On Thu, Sep 24, 2015 at 11:18:01AM -0500, Rob Herring wrote: > On Thu, Sep 24, 2015 at 4:26 AM, Subbaraya Sundeep Bhatta > <subbaraya.sundeep.bhatta@xxxxxxxxxx> wrote: > > Hi Peter, > > > >> -----Original Message----- > >> From: Peter Chen [mailto:peter.chen@xxxxxxxxxxxxx] > >> Sent: Thursday, September 24, 2015 2:41 PM > >> To: Subbaraya Sundeep Bhatta > >> Cc: balbi@xxxxxx; devicetree@xxxxxxxxxxxxxxx; kishon@xxxxxx; > >> gregkh@xxxxxxxxxxxxxxxxxxx; linux-usb@xxxxxxxxxxxxxxx; linux- > >> kernel@xxxxxxxxxxxxxxx; Punnaiah Choudary Kalluri; Subbaraya Sundeep Bhatta; > >> linux-arm-kernel@xxxxxxxxxxxxxxxxxxx > >> Subject: Re: [RFC PATCH 1/2] usb: doc: Add bindings for ULPI platform driver > >> > >> On Wed, Sep 23, 2015 at 06:24:01PM +0530, Subbaraya Sundeep Bhatta > >> wrote: > >> > This patch adds binding doc info for generic ULPI PHYs platform > >> > driver. > >> > > >> > Signed-off-by: Subbaraya Sundeep Bhatta <sbhatta@xxxxxxxxxx> > >> > --- > >> > .../devicetree/bindings/usb/ulpi-platform-phy.txt | 34 > >> ++++++++++++++++++++ > >> > 1 files changed, 34 insertions(+), 0 deletions(-) create mode 100644 > >> > Documentation/devicetree/bindings/usb/ulpi-platform-phy.txt > >> > > >> > diff --git > >> > a/Documentation/devicetree/bindings/usb/ulpi-platform-phy.txt > >> > b/Documentation/devicetree/bindings/usb/ulpi-platform-phy.txt > >> > new file mode 100644 > >> > index 0000000..7b8cbb4 > >> > --- /dev/null > >> > +++ b/Documentation/devicetree/bindings/usb/ulpi-platform-phy.txt > >> > @@ -0,0 +1,34 @@ > >> > +Platform driver for generic ULPI PHYs > >> > + > >> > +Required properties: > >> > +- compatible : Should be "ulpi-phy" > >> > +- reg : Physical base address and size of the USB > >> > + controller registers map to which this PHY > >> > + is connected. > >> > +- view-port : Should contain viewport register offset of the > >> > + USB controller to which this PHY is connected Optional > >> > +properties: > >> > +- drv-vbus : required if turning VBUS on/off has to be driven > >> > + by writing to PHY. This feature depends on board > >> > + design. > >> > + > >> > +Example: > >> > +Below example shows the PHY binding for Chipidea USB controller which > >> > +has ulpi viewport register at 0x0170 > >> > + > >> > + usb_phy0: phy0 { > >> > + compatible = "ulpi-phy"; > >> > + reg = <0xe0002000 0x1000>; > >> > + view-port = <0x0170>; > >> > + drv-vbus; > >> > + }; > >> > + > >> > + usb0: usb@e0002000 { > >> > + compatible = "chipidea,usb2"; > >> > + interrupt-parent = <&intc>; > >> > + interrupts = <0 21 4>; > >> > + reg = <0xe0002000 0x1000>; > >> > >> Although just call devm_ioremap twice for the same register region does not > >> cause any errors, I am not sure if it will has other potential problems. Cc: arm > >> list. > > > > Yes Peter I was also in doubt to call devm_ioremap twice for same register region. > > devm_ioremap_resource complained hence modified to devm_ioremap. Thanks for > > adding arm-list. > > Don't put overlapping resources in the DT. Having 2 drivers accessing > the same registers is not a clean or safe design. thanks, saves me the trouble of saying the same thing. Bottom line, if devm_ioremap_resource() fails, you're wrong. Just fix your driver and move on. -- balbi
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