On Thu, Jan 05, 2017 at 02:01:53PM +0800, Peter Chen wrote: > 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 > library to cover this requirement. The core code has supplied > some common helpers for host driver, and individual power sequence > libraries handle kinds of power sequence for devices. The pwrseq > librares always need to allocate extra instance for compatible > string match. > > pwrseq_generic is intended for general purpose of power sequence, which > handles gpios and clocks currently, and can cover other controls in > future. The host driver just needs to call of_pwrseq_on/of_pwrseq_off > if only one power sequence is needed, else call of_pwrseq_on_list > /of_pwrseq_off_list instead (eg, USB hub driver). > > For new power sequence library, it can add its compatible string > to pwrseq_of_match_table, then the pwrseq core will match it with > DT's, and choose this library at runtime. > > Signed-off-by: Peter Chen <peter.chen@xxxxxxx> > Tested-by: Maciej S. Szmigiero <mail@xxxxxxxxxxxxxxxxxxxxx> > Tested-by Joshua Clayton <stillcompiling@xxxxxxxxx> > Reviewed-by: Matthias Kaehlcke <mka@xxxxxxxxxxxx> > Tested-by: Matthias Kaehlcke <mka@xxxxxxxxxxxx> > --- > MAINTAINERS | 9 + > drivers/power/Kconfig | 1 + > drivers/power/Makefile | 1 + > drivers/power/pwrseq/Kconfig | 20 ++ > drivers/power/pwrseq/Makefile | 2 + > drivers/power/pwrseq/core.c | 335 ++++++++++++++++++++++++++++++++++ > drivers/power/pwrseq/pwrseq_generic.c | 224 +++++++++++++++++++++++ > include/linux/power/pwrseq.h | 81 ++++++++ > 8 files changed, 673 insertions(+) > 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 > Acked-by: Krzysztof Kozlowski <krzk@xxxxxxxxxx> Tested on Odroid U3 (reset sequence for LAN9730): Tested-by: Krzysztof Kozlowski <krzk@xxxxxxxxxx> Best regards, Krzysztof -- 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
