Re: [PATCH 0/2] an additional path to control charging current

From: Heiko Thiery
Date: Wed Mar 03 2021 - 13:24:09 EST


Hi,

Am Mi., 3. März 2021 um 16:01 Uhr schrieb Heiko Thiery <heiko.thiery@xxxxxxxxx>:
>
> Hi Ray,
>
>
> > Currently, VBUS draw callback does no action when the
> > generic PHYs are used. The patches add an additional path
> > to control charging current through power supply property
> > POWER_SUPPLY_PROP_INPUT_CURRENT_LIMIT.
> >
> > Ray Chi (2):
> > usb: dwc3: add a power supply for current control
> > usb: dwc3: add an alternate path in vbus_draw callback
>
> While using next-20210303 this patchset leads to the following kernel crash on my board:
>
> ---- 8< ----
>
> [ 1.392084] VFIO - User Level meta-driver version: 0.3
> [ 1.398370] Unable to handle kernel NULL pointer dereference at virtual address 00000000000003a0
> [ 1.407552] Mem abort info:
> [ 1.410479] ESR = 0x96000004
> [ 1.413668] EC = 0x25: DABT (current EL), IL = 32 bits
> [ 1.419217] SET = 0, FnV = 0
> [ 1.422413] EA = 0, S1PTW = 0
> [ 1.425690] Data abort info:
> [ 1.428705] ISV = 0, ISS = 0x00000004
> [ 1.432715] CM = 0, WnR = 0
> [ 1.435821] [00000000000003a0] user address but active_mm is swapper
> [ 1.442458] Internal error: Oops: 96000004 [#1] PREEMPT SMP
> [ 1.448274] Modules linked in:
> [ 1.451469] CPU: 1 PID: 1 Comm: swapper/0 Not tainted 5.12.0-rc1-next-20210303-00005-g090e892099db #126
> [ 1.461269] Hardware name: Kontron pITX-imx8m (DT)
> [ 1.466268] pstate: 60000005 (nZCv daif -PAN -UAO -TCO BTYPE=--)
> [ 1.472538] pc : devm_power_supply_get_by_phandle+0xe4/0x148
> [ 1.478455] lr : dwc3_probe+0xbac/0xfa0
> [ 1.482462] sp : ffff800011f1bb00
> [ 1.485918] x29: ffff800011f1bb00 x28: 0000000000000000
> [ 1.491467] x27: ffff800011681078 x26: ffff8000115d048c
> [ 1.497016] x25: ffff0000c089ea00 x24: 0000000000000003
> [ 1.502564] x23: ffff0000c089ea00 x22: ffff800011b89948
> [ 1.508112] x21: 0000000000000003 x20: 00000000fffffdfb
> [ 1.513660] x19: ffff0000c03f1080 x18: 00000000000000c0
> [ 1.519209] x17: 0000000000000000 x16: 0000000000000000
> [ 1.524757] x15: fffffc0000001000 x14: 0000000000000000
> [ 1.530306] x13: 0000000000000000 x12: 0000000000000030
> [ 1.535853] x11: 0101010101010101 x10: ffff800011f1ba50
> [ 1.541402] x9 : ffff0000ff784c70 x8 : 0000000000000010
> [ 1.546950] x7 : ffff0000c03a5590 x6 : 0000000000000080
> [ 1.552498] x5 : ffff0000c0098000 x4 : 00000000000003a0
> [ 1.558047] x3 : ffff800011cb2dc8 x2 : 0000000000000000
> [ 1.563596] x1 : 0000000000000001 x0 : 0000000000000000
> [ 1.569146] Call trace:
> [ 1.571700] devm_power_supply_get_by_phandle+0xe4/0x148
> [ 1.577248] dwc3_probe+0xbac/0xfa0
> [ 1.580890] platform_probe+0x68/0xd8
> [ 1.584719] really_probe+0xe4/0x3c0
> [ 1.588454] driver_probe_device+0x58/0xb8
> [ 1.592733] device_driver_attach+0x74/0x80
> [ 1.597100] __driver_attach+0x58/0xe0
> [ 1.601016] bus_for_each_dev+0x74/0xc8
> [ 1.605020] driver_attach+0x24/0x30
> [ 1.608753] bus_add_driver+0x184/0x1e8
> [ 1.612758] driver_register+0x64/0x120
> [ 1.616764] __platform_driver_register+0x28/0x38
> [ 1.621675] dwc3_driver_init+0x1c/0x28
> [ 1.625684] do_one_initcall+0x74/0x1d0
> [ 1.629691] kernel_init_freeable+0x1d4/0x23c
> [ 1.634240] kernel_init+0x14/0x118
> [ 1.637885] ret_from_fork+0x10/0x30
> [ 1.641624] Code: 88027c01 35ffffa2 17fffe96 f9800091 (885f7c82)
> [ 1.647992] ---[ end trace c6e48cea897d0b0d ]---
> [ 1.652833] Kernel panic - not syncing: Attempted to kill init! exitcode=0x0000000b
> [ 1.660822] SMP: stopping secondary CPUs
> [ 1.664921] Kernel Offset: disabled
> [ 1.668560] CPU features: 0x00240002,2000200c
> [ 1.673106] Memory Limit: none
> [ 1.676296] ---[ end Kernel panic - not syncing: Attempted to kill init! exitcode=0x0000000b ]---
>
>
> ---- 8< ----

This fixes the crash.

diff --git a/drivers/usb/dwc3/core.c b/drivers/usb/dwc3/core.c
index d15f065849cd..94fdbe502ce9 100644
--- a/drivers/usb/dwc3/core.c
+++ b/drivers/usb/dwc3/core.c
@@ -1628,7 +1628,7 @@ static int dwc3_probe(struct platform_device *pdev)
assert_reset:
reset_control_assert(dwc->reset);

- if (!dwc->usb_psy)
+ if (dwc->usb_psy)
power_supply_put(dwc->usb_psy);

return ret;
@@ -1653,7 +1653,7 @@ static int dwc3_remove(struct platform_device *pdev)
dwc3_free_event_buffers(dwc);
dwc3_free_scratch_buffers(dwc);

- if (!dwc->usb_psy)
+ if (dwc->usb_psy)
power_supply_put(dwc->usb_psy);

return 0;


--
Heiko