[PATCH 4/4] ARM: dts: vf610-zii-dev-rev-b: add interrupts for 88e1545 PHY

On Thu, Dec 21, 2017 at 11:53:47PM +0100, Linus Walleij wrote:

On Thu, Dec 21, 2017 at 6:32 PM, Russell King - ARM Linux
[off-list ref] wrote:

quoted

What we have here is _really_ a shared interrupt between four
separate devices, and we need a way to sanely describe resources
shared between several device instances to pinmux.  Unfortunately,
it seems pinmux is designed around one device having exclusive use
of a resource, which makes it hard to describe shared interrupts in
DT.

Given that DT should be a description of the hardware, and should be
independent of the OS implementation, I'd say this is a pinmux bug,
because pinmux gets in the way of describing the hardware correctly.
;)

Hm that would be annoying. But when I look at it I think it would
actually work. Did you try just assigning the same pin control
state to all the PHY's and see what happens?

Just set
pinctrl-names = "default";
pinctrl-0 = <&pinctrl_mv88e1545>;

on all of them?

It was tried, DT was happy, but the kernel on boot complained because
pinctrl objected, which caused the drivers to fail to bind:

libphy: mdio: probed
vf610-pinctrl 40048000.iomuxc: pin VF610_PAD_PTB0 already requested by !mdio-mux!mdio at 4!switch at 0!mdio:00; cannot claim for !mdio-mux!mdio at 4!switch at 0!mdio:01
vf610-pinctrl 40048000.iomuxc: pin-22 (!mdio-mux!mdio at 4!switch at 0!mdio:01) status -22
vf610-pinctrl 40048000.iomuxc: could not request pin 22 (VF610_PAD_PTB0) from group pinctrl-mv88e1545  on device 40048000.iomuxc
Marvell 88E1545 !mdio-mux!mdio at 4!switch at 0!mdio:01: Error applying setting, reverse things back
Marvell 88E1545: probe of !mdio-mux!mdio at 4!switch at 0!mdio:01 failed with error -22
vf610-pinctrl 40048000.iomuxc: pin VF610_PAD_PTB0 already requested by !mdio-mux!mdio at 4!switch at 0!mdio:00; cannot claim for !mdio-mux!mdio at 4!switch at 0!mdio:02
vf610-pinctrl 40048000.iomuxc: pin-22 (!mdio-mux!mdio at 4!switch at 0!mdio:02) status -22
vf610-pinctrl 40048000.iomuxc: could not request pin 22 (VF610_PAD_PTB0) from group pinctrl-mv88e1545  on device 40048000.iomuxc
Marvell 88E1545 !mdio-mux!mdio at 4!switch at 0!mdio:02: Error applying setting, reverse things back
Marvell 88E1545: probe of !mdio-mux!mdio at 4!switch at 0!mdio:02 failed with error -22

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