Hi all, We have an well-known problem that the device needs to do some power sequence before it can be recognized by related host, the typical example like hard-wired mmc devices and usb devices. This power sequence is hard to be described at device tree and handled by related host driver, so we have created a common power sequence framework to handle this requirement. The generic code is supplied some common helpers from host driver, and individual power sequence driver handles kinds of power sequence for devices. Since the MMC has already done the similar things, and this power sequence handling can be generic, we use mmc power sequence code as base to create this framework. This patch set is based on Krzysztof Kozlowski's RFC patch set (v4.7-rc1) [1], and making some changes which can let it be generic. After that, we create a generic power sequence driver for USB devices which handles below things, it includes all input signals for devices I can consider. - Clock and its frequencies - GPIO for reset and the duration time - GPIO for enable - Regulator for power 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 udoo board changes were tested using my last power sequence patch set. [2] @Maciej S. Szmigiero, Oscar, would you please test them on imx6qdl udoo boards? @Krzysztof Kozlowski, I have not written changes for your case since I find the other sequences have already at drivers/usb/misc/usb3503.c, this driver should be the place for your power sequence, I am not sure if enable regualator at usb core is suitable for you or not. @others, it is better you can help test this patch set for MMC devices and your USB devices with dts changes. Thank you for your time! [1] http://www.spinics.net/lists/linux-usb/msg142351.html [2] http://lists.infradead.org/pipermail/linux-arm-kernel/2016-March/413580.html Krzysztof Kozlowski (5): 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 Peter Chen (7): power: pwrseq: change common helpers as generic power: pwrseq: rename file name for generic driver doc: binding: pwrseq-usb-generic: add binding doc for generic usb power sequence driver power: pwrseq: pwrseq_usb_generic: add generic power sequence support for USB deivces usb: core: add power sequence handling for USB devices usb: chipidea: host: let the hcd know's parent device node ARM: dts: imx6qdl-udoo.dtsi: fix onboard USB HUB property .../{mmc => power/pwrseq}/mmc-pwrseq-simple.txt | 0 .../pwrseq/pwrseq-emmc.txt} | 0 .../bindings/power/pwrseq/pwrseq-usb-generic.txt | 31 ++++ .../devicetree/bindings/usb/usb-device.txt | 2 + MAINTAINERS | 9 + arch/arm/boot/dts/imx6qdl-udoo.dtsi | 30 +-- drivers/mmc/Kconfig | 2 - drivers/mmc/core/Kconfig | 24 --- drivers/mmc/core/Makefile | 3 - drivers/mmc/core/core.c | 8 +- drivers/mmc/core/host.c | 10 +- drivers/mmc/core/pwrseq.h | 52 ------ drivers/power/Kconfig | 1 + drivers/power/Makefile | 1 + drivers/power/pwrseq/Kconfig | 43 +++++ drivers/power/pwrseq/Makefile | 4 + drivers/{mmc/core/pwrseq.c => power/pwrseq/core.c} | 71 ++++---- drivers/{mmc/core => power/pwrseq}/pwrseq_emmc.c | 17 +- .../pwrseq/pwrseq_mmc_simple.c} | 33 ++-- drivers/power/pwrseq/pwrseq_usb_generic.c | 202 +++++++++++++++++++++ drivers/usb/chipidea/host.c | 18 +- drivers/usb/core/hub.c | 73 +++++++- drivers/usb/core/hub.h | 1 + include/linux/mmc/host.h | 4 +- include/linux/pwrseq.h | 61 +++++++ 25 files changed, 527 insertions(+), 173 deletions(-) rename Documentation/devicetree/bindings/{mmc => power/pwrseq}/mmc-pwrseq-simple.txt (100%) rename Documentation/devicetree/bindings/{mmc/mmc-pwrseq-emmc.txt => power/pwrseq/pwrseq-emmc.txt} (100%) create mode 100644 Documentation/devicetree/bindings/power/pwrseq/pwrseq-usb-generic.txt delete mode 100644 drivers/mmc/core/Kconfig delete mode 100644 drivers/mmc/core/pwrseq.h create mode 100644 drivers/power/pwrseq/Kconfig create mode 100644 drivers/power/pwrseq/Makefile rename drivers/{mmc/core/pwrseq.c => power/pwrseq/core.c} (51%) rename drivers/{mmc/core => power/pwrseq}/pwrseq_emmc.c (88%) rename drivers/{mmc/core/pwrseq_simple.c => power/pwrseq/pwrseq_mmc_simple.c} (81%) create mode 100644 drivers/power/pwrseq/pwrseq_usb_generic.c create mode 100644 include/linux/pwrseq.h -- 1.9.1 -- To unsubscribe from this list: send the line "unsubscribe devicetree" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
