[Letux-kernel] Charging on GTA04

H. Nikolaus Schaller hns at goldelico.com
Sun Jun 26 18:43:03 CEST 2016


> Am 26.06.2016 um 18:07 schrieb H. Nikolaus Schaller <hns at goldelico.com>:
> 
> 
>> Am 26.06.2016 um 17:12 schrieb H. Nikolaus Schaller <hns at goldelico.com>:
>> 
>> 
>>> Am 26.06.2016 um 15:01 schrieb H. Nikolaus Schaller <hns at goldelico.com>:
>>> 
>>> 
>>>> Am 24.06.2016 um 10:03 schrieb H. Nikolaus Schaller <hns at goldelico.com>:
>>>> 
>>>> Hi,
>>>> it appears as if USB detection is now completely broken on -rc4...
>>>> 
>>>> I have two boards where I neither get some "USB plugged in" nor
>>>> does /sys/class/power/usb start charging.
>>>> 
>>>> Something has gone wild.
>>>> 
>>>> Does it work for anyone of you?
>>> 
>>> Here some observations to this problem (using letux-4.7-rc4):
>>> 
>>> root at letux:/sys/class/power_supply/twl4030_usb# cat uevent 
>>> POWER_SUPPLY_NAME=twl4030_usb
>>> POWER_SUPPLY_STATUS=Not charging
>>> POWER_SUPPLY_ONLINE=0
>>> POWER_SUPPLY_INPUT_CURRENT_LIMIT=841
>>> root at letux:/sys/class/power_supply/twl4030_usb# echo continuous >mode
>>> root at letux:/sys/class/power_supply/twl4030_usb# cat mode
>>> off auto [continuous]
>>> root at letux:/sys/class/power_supply/twl4030_usb# cat uevent 
>>> POWER_SUPPLY_NAME=twl4030_usb
>>> POWER_SUPPLY_STATUS=Charging
>>> POWER_SUPPLY_ONLINE=1
>>> POWER_SUPPLY_VOLTAGE_NOW=0
>>> POWER_SUPPLY_CURRENT_NOW=12474
>>> POWER_SUPPLY_INPUT_CURRENT_LIMIT=841
>>> root at letux:/sys/class/power_supply/twl4030_usb# echo auto >mode
>>> [  189.735412] twl4030_bci 48070000.i2c:twl at 48:bci: battery temperature out of range
>>> [  189.766967] twl4030_bci 48070000.i2c:twl at 48:bci: battery temperature out of range
>>> root at letux:/sys/class/power_supply/twl4030_usb# cat uevent 
>>> POWER_SUPPLY_NAME=twl4030_usb
>>> POWER_SUPPLY_STATUS=Not charging
>>> POWER_SUPPLY_ONLINE=0
>>> POWER_SUPPLY_INPUT_CURRENT_LIMIT=841
>>> root at letux:/sys/class/power_supply/twl4030_usb# 
>>> 
>>> This means:
>>> 1.  "auto" mode is broken
>>> 2. continuous mode seems to charge
>>> 3. switching back to auto mode gives strange "battery temperature out of range" warning
>>> 
>>> And I have no ethernet-gadget.
>>> 
>>> I think I should compare with letux-4.6.0 or other -rc. And I should enable debugging
>>> of the driver.
>> 
>> Well, 4.6.0 isn't charging as well (and no ethernet gadget). And older versions are not properly booting.
>> 
>> One strange observation:
>> 
>> root at letux:~# cat /sys/class/power_supply/twl4030_usb/voltage_now
>> 0
>> root at letux:~# cat /sys/class/power_supply/twl4030_usb/uevent
>> POWER_SUPPLY_NAME=twl4030_usb
>> POWER_SUPPLY_STATUS=Charging
>> POWER_SUPPLY_ONLINE=1
>> POWER_SUPPLY_VOLTAGE_NOW=0
>> POWER_SUPPLY_CURRENT_NOW=808476
>> POWER_SUPPLY_INPUT_CURRENT_LIMIT=798505
>> root at letux:~# 
>> 
>> This means that voltage_now and POWER_SUPPLY_VOLTAGE_NOW is 0 although charging!
>> 
>> This is definitively different to 4.6.0 where USB voltage is displayed.
>> 
>> Is perhaps the madc broken?
> 
> Yes and no...
> 
> This is what I get with #define DEBUG
> 
> root at letux:~# dmesg|fgrep bci
> [    8.864227] driver_register 'twl4030_bci'
> [    8.864868] twl4030_bci_probe
> [    8.864959] twl4030_bci_probe: of_find_compatible_node
> [    8.865020] devm_usb_get_phy_by_node(ddcd2410 48070000.i2c:twl at 48:bci, df9b1af4 twl4030-usb, ddfad020)
> [    8.865051]   bci->transceiver = fffffdfb
> [    8.943939] twl4030_bci_probe
> [    8.944000] twl4030_bci_probe: of_find_compatible_node
