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
[off-list ref] wrote:

quoted

Hi Peter,

quoted

-----Original Message-----
From: Peter Chen [mailto:peter.chen at freescale.com]
Sent: Thursday, September 24, 2015 2:41 PM
To: Subbaraya Sundeep Bhatta
Cc: balbi at ti.com; devicetree at vger.kernel.org; kishon at ti.com;
gregkh at linuxfoundation.org; linux-usb at vger.kernel.org; linux-
kernel at vger.kernel.org; Punnaiah Choudary Kalluri; Subbaraya Sundeep Bhatta;
linux-arm-kernel at lists.infradead.org
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:

quoted

This patch adds binding doc info for generic ULPI PHYs platform
driver.

Signed-off-by: Subbaraya Sundeep Bhatta <redacted>
---
 .../devicetree/bindings/usb/ulpi-platform-phy.txt  |   34

++++++++++++++++++++

quoted

 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 at 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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