The initial versions of the devicetree enablement patches for ehci-platform
used "ehci-platform" as compatible string. However this was disliked by various
reviewers because the platform bus is a Linux invention and devicetree is
supposed to be OS agnostic. After much discussion I gave up, added a:
"depends on !PPC_OF" to Kconfig to avoid a known conflict with PPC-OF platforms
and went with the generic usb-ehci as requested.
In retro-spect I should have chosen something different, the dts files for many
existing boards already claim to be compatible with "usb-ehci", ie they have:
compatible = "ti,ehci-omap", "usb-ehci";
In theory this should not be a problem since the "ti,ehci-omap" entry takes
presedence, but in practice using a conflicting compatible string is an issue,
because it makes which driver gets used depend on driver registration order.
This patch changes the compatible string claimed by ehci-platform to
"generic-ehci", avoiding the driver registration / module loading ordering
problems, and removes the "depends on !PPC_OF" workaround.
Signed-off-by: Hans de Goede <hdegoede@redhat.com>
Acked-by: Alan Stern <stern@rowland.harvard.edu>
Tested-by: Kevin Hilman <khilman@linaro.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
USB EHCI controllers
Required properties:
- - compatible : should be "usb-ehci".
+ - compatible : should be "generic-ehci".
- reg : should contain at least address and length of the standard EHCI
register set for the device. Optional platform-dependent registers
(debug-port or other) can be also specified here, but only after
Example (Allwinner sun4i A10 SoC):
ehci0: usb@01c14000 {
- compatible = "allwinner,sun4i-a10-ehci", "usb-ehci";
+ compatible = "allwinner,sun4i-a10-ehci", "generic-ehci";
reg = <0x01c14000 0x100>;
interrupts = <39>;
clocks = <&ahb_gates 1>;
config USB_EHCI_HCD_PLATFORM
tristate "Generic EHCI driver for a platform device"
- depends on !PPC_OF
default n
---help---
Adds an EHCI host driver for a generic platform device, which
static const struct of_device_id vt8500_ehci_ids[] = {
{ .compatible = "via,vt8500-ehci", },
{ .compatible = "wm,prizm-ehci", },
- { .compatible = "usb-ehci", },
+ { .compatible = "generic-ehci", },
{}
};
MODULE_DEVICE_TABLE(of, vt8500_ehci_ids);