Received-SPF: pass (google.com: domain of linux-kernel-owner@vger.kernel.org designates 2620:137:e000::1:18 as permitted sender) client-ip=2620:137:e000::1:18;
From:   Daehwan Jung <dh10.jung@samsung.com>
To:     Mathias Nyman <mathias.nyman@intel.com>,
        Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Cc:     linux-usb@vger.kernel.org (open list:USB XHCI DRIVER),
        linux-kernel@vger.kernel.org (open list),
        Howard Yen <howardyen@google.com>,
        Jack Pham <jackp@codeaurora.org>,
        Puma Hsu <pumahsu@google.com>,
        "J . Avila" <elavila@google.com>,
        Daehwan Jung <dh10.jung@samsung.com>, sc.suh@samsung.com
Subject: [PATCH v3 2/4] usb: host: add xhci hooks for USB offload
Date:   Mon, 21 Mar 2022 17:59:52 +0900
Message-Id: <1647853194-62147-3-git-send-email-dh10.jung@samsung.com>
In-Reply-To: <1647853194-62147-1-git-send-email-dh10.jung@samsung.com>
Content-Type: text/plain; charset="utf-8"
CMS-TYPE: 102P
DLP-Filter: Pass
References: <1647853194-62147-1-git-send-email-dh10.jung@samsung.com>
        <CGME20220321090204epcas2p3b2be5c6b131240e408d12d40c517395c@epcas2p3.samsung.com>
Precedence: bulk

To enable supporting for USB offload, define "offload" in usb controller
node of device tree. "offload" value can be used to determine which type
of offload was been enabled in the SoC.

For example:

&usbdrd_dwc3 {
	...
	/* support usb offloading, 0: disabled, 1: audio */
	offload = <1>;
	...
};

There are several vendor_ops introduced by this patch:

struct xhci_vendor_ops - function callbacks for vendor specific operations
{
	@vendor_init:
		- called for vendor init process during xhci-plat-hcd
		  probe.
	@vendor_cleanup:
		- called for vendor cleanup process during xhci-plat-hcd
		  remove.
	@is_usb_offload_enabled:
		- called to check if usb offload enabled.
	@alloc_dcbaa:
		- called when allocating vendor specific dcbaa during
		  memory initializtion.
	@free_dcbaa:
		- called to free vendor specific dcbaa when cleanup the
		  memory.
	@alloc_transfer_ring:
		- called when vendor specific transfer ring allocation is required
	@free_transfer_ring:
		- called to free vendor specific transfer ring
	@sync_dev_ctx:
		- called when synchronization for device context is required
}

The xhci hooks with prefix "xhci_vendor_" on the ops in xhci_vendor_ops.
For example, vendor_init ops will be invoked by xhci_vendor_init() hook,
is_usb_offload_enabled ops will be invoked by
xhci_vendor_is_usb_offload_enabled(), and so on.

Signed-off-by: Daehwan Jung <dh10.jung@samsung.com>
Signed-off-by: J. Avila <elavila@google.com>
Signed-off-by: Puma Hsu <pumahsu@google.com>
Signed-off-by: Howard Yen <howardyen@google.com>
---
 drivers/usb/host/xhci-hub.c  |   5 ++
 drivers/usb/host/xhci-mem.c  | 131 +++++++++++++++++++++++++++++++----
 drivers/usb/host/xhci-plat.c |  43 +++++++++++-
 drivers/usb/host/xhci-plat.h |   7 ++
 drivers/usb/host/xhci.c      |  80 ++++++++++++++++++++-
 drivers/usb/host/xhci.h      |  46 ++++++++++++
 6 files changed, 295 insertions(+), 17 deletions(-)

diff --git a/drivers/usb/host/xhci-hub.c b/drivers/usb/host/xhci-hub.c
index 56546aaa93c7..aea72ffce820 100644
--- a/drivers/usb/host/xhci-hub.c
+++ b/drivers/usb/host/xhci-hub.c
@@ -535,8 +535,13 @@ static int xhci_stop_device(struct xhci_hcd *xhci, int slot_id, int suspend)
 	    cmd->status == COMP_COMMAND_RING_STOPPED) {
 		xhci_warn(xhci, "Timeout while waiting for stop endpoint command\n");
 		ret = -ETIME;
+		goto cmd_cleanup;
 	}
 
