Re: [PATCH] of_mdio: Fix broken PHY IRQ in case of probe deferral

David Miller
2017-05-18T15:21:49Z

From: Geert Uytterhoeven <geert+renesas@glider.be>
Date: Thu, 18 May 2017 14:59:05 +0200

> If an Ethernet PHY is initialized before the interrupt controller it is
> connected to, a message like the following is printed:
>
> irq: no irq domain found for /interrupt-controller@e61c0000 !
>
> However, the actual error is ignored, leading to a non-functional (-1)
> PHY interrupt later:
>
> Micrel KSZ8041RNLI ee700000.ethernet-ffffffff:01: attached PHY driver [Micrel KSZ8041RNLI] (mii_bus:phy_addr=ee700000.ethernet-ffffffff:01, irq=-1)
>
> Depending on whether the PHY driver will fall back to polling, Ethernet
> may or may not work.
>
> To fix this:
> 1. Switch of_mdiobus_register_phy() from irq_of_parse_and_map() to
> of_irq_get().
> Unlike the former, the latter returns -EPROBE_DEFER if the
> interrupt controller is not yet available, so this condition can be
> detected.
> Other errors are handled the same as before, i.e. use the passed
> mdio->irq[addr] as interrupt.
> 2. Propagate and handle errors from of_mdiobus_register_phy() and
> of_mdiobus_register_device().
>
> Signed-off-by: Geert Uytterhoeven <geert+renesas@glider.be>

Florian or someone similarly knowledgable, please review.