Hi,
Am Mittwoch, 1. Juni 2016, 10:02:09 schrieb Krzysztof Kozlowski:
> My third approach for a USB power sequence which fixes usb3503+lan
> on Odroid U3 board if it was initialized by bootloader
> (e.g. for TFTP boot).
I was just tackling a similar bringup problem regarding an embedded usb hub
and usb-sata bridge and stumbled upon this series.
While on my (rockchip-)boards it's always "just" a reset pin that needs
handling, this series looks like it would solve exactly that problem in a very
nice way.
So while I cannot provide any meaningful insight right now, it would be cool
if you could keep me in the loop, as I'm really looking forward to this series
progressing.
Thanks
Heiko
> Changes since v2
> ================
> 1. Add Javier's reviewed-by tags. Address some comments.
> 2. Re-use existing properties for GPIOs etc by pwrseq-simple
> driver. New property is still added: "power-sequence".
> I tried to address and do according to Rob's comments.
>
> Please look at patch 6/12 ("power: pwrseq: simple: Add support
> for regulator and generic property") for bindings and the
> new code around matching "power-sequence" property.
>
> 3. I marked the usb code as "EXAMPLE" because that part
> is left to Peter Chen.
>
>
> Problem
> =======
> When Odroid U3 (usb3503 + smsc95xx + max77686) boots from network (TFTP),
> the usb3503 and LAN smsc95xx do not show up in "lsusb". Hard-reset
> is required, e.g. by suspend to RAM. The actual TFTP boot does
> not have to happen. Just "usb start" from U-Boot is sufficient.
>
> From the schematics, the regulator is a supply only to LAN, however
> without toggling it off/on, the usb3503 hub won appear neither.
>
>
> Solution
> ========
> This is very similar to the MMC pwrseq behavior so the idea is to:
> 1. Move MMC pwrseq drivers to generic place,
> 2. Extend the pwrseq-simple with regulator toggling,
> 3. Add support to USB hub and port core for pwrseq,
> 4. Toggle the regulator when needed.
>
> Best regards,
> Krzysztof
>
> Krzysztof Kozlowski (12):
> power/mmc: Move pwrseq drivers to power/pwrseq
> MAINTAINERS: Retain Ulf Hansson as the same maintainer of pwrseq
> power: pwrseq: Enable COMPILE_TEST for drivers
> power: pwrseq: Remove mmc prefix from mmc_pwrseq
> power: pwrseq: Generalize mmc_pwrseq operations by removing mmc prefix
> power: pwrseq: simple: Add support for regulator and generic property
> power: pwrseq: Add support for USB hubs with external power
> usb: hub: Handle deferred probe
> EXAMPLE CODE: usb: port: Parse pwrseq phandle from Device Tree
> EXAMPLE CODE: usb: hub: Power sequence the ports on activation
> ARM: dts: exynos: Switch the buck8 to GPIO mode on Odroid U3
> ARM: dts: exynos: Fix LAN and HUB after bootloader initialization on
> Odroid U3
>
> .../pwrseq/pwrseq-emmc.txt} | 0
> .../pwrseq/pwrseq-simple.txt} | 29 +++-
> MAINTAINERS | 9 ++
> arch/arm/boot/dts/exynos4412-odroidu3.dts | 5 +
> drivers/mmc/Kconfig | 2 -
> drivers/mmc/core/Makefile | 3 -
> drivers/mmc/core/core.c | 8 +-
> drivers/mmc/core/host.c | 2 +-
> drivers/mmc/core/pwrseq.c | 110 ---------------
> drivers/mmc/core/pwrseq.h | 52 -------
> drivers/power/Kconfig | 1 +
> drivers/power/Makefile | 1 +
> drivers/{mmc/core => power/pwrseq}/Kconfig | 22 ++-
> drivers/power/pwrseq/Makefile | 3 +
> drivers/power/pwrseq/pwrseq.c | 153
> +++++++++++++++++++++ drivers/{mmc/core => power/pwrseq}/pwrseq_emmc.c |
> 17 +--
> drivers/{mmc/core => power/pwrseq}/pwrseq_simple.c | 110 ++++++++++++---
> drivers/usb/core/hub.c | 16 ++-
> drivers/usb/core/hub.h | 3 +
> drivers/usb/core/port.c | 15 ++
> include/linux/mmc/host.h | 4 +-
> include/linux/pwrseq.h | 63 +++++++++
> 22 files changed, 414 insertions(+), 214 deletions(-)
> rename Documentation/devicetree/bindings/{mmc/mmc-pwrseq-emmc.txt =>
> power/pwrseq/pwrseq-emmc.txt} (100%) rename
> Documentation/devicetree/bindings/{mmc/mmc-pwrseq-simple.txt =>
> power/pwrseq/pwrseq-simple.txt} (53%) delete mode 100644
> drivers/mmc/core/pwrseq.c
> delete mode 100644 drivers/mmc/core/pwrseq.h
> rename drivers/{mmc/core => power/pwrseq}/Kconfig (60%)
> create mode 100644 drivers/power/pwrseq/Makefile
> create mode 100644 drivers/power/pwrseq/pwrseq.c
> rename drivers/{mmc/core => power/pwrseq}/pwrseq_emmc.c (88%)
> rename drivers/{mmc/core => power/pwrseq}/pwrseq_simple.c (52%)
> create mode 100644 include/linux/pwrseq.h
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