+	ret = xhci_vendor_sync_dev_ctx(xhci, slot_id);
+	if (ret)
+		xhci_warn(xhci, "Sync device context failed, ret=%d\n", ret);
+
 cmd_cleanup:
 	xhci_free_command(xhci, cmd);
 	return ret;
diff --git a/drivers/usb/host/xhci-mem.c b/drivers/usb/host/xhci-mem.c
index 82b9f90c0f27..5ee0ffb676d3 100644
--- a/drivers/usb/host/xhci-mem.c
+++ b/drivers/usb/host/xhci-mem.c
@@ -365,6 +365,54 @@ static int xhci_alloc_segments_for_ring(struct xhci_hcd *xhci,
 	return 0;
 }
 
+static void xhci_vendor_free_container_ctx(struct xhci_hcd *xhci, struct xhci_container_ctx *ctx)
+{
+	struct xhci_vendor_ops *ops = xhci_vendor_get_ops(xhci);
+
+	if (ops && ops->free_container_ctx)
+		ops->free_container_ctx(xhci, ctx);
+}
+
+static void xhci_vendor_alloc_container_ctx(struct xhci_hcd *xhci, struct xhci_container_ctx *ctx,
+					    int type, gfp_t flags)
+{
+	struct xhci_vendor_ops *ops = xhci_vendor_get_ops(xhci);
+
+	if (ops && ops->alloc_container_ctx)
+		ops->alloc_container_ctx(xhci, ctx, type, flags);
+}
+
+static struct xhci_ring *xhci_vendor_alloc_transfer_ring(struct xhci_hcd *xhci,
+		u32 endpoint_type, enum xhci_ring_type ring_type,
+		unsigned int max_packet, gfp_t mem_flags)
+{
+	struct xhci_vendor_ops *ops = xhci_vendor_get_ops(xhci);
+
+	if (ops && ops->alloc_transfer_ring)
+		return ops->alloc_transfer_ring(xhci, endpoint_type, ring_type,
+				max_packet, mem_flags);
+	return 0;
+}
+
+void xhci_vendor_free_transfer_ring(struct xhci_hcd *xhci,
+		struct xhci_ring *ring, unsigned int ep_index)
+{
+	struct xhci_vendor_ops *ops = xhci_vendor_get_ops(xhci);
+
+	if (ops && ops->free_transfer_ring)
+		ops->free_transfer_ring(xhci, ring, ep_index);
+}
+
+bool xhci_vendor_is_usb_offload_enabled(struct xhci_hcd *xhci,
+		struct xhci_virt_device *virt_dev, unsigned int ep_index)
+{
+	struct xhci_vendor_ops *ops = xhci_vendor_get_ops(xhci);
+
+	if (ops && ops->is_usb_offload_enabled)
+		return ops->is_usb_offload_enabled(xhci, virt_dev, ep_index);
+	return false;
+}
+
 /*
  * Create a new ring with zero or more segments.
  *
@@ -417,7 +465,11 @@ void xhci_free_endpoint_ring(struct xhci_hcd *xhci,
 		struct xhci_virt_device *virt_dev,
 		unsigned int ep_index)
 {
-	xhci_ring_free(xhci, virt_dev->eps[ep_index].ring);
+	if (xhci_vendor_is_usb_offload_enabled(xhci, virt_dev, ep_index))
+		xhci_vendor_free_transfer_ring(xhci, virt_dev->eps[ep_index].ring, ep_index);
+	else
+		xhci_ring_free(xhci, virt_dev->eps[ep_index].ring);
+
 	virt_dev->eps[ep_index].ring = NULL;
 }
 
@@ -475,6 +527,7 @@ struct xhci_container_ctx *xhci_alloc_container_ctx(struct xhci_hcd *xhci,
 {
 	struct xhci_container_ctx *ctx;
 	struct device *dev = xhci_to_hcd(xhci)->self.sysdev;
+	struct xhci_vendor_ops *ops = xhci_vendor_get_ops(xhci);
 
 	if ((type != XHCI_CTX_TYPE_DEVICE) && (type != XHCI_CTX_TYPE_INPUT))
 		return NULL;
@@ -488,7 +541,12 @@ struct xhci_container_ctx *xhci_alloc_container_ctx(struct xhci_hcd *xhci,
 	if (type == XHCI_CTX_TYPE_INPUT)
 		ctx->size += CTX_SIZE(xhci->hcc_params);
 