> [    8.944061] devm_usb_get_phy_by_node(ddcd2410 48070000.i2c:twl at 48:bci, df9b1af4 twl4030-usb, ddfad020)
> [    8.944091]   bci->transceiver = fffffdfb
> [    8.953796] twl4030_bci_probe
> [    8.953857] twl4030_bci_probe: of_find_compatible_node
> [    8.953918] devm_usb_get_phy_by_node(ddcd2410 48070000.i2c:twl at 48:bci, df9b1af4 twl4030-usb, ddfad220)
> [    8.953948]   bci->transceiver = fffffdfb
> [    8.973114] twl4030_bci_probe
> [    8.973175] twl4030_bci_probe: of_find_compatible_node
> [    8.973236] devm_usb_get_phy_by_node(ddcd2410 48070000.i2c:twl at 48:bci, df9b1af4 twl4030-usb, ddfad220)
> [    8.973266]   bci->transceiver = fffffdfb
> [    8.988189] twl4030_bci_probe
> [    8.988250] twl4030_bci_probe: of_find_compatible_node
> [    8.988311] devm_usb_get_phy_by_node(ddcd2410 48070000.i2c:twl at 48:bci, df9b1af4 twl4030-usb, ddd99320)
> [    8.988342]   bci->transceiver = fffffdfb
> [    9.232696] twl4030_bci_probe
> [    9.232788] twl4030_bci_probe: of_find_compatible_node
> [    9.232849] devm_usb_get_phy_by_node(ddcd2410 48070000.i2c:twl at 48:bci, df9b1af4 twl4030-usb, ddd99320)
> [    9.232849]   bci->transceiver = fffffdfb
> [    9.238159] twl4030_bci_probe
> [    9.238250] twl4030_bci_probe: of_find_compatible_node
> [    9.238281] devm_usb_get_phy_by_node(ddcd2410 48070000.i2c:twl at 48:bci, df9b1af4 twl4030-usb, ddfad020)
> [    9.238311]   bci->transceiver = fffffdfb
> [    9.396270] twl4030_bci_probe
> [    9.396362] twl4030_bci_probe: of_find_compatible_node
> [    9.396392] devm_usb_get_phy_by_node(ddcd2410 48070000.i2c:twl at 48:bci, df9b1af4 twl4030-usb, dcac2f20)
> [    9.396423]   bci->transceiver = fffffdfb
> [    9.424865] twl4030_bci_probe
> [    9.424957] twl4030_bci_probe: of_find_compatible_node
> [    9.424987] devm_usb_get_phy_by_node(ddcd2410 48070000.i2c:twl at 48:bci, df9b1af4 twl4030-usb, ddfad020)
> [    9.425018]   bci->transceiver = fffffdfb
> [    9.477874] twl4030_bci_probe
> [    9.477966] twl4030_bci_probe: of_find_compatible_node
> [    9.477996] devm_usb_get_phy_by_node(ddcd2410 48070000.i2c:twl at 48:bci, df9b1af4 twl4030-usb, ddfad120)
> [    9.478027]   bci->transceiver = fffffdfb
> [    9.530670] twl4030_bci_probe
> [    9.530761] twl4030_bci_probe: of_find_compatible_node
> [    9.530822] devm_usb_get_phy_by_node(ddcd2410 48070000.i2c:twl at 48:bci, df9b1af4 twl4030-usb, ddfad720)
> [    9.530853]   bci->transceiver = dca39410
> [    9.530883] twl4030_bci 48070000.i2c:twl at 48:bci: could not request vac iio channel -19
> [    9.546997] twl4030_bci 48070000.i2c:twl at 48:bci: transceiver = dca39410
> [    9.546997] twl4030_bci 48070000.i2c:twl at 48:bci: OTG notify 0
> [    9.548370] twl4030_bci 48070000.i2c:twl at 48:bci: state: 00
> [    9.549224] twl4030_bci 48070000.i2c:twl at 48:bci: state: 00
> [    9.549804] twl4030_bci 48070000.i2c:twl at 48:bci: state: 00
> [    9.550292] twl4030_bci 48070000.i2c:twl at 48:bci: state: 00
> [    9.550781] twl4030_bci 48070000.i2c:twl at 48:bci: state: 00
> [    9.551300] twl4030_bci 48070000.i2c:twl at 48:bci: state: 00
> [    9.552612] twl4030_bci 48070000.i2c:twl at 48:bci: state: 00
> [    9.553131] twl4030_bci 48070000.i2c:twl at 48:bci: state: 00
> [    9.553558] twl4030_bci 48070000.i2c:twl at 48:bci: state: 00
> [    9.554046] twl4030_bci 48070000.i2c:twl at 48:bci: state: 00
> [    9.554534] twl4030_bci 48070000.i2c:twl at 48:bci: state: 00
> [    9.554992] twl4030_bci 48070000.i2c:twl at 48:bci: state: 00
