usb: xhci: split core allocation and initialization

Separate allocation and initialization in the xHCI core:
* xhci_mem_init() now only handles memory allocation.
* xhci_init() now only handles initialization.

This split allows xhci_init() to be reused when resuming from S4
suspend-to-disk.

Signed-off-by: Niklas Neronin <niklas.neronin@linux.intel.com>
Signed-off-by: Mathias Nyman <mathias.nyman@linux.intel.com>
Link: https://patch.msgid.link/20260402131342.2628648-11-mathias.nyman@linux.intel.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

2 files changed, 13 insertions, 20 deletions

diff --git a/drivers/usb/host/xhci-mem.c b/drivers/usb/host/xhci-mem.c
index 2cd6111c9707..f1b4f06d4b8b 100644
--- a/drivers/usb/host/xhci-mem.c
+++ b/drivers/usb/host/xhci-mem.c
@@ -2421,6 +2421,8 @@ int xhci_mem_init(struct xhci_hcd *xhci, gfp_t flags)
 	struct device	*dev = xhci_to_hcd(xhci)->self.sysdev;
 	dma_addr_t	dma;
 
+	xhci_dbg_trace(xhci, trace_xhci_dbg_init, "Starting %s", __func__);
+
 	/*
 	 * xHCI section 5.4.6 - Device Context array must be
 	 * "physically contiguous and 64-byte (cache line) aligned".
@@ -2510,6 +2512,7 @@ int xhci_mem_init(struct xhci_hcd *xhci, gfp_t flags)
 	if (xhci_setup_port_arrays(xhci, flags))
 		goto fail;
 
+	xhci_dbg_trace(xhci, trace_xhci_dbg_init, "Finished %s", __func__);
 	return 0;
 
 fail:
diff --git a/drivers/usb/host/xhci.c b/drivers/usb/host/xhci.c
index 674bd40e4e2d..9e2e2c2ed0e0 100644
--- a/drivers/usb/host/xhci.c
+++ b/drivers/usb/host/xhci.c
@@ -536,24 +536,13 @@ static void xhci_set_dev_notifications(struct xhci_hcd *xhci)
 	writel(dev_notf, &xhci->op_regs->dev_notification);
 }
 
-/*
- * Initialize memory for HCD and xHC (one-time init).
- *
- * Program the PAGESIZE register, initialize the device context array, create
- * device contexts (?), set up a command ring segment (or two?), create event
- * ring (one for now).
- */
-static int xhci_init(struct usb_hcd *hcd)
+/* Setup basic xHCI registers */
+static void xhci_init(struct usb_hcd *hcd)
 {
 	struct xhci_hcd *xhci = hcd_to_xhci(hcd);
-	int retval;
 
 	xhci_dbg_trace(xhci, trace_xhci_dbg_init, "Starting %s", __func__);
 
-	retval = xhci_mem_init(xhci, GFP_KERNEL);
-	if (retval)
-		return retval;
-
 	/* Set the Number of Device Slots Enabled to the maximum supported value */
 	xhci_enable_max_dev_slots(xhci);
 
@@ -589,7 +578,6 @@ static int xhci_init(struct usb_hcd *hcd)
 	}
 
 	xhci_dbg_trace(xhci, trace_xhci_dbg_init, "Finished %s", __func__);
-	return 0;
 }
 
 /*-------------------------------------------------------------------------*/
@@ -1190,11 +1178,12 @@ int xhci_resume(struct xhci_hcd *xhci, bool power_lost, bool is_auto_resume)
 		 * first with the primary HCD, and then with the secondary HCD.
 		 * If we don't do the same, the host will never be started.
 		 */
-		xhci_dbg(xhci, "Initialize the xhci_hcd\n");
-		retval = xhci_init(hcd);
+		retval = xhci_mem_init(xhci, GFP_KERNEL);
 		if (retval)
 			return retval;
 
+		xhci_init(hcd);
+
 		xhci_dbg(xhci, "Start the primary HCD\n");
 		retval = xhci_run(hcd);
 		if (!retval && xhci->shared_hcd) {
@@ -5533,12 +5522,13 @@ int xhci_gen_setup(struct usb_hcd *hcd, xhci_get_quirks_t get_quirks)
 
 	memset(xhci->devs, 0, MAX_HC_SLOTS * sizeof(*xhci->devs));
 
-	xhci_dbg(xhci, "Calling HCD init\n");
-	/* Initialize HCD and host controller data structures. */
-	retval = xhci_init(hcd);
+	/* Allocate xHCI data structures */
+	retval = xhci_mem_init(xhci, GFP_KERNEL);
 	if (retval)
 		return retval;
-	xhci_dbg(xhci, "Called HCD init\n");
+
+	/* Initialize HCD and host controller data structures */
+	xhci_init(hcd);
 
 	if (xhci_hcd_is_usb3(hcd))
 		xhci_hcd_init_usb3_data(xhci, hcd);