951 SMP PREEMPT Sat Nov 24 09:13:20 CET 2018 armv7l GNU/Linux
root at letux:~# rfkill unblock wwan 
[   91.425201] wwan_on_off_rfkill_set_block: blocked: 0
[   91.430511] wwan_on_off_set_power:on = 1
[   91.436676] wwan_on_off_is_powered_on: gpio value = 0
[   91.442321] wwan_on_off_is_powered_on: return 'false'
[   91.450317] wwan_on_off_set_power: state 0
[   91.455017] wwan_on_off_set_power: send impulse
[   92.193634] wwan_on_off_is_powered_on: gpio value = 1
[   92.206604] wwan_on_off_is_powered_on: return 'true'
[   92.218933] wwan_on_off_set_power: done
root at letux:~# [   94.483642] usb 1-2: new high-speed USB device number 2 using ehci-omap
[   94.687927] usb 1-2: New USB device found, idVendor=0af0, idProduct=8800, bcdDevice= 0.00
[   94.696746] usb 1-2: New USB device strings: Mfr=3, Product=2, SerialNumber=0
[   94.705596] usb 1-2: Product: Globetrotter HSUPA Modem
[   94.711059] usb 1-2: Manufacturer: Option N.V.
[   94.827880] hso: drivers/net/usb/hso.c: Option Wireless
[   94.864959] hso 1-2:1.5: Not our interface
[   94.871704] usbcore: registered new interface driver hso

root at letux:~# rfkill block wwan
[  105.104675] wwan_on_off_rfkill_set_block: blocked: 1
[  105.109954] wwan_on_off_set_power:on = 0
[  105.116149] wwan_on_off_is_powered_on: gpio value = 1
[  105.121765] wwan_on_off_is_powered_on: return 'true'
[  105.130004] wwan_on_off_set_power: state 1
[  105.134979] wwan_on_off_set_power: send impulse
[  105.374511] usb 1-2: USB disconnect, device number 2
[  105.874023] wwan_on_off_is_powered_on: gpio value = 0
[  105.879638] wwan_on_off_is_powered_on: return 'false'
[  105.887756] wwan_on_off_set_power: done
root at letux:~# 

Here it seems to query the modem status pin (gpio value = 0/1).

Hope this helps to find out what is really going on.

BR,
Nikolaus