[PATCH 3/4] usb: xhci-plat: add xhci_plat_priv_overwrite

[Howard Yen <howardyen@google.com>]

Add an overwrite to platform specific callback for setting up the
xhci_vendor_ops, allow vendor to store the xhci_vendor_ops and
overwrite them when xhci_plat_probe invoked.

This change is depend on Commit in this patch series
("usb: host: add xhci hooks for USB offload"), vendor needs
to invoke xhci_plat_register_vendor_ops() to register the vendor specific
vendor_ops. And the vendor_ops will overwrite the vendor_ops inside
xhci_plat_priv in xhci_vendor_init() during xhci-plat-hcd probe.

Signed-off-by: Howard Yen <howardyen@google.com>
---
 drivers/usb/host/xhci-plat.c | 20 ++++++++++++++++++++
 drivers/usb/host/xhci-plat.h |  7 +++++++
 2 files changed, 27 insertions(+)

diff --git a/drivers/usb/host/xhci-plat.c b/drivers/usb/host/xhci-plat.c
index 5f8e69089654..a8e217494831 100644
--- a/drivers/usb/host/xhci-plat.c
+++ b/drivers/usb/host/xhci-plat.c
@@ -163,9 +163,26 @@ 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 = xhci_vendor_get_ops(xhci);
+	struct xhci_plat_priv *priv = xhci_to_priv(xhci);
+
+	if (xhci_plat_vendor_overwrite.vendor_ops)
+		ops = priv->vendor_ops = xhci_plat_vendor_overwrite.vendor_ops;
 
 	if (ops && ops->vendor_init)
 		return ops->vendor_init(xhci);
@@ -175,9 +192,12 @@ static int xhci_vendor_init(struct xhci_hcd *xhci)
 static void xhci_vendor_cleanup(struct xhci_hcd *xhci)
 {
 	struct xhci_vendor_ops *ops = xhci_vendor_get_ops(xhci);
+	struct xhci_plat_priv *priv = xhci_to_priv(xhci);
 
 	if (ops && ops->vendor_cleanup)
 		ops->vendor_cleanup(xhci);
+
+	priv->vendor_ops = NULL;
 }
 
 static int xhci_plat_probe(struct platform_device *pdev)
diff --git a/drivers/usb/host/xhci-plat.h b/drivers/usb/host/xhci-plat.h
index 2b2d090c4c01..d85802725208 100644
--- a/drivers/usb/host/xhci-plat.h
+++ b/drivers/usb/host/xhci-plat.h
@@ -22,4 +22,11 @@ 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 */
-- 
2.30.0.284.gd98b1dd5eaa7-goog