On Fri, Dec 02, 2016 at 01:06:47AM -0800, Matt Ranostay wrote: > On Fri, Dec 2, 2016 at 12:28 AM, Ulf Hansson <ulf.hansson@xxxxxxxxxx> wrote: > > On 2 December 2016 at 08:22, Matt Ranostay <matt@ranostay.consulting> wrote: > >> > >> > >>> On Dec 1, 2016, at 23:13, Ulf Hansson <ulf.hansson@xxxxxxxxxx> wrote: > >>> > >>>> On 2 December 2016 at 07:17, Matt Ranostay <matt@ranostay.consulting> wrote: > >>>> Add optional device-post-power-on parameters to disable post_power_on > >>>> function from being called since this breaks some device. > >>>> > >>>> Cc: Tony Lindgren <tony@xxxxxxxxxxx> > >>>> Cc: Ulf Hansson <ulf.hansson@xxxxxxxxxx> > >>>> Signed-off-by: Matt Ranostay <matt@ranostay.consulting> > >>>> --- > >>>> Documentation/devicetree/bindings/mmc/mmc-pwrseq-simple.txt | 2 ++ > >>>> drivers/mmc/core/pwrseq_simple.c | 7 +++++++ > >>>> 2 files changed, 9 insertions(+) > >>>> > >>>> diff --git a/Documentation/devicetree/bindings/mmc/mmc-pwrseq-simple.txt b/Documentation/devicetree/bindings/mmc/mmc-pwrseq-simple.txt > >>>> index bea306d772d1..09fa153f743e 100644 > >>>> --- a/Documentation/devicetree/bindings/mmc/mmc-pwrseq-simple.txt > >>>> +++ b/Documentation/devicetree/bindings/mmc/mmc-pwrseq-simple.txt > >>>> @@ -24,6 +24,8 @@ Optional properties: > >>>> de-asserting the reset-gpios (if any) > >>>> - invert-off-state: Invert the power down state for the reset-gpios (if any) > >>>> and pwrdn-gpios (if any) > >>>> +- disable-post-power-on : Avoid post_power_on function from being called since > >>>> + this breaks some devices > >>> > >>> This is a bit weird. I would like to avoid this, if possible. > >>> > >>> Perhaps if you simply describe the sequence in detail for your device > >>> we can figure out the best option together. > >> > >> Yeah I know it is a bit weird but we need to keep that reset pin high for at least some time after pre power on. So any case it would be another property > > > > This went offlist, please resend. > > > > Moreover, please try to describe the sequence you need in detail > > according to your HW spec. > > > > Yeah oops.... > > So basically we need to drive the reset and powerdown lines high with > a 300 milliseconds delay between both... > can't have the reset line low with post power on (pretty sure but > would need a delay anyway), and we need both reset + powerdown line > set low on powerdown. > > So the power down sequence would need to be reversed for this > application in pwrseq-simple. This sounds like you need a device specific sequence to me. Otherwise, write a language to describe any power control waveforms rather than trying to bolt on more and more properties. (Don't really go write a language.) Rob -- To unsubscribe from this list: send the line "unsubscribe linux-mmc" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