-	ctx->bytes = dma_pool_zalloc(xhci->device_pool, flags, &ctx->dma);
+	if (xhci_vendor_is_usb_offload_enabled(xhci, NULL, 0) &&
+	    (ops && ops->alloc_container_ctx))
+		xhci_vendor_alloc_container_ctx(xhci, ctx, type, flags);
+	else
+		ctx->bytes = dma_pool_zalloc(xhci->device_pool, flags, &ctx->dma);
+
 	if (!ctx->bytes) {
 		kfree(ctx);
 		return NULL;
@@ -499,9 +557,16 @@ struct xhci_container_ctx *xhci_alloc_container_ctx(struct xhci_hcd *xhci,
 void xhci_free_container_ctx(struct xhci_hcd *xhci,
 			     struct xhci_container_ctx *ctx)
 {
+	struct xhci_vendor_ops *ops = xhci_vendor_get_ops(xhci);
+
 	if (!ctx)
 		return;
-	dma_pool_free(xhci->device_pool, ctx->bytes, ctx->dma);
+	if (xhci_vendor_is_usb_offload_enabled(xhci, NULL, 0) &&
+	    (ops && ops->free_container_ctx))
+		xhci_vendor_free_container_ctx(xhci, ctx);
+	else
+		dma_pool_free(xhci->device_pool, ctx->bytes, ctx->dma);
+
 	kfree(ctx);
 }
 
@@ -894,7 +959,7 @@ void xhci_free_virt_device(struct xhci_hcd *xhci, int slot_id)
 
 	for (i = 0; i < 31; i++) {
 		if (dev->eps[i].ring)
-			xhci_ring_free(xhci, dev->eps[i].ring);
+			xhci_free_endpoint_ring(xhci, dev, i);
 		if (dev->eps[i].stream_info)
 			xhci_free_stream_info(xhci,
 					dev->eps[i].stream_info);
@@ -1492,8 +1557,16 @@ int xhci_endpoint_init(struct xhci_hcd *xhci,
 		mult = 0;
 
 	/* Set up the endpoint ring */
-	virt_dev->eps[ep_index].new_ring =
-		xhci_ring_alloc(xhci, 2, 1, ring_type, max_packet, mem_flags);
+	if (xhci_vendor_is_usb_offload_enabled(xhci, virt_dev, ep_index) &&
+	    usb_endpoint_xfer_isoc(&ep->desc)) {
+		virt_dev->eps[ep_index].new_ring =
+			xhci_vendor_alloc_transfer_ring(xhci, endpoint_type, ring_type,
+							max_packet, mem_flags);
+	} else {
+		virt_dev->eps[ep_index].new_ring =
+			xhci_ring_alloc(xhci, 2, 1, ring_type, max_packet, mem_flags);
+	}
+
 	if (!virt_dev->eps[ep_index].new_ring)
 		return -ENOMEM;
 
@@ -1837,6 +1910,24 @@ void xhci_free_erst(struct xhci_hcd *xhci, struct xhci_erst *erst)
 	erst->entries = NULL;
 }
 
+static struct xhci_device_context_array *xhci_vendor_alloc_dcbaa(
+		struct xhci_hcd *xhci, gfp_t flags)
+{
+	struct xhci_vendor_ops *ops = xhci_vendor_get_ops(xhci);
+
+	if (ops && ops->alloc_dcbaa)
+		return ops->alloc_dcbaa(xhci, flags);
+	return 0;
+}
+
+static void xhci_vendor_free_dcbaa(struct xhci_hcd *xhci)
+{
+	struct xhci_vendor_ops *ops = xhci_vendor_get_ops(xhci);
+
+	if (ops && ops->free_dcbaa)
+		ops->free_dcbaa(xhci);
+}
+
 void xhci_mem_cleanup(struct xhci_hcd *xhci)
 {
 	struct device	*dev = xhci_to_hcd(xhci)->self.sysdev;
@@ -1888,9 +1979,13 @@ void xhci_mem_cleanup(struct xhci_hcd *xhci)
 	xhci_dbg_trace(xhci, trace_xhci_dbg_init,
 			"Freed medium stream array pool");
 
