xhci: dbc: don't use generic xhci ring allocation functions for dbc.

The generic xhci ring allocations code needs struct xhci_hcd pointer, and
it allocates memory for the rings from dma pools created for the xhci
device.

In order to decouple xhci and DbC we have to create our own ring allocation
and free routines for DbC

Signed-off-by: Mathias Nyman <mathias.nyman@linux.intel.com>
Link: https://lore.kernel.org/r/20200723144530.9992-20-mathias.nyman@linux.intel.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

1 files changed, 70 insertions, 10 deletions

diff --git a/drivers/usb/host/xhci-dbgcap.c b/drivers/usb/host/xhci-dbgcap.c
index fb56198d3aff..b00cbff5e2ca 100644
--- a/drivers/usb/host/xhci-dbgcap.c
+++ b/drivers/usb/host/xhci-dbgcap.c
@@ -22,6 +22,21 @@ static void dbc_free_ctx(struct device *dev, struct xhci_container_ctx *ctx)
 	kfree(ctx);
 }
 
+/* we use only one segment for DbC rings */
+static void dbc_ring_free(struct device *dev, struct xhci_ring *ring)
+{
+	if (!ring)
+		return;
+
+	if (ring->first_seg && ring->first_seg->trbs) {
+		dma_free_coherent(dev, TRB_SEGMENT_SIZE,
+				  ring->first_seg->trbs,
+				  ring->first_seg->dma);
+		kfree(ring->first_seg);
+	}
+	kfree(ring);
+}
+
 static u32 xhci_dbc_populate_strings(struct dbc_str_descs *strings)
 {
 	struct usb_string_descriptor	*s_desc;
@@ -391,6 +406,51 @@ dbc_alloc_ctx(struct device *dev, gfp_t flags)
 	return ctx;
 }
 
+struct xhci_ring *
+xhci_dbc_ring_alloc(struct device *dev, enum xhci_ring_type type, gfp_t flags)
+{
+	struct xhci_ring *ring;
+	struct xhci_segment *seg;
+	dma_addr_t dma;
+
+	ring = kzalloc(sizeof(*ring), flags);
+	if (!ring)
+		return NULL;
+
+	ring->num_segs = 1;
+	ring->type = type;
+
+	seg = kzalloc(sizeof(*seg), flags);
+	if (!seg)
+		goto seg_fail;
+
+	ring->first_seg = seg;
+	ring->last_seg = seg;
+	seg->next = seg;
+
+	seg->trbs = dma_alloc_coherent(dev, TRB_SEGMENT_SIZE, &dma, flags);
+	if (!seg->trbs)
+		goto dma_fail;
+
+	seg->dma = dma;
+
+	/* Only event ring does not use link TRB */
+	if (type != TYPE_EVENT) {
+		union xhci_trb *trb = &seg->trbs[TRBS_PER_SEGMENT - 1];
+
+		trb->link.segment_ptr = cpu_to_le64(dma);
+		trb->link.control = cpu_to_le32(LINK_TOGGLE | TRB_TYPE(TRB_LINK));
+	}
+	INIT_LIST_HEAD(&ring->td_list);
+	xhci_initialize_ring_info(ring, 1);
+	return ring;
+dma_fail:
+	kfree(seg);
+seg_fail:
+	kfree(ring);
+	return NULL;
+}
+
 static int xhci_dbc_mem_init(struct xhci_hcd *xhci, gfp_t flags)
 {
 	int			ret;
@@ -400,15 +460,15 @@ static int xhci_dbc_mem_init(struct xhci_hcd *xhci, gfp_t flags)
 	struct device		*dev = xhci_to_hcd(xhci)->self.controller;
 
 	/* Allocate various rings for events and transfers: */
-	dbc->ring_evt = xhci_ring_alloc(xhci, 1, 1, TYPE_EVENT, 0, flags);
+	dbc->ring_evt = xhci_dbc_ring_alloc(dev, TYPE_EVENT, flags);
 	if (!dbc->ring_evt)
 		goto evt_fail;
 
-	dbc->ring_in = xhci_ring_alloc(xhci, 1, 1, TYPE_BULK, 0, flags);
+	dbc->ring_in = xhci_dbc_ring_alloc(dev, TYPE_BULK, flags);
 	if (!dbc->ring_in)
 		goto in_fail;
 
-	dbc->ring_out = xhci_ring_alloc(xhci, 1, 1, TYPE_BULK, 0, flags);
+	dbc->ring_out = xhci_dbc_ring_alloc(dev, TYPE_BULK, flags);
 	if (!dbc->ring_out)
 		goto out_fail;
 
@@ -452,13 +512,13 @@ string_fail:
 ctx_fail:
 	dbc_erst_free(dev, &dbc->erst);
 erst_fail:
-	xhci_ring_free(xhci, dbc->ring_out);
+	dbc_ring_free(dev, dbc->ring_out);
 	dbc->ring_out = NULL;
 out_fail:
-	xhci_ring_free(xhci, dbc->ring_in);
+	dbc_ring_free(dev, dbc->ring_in);
 	dbc->ring_in = NULL;
 in_fail:
-	xhci_ring_free(xhci, dbc->ring_evt);
+	dbc_ring_free(dev, dbc->ring_evt);
 	dbc->ring_evt = NULL;
 evt_fail:
 	return -ENOMEM;
@@ -483,10 +543,10 @@ static void xhci_dbc_mem_cleanup(struct xhci_hcd *xhci)
 	dbc_free_ctx(dbc->dev, dbc->ctx);
 	dbc->ctx = NULL;
 
-	dbc_erst_free(dev, &dbc->erst);
-	xhci_ring_free(xhci, dbc->ring_out);
-	xhci_ring_free(xhci, dbc->ring_in);
-	xhci_ring_free(xhci, dbc->ring_evt);
+	dbc_erst_free(dbc->dev, &dbc->erst);
+	dbc_ring_free(dbc->dev, dbc->ring_out);
+	dbc_ring_free(dbc->dev, dbc->ring_in);
+	dbc_ring_free(dbc->dev, dbc->ring_evt);
 	dbc->ring_in = NULL;
 	dbc->ring_out = NULL;
 	dbc->ring_evt = NULL;