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Fabrice Gasnier bf337056c9 usb: dwc2: fix a race, don't power off/on phy for dual-role mode
commit 5021383242 upstream.

When in dual role mode (dr_mode == USB_DR_MODE_OTG), platform probe
successively basically calls:
- dwc2_gadget_init()
- dwc2_hcd_init()
- dwc2_lowlevel_hw_disable() since recent change [1]
- usb_add_gadget_udc()

The PHYs (and so the clocks it may provide) shouldn't be disabled for all
SoCs, in OTG mode, as the HCD part has been initialized.

On STM32 this creates some weird race condition upon boot, when:
- initially attached as a device, to a HOST
- and there is a gadget script invoked to setup the device part.
Below issue becomes systematic, as long as the gadget script isn't
started by userland: the hardware PHYs (and so the clocks provided by the
PHYs) remains disabled.
It ends up in having an endless interrupt storm, before the watchdog
resets the platform.

[   16.924163] dwc2 49000000.usb-otg: EPs: 9, dedicated fifos, 952 entries in SPRAM
[   16.962704] dwc2 49000000.usb-otg: DWC OTG Controller
[   16.966488] dwc2 49000000.usb-otg: new USB bus registered, assigned bus number 2
[   16.974051] dwc2 49000000.usb-otg: irq 77, io mem 0x49000000
[   17.032170] hub 2-0:1.0: USB hub found
[   17.042299] hub 2-0:1.0: 1 port detected
[   17.175408] dwc2 49000000.usb-otg: Mode Mismatch Interrupt: currently in Host mode
[   17.181741] dwc2 49000000.usb-otg: Mode Mismatch Interrupt: currently in Host mode
[   17.189303] dwc2 49000000.usb-otg: Mode Mismatch Interrupt: currently in Host mode
...

The host part is also not functional, until the gadget part is configured.

The HW may only be disabled for peripheral mode (original init), e.g.
dr_mode == USB_DR_MODE_PERIPHERAL, until the gadget driver initializes.

But when in USB_DR_MODE_OTG, the HW should remain enabled, as the HCD part
is able to run, while the gadget part isn't necessarily configured.

I don't fully get the of purpose the original change, that claims disabling
the hardware is missing. It creates conditions on SOCs using the PHY
initialization to be completely non working in OTG mode. Original
change [1] should be reworked to be platform specific.

[1] https://lore.kernel.org/r/20221206-dwc2-gadget-dual-role-v1-2-36515e1092cd@theobroma-systems.com