> [    9.626617] twl4030_bci 48070000.i2c:twl at 48:bci: v=0 cur=-850000 limit=0 target=500000
> [   10.615722] twl4030_bci 48070000.i2c:twl at 48:bci: OTG notify 2
> [   12.135711] twl4030_bci 48070000.i2c:twl at 48:bci: state: 00
> [   12.136260] twl4030_bci 48070000.i2c:twl at 48:bci: state: 00
> [   12.136840] twl4030_bci 48070000.i2c:twl at 48:bci: state: 00
> [   12.137390] twl4030_bci 48070000.i2c:twl at 48:bci: state: 00
> [   12.137817] twl4030_bci 48070000.i2c:twl at 48:bci: state: 00
> [   12.139190] twl4030_bci 48070000.i2c:twl at 48:bci: state: 00
> [   12.139678] twl4030_bci 48070000.i2c:twl at 48:bci: state: 00
> [   12.140136] twl4030_bci 48070000.i2c:twl at 48:bci: state: 00
> [   12.140563] twl4030_bci 48070000.i2c:twl at 48:bci: state: 00
> [   12.141021] twl4030_bci 48070000.i2c:twl at 48:bci: state: 00
> [   12.143005] twl4030_bci 48070000.i2c:twl at 48:bci: state: 00
> [   12.143524] twl4030_bci 48070000.i2c:twl at 48:bci: state: 00
> [   12.143951] twl4030_bci 48070000.i2c:twl at 48:bci: state: 00
> [   12.144409] twl4030_bci 48070000.i2c:twl at 48:bci: state: 00
> [   12.144866] twl4030_bci 48070000.i2c:twl at 48:bci: state: 00
> [   12.146545] twl4030_bci 48070000.i2c:twl at 48:bci: state: 00
> [   12.146972] twl4030_bci 48070000.i2c:twl at 48:bci: state: 00
> [   12.147460] twl4030_bci 48070000.i2c:twl at 48:bci: state: 00
> [   12.147918] twl4030_bci 48070000.i2c:twl at 48:bci: state: 00
> [   12.165832] twl4030_bci 48070000.i2c:twl at 48:bci: state: 00
> [   12.168548] twl4030_bci 48070000.i2c:twl at 48:bci: state: 00
> [   12.169006] twl4030_bci 48070000.i2c:twl at 48:bci: state: 00
> [   12.169433] twl4030_bci 48070000.i2c:twl at 48:bci: state: 00
> [   12.169860] twl4030_bci 48070000.i2c:twl at 48:bci: state: 00
> [   12.170288] twl4030_bci 48070000.i2c:twl at 48:bci: state: 00
> [   12.198486] twl4030_bci 48070000.i2c:twl at 48:bci: state: 00
> [   12.201812] twl4030_bci 48070000.i2c:twl at 48:bci: state: 00
> [   12.202239] twl4030_bci 48070000.i2c:twl at 48:bci: state: 00
> [   12.202697] twl4030_bci 48070000.i2c:twl at 48:bci: state: 00
> [   12.203155] twl4030_bci 48070000.i2c:twl at 48:bci: state: 00
> [   12.211883] twl4030_bci 48070000.i2c:twl at 48:bci: state: 00
> [   12.212341] twl4030_bci 48070000.i2c:twl at 48:bci: state: 00
> [   12.212799] twl4030_bci 48070000.i2c:twl at 48:bci: state: 00
> [   12.213226] twl4030_bci 48070000.i2c:twl at 48:bci: state: 00
> [   12.213684] twl4030_bci 48070000.i2c:twl at 48:bci: state: 00
> [   12.216888] twl4030_bci 48070000.i2c:twl at 48:bci: state: 00
> [   12.217437] twl4030_bci 48070000.i2c:twl at 48:bci: state: 00
> [   12.217895] twl4030_bci 48070000.i2c:twl at 48:bci: state: 00
> [   12.219116] twl4030_bci 48070000.i2c:twl at 48:bci: state: 00
> [   12.219635] twl4030_bci 48070000.i2c:twl at 48:bci: state: 00
> [   12.419799] twl4030_bci 48070000.i2c:twl at 48:bci: state: 00
> [   12.423065] twl4030_bci 48070000.i2c:twl at 48:bci: state: 00
> [   12.423522] twl4030_bci 48070000.i2c:twl at 48:bci: state: 00
> [   12.423980] twl4030_bci 48070000.i2c:twl at 48:bci: state: 00
> [   12.424438] twl4030_bci 48070000.i2c:twl at 48:bci: state: 00
> [   12.426727] twl4030_bci 48070000.i2c:twl at 48:bci: state: 00
> [   12.427215] twl4030_bci 48070000.i2c:twl at 48:bci: state: 00
> [   12.427642] twl4030_bci 48070000.i2c:twl at 48:bci: state: 00
> [   12.428100] twl4030_bci 48070000.i2c:twl at 48:bci: state: 00
> [   12.428558] twl4030_bci 48070000.i2c:twl at 48:bci: state: 00
> [   12.430541] twl4030_bci 48070000.i2c:twl at 48:bci: state: 00
