Re: [PATCH v8 0/8] power: add power sequence library

From: Rafael J. Wysocki
Date: Fri Oct 14 2016 - 08:02:56 EST

On Friday, October 14, 2016 10:59:47 AM Peter Chen wrote:
> Hi all,
>
> This is a follow-up for my last power sequence framework patch set [1].
> According to Rob Herring and Ulf Hansson's comments[2]. The kinds of
> power sequence instances will be added at postcore_initcall, the match
> criteria is compatible string first, if the compatible string is not
> matched between dts and library, it will try to use generic power sequence.
>
> The host driver just needs to call of_pwrseq_on/of_pwrseq_off
> if only one power sequence instance is needed, for more power sequences
> are used, using of_pwrseq_on_list/of_pwrseq_off_list instead (eg, USB hub driver).
>
> In future, if there are special power sequence requirements, the special
> power sequence library can be created.
>
> This patch set is tested on i.mx6 sabresx evk using a dts change, I use
> two hot-plug devices to simulate this use case, the related binding
> change is updated at patch [1/6], The udoo board changes were tested
> using my last power sequence patch set.[3]
>
> Except for hard-wired MMC and USB devices, I find the USB ULPI PHY also
> need to power on itself before it can be found by ULPI bus.
>
> [1] http://www.spinics.net/lists/linux-usb/msg142755.html
> [2] http://www.spinics.net/lists/linux-usb/msg143106.html
> [3] http://www.spinics.net/lists/linux-usb/msg142815.html
>
> Changes for v8:
> - Allocate one extra pwrseq instance if pwrseq_get has succeed, it can avoid
> preallocate instances problem which the number of instance is decided at
> compile time, thanks for Heiko Stuebner's suggestion [Patch 2/8]
> - Delete pwrseq_compatible_sample.c which is the demo purpose to show compatible
> match method. [Patch 2/8]
> - Add Maciej S. Szmigiero's tested-by. [Patch 7/8]
>
> Changes for v7:
> - Create kinds of power sequence instance at postcore_initcall, and match
> the instance with node using compatible string, the beneit of this is
> the host driver doesn't need to consider which pwrseq instance needs
> to be used, and pwrseq core will match it, however, it eats some memories
> if less power sequence instances are used. [Patch 2/8]
> - Add pwrseq_compatible_sample.c to test match pwrseq using device_id. [Patch 2/8]
> - Fix the comments Vaibhav Hiremath adds for error path for clock and do not
> use device_node for parameters at pwrseq_on. [Patch 2/8]
> - Simplify the caller to use power sequence, follows Alan's commnets [Patch 4/8]
> - Tested three pwrseq instances together using both specific compatible string and
> generic libraries.
>
> Changes for v6:
> - Add Matthias Kaehlcke's Reviewed-by and Tested-by. (patch [2/6])
> - Change chipidea core of_node assignment for coming user. (patch [5/6])
> - Applies Joshua Clayton's three dts changes for two boards,
> the USB device's reg has only #address-cells, but without #size-cells.
>
> Changes for v5:
> - Delete pwrseq_register/pwrseq_unregister, which is useless currently
> - Fix the linker error when the pwrseq user is compiled as module
>
> Changes for v4:
> - Create the patch on next-20160722
> - Fix the of_node is not NULL after chipidea driver is unbinded [Patch 5/6]
> - Using more friendly wait method for reset gpio [Patch 2/6]
> - Support multiple input clocks [Patch 2/6]
> - Add Rob Herring's ack for DT changes
> - Add Joshua Clayton's Tested-by
>
> Changes for v3:
> - Delete "power-sequence" property at binding-doc, and change related code
> at both library and user code.
> - Change binding-doc example node name with Rob's comments
> - of_get_named_gpio_flags only gets the gpio, but without setting gpio flags,
> add additional code request gpio with proper gpio flags
> - Add Philipp Zabel's Ack and MAINTAINER's entry
>
> Changes for v2:
> - Delete "pwrseq" prefix and clock-names for properties at dt binding
> - Should use structure not but its pointer for kzalloc
> - Since chipidea core has no of_node, let core's of_node equals glue
> layer's at core's probe
>
> Joshua Clayton (2):
> ARM: dts: imx6qdl: Enable usb node children with <reg>
> ARM: dts: imx6q-evi: Fix onboard hub reset line
>
> Peter Chen (6):
> binding-doc: power: pwrseq-generic: add binding doc for generic power
> sequence library
> power: add power sequence library
> binding-doc: usb: usb-device: add optional properties for power
> sequence
> usb: core: add power sequence handling for USB devices
> usb: chipidea: let chipidea core device of_node equal's glue layer
> device of_node
> ARM: dts: imx6qdl-udoo.dtsi: fix onboard USB HUB property
>
> .../bindings/power/pwrseq/pwrseq-generic.txt | 48 ++++++
> .../devicetree/bindings/usb/usb-device.txt | 10 +-
> MAINTAINERS | 9 +
> arch/arm/boot/dts/imx6q-evi.dts | 25 +--
> arch/arm/boot/dts/imx6qdl-udoo.dtsi | 26 ++-
> arch/arm/boot/dts/imx6qdl.dtsi | 6 +
> drivers/power/Kconfig | 1 +
> drivers/power/Makefile | 1 +
> drivers/power/pwrseq/Kconfig | 19 ++
> drivers/power/pwrseq/Makefile | 2 +
> drivers/power/pwrseq/core.c | 191 +++++++++++++++++++++
> drivers/power/pwrseq/pwrseq_generic.c | 183 ++++++++++++++++++++
> drivers/usb/chipidea/core.c | 27 ++-
> drivers/usb/core/hub.c | 41 ++++-
> drivers/usb/core/hub.h | 1 +
> include/linux/power/pwrseq.h | 72 ++++++++
> 16 files changed, 621 insertions(+), 41 deletions(-)
> create mode 100644 Documentation/devicetree/bindings/power/pwrseq/pwrseq-generic.txt
> create mode 100644 drivers/power/pwrseq/Kconfig
> create mode 100644 drivers/power/pwrseq/Makefile
> create mode 100644 drivers/power/pwrseq/core.c
> create mode 100644 drivers/power/pwrseq/pwrseq_generic.c
> create mode 100644 include/linux/power/pwrseq.h

Meta question: Who's the maintainer you are targetting this at?

Thanks,
Rafael