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-rw-r--r--drivers/bluetooth/h4_recv.h146
1 files changed, 146 insertions, 0 deletions
diff --git a/drivers/bluetooth/h4_recv.h b/drivers/bluetooth/h4_recv.h
new file mode 100644
index 0000000000..4f2c897422
--- /dev/null
+++ b/drivers/bluetooth/h4_recv.h
@@ -0,0 +1,146 @@
+/* SPDX-License-Identifier: GPL-2.0-or-later */
+/*
+ *
+ * Generic Bluetooth HCI UART driver
+ *
+ * Copyright (C) 2015-2018 Intel Corporation
+ */
+
+#include <asm/unaligned.h>
+
+struct h4_recv_pkt {
+ u8 type; /* Packet type */
+ u8 hlen; /* Header length */
+ u8 loff; /* Data length offset in header */
+ u8 lsize; /* Data length field size */
+ u16 maxlen; /* Max overall packet length */
+ int (*recv)(struct hci_dev *hdev, struct sk_buff *skb);
+};
+
+#define H4_RECV_ACL \
+ .type = HCI_ACLDATA_PKT, \
+ .hlen = HCI_ACL_HDR_SIZE, \
+ .loff = 2, \
+ .lsize = 2, \
+ .maxlen = HCI_MAX_FRAME_SIZE \
+
+#define H4_RECV_SCO \
+ .type = HCI_SCODATA_PKT, \
+ .hlen = HCI_SCO_HDR_SIZE, \
+ .loff = 2, \
+ .lsize = 1, \
+ .maxlen = HCI_MAX_SCO_SIZE
+
+#define H4_RECV_EVENT \
+ .type = HCI_EVENT_PKT, \
+ .hlen = HCI_EVENT_HDR_SIZE, \
+ .loff = 1, \
+ .lsize = 1, \
+ .maxlen = HCI_MAX_EVENT_SIZE
+
+static inline struct sk_buff *h4_recv_buf(struct hci_dev *hdev,
+ struct sk_buff *skb,
+ const unsigned char *buffer,
+ int count,
+ const struct h4_recv_pkt *pkts,
+ int pkts_count)
+{
+ /* Check for error from previous call */
+ if (IS_ERR(skb))
+ skb = NULL;
+
+ while (count) {
+ int i, len;
+
+ if (!skb) {
+ for (i = 0; i < pkts_count; i++) {
+ if (buffer[0] != (&pkts[i])->type)
+ continue;
+
+ skb = bt_skb_alloc((&pkts[i])->maxlen,
+ GFP_ATOMIC);
+ if (!skb)
+ return ERR_PTR(-ENOMEM);
+
+ hci_skb_pkt_type(skb) = (&pkts[i])->type;
+ hci_skb_expect(skb) = (&pkts[i])->hlen;
+ break;
+ }
+
+ /* Check for invalid packet type */
+ if (!skb)
+ return ERR_PTR(-EILSEQ);
+
+ count -= 1;
+ buffer += 1;
+ }
+
+ len = min_t(uint, hci_skb_expect(skb) - skb->len, count);
+ skb_put_data(skb, buffer, len);
+
+ count -= len;
+ buffer += len;
+
+ /* Check for partial packet */
+ if (skb->len < hci_skb_expect(skb))
+ continue;
+
+ for (i = 0; i < pkts_count; i++) {
+ if (hci_skb_pkt_type(skb) == (&pkts[i])->type)
+ break;
+ }
+
+ if (i >= pkts_count) {
+ kfree_skb(skb);
+ return ERR_PTR(-EILSEQ);
+ }
+
+ if (skb->len == (&pkts[i])->hlen) {
+ u16 dlen;
+
+ switch ((&pkts[i])->lsize) {
+ case 0:
+ /* No variable data length */
+ dlen = 0;
+ break;
+ case 1:
+ /* Single octet variable length */
+ dlen = skb->data[(&pkts[i])->loff];
+ hci_skb_expect(skb) += dlen;
+
+ if (skb_tailroom(skb) < dlen) {
+ kfree_skb(skb);
+ return ERR_