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xhci: export two xhci_hub functions for xhci-pci module usage

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some Intel Alder Lake xHC hosts on ChromeOS platforms need special
workarounds touching port registers at xHC pci host hibernate.

Export xhci_port_state_to_neutral() and xhci_find_slot_id_by_port()
so they can be called from xhci-pci.c and thus the xhci-pci module.

Signed-off-by: Mathias Nyman <mathias.nyman@linux.intel.com>
Link: https://lore.kernel.org/r/20221130091944.2171610-4-mathias.nyman@linux.intel.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
This commit is contained in:
Mathias Nyman 2022-11-30 11:19:41 +02:00 committed by Greg Kroah-Hartman
parent fed70b61ef
commit 705c333a7a
1 changed files with 18 additions and 4 deletions
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22
drivers/usb/host/xhci-hub.c
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@ -426,24 +426,37 @@ static unsigned int xhci_port_speed(unsigned int port_status)
*/
#define XHCI_PORT_RZ ((1<<2) | (1<<24) | (0xf<<28))
/*
/**
* xhci_port_state_to_neutral() - Clean up read portsc value back into writeable
* @state: u32 port value read from portsc register to be cleanup up
*
* Given a port state, this function returns a value that would result in the
* port being in the same state, if the value was written to the port status
* control register.
* Save Read Only (RO) bits and save read/write bits where
* writing a 0 clears the bit and writing a 1 sets the bit (RWS).
* For all other types (RW1S, RW1CS, RW, and RZ), writing a '0' has no effect.
*
* Return: u32 value that can be written back to portsc register without
* changing port state.
*/
u32 xhci_port_state_to_neutral(u32 state)
{
/* Save read-only status and port state */
return (state & XHCI_PORT_RO) | (state & XHCI_PORT_RWS);
}
EXPORT_SYMBOL_GPL(xhci_port_state_to_neutral);
/*
* find slot id based on port number.
* @port: The one-based port number from one of the two split roothubs.
/**
* xhci_find_slot_id_by_port() - Find slot id of a usb device on a roothub port
* @hcd: pointer to hcd of the roothub
* @xhci: pointer to xhci structure
* @port: one-based port number of the port in this roothub.
*
* Return: Slot id of the usb device connected to the root port, 0 if not found
*/
int xhci_find_slot_id_by_port(struct usb_hcd *hcd, struct xhci_hcd *xhci,
u16 port)
{
@ -465,6 +478,7 @@ int xhci_find_slot_id_by_port(struct usb_hcd *hcd, struct xhci_hcd *xhci,
return slot_id;
}
EXPORT_SYMBOL_GPL(xhci_find_slot_id_by_port);
/*
* Stop device