phy: introduce phy_get_by_index ...

The upstream (v5.6-rc1) device tree node of the stm32mp157c-dk2's OHCI
has a phys property, but not phy-names. We have no API to reference
such a phy easily (passing NULL isn't allowed). Add one.

Signed-off-by: Ahmad Fatoum <a.fatoum@pengutronix.de>
Signed-off-by: Sascha Hauer <s.hauer@pengutronix.de>

phy: populate existing ->pwr member with phy-supply ...

barebox already enables/disables the ->pwr regulator at the correct
places, but doesn't assign a value anywhere. Initialize it with the
phy-supply regulator like Linux does.

Signed-off-by: Ahmad Fatoum <a.fatoum@pengutronix.de>
Signed-off-by: Sascha Hauer <s.hauer@pengutronix.de>

phy: remove unused init_data parameter ...

Linux has since migrated to a new lookup API that lacks the init_data
parameter. As it's unused in barebox, follow suit.

Signed-off-by: Ahmad Fatoum <a.fatoum@pengutronix.de>
Signed-off-by: Sascha Hauer <s.hauer@pengutronix.de>

phy: core: Assume EPROBE_DEFER in of_phy_provider_lookup() ...

In order to support PHY driver probe deferral change the code to
assume EPROBE_DEFER instead of ENODEV when requested PHY is missing
from phy_provider_list.

Signed-off-by: Andrey Smirnov <andrew.smirnov@gmail.com>
Signed-off-by: Sascha Hauer <s.hauer@pengutronix.de>

drivers: Introduce dev_set_name() ...

Introduce dev_set_name() in order to hide implementation details of
setting device's name so it'd be easier to change it.

Signed-off-by: Andrey Smirnov <andrew.smirnov@gmail.com>
Signed-off-by: Sascha Hauer <s.hauer@pengutronix.de>

phy: Introduce to_usbphy conversion function ...

The generic phy support layer has the necessary list handling
and phy retrieval functions, so we should reuse them for usb
phys. This adds a phy_to_usbphy() conversion function which
drivers can implement which attach to the generic phy layer
and are really usb phys.

Signed-off-by: Sascha Hauer <s.hauer@pengutronix.de>

phy: Introduce of_phy_get_by_phandle ...

Currently generic phy support assumes that the standard phy binding from
dts/Bindings/phy/phy-bindings.txt is used. This adds a helper function
which can be used to retrieve a phy when this standard binding is not
used.

Signed-off-by: Sascha Hauer <s.hauer@pengutronix.de>

add generic PHY framework ...

This brings in the generix PHY framework from Linux.
I tried to strip it down as much as possible while
keeping it useful.

Signed-off-by: Lucas Stach <dev@lynxeye.de>
Signed-off-by: Sascha Hauer <s.hauer@pengutronix.de>