xhci: save slot ID in struct 'xhci_port'

Slot ID is a index of a virtual device in struct 'xhci_hcd->devs[]'.
Previously, to get the slot ID associated with a port, we had to loop
through all devices and compare ports, which is very inefficient.
Instead, the slot ID (of the device which is directly connected to the
port), is added to the its corresponding 'xhci_port' struct. As a result,
finding the port's device is quick and easy.

Function 'xhci_find_slot_id_by_port()' is removed, as it is no longer
needed.

Signed-off-by: Niklas Neronin <niklas.neronin@intel.com>
Signed-off-by: Mathias Nyman <mathias.nyman@linux.intel.com>
Link: https://lore.kernel.org/r/20240229141438.619372-4-mathias.nyman@linux.intel.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

1 files changed, 11 insertions, 60 deletions

diff --git a/drivers/usb/host/xhci-hub.c b/drivers/usb/host/xhci-hub.c
index 37128a777a58..61f083de6e19 100644
--- a/drivers/usb/host/xhci-hub.c
+++ b/drivers/usb/host/xhci-hub.c
@@ -448,40 +448,6 @@ u32 xhci_port_state_to_neutral(u32 state)
 }
 EXPORT_SYMBOL_GPL(xhci_port_state_to_neutral);
 
-/**
- * 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)
-{
-	int slot_id;
-	int i;
-	enum usb_device_speed speed;
-
-	/* 'hcd_portnum' is zero-based, thus convert one-based 'port' to zero-based */
-	port -= 1;
-	slot_id = 0;
-	for (i = 0; i < MAX_HC_SLOTS; i++) {
-		if (!xhci->devs[i] || !xhci->devs[i]->udev)
-			continue;
-		speed = xhci->devs[i]->udev->speed;
-		if (((speed >= USB_SPEED_SUPER) == (hcd->speed >= HCD_USB3))
-				&& xhci->devs[i]->rhub_port->hcd_portnum == port) {
-			slot_id = i;
-			break;
-		}
-	}
-
-	return slot_id;
-}
-EXPORT_SYMBOL_GPL(xhci_find_slot_id_by_port);
-
 /*
  * Stop device
  * It issues stop endpoint command for EP 0 to 30. And wait the last command
@@ -932,7 +898,6 @@ static int xhci_handle_usb2_port_link_resume(struct xhci_port *port,
 	struct xhci_bus_state *bus_state;
 	struct xhci_hcd	*xhci;
 	struct usb_hcd *hcd;
-	int slot_id;
 	u32 wIndex;
 
 	hcd = port->rhub->hcd;
@@ -988,13 +953,11 @@ static int xhci_handle_usb2_port_link_resume(struct xhci_port *port,
 		spin_lock_irqsave(&xhci->lock, *flags);
 
 		if (time_left) {
-			slot_id = xhci_find_slot_id_by_port(hcd, xhci,
-							    wIndex + 1);
-			if (!slot_id) {
+			if (!port->slot_id) {
 				xhci_dbg(xhci, "slot_id is zero\n");
 				return -ENODEV;
 			}
-			xhci_ring_device(xhci, slot_id);
+			xhci_ring_device(xhci, port->slot_id);
 		} else {
 			int port_status = readl(port->addr);
 
@@ -1204,7 +1167,6 @@ int xhci_hub_control(struct usb_hcd *hcd, u16 typeReq, u16 wValue,
 	unsigned long flags;
 	u32 temp, status;
 	int retval = 0;
-	int slot_id;
 	struct xhci_bus_state *bus_state;
 	u16 link_state = 0;
 	u16 wake_mask = 0;
@@ -1334,15 +1296,13 @@ int xhci_hub_control(struct usb_hcd *hcd, u16 typeReq, u16 wValue,
 				goto error;
 			}
 
-			slot_id = xhci_find_slot_id_by_port(hcd, xhci,
-							    portnum1);
-			if (!slot_id) {
+			if (!port->slot_id) {
 				xhci_warn(xhci, "slot_id is zero\n");
 				goto error;
 			}
 			/* unlock to execute stop endpoint commands */
 			spin_unlock_irqrestore(&xhci->lock, flags);
-			xhci_stop_device(xhci, slot_id, 1);
+			xhci_stop_device(xhci, port->slot_id, 1);
 			spin_lock_irqsave(&xhci->lock, flags);
 
 			xhci_set_link_state(xhci, port, XDEV_U3);
@@ -1465,14 +1425,12 @@ int xhci_hub_control(struct usb_hcd *hcd, u16 typeReq, u16 wValue,
 
 			if (link_state == USB_SS_PORT_LS_U3) {
 				int retries = 16;
-				slot_id = xhci_find_slot_id_by_port(hcd, xhci,
-								    portnum1);
-				if (slot_id) {
+				if (port->slot_id) {
 					/* unlock to execute stop endpoint
 					 * commands */
 					spin_unlock_irqrestore(&xhci->lock,
 								flags);
-					xhci_stop_device(xhci, slot_id, 1);
+					xhci_stop_device(xhci, port->slot_id, 1);
 					spin_lock_irqsave(&xhci->lock, flags);
 				}
 				xhci_set_link_state(xhci, port, USB_SS_PORT_LS_U3);
@@ -1586,13 +1544,11 @@ int xhci_hub_control(struct usb_hcd *hcd, u16 typeReq, u16 wValue,
 			}
 			bus_state->port_c_suspend |= 1 << wIndex;
 
-			slot_id = xhci_find_slot_id_by_port(hcd, xhci,
-					portnum1);
-			if (!slot_id) {
+			if (!port->slot_id) {
 				xhci_dbg(xhci, "slot_id is zero\n");
 				goto error;
 			}
-			xhci_ring_device(xhci, slot_id);
+			xhci_ring_device(xhci, port->slot_id);
 			break;
 		case USB_PORT_FEAT_C_SUSPEND:
 			bus_state->port_c_suspend &= ~(1 << wIndex);
@@ -1823,10 +1779,7 @@ retry:
 		if (!portsc_buf[port_index])
 			continue;
 		if (test_bit(port_index, &bus_state->bus_suspended)) {
-			int slot_id;
-
-			slot_id = xhci_find_slot_id_by_port(hcd, xhci,
-							    port_index + 1);
+			int slot_id = ports[port_index]->slot_id;
 			if (slot_id) {
 				spin_unlock_irqrestore(&xhci->lock, flags);
 				xhci_stop_device(xhci, slot_id, 1);
@@ -1879,7 +1832,6 @@ int xhci_bus_resume(struct usb_hcd *hcd)
 	struct xhci_bus_state *bus_state;
 	unsigned long flags;
 	int max_ports, port_index;
-	int slot_id;
 	int sret;
 	u32 next_state;
 	u32 temp, portsc;
@@ -1972,9 +1924,8 @@ int xhci_bus_resume(struct usb_hcd *hcd)
 			continue;
 		}
 		xhci_test_and_clear_bit(xhci, ports[port_index], PORT_PLC);
-		slot_id = xhci_find_slot_id_by_port(hcd, xhci, port_index + 1);
-		if (slot_id)
-			xhci_ring_device(xhci, slot_id);
+		if (ports[port_index]->slot_id)
+			xhci_ring_device(xhci, ports[port_index]->slot_id);
 	}
 	(void) readl(&xhci->op_regs->command);