Commit 705c333a authored by Mathias Nyman's avatar Mathias Nyman Committed by Greg Kroah-Hartman
Browse files

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



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: default avatarMathias Nyman <mathias.nyman@linux.intel.com>
Link: https://lore.kernel.org/r/20221130091944.2171610-4-mathias.nyman@linux.intel.com


Signed-off-by: default avatarGreg Kroah-Hartman <gregkh@linuxfoundation.org>
parent fed70b61

drivers/usb/host/xhci-hub.c

+18 −4
Original line number Diff line number Diff line
@@ -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