-	if (xhci->dcbaa)
-		dma_free_coherent(dev, sizeof(*xhci->dcbaa),
-				xhci->dcbaa, xhci->dcbaa->dma);
+	if (xhci_vendor_is_usb_offload_enabled(xhci, NULL, 0)) {
+		xhci_vendor_free_dcbaa(xhci);
+	} else {
+		if (xhci->dcbaa)
+			dma_free_coherent(dev, sizeof(*xhci->dcbaa),
+					xhci->dcbaa, xhci->dcbaa->dma);
+	}
 	xhci->dcbaa = NULL;
 
 	scratchpad_free(xhci);
@@ -2427,15 +2522,21 @@ int xhci_mem_init(struct xhci_hcd *xhci, gfp_t flags)
 	 * xHCI section 5.4.6 - Device Context array must be
 	 * "physically contiguous and 64-byte (cache line) aligned".
 	 */
-	xhci->dcbaa = dma_alloc_coherent(dev, sizeof(*xhci->dcbaa), &dma,
-			flags);
-	if (!xhci->dcbaa)
-		goto fail;
-	xhci->dcbaa->dma = dma;
+	if (xhci_vendor_is_usb_offload_enabled(xhci, NULL, 0)) {
+		xhci->dcbaa = xhci_vendor_alloc_dcbaa(xhci, flags);
+		if (!xhci->dcbaa)
+			goto fail;
+	} else {
+		xhci->dcbaa = dma_alloc_coherent(dev, sizeof(*xhci->dcbaa), &dma,
+				flags);
+		if (!xhci->dcbaa)
+			goto fail;
+		xhci->dcbaa->dma = dma;
+	}
 	xhci_dbg_trace(xhci, trace_xhci_dbg_init,
 			"// Device context base array address = 0x%llx (DMA), %p (virt)",
 			(unsigned long long)xhci->dcbaa->dma, xhci->dcbaa);
-	xhci_write_64(xhci, dma, &xhci->op_regs->dcbaa_ptr);
+	xhci_write_64(xhci, xhci->dcbaa->dma, &xhci->op_regs->dcbaa_ptr);
 
 	/*
 	 * Initialize the ring segment pool.  The ring must be a contiguous
diff --git a/drivers/usb/host/xhci-plat.c b/drivers/usb/host/xhci-plat.c
index 649ffd861b44..3d2fe4d77f38 100644
--- a/drivers/usb/host/xhci-plat.c
+++ b/drivers/usb/host/xhci-plat.c
@@ -173,6 +173,41 @@ static const struct of_device_id usb_xhci_of_match[] = {
 MODULE_DEVICE_TABLE(of, usb_xhci_of_match);
 #endif
 
+static struct xhci_plat_priv_overwrite xhci_plat_vendor_overwrite;
+
+int xhci_plat_register_vendor_ops(struct xhci_vendor_ops *vendor_ops)
+{
+	if (vendor_ops == NULL)
+		return -EINVAL;
+
+	xhci_plat_vendor_overwrite.vendor_ops = vendor_ops;
+
+	return 0;
+}
+EXPORT_SYMBOL_GPL(xhci_plat_register_vendor_ops);
+
+static int xhci_vendor_init(struct xhci_hcd *xhci)
+{
+	struct xhci_vendor_ops *ops = NULL;
+
+	if (xhci_plat_vendor_overwrite.vendor_ops)
+		ops = xhci->vendor_ops = xhci_plat_vendor_overwrite.vendor_ops;
+
+	if (ops && ops->vendor_init)
+		return ops->vendor_init(xhci);
+	return 0;
+}
+
+static void xhci_vendor_cleanup(struct xhci_hcd *xhci)
+{
+	struct xhci_vendor_ops *ops = xhci_vendor_get_ops(xhci);
+
+	if (ops && ops->vendor_cleanup)
+		ops->vendor_cleanup(xhci);
+
+	xhci->vendor_ops = NULL;
+}
+
 static int xhci_plat_probe(struct platform_device *pdev)
 {
 	const struct xhci_plat_priv *priv_match;
@@ -321,6 +356,10 @@ static int xhci_plat_probe(struct platform_device *pdev)
 			goto put_usb3_hcd;
 	}
 
