Am 04.12.18 um 09:52 schrieb Uwe Kleine-König: > Hello Stefan, > > On Tue, Dec 04, 2018 at 09:40:26AM +0100, Stefan Wahren wrote: >> Am 04.12.18 um 09:31 schrieb Uwe Kleine-König: >>> The status quo on i.MX6 is that if "over-current-active-high" is >>> specified in the device tree this is configured as expected. If >>> the property is missing polarity isn't changed and so the >>> polarity is kept as setup by the bootloader. Reset default is >>> active high, so active low can only be used with help by the >>> bootloader. On i.MX7 it is similar, but there disabling of >>> over current detection has a similar inconsistency. >>> >>> This patch introduces a new property that allows to explicitly >>> configure for active low over current detection and consistently >>> sets this up. In the absence of an explicit configuration the >>> bit is kept as is. On i.MX7 over current detection is used unless >>> disabled in the device tree. >>> >>> Signed-off-by: Uwe Kleine-König <u.kleine-koenig@xxxxxxxxxxxxxx> >>> --- >>> .../devicetree/bindings/usb/ci-hdrc-usb2.txt | 5 ++-- >>> drivers/usb/chipidea/ci_hdrc_imx.c | 16 ++++++++--- >>> drivers/usb/chipidea/ci_hdrc_imx.h | 8 +++++- >>> drivers/usb/chipidea/usbmisc_imx.c | 28 ++++++++++++++----- >>> 4 files changed, 43 insertions(+), 14 deletions(-) >>> >>> diff --git a/Documentation/devicetree/bindings/usb/ci-hdrc-usb2.txt b/Documentation/devicetree/bindings/usb/ci-hdrc-usb2.txt >>> index 529e51879fb2..c32f6e983cf6 100644 >>> --- a/Documentation/devicetree/bindings/usb/ci-hdrc-usb2.txt >>> +++ b/Documentation/devicetree/bindings/usb/ci-hdrc-usb2.txt >>> @@ -87,8 +87,9 @@ i.mx specific properties >>> - fsl,usbmisc: phandler of non-core register device, with one >>> argument that indicate usb controller index >>> - disable-over-current: disable over current detect >>> -- over-current-active-high: over current signal polarity is high active, >>> - typically over current signal polarity is low active. >>> +- over-current-active-low: over current signal polarity is active low. >>> +- over-current-active-high: over current signal polarity is active high. >>> + It's recommended to specify the over current polarity. >>> - external-vbus-divider: enables off-chip resistor divider for Vbus >>> >>> Example: >> thanks for making this configurable. But shouldn't this be a separate >> patch and reviewed by the devicetree guys? > I'm not sure about the separate patch part. My impression is it depends > on the maintainer if a change to the binding (opposed to the > introduction of a binding) should be separate or not. > > But for the review you are right, I added the dt people to Cc for them > to comment. In v2 Matthew also noted that he would prefer to handle the > situation when both over-current-active-low and over-current-active-high > were given differently. I think we don't need that as this is a case of > "broken dt" and it doesn't matter much what is done then. (With my patch > we're configuring for active high in that case.) A feedback here would > be great, too. AFAIR such invalid settings should be catched with a proper error message and abort of the probing. Regards Stefan > > Best regards > Uwe >