> [   12.431182] twl4030_bci 48070000.i2c:twl at 48:bci: state: 00
> [   12.431610] twl4030_bci 48070000.i2c:twl at 48:bci: state: 00
> [   12.432067] twl4030_bci 48070000.i2c:twl at 48:bci: state: 00
> [   12.432525] twl4030_bci 48070000.i2c:twl at 48:bci: state: 00
> [   12.447662] twl4030_bci 48070000.i2c:twl at 48:bci: state: 00
> [   12.448211] twl4030_bci 48070000.i2c:twl at 48:bci: state: 00
> [   12.448669] twl4030_bci 48070000.i2c:twl at 48:bci: state: 00
> [   12.449127] twl4030_bci 48070000.i2c:twl at 48:bci: state: 00
> [   12.449554] twl4030_bci 48070000.i2c:twl at 48:bci: state: 00
> root at letux:~# 
> 
> root at letux:~# echo auto >/sys/class/power_supply/twl4030_usb/mode
> [  280.254119] twl4030_bci 48070000.i2c:twl at 48:bci: BCI irq 00 08
> [  280.266662] twl4030_bci 48070000.i2c:twl at 48:bci: BCI irq 00 08
> [  280.279632] twl4030_bci 48070000.i2c:twl at 48:bci: state: 00
> root at letux:~# [  280.288757] twl4030_bci 48070000.i2c:twl at 48:bci: state: 00
> [  280.294769] twl4030_bci 48070000.i2c:twl at 48:bci: state: 00
> [  280.303192] twl4030_bci 48070000.i2c:twl at 48:bci: state: 00
> [  280.311340] twl4030_bci 48070000.i2c:twl at 48:bci: state: 00
> [  280.319427] twl4030_bci 48070000.i2c:twl at 48:bci: state: 00
> [  280.327392] twl4030_bci 48070000.i2c:twl at 48:bci: state: 00
> [  280.334716] twl4030_bci 48070000.i2c:twl at 48:bci: state: 00
> [  280.342620] twl4030_bci 48070000.i2c:twl at 48:bci: state: 00
> [  280.356506] twl4030_bci 48070000.i2c:twl at 48:bci: state: 00
> [  280.370605] twl4030_bci 48070000.i2c:twl at 48:bci: state: 00
> [  280.387207] twl4030_bci 48070000.i2c:twl at 48:bci: state: 00
> [  280.393249] twl4030_bci 48070000.i2c:twl at 48:bci: state: 00
> [  280.403289] twl4030_bci 48070000.i2c:twl at 48:bci: state: 00
> [  280.409912] twl4030_bci 48070000.i2c:twl at 48:bci: state: 00
> [  280.418304] twl4030_bci 48070000.i2c:twl at 48:bci: state: 00
> [  280.427124] twl4030_bci 48070000.i2c:twl at 48:bci: state: 00
> [  280.439941] twl4030_bci 48070000.i2c:twl at 48:bci: state: 00
> [  280.447601] twl4030_bci 48070000.i2c:twl at 48:bci: v=0 cur=9150 limit=0 target=500000
> [  280.452423] twl4030_bci 48070000.i2c:twl at 48:bci: state: 00
> [  280.461273] twl4030_bci 48070000.i2c:twl at 48:bci: state: 00
> [  280.465728] twl4030_bci 48070000.i2c:twl at 48:bci: state: 00
> [  280.466339] twl4030_bci 48070000.i2c:twl at 48:bci: state: 00
> [  280.466888] twl4030_bci 48070000.i2c:twl at 48:bci: state: 00
> [  280.467437] twl4030_bci 48070000.i2c:twl at 48:bci: state: 00
> [  280.467926] twl4030_bci 48070000.i2c:twl at 48:bci: state: 00
> [  280.476196] twl4030_bci 48070000.i2c:twl at 48:bci: state: 00
> [  280.488464] twl4030_bci 48070000.i2c:twl at 48:bci: state: 00
> [  280.490081] twl4030_bci 48070000.i2c:twl at 48:bci: state: 00
> [  280.502502] twl4030_bci 48070000.i2c:twl at 48:bci: state: 00
> [  280.514495] twl4030_bci 48070000.i2c:twl at 48:bci: state: 00
> [  280.557800] twl4030_bci 48070000.i2c:twl at 48:bci: state: 00
> [  280.576171] twl4030_bci 48070000.i2c:twl at 48:bci: state: 00
> [  280.586883] twl4030_bci 48070000.i2c:twl at 48:bci: state: 00
> [  280.607116] twl4030_bci 48070000.i2c:twl at 48:bci: state: 00
> [  280.622772] twl4030_bci 48070000.i2c:twl at 48:bci: state: 00
> [  280.629150] twl4030_bci 48070000.i2c:twl at 48:bci: state: 00
> [  280.638549] twl4030_bci 48070000.i2c:twl at 48:bci: state: 00
> [  280.646270] twl4030_bci 48070000.i2c:twl at 48:bci: state: 00