+	ret = xhci_vendor_init(xhci);
+	if (ret)
+		goto disable_usb_phy;
+
 	hcd->tpl_support = of_usb_host_tpl_support(sysdev->of_node);
 	xhci->shared_hcd->tpl_support = hcd->tpl_support;
 	if (priv && (priv->quirks & XHCI_SKIP_PHY_INIT))
@@ -393,8 +432,10 @@ static int xhci_plat_remove(struct platform_device *dev)
 	usb_phy_shutdown(hcd->usb_phy);
 
 	usb_remove_hcd(hcd);
-	usb_put_hcd(shared_hcd);
 
+	xhci_vendor_cleanup(xhci);
+
+	usb_put_hcd(shared_hcd);
 	clk_disable_unprepare(clk);
 	clk_disable_unprepare(reg_clk);
 	usb_put_hcd(hcd);
diff --git a/drivers/usb/host/xhci-plat.h b/drivers/usb/host/xhci-plat.h
index 1fb149d1fbce..18b349883eea 100644
--- a/drivers/usb/host/xhci-plat.h
+++ b/drivers/usb/host/xhci-plat.h
@@ -21,4 +21,11 @@ struct xhci_plat_priv {
 
 #define hcd_to_xhci_priv(h) ((struct xhci_plat_priv *)hcd_to_xhci(h)->priv)
 #define xhci_to_priv(x) ((struct xhci_plat_priv *)(x)->priv)
+
+struct xhci_plat_priv_overwrite {
+	struct xhci_vendor_ops *vendor_ops;
+};
+
+int xhci_plat_register_vendor_ops(struct xhci_vendor_ops *vendor_ops);
+
 #endif	/* _XHCI_PLAT_H */
diff --git a/drivers/usb/host/xhci.c b/drivers/usb/host/xhci.c
index 8f53672dcd97..4e4fcf97ba42 100644
--- a/drivers/usb/host/xhci.c
+++ b/drivers/usb/host/xhci.c
@@ -2975,6 +2975,14 @@ static int xhci_configure_endpoint(struct xhci_hcd *xhci,
 			xhci_finish_resource_reservation(xhci, ctrl_ctx);
 		spin_unlock_irqrestore(&xhci->lock, flags);
 	}
+	if (ret)
+		goto failed;
+
+	ret = xhci_vendor_sync_dev_ctx(xhci, udev->slot_id);
+	if (ret)
+		xhci_warn(xhci, "sync device context failed, ret=%d", ret);
+
+failed:
 	return ret;
 }
 
@@ -3118,7 +3126,11 @@ void xhci_reset_bandwidth(struct usb_hcd *hcd, struct usb_device *udev)
 	for (i = 0; i < 31; i++) {
 		if (virt_dev->eps[i].new_ring) {
 			xhci_debugfs_remove_endpoint(xhci, virt_dev, i);
-			xhci_ring_free(xhci, virt_dev->eps[i].new_ring);
+			if (xhci_vendor_is_usb_offload_enabled(xhci, virt_dev, i))
+				xhci_vendor_free_transfer_ring(xhci, virt_dev->eps[i].new_ring, i);
+			else
+				xhci_ring_free(xhci, virt_dev->eps[i].new_ring);
+
 			virt_dev->eps[i].new_ring = NULL;
 		}
 	}
@@ -3279,6 +3291,13 @@ static void xhci_endpoint_reset(struct usb_hcd *hcd,
 
 	wait_for_completion(stop_cmd->completion);
 
+	err = xhci_vendor_sync_dev_ctx(xhci, udev->slot_id);
+	if (err) {
+		xhci_warn(xhci, "%s: Failed to sync device context failed, err=%d",
+			  __func__, err);
+		goto cleanup;
+	}
+
 	spin_lock_irqsave(&xhci->lock, flags);
 
 	/* config ep command clears toggle if add and drop ep flags are set */
@@ -3310,6 +3329,11 @@ static void xhci_endpoint_reset(struct usb_hcd *hcd,
 
 	wait_for_completion(cfg_cmd->completion);
 
