kernel/linux
0
Fork 0
mirror of https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git/ synced 2026-11-08 18:57:22 +00:00
Code Issues Releases Packages Activity
No description
1,187,620 commits 117 branches 5,824 tags 6.2 GiB
  • C 96.8%
  • Assembly 0.9%
  • Rust 0.7%
  • Shell 0.6%
  • Python 0.5%
  • Other 0.3%
Find a file
Nícolas F. R. A. Prado 686a663a36 drm/bridge: anx7625: Prevent endless probe loop 
[ Upstream commit 1464e48d69 ]

During probe, the driver registers i2c dummy devices and populates the
aux bus, which registers a device for the panel. After doing that, the
driver can still defer probe if needed. This ordering of operations is
troublesome however, because the deferred probe work will retry probing
all pending devices every time a new device is registered. Therefore, if
modules need to be loaded in order to satisfy the dependencies for this
driver to complete probe, the kernel will stall, since it'll keep trying
to probe the anx7625 driver, but never succeed, given that modules would
only be loaded after the deferred probe work completes.

Two changes are required to avoid this issue:
* Move of_find_mipi_dsi_host_by_node(), which can defer probe, to before
  anx7625_register_i2c_dummy_clients() and
  devm_of_dp_aux_populate_ep_devices(), which register devices.
* Make use of the done_probing callback when populating the aux bus,
  so that the bridge registration is only done after the panel is
  probed. This is required because the panel might need to defer probe,
  but the aux bus population needs the i2c dummy devices working, so
  this call couldn't just be moved to an earlier point in probe.
  One caveat is that if the panel is described outside the aux bus, the
  probe loop issue can still happen, but we don't have a way to avoid
  it in that case since there's no callback available.

With this patch applied, it's possible to boot on
mt8192-asurada-spherion with

CONFIG_DRM_ANALOGIX_ANX7625=y
CONFIG_MTK_MMSYS=m
CONFIG_BACKLIGHT_PWM=y

and also with

CONFIG_DRM_ANALOGIX_ANX7625=y
CONFIG_MTK_MMSYS=y
CONFIG_BACKLIGHT_PWM=m

Fixes: adca62ec37 ("drm/bridge: anx7625: Support reading edid through aux channel")
Fixes: 269332997a ("drm/bridge: anx7625: Return -EPROBE_DEFER if the dsi host was not found")
Reported-by: "kernelci.org bot" <bot@kernelci.org>
Signed-off-by: Nícolas F. R. A. Prado <nfraprado@collabora.com>
Reviewed-by: Robert Foss <rfoss@kernel.org>
Signed-off-by: Robert Foss <rfoss@kernel.org>
Link: https://patchwork.freedesktop.org/patch/msgid/20230518193902.891121-1-nfraprado@collabora.com
Signed-off-by: Sasha Levin <sashal@kernel.org>
History 2023-07-19 16:35:47 +02:00
arch arm64: dts: qcom: qrb4210-rb2: Fix CD gpio for SDHC2 2023-07-19 16:35:46 +02:00
block blk-mq: don't insert passthrough request into sw queue 2023-07-19 16:35:14 +02:00
certs KEYS: Add missing function documentation 2023-04-24 16:15:52 +03:00
crypto KEYS: asymmetric: Copy sig and digest in public_key_verify_signature() 2023-06-02 15:36:23 +02:00
Documentation ASoC: dt-bindings: mediatek,mt8188-afe: correct clock name 2023-07-19 16:35:42 +02:00
drivers drm/bridge: anx7625: Prevent endless probe loop 2023-07-19 16:35:47 +02:00
fs ocfs2: Fix use of slab data with sendpage 2023-07-19 16:35:36 +02:00
include drm: Add fixed-point helper to get rounded integer values 2023-07-19 16:35:43 +02:00
init start_kernel: Add __no_stack_protector function attribute 2023-07-19 16:35:05 +02:00
io_uring io_uring/net: use the correct msghdr union member in io_sendmsg_copy_hdr 2023-06-21 07:34:17 -06:00
ipc Merge branch 'work.namespace' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs 2023-02-24 19:20:07 -08:00
kernel watchdog/hardlockup: keep kernel.nmi_watchdog sysctl as 0444 if probe fails 2023-07-19 16:35:33 +02:00
lib lib/ts_bm: reset initial match offset for every block of text 2023-07-19 16:35:37 +02:00
LICENSES LICENSES: Add the copyleft-next-0.3.1 license 2022-11-08 15:44:01 +01:00
mm splice: Fix filemap_splice_read() to use the correct inode 2023-07-19 16:35:07 +02:00
net netlink: Add __sock_i_ino() for __netlink_diag_dump(). 2023-07-19 16:35:38 +02:00
rust Rust changes for v6.4 2023-04-30 11:20:22 -07:00
samples samples/bpf: xdp1 and xdp2 reduce XDPBUFSIZE to 60 2023-07-19 16:35:25 +02:00
scripts scripts/tags.sh: Resolve gtags empty index generation 2023-07-05 18:30:30 +01:00
security ima: Fix build warnings 2023-07-19 16:35:20 +02:00
sound ASoC: Intel: sof_sdw: start set codec init function with an adr index 2023-07-19 16:35:43 +02:00
tools selftests: rtnetlink: remove netdevsim device after ipsec offload test 2023-07-19 16:35:36 +02:00
usr initramfs: Check negative timestamp to prevent broken cpio archive 2023-04-16 17:37:01 +09:00
virt KVM: Avoid illegal stage2 mapping on invalid memory slot 2023-06-22 15:14:57 -04:00
.clang-format cxl for v6.4 2023-04-30 11:51:51 -07:00
.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 *.dtso files 2023-02-26 15:28:23 +09:00
.gitignore linux-kselftest-kunit-6.4-rc1 2023-04-24 12:31:32 -07:00
.mailmap mailmap: add entries for Ben Dooks 2023-06-19 13:19:35 -07:00
.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: sctp: move Neil to CREDITS 2023-05-12 08:51:32 +01:00
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 Networking fixes for 6.4-rc8, including fixes from ipsec, bpf, 2023-06-22 17:59:51 -07:00
Makefile Linux 6.4.3 2023-07-11 06:31:05 +02:00
README Drop all 00-INDEX files from Documentation/ 2018-09-09 15:08:58 -06:00

README 

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.