> [  280.652954] twl4030_bci 48070000.i2c:twl at 48:bci: state: 00
> [  280.659973] twl4030_bci 48070000.i2c:twl at 48:bci: state: 00
> [  280.667388] twl4030_bci 48070000.i2c:twl at 48:bci: state: 00
> [  280.674468] twl4030_bci 48070000.i2c:twl at 48:bci: state: 00
> [  280.681243] twl4030_bci 48070000.i2c:twl at 48:bci: state: 00
> [  280.689605] twl4030_bci 48070000.i2c:twl at 48:bci: state: 00
> [  280.700714] twl4030_bci 48070000.i2c:twl at 48:bci: state: 00
> [  280.708557] twl4030_bci 48070000.i2c:twl at 48:bci: state: 00
> [  280.716094] twl4030_bci 48070000.i2c:twl at 48:bci: state: 00
> [  280.722961] twl4030_bci 48070000.i2c:twl at 48:bci: state: 00
> [  280.731384] twl4030_bci 48070000.i2c:twl at 48:bci: state: 00
> [  280.739349] twl4030_bci 48070000.i2c:twl at 48:bci: state: 00
> [  280.747070] twl4030_bci 48070000.i2c:twl at 48:bci: state: 00
> [  280.754119] twl4030_bci 48070000.i2c:twl at 48:bci: state: 00
> [  280.761901] twl4030_bci 48070000.i2c:twl at 48:bci: state: 00
> 
> root at letux:~# echo continuous >/sys/class/power_supply/twl4030_usb/mode
> root at letux:~# [  324.358245] twl4030_bci 48070000.i2c:twl at 48:bci: BCI irq 00 10
> [  324.371276] twl4030_bci 48070000.i2c:twl at 48:bci: state: 00
> [  324.378295] twl4030_bci 48070000.i2c:twl at 48:bci: state: 00
> [  324.385040] twl4030_bci 48070000.i2c:twl at 48:bci: state: 00
> [  324.394165] twl4030_bci 48070000.i2c:twl at 48:bci: state: 00
> [  324.401306] twl4030_bci 48070000.i2c:twl at 48:bci: state: 00
> [  324.402191] twl4030_bci 48070000.i2c:twl at 48:bci: state: 00
> [  324.414855] twl4030_bci 48070000.i2c:twl at 48:bci: state: 00
> [  324.426727] twl4030_bci 48070000.i2c:twl at 48:bci: state: 00
> [  324.441223] twl4030_bci 48070000.i2c:twl at 48:bci: state: 00
> [  324.447875] twl4030_bci 48070000.i2c:twl at 48:bci: state: 00
> [  324.455444] twl4030_bci 48070000.i2c:twl at 48:bci: state: 00
> [  324.463897] twl4030_bci 48070000.i2c:twl at 48:bci: state: 00
> [  324.471313] twl4030_bci 48070000.i2c:twl at 48:bci: state: 00
> [  324.479522] twl4030_bci 48070000.i2c:twl at 48:bci: state: 00
> [  324.488952] twl4030_bci 48070000.i2c:twl at 48:bci: state: 00
> [  324.497528] twl4030_bci 48070000.i2c:twl at 48:bci: state: 00
> [  324.511199] twl4030_bci 48070000.i2c:twl at 48:bci: state: 00
> [  324.522888] twl4030_bci 48070000.i2c:twl at 48:bci: state: 00
> [  324.534454] twl4030_bci 48070000.i2c:twl at 48:bci: state: 00
> [  324.544067] twl4030_bci 48070000.i2c:twl at 48:bci: state: 00
> [  324.551605] twl4030_bci 48070000.i2c:twl at 48:bci: state: 00
> [  324.558898] twl4030_bci 48070000.i2c:twl at 48:bci: state: 00
> [  324.566894] twl4030_bci 48070000.i2c:twl at 48:bci: state: 00
> [  324.573669] twl4030_bci 48070000.i2c:twl at 48:bci: state: 00
> [  324.581848] twl4030_bci 48070000.i2c:twl at 48:bci: state: 00
> [  324.589080] twl4030_bci 48070000.i2c:twl at 48:bci: state: 00
> [  324.597717] twl4030_bci 48070000.i2c:twl at 48:bci: state: 00
> [  324.652496] twl4030_bci 48070000.i2c:twl at 48:bci: state: 00
> [  324.659973] twl4030_bci 48070000.i2c:twl at 48:bci: state: 00
> [  324.667877] twl4030_bci 48070000.i2c:twl at 48:bci: state: 00
> [  324.677307] twl4030_bci 48070000.i2c:twl at 48:bci: state: 00
> [  324.686981] twl4030_bci 48070000.i2c:twl at 48:bci: state: 00
> 
> Really interesting is
> 
> [    9.530883] twl4030_bci 48070000.i2c:twl at 48:bci: could not request vac iio channel -19
> 
> Which means there is some error in the madc iio subsystem at that stage.