Fixes: ade23d7b7e ("usb: dwc2: power on/off phy for peripheral mode in dual-role mode")
Cc: stable <stable@kernel.org>
Signed-off-by: Fabrice Gasnier <fabrice.gasnier@foss.st.com>
Reviewed-by: Quentin Schulz <quentin.schulz@theobroma-systems.com>
Tested-by: Quentin Schulz <quentin.schulz@theobroma-systems.com>
Link: https://lore.kernel.org/r/20230315144433.3095859-1-fabrice.gasnier@foss.st.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
History 2023-03-30 12:51:33 +02:00
arch x86/fpu/xstate: Prevent false-positive warning in __copy_xstate_uabi_buf() 2023-03-30 12:51:33 +02:00
block block: count 'ios' and 'sectors' when io is done for bio-based device 2023-03-22 13:37:50 +01:00
certs certs: Fix build error when PKCS#11 URI contains semicolon 2023-01-31 17:53:01 +09:00
crypto crypto: rsa-pkcs1pad - Use akcipher_request_complete 2023-03-10 09:28:18 +01:00
Documentation docs: Correct missing "d_" prefix for dentry_operations member d_weak_revalidate 2023-03-22 13:37:42 +01:00
drivers usb: dwc2: fix a race, don't power off/on phy for dual-role mode 2023-03-30 12:51:33 +02:00
fs cifs: fix dentry lookups in directory handle cache 2023-03-30 12:51:32 +02:00
include entry: Fix noinstr warning in __enter_from_user_mode() 2023-03-30 12:51:24 +02:00
init Kbuild fixes for v6.2 (3rd) 2023-01-21 10:56:37 -08:00
io_uring io_uring/msg_ring: let target know allocated index 2023-03-22 13:38:08 +01:00
ipc Non-MM patches for 6.2-rc1. 2022-12-12 17:28:58 -08:00
kernel entry/rcu: Check TIF_RESCHED _after_ delayed RCU wake-up 2023-03-30 12:51:24 +02:00
lib cpuidle: lib/bug: Disable rcu_is_watching() during WARN/BUG 2023-03-10 09:29:06 +01:00
LICENSES LICENSES: Add the copyleft-next-0.3.1 license 2022-11-08 15:44:01 +01:00
mm mm: teach mincore_hugetlb about pte markers 2023-03-22 13:38:07 +01:00
net act_mirred: use the backlog for nested calls to mirred ingress 2023-03-30 12:51:31 +02:00
rust rust: print: avoid evaluating arguments in pr_* macros in unsafe blocks 2023-01-16 00:54:35 +01:00
samples ftrace: Export ftrace_free_filter() to modules 2023-01-24 11:20:58 -05:00
scripts kconfig: Update config changed flag before calling callback 2023-03-22 13:37:55 +01:00
security keys: Do not cache key in task struct if key is requested from kernel thread 2023-03-30 12:50:57 +02:00
sound ASoC: amd: yc: Add DMI entries to support HP OMEN 16-n0xxx (8A43) 2023-03-30 12:51:27 +02:00
tools selftests/x86/amx: Add a ptrace test 2023-03-30 12:51:33 +02:00
usr usr/gen_init_cpio.c: remove unnecessary -1 values from int file 2022-10-03 14:21:44 -07:00
virt KVM: Register /dev/kvm as the _very_ last thing during initialization 2023-03-10 09:29:33 +01:00
.clang-format iommufd for 6.2 2022-12-14 09:15:43 -08:00
.cocciconfig scripts: add Linux .cocciconfig for coccinelle 2016-07-22 12:13:39 +02:00
.get_maintainer.ignore get_maintainer: add Alan to .get_maintainer.ignore 2022-08-20 15:17:44 -07:00
.gitattributes .gitattributes: use 'dts' diff driver for dts files 2019-12-04 19:44:11 -08:00
.gitignore .gitignore: ignore *.rpm 2022-12-30 17:22:14 +09:00
.mailmap 12 hotfixes, mostly against mm/. Five of these fixes are cc:stable. 2023-02-13 14:09:20 -08:00
.rustfmt.toml rust: add .rustfmt.toml 2022-09-28 09:02:20 +02:00
COPYING COPYING: state that all contributions really are covered by this file 2020-02-10 13:32:20 -08:00
CREDITS MAINTAINERS: update SCTP maintainers 2023-02-02 11:35:33 -08:00
Kbuild Kbuild updates for v6.1 2022-10-10 12:00:45 -07:00
Kconfig kbuild: ensure full rebuild when the compiler is updated 2020-05-12 13:28:33 +09:00
MAINTAINERS audit: update the mailing list in MAINTAINERS 2023-02-25 11:13:29 +01:00
Makefile Linux 6.2.8 2023-03-22 13:38:11 +01:00
README Drop all 00-INDEX files from Documentation/ 2018-09-09 15:08:58 -06:00

Linux kernel
============

There are several guides for kernel developers and users. These guides can
be rendered in a number of formats, like HTML and PDF. Please read
Documentation/admin-guide/README.rst first.

In order to build the documentation, use ``make htmldocs`` or
``make pdfdocs``.  The formatted documentation can also be read online at:

    https://www.kernel.org/doc/html/latest/

There are various text files in the Documentation/ subdirectory,
several of them using the Restructured Text markup notation.

Please read the Documentation/process/changes.rst file, as it contains the
requirements for building and running the kernel, and information about
the problems which may result by upgrading your kernel.