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Jeffery Miller 92e24e0e57 Input: psmouse - add delay when deactivating for SMBus mode
There is a period of time between the psmouse deactivate and the
ability to communicate with the SMBus companion. Insert a
sleep after the deactivate to account for the delay and ensure
the SMBus companion is responsive.

Attempting to read from the SMBus companion too quickly was causing
the touchpad on machines with an i801_smbus companion to stop working
after a sleep/resume cycle.

On resume the rmi4_smbus would fail with errors reading the SMBus version
number:
```
[5454] i2c_i801:i801_check_post:414: i801_smbus 0000:00:1f.3: No response
smbus_result: i2c-0 a=02c f=0000 c=fd BYTE_DATA rd res=-6
rmi4_smbus 0-002c: failed to get SMBus version number!
...
rmi4_f01 rmi4-00.fn01: Failed to restore normal operation: -6.
rmi4_f01 rmi4-00.fn01: Resume failed with code -6.
rmi4_physical rmi4-00: Failed to suspend functions: -6
rmi4_smbus 0-002c: Failed to resume device: -6
```
In this case the rmi_smb_get_version fails with -ENXIO if it happens too
soon after the preceding serio_resume -> psmouse_deactivate call.

On boot this issue could cause the touchpad to stay in the limited PS/2
mode. This only reproduced in 1 in 10 boots on the Lenovo T440p.
Failures in the log on boot would show up as:
```
psmouse serio1: synaptics: Trying to set up SMBus access
[122] i2c_i801:i801_check_post:437: i801_smbus 0000:00:1f.3: No response
psmouse serio1: synaptics: SMbus companion is not ready yet
```

Experimentation on the Lenovo T440p showed that a delay of 7-12ms on
resume allowed the companion to respond.

The 30ms delay in this patch was chosen based on the linux-input message:
Link: https://lore.kernel.org/all/BYAPR03MB47572F2C65E52ED673238D41B2439@BYAPR03MB4757.namprd03.prod.outlook.com/

Signed-off-by: Jeffery Miller <jefferymiller@google.com>
Link: https://lore.kernel.org/r/20230726025256.81174-1-jefferymiller@google.com
Signed-off-by: Dmitry Torokhov <dmitry.torokhov@gmail.com>
2023-07-25 22:07:42 -07:00
arch - Drop the __weak attribute from a function prototype as it otherwise 2023-06-25 10:13:17 -07:00
block block: make sure local irq is disabled when calling __blkcg_rstat_flush 2023-06-22 07:44:00 -06:00
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 dt-bindings: mms114: Add linux,keycodes property for touch keys 2023-07-18 23:21:11 -07:00
drivers Input: psmouse - add delay when deactivating for SMBus mode 2023-07-25 22:07:42 -07:00
fs for-6.4-rc7-tag 2023-06-23 16:09:53 -07:00
include Linux 6.4 2023-07-17 09:20:46 -07:00
init Objtool changes for v6.4: 2023-04-28 14:02:54 -07:00
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 workqueue: clean up WORK_* constant types, clarify masking 2023-06-23 12:08:14 -07:00
lib 19 hotfixes. 14 are cc:stable and the remainder address issues which were 2023-06-12 16:14:34 -07:00
LICENSES LICENSES: Add the copyleft-next-0.3.1 license 2022-11-08 15:44:01 +01:00
mm 19 hotfixes. 8 of these are cc:stable. 2023-06-20 17:20:22 -07:00
net netfilter pull request 23-06-21 2023-06-22 14:39:06 +02:00
rust Rust changes for v6.4 2023-04-30 11:20:22 -07:00
samples samples/bpf: Drop unnecessary fallthrough 2023-05-16 19:44:05 +02:00
scripts - Add a ORC format hash to vmlinux and modules in order for other tools 2023-06-25 10:00:17 -07:00
security selinux: don't use make's grouped targets feature yet 2023-06-01 13:56:13 -04:00
sound ASoC: Fix for v6.4 2023-06-21 15:23:23 +02:00
tools Networking fixes for 6.4-rc8, including fixes from ipsec, bpf, 2023-06-22 17:59:51 -07:00
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
.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 Linux 6.4 2023-07-17 09:20:46 -07:00
Makefile Linux 6.4 2023-06-25 16:29:58 -07:00
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.