linux/Documentation
Matthias Kaehlcke b4e326165e USB: misc: Add onboard_usb_hub driver
The main issue this driver addresses is that a USB hub needs to be
powered before it can be discovered. For discrete onboard hubs (an
example for such a hub is the Realtek RTS5411) this is often solved
by supplying the hub with an 'always-on' regulator, which is kind
of a hack. Some onboard hubs may require further initialization
steps, like changing the state of a GPIO or enabling a clock, which
requires even more hacks. This driver creates a platform device
representing the hub which performs the necessary initialization.
Currently it only supports switching on a single regulator, support
for multiple regulators or other actions can be added as needed.
Different initialization sequences can be supported based on the
compatible string.

Besides performing the initialization the driver can be configured
to power the hub off during system suspend. This can help to extend
battery life on battery powered devices which have no requirements
to keep the hub powered during suspend. The driver can also be
configured to leave the hub powered when a wakeup capable USB device
is connected when suspending, and power it off otherwise.

Technically the driver consists of two drivers, the platform driver
described above and a very thin USB driver that subclasses the
generic driver. The purpose of this driver is to provide the platform
driver with the USB devices corresponding to the hub(s) (a hub
controller may provide multiple 'logical' hubs, e.g. one to support
USB 2.0 and another for USB 3.x).

Note: the current series only supports hubs connected directly to
a root hub (through xhci-plat), support for other configurations
could be added if needed.

Co-developed-by: Ravi Chandra Sadineni <ravisadineni@chromium.org>
Acked-by: Alan Stern <stern@rowland.harvard.edu>
Signed-off-by: Ravi Chandra Sadineni <ravisadineni@chromium.org>
Signed-off-by: Matthias Kaehlcke <mka@chromium.org>
Link: https://lore.kernel.org/r/20210609150159.v12.2.I7c9a1f1d6ced41dd8310e8a03da666a32364e790@changeid
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2021-06-15 15:48:35 +02:00
..
ABI USB: misc: Add onboard_usb_hub driver 2021-06-15 15:48:35 +02:00
accounting
admin-guide Networking fixes for 5.13-rc4, including fixes from bpf, netfilter, 2021-05-26 17:44:49 -10:00
arm It's been a relatively busy cycle in docsland, though more than usually 2021-04-26 13:22:43 -07:00
arm64 Assorted arm64 fixes and clean-ups, the most important: 2021-05-07 12:11:05 -07:00
block Documentation: drop optional BOMs 2021-05-10 15:17:34 -06:00
bpf bpf: Document the pahole release info related to libbpf in bpf_devel_QA.rst 2021-04-23 17:11:58 -07:00
cdrom docs: cdrom-standard.rst: get rid of uneeded UTF-8 chars 2021-05-11 11:00:17 -06:00
core-api A few late-arriving documentation fixes, including some oprofile cleanup, a 2021-05-06 08:33:54 -07:00
cpu-freq
crypto
dev-tools scripts/gdb: add lx_current support for arm64 2021-05-07 00:26:33 -07:00
devicetree dt-bindings: usb: Add binding for Realtek RTS5411 hub controller 2021-06-15 15:48:35 +02:00
doc-guide
driver-api Merge 5.13-rc4 into usb-next 2021-05-31 09:50:26 +02:00
fault-injection
fb Documentation: Add leading slash to some paths 2021-03-31 13:49:19 -06:00
features powerpc updates for 5.13 2021-04-30 12:22:28 -07:00
filesystems erofs: update documentation about data compression 2021-05-11 16:47:15 +08:00
firmware_class
firmware-guide Documentation: firmware-guide: gpio-properties: Add note to SPI CS case 2021-04-28 19:11:13 +02:00
fpga Documentation: fpga: dfl: Add description for DFL UIO support 2021-03-28 14:58:18 +02:00
gpu drm-misc-next for 5.13: 2021-04-07 17:32:12 +10:00
hid Documentation: Add leading slash to some paths 2021-03-31 13:49:19 -06:00
hwmon docs: hwmon: tmp103.rst: fix bad usage of UTF-8 chars 2021-05-11 11:00:18 -06:00
i2c
ia64
ide
iio
infiniband
input Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/dtor/input 2021-05-06 23:37:55 -07:00
isdn
kbuild Kconfig updates for v5.13 2021-04-29 14:32:00 -07:00
kernel-hacking
leds Documentation: Add leading slash to some paths 2021-03-31 13:49:19 -06:00
litmus-tests
livepatch
locking
m68k
maintainer
mhi
mips
misc-devices dw-xdata-pcie: Update outdated info and improve text format 2021-04-14 19:47:28 +02:00
netlabel
networking docs: networking: device_drivers: fix bad usage of UTF-8 chars 2021-05-11 11:00:18 -06:00
nios2
nvdimm
openrisc
parisc
PCI
pcmcia
power power supply and reset changes for the v5.13 series 2021-04-28 15:43:58 -07:00
powerpc powerpc/64s/syscall: Use pt_regs.trap to distinguish syscall ABI difference between sc and scv syscalls 2021-05-21 00:58:03 +10:00
process Documentation: drop optional BOMs 2021-05-10 15:17:34 -06:00
RCU
riscv Documentation: riscv: Add documentation that describes the VM layout 2021-04-26 08:25:05 -07:00
s390 s390/pci: expose UID uniqueness guarantee 2021-04-05 11:30:57 +02:00
scheduler sched,doc: sched_debug_verbose cmdline should be sched_verbose 2021-05-06 15:33:26 +02:00
scsi for-5.13/block-2021-04-27 2021-04-28 14:27:12 -07:00
security Documentation: drop optional BOMs 2021-05-10 15:17:34 -06:00
sh
sound
sparc
sphinx
sphinx-static
spi spi: Updates for v5.13 2021-04-26 16:32:11 -07:00
staging
target
timers Documentation: drop optional BOMs 2021-05-10 15:17:34 -06:00
trace Documentation: trace: Add documentation for TRBE 2021-04-06 16:05:38 -06:00
translations docs/zh_CN: Remove obsolete translation file 2021-05-10 15:14:31 -06:00
usb usb: gadget: u_audio: add real feedback implementation 2021-06-09 11:26:49 +02:00
userspace-api Documentation: seccomp: Fix user notification documentation 2021-05-28 09:54:12 -07:00
virt Bugfixes, including a TLB flush fix that affects processors 2021-06-09 13:09:57 -07:00
vm mm: gup: remove FOLL_SPLIT 2021-04-30 11:20:37 -07:00
w1
watchdog
x86 x86/msr: Rename MSR_K8_SYSCFG to MSR_AMD64_SYSCFG 2021-05-10 07:51:38 +02:00
xtensa
.gitignore
arch.rst
asm-annotations.rst
atomic_bitops.txt
atomic_t.txt
Changes
CodingStyle
conf.py
COPYING-logo
docutils.conf
dontdiff kbuild: generate Module.symvers only when vmlinux exists 2021-04-25 05:17:02 +09:00
index.rst
Kconfig
logo.gif
Makefile
memory-barriers.txt
SubmittingPatches
watch_queue.rst