Re: [PATCH v2] of: property: fw_devlink: Add support for "phy-handle" property
From: Saravana Kannan <hidden>
Date: 2021-08-23 18:13:48
Also in:
linux-amlogic, linux-devicetree, lkml
On Mon, Aug 23, 2021 at 6:16 AM Andrew Lunn [off-list ref] wrote:
quoted hunk ↗ jump to hunk
On Mon, Aug 23, 2021 at 02:08:48PM +0200, Marek Szyprowski wrote:quoted
Hi, On 18.08.2021 04:17, Saravana Kannan wrote:quoted
Allows tracking dependencies between Ethernet PHYs and their consumers. Cc: Andrew Lunn <andrew@lunn.ch> Cc: netdev@vger.kernel.org Signed-off-by: Saravana Kannan <redacted>This patch landed recently in linux-next as commit cf4b94c8530d ("of: property: fw_devlink: Add support for "phy-handle" property"). It breaks ethernet operation on my Amlogic-based ARM64 boards: Odroid C4 (arm64/boot/dts/amlogic/meson-sm1-odroid-c4.dts) and N2 (meson-g12b-odroid-n2.dts) as well as Khadas VIM3/VIM3l (meson-g12b-a311d-khadas-vim3.dts and meson-sm1-khadas-vim3l.dts). In case of OdroidC4 I see the following entries in the /sys/kernel/debug/devices_deferred: ff64c000.mdio-multiplexer ff3f0000.ethernet Let me know if there is anything I can check to help debugging this issue.Hi Marek Please try this. Completetly untested, not even compile teseted:diff --git a/drivers/of/property.c b/drivers/of/property.c index 0c0dc2e369c0..7c4e257c0a81 100644 --- a/drivers/of/property.c +++ b/drivers/of/property.c@@ -1292,6 +1292,7 @@ DEFINE_SIMPLE_PROP(resets, "resets", "#reset-cells") DEFINE_SIMPLE_PROP(leds, "leds", NULL) DEFINE_SIMPLE_PROP(backlight, "backlight", NULL) DEFINE_SIMPLE_PROP(phy_handle, "phy-handle", NULL) +DEFINE_SIMPLE_PROP(mdio_parent_bus, "mdio-parent-bus", NULL); DEFINE_SUFFIX_PROP(regulators, "-supply", NULL) DEFINE_SUFFIX_PROP(gpio, "-gpio", "#gpio-cells")@@ -1381,6 +1382,7 @@ static const struct supplier_bindings of_supplier_bindings[] = { { .parse_prop = parse_leds, }, { .parse_prop = parse_backlight, }, { .parse_prop = parse_phy_handle, }, + { .parse_prop = parse_mdio_parent_bus, }, { .parse_prop = parse_gpio_compat, }, { .parse_prop = parse_interrupts, }, { .parse_prop = parse_regulators, },
Looking at the code, I'm fairly certain that the device that corresponds to a DT node pointed to by mdio-parent-bus will be a "bus" device that's registered with the mdio_bus_class. If my understanding is right, then Nak for this patch. It'll break a lot of probes. TL;DR is that stateful/managed device links don't make sense for devices that are never probed/bound to a driver. I plan to improve device links to try and accommodate these cases nicely, but that's in my TO DO list. Until that's completed, this patch will break stuff. -Saravana