+	err = xhci_vendor_sync_dev_ctx(xhci, udev->slot_id);
+	if (err)
+		xhci_warn(xhci, "%s: Failed to sync device context failed, err=%d",
+			  __func__, err);
+
 	xhci_free_command(xhci, cfg_cmd);
 cleanup:
 	xhci_free_command(xhci, stop_cmd);
@@ -3855,6 +3879,13 @@ static int xhci_discover_or_reset_device(struct usb_hcd *hcd,
 	/* Wait for the Reset Device command to finish */
 	wait_for_completion(reset_device_cmd->completion);
 
+	ret = xhci_vendor_sync_dev_ctx(xhci, slot_id);
+	if (ret) {
+		xhci_warn(xhci, "%s: Failed to sync device context failed, err=%d",
+			  __func__, ret);
+		goto command_cleanup;
+	}
+
 	/* The Reset Device command can't fail, according to the 0.95/0.96 spec,
 	 * unless we tried to reset a slot ID that wasn't enabled,
 	 * or the device wasn't in the addressed or configured state.
@@ -4100,6 +4131,14 @@ int xhci_alloc_dev(struct usb_hcd *hcd, struct usb_device *udev)
 		xhci_warn(xhci, "Could not allocate xHCI USB device data structures\n");
 		goto disable_slot;
 	}
+
+	ret = xhci_vendor_sync_dev_ctx(xhci, slot_id);
+	if (ret) {
+		xhci_warn(xhci, "%s: Failed to sync device context failed, err=%d",
+			  __func__, ret);
+		goto disable_slot;
+	}
+
 	vdev = xhci->devs[slot_id];
 	slot_ctx = xhci_get_slot_ctx(xhci, vdev->out_ctx);
 	trace_xhci_alloc_dev(slot_ctx);
@@ -4230,6 +4269,13 @@ static int xhci_setup_device(struct usb_hcd *hcd, struct usb_device *udev,
 	/* ctrl tx can take up to 5 sec; XXX: need more time for xHC? */
 	wait_for_completion(command->completion);
 
+	ret = xhci_vendor_sync_dev_ctx(xhci, udev->slot_id);
+	if (ret) {
+		xhci_warn(xhci, "%s: Failed to sync device context failed, err=%d",
+			  __func__, ret);
+		goto out;
+	}
+
 	/* FIXME: From section 4.3.4: "Software shall be responsible for timing
 	 * the SetAddress() "recovery interval" required by USB and aborting the
 	 * command on a timeout.
@@ -4382,6 +4428,14 @@ static int __maybe_unused xhci_change_max_exit_latency(struct xhci_hcd *xhci,
 		return -ENOMEM;
 	}
 
+	ret = xhci_vendor_sync_dev_ctx(xhci, udev->slot_id);
+	if (ret) {
+		spin_unlock_irqrestore(&xhci->lock, flags);
+		xhci_warn(xhci, "%s: Failed to sync device context failed, err=%d",
+			  __func__, ret);
+		return ret;
+	}
+
 	xhci_slot_copy(xhci, command->in_ctx, virt_dev->out_ctx);
 	spin_unlock_irqrestore(&xhci->lock, flags);
 
@@ -4409,6 +4463,21 @@ static int __maybe_unused xhci_change_max_exit_latency(struct xhci_hcd *xhci,
 	return ret;
 }
 
+struct xhci_vendor_ops *xhci_vendor_get_ops(struct xhci_hcd *xhci)
+{
+	return xhci->vendor_ops;
+}
+EXPORT_SYMBOL_GPL(xhci_vendor_get_ops);
+
+int xhci_vendor_sync_dev_ctx(struct xhci_hcd *xhci, unsigned int slot_id)
+{
+	struct xhci_vendor_ops *ops = xhci_vendor_get_ops(xhci);
+
+	if (ops && ops->sync_dev_ctx)
+		return ops->sync_dev_ctx(xhci, slot_id);
+	return 0;
+}
+
 #ifdef CONFIG_PM
 
 /* BESL to HIRD Encoding array for USB2 LPM */
@@ -5133,6 +5202,15 @@ static int xhci_update_hub_device(struct usb_hcd *hcd, struct usb_device *hdev,
 		return -ENOMEM;
 	}
 