Well, the bug is in one of our DT patches:

<http://git.goldelico.com/?p=gta04-kernel.git;a=blob;f=arch/arm/boot/dts/twl4030.dtsi;h=0c862d2d7b5aa7e8460b91d143d6245a5c5a8da8;hb=f704c620abd294972e754c8b59a085191e411da8#l27>

this line should read

		io-channel-names = "vac";

> 
> The second observation is that there is nothing happening on USB plug/unplug.
> 
> IMHO USB-Plug detection is also broken (don't know if hw or software).

Interestingly, I see different OTG notify values depending on whether
the cable is plugged in during boot or not. But no new notifications if I
unplug the cable.

Well, that is only part of the truth:

* if I take a short USB cable I can see notify 0 and notify 2 (but still no charging nor ethernet gadget)
* if I take a long cable and plug/unplug at the hub end, I don't see notifications
* if I take a long cable and plug/unplug at the gta04 end, I see notifications

* MADC reports some mV only for VBUS

That is really weird.

What could this be (if not a hardware problem)?

* USB/OTG detection is broken (some race between VBUS and D+/D- level detection on cable plug)
* charger is fully enabled (too high inrush-current) preventing VBUS to rising above the VBUS detection level
	with short cable I have 4.54V
	with long cable I have just 4.39V
* a bug in MADC so that VBUS is not reported properly
* is the OTG charge pump not being turned on/off?

More ideas?

BR,
Nikolaus



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