Groups | Search | Server Info | Keyboard shortcuts | Login | Register [http] [https] [nntp] [nntps]


Groups > linux.kernel > #1411451

Re: [PATCH v3 09/12] EXAMPLE CODE: usb: port: Parse pwrseq phandle from Device Tree

From Stephen Boyd <stephen.boyd@linaro.org>
Newsgroups linux.kernel
Subject Re: [PATCH v3 09/12] EXAMPLE CODE: usb: port: Parse pwrseq phandle from Device Tree
Date 2016-06-01 20:20 +0200
Message-ID <rFiUi-3wl-19@gated-at.bofh.it> (permalink)
References <rF9nX-5Ug-7@gated-at.bofh.it> <rF9nX-5Ug-15@gated-at.bofh.it> <rFaan-6aY-43@gated-at.bofh.it> <rFdhT-8iE-9@gated-at.bofh.it>
Organization linux.* mail to news gateway

Show all headers | View raw


Quoting Peter Chen (2016-06-01 05:05:20)
> On Wed, Jun 01, 2016 at 01:57:23AM -0700, Stephen Boyd wrote:
> > Quoting Krzysztof Kozlowski (2016-06-01 01:02:18)
> > > Parse usb-pwrseq property from Device Tree to get the phandle to pwrseq
> > > device.  The pwrseq device will be used by USB hub to cycle the power
> > > before activating ports.
> > > 
> > > Signed-off-by: Krzysztof Kozlowski <k.kozlowski@samsung.com>
> > 
> > Drive by review comment.
> > 
> > I was hoping this would help me with a problem I'm having where I have a
> > hub (smsc4604) that needs to be taken out of reset before my HSIC
> > controller sends a USB reset to it, but it seems this is more about
> > doing some sort of power on sequence after enumeration?
> > 
> 
> No, you may need to do reset before enumeration, the general purpose of
> reset is eliminate unstable hardware state, and let the controller find
> the device.
> 
> Try to do it at bootloader to see if it works for you.
> 

Sorry the bootloader doesn't do this so that doesn't work for me.

Back to linux.kernel | Previous | NextPrevious in thread | Next in thread | Find similar | Unroll thread


Thread

[PATCH v3 09/12] EXAMPLE CODE: usb: port: Parse pwrseq phandle from  Device Tree Krzysztof Kozlowski <k.kozlowski@samsung.com> - 2016-06-01 10:10 +0200
  Re: [PATCH v3 09/12] EXAMPLE CODE: usb: port: Parse pwrseq phandle from  Device Tree Stephen Boyd <stephen.boyd@linaro.org> - 2016-06-01 11:00 +0200
    Re: [PATCH v3 09/12] EXAMPLE CODE: usb: port: Parse pwrseq phandle  from Device Tree Krzysztof Kozlowski <k.kozlowski@samsung.com> - 2016-06-01 11:10 +0200
    Re: [PATCH v3 09/12] EXAMPLE CODE: usb: port: Parse pwrseq phandle  from Device Tree Peter Chen <hzpeterchen@gmail.com> - 2016-06-01 14:20 +0200
      Re: [PATCH v3 09/12] EXAMPLE CODE: usb: port: Parse pwrseq phandle from  Device Tree Stephen Boyd <stephen.boyd@linaro.org> - 2016-06-01 20:20 +0200
        Re: [PATCH v3 09/12] EXAMPLE CODE: usb: port: Parse pwrseq phandle  from Device Tree Peter Chen <hzpeterchen@gmail.com> - 2016-06-02 03:40 +0200

csiph-web