+	ret = xhci_vendor_sync_dev_ctx(xhci, hdev->slot_id);
+	if (ret) {
+		xhci_warn(xhci, "%s: Failed to sync device context failed, err=%d",
+			  __func__, ret);
+		xhci_free_command(xhci, config_cmd);
+		spin_unlock_irqrestore(&xhci->lock, flags);
+		return ret;
+	}
+
 	xhci_slot_copy(xhci, config_cmd->in_ctx, vdev->out_ctx);
 	ctrl_ctx->add_flags |= cpu_to_le32(SLOT_FLAG);
 	slot_ctx = xhci_get_slot_ctx(xhci, config_cmd->in_ctx);
diff --git a/drivers/usb/host/xhci.h b/drivers/usb/host/xhci.h
index 473a33ce299e..f690a5dc9eb3 100644
--- a/drivers/usb/host/xhci.h
+++ b/drivers/usb/host/xhci.h
@@ -1929,6 +1929,9 @@ struct xhci_hcd {
 	struct list_head	regset_list;
 
 	void			*dbc;
+
+	struct xhci_vendor_ops *vendor_ops;
+
 	/* platform-specific data -- must come last */
 	unsigned long		priv[] __aligned(sizeof(s64));
 };
@@ -2207,6 +2210,49 @@ static inline struct xhci_ring *xhci_urb_to_transfer_ring(struct xhci_hcd *xhci,
 					urb->stream_id);
 }
 
+/**
+ * struct xhci_vendor_ops - function callbacks for vendor specific operations
+ * @vendor_init: called for vendor init process
+ * @vendor_cleanup: called for vendor cleanup process
+ * @is_usb_offload_enabled: called to check if usb offload enabled
+ * @alloc_dcbaa: called when allocating vendor specific dcbaa
+ * @free_dcbaa: called to free vendor specific dcbaa
+ * @alloc_transfer_ring: called when remote transfer ring allocation is required
+ * @free_transfer_ring: called to free vendor specific transfer ring
+ * @sync_dev_ctx: called when synchronization for device context is required
+ * @alloc_container_ctx: called when allocating vendor specific container context
+ * @free_container_ctx: called to free vendor specific container context
+ */
+struct xhci_vendor_ops {
+	int (*vendor_init)(struct xhci_hcd *xhci);
+	void (*vendor_cleanup)(struct xhci_hcd *xhci);
+	bool (*is_usb_offload_enabled)(struct xhci_hcd *xhci,
+				       struct xhci_virt_device *vdev,
+				       unsigned int ep_index);
+
+	struct xhci_device_context_array *(*alloc_dcbaa)(struct xhci_hcd *xhci,
+							 gfp_t flags);
+	void (*free_dcbaa)(struct xhci_hcd *xhci);
+
+	struct xhci_ring *(*alloc_transfer_ring)(struct xhci_hcd *xhci,
+			u32 endpoint_type, enum xhci_ring_type ring_type,
+			unsigned int max_packet, gfp_t mem_flags);
+	void (*free_transfer_ring)(struct xhci_hcd *xhci,
+			struct xhci_ring *ring, unsigned int ep_index);
+	int (*sync_dev_ctx)(struct xhci_hcd *xhci, unsigned int slot_id);
+	void (*alloc_container_ctx)(struct xhci_hcd *xhci, struct xhci_container_ctx *ctx,
+				    int type, gfp_t flags);
+	void (*free_container_ctx)(struct xhci_hcd *xhci, struct xhci_container_ctx *ctx);
+};
+
+struct xhci_vendor_ops *xhci_vendor_get_ops(struct xhci_hcd *xhci);
+
+int xhci_vendor_sync_dev_ctx(struct xhci_hcd *xhci, unsigned int slot_id);
+void xhci_vendor_free_transfer_ring(struct xhci_hcd *xhci,
+		struct xhci_ring *ring, unsigned int ep_index);
+bool xhci_vendor_is_usb_offload_enabled(struct xhci_hcd *xhci,
+		struct xhci_virt_device *virt_dev, unsigned int ep_index);
+
 /*
  * TODO: As per spec Isochronous IDT transmissions are supported. We bypass
  * them anyways as we where unable to find a device that matches the
-- 
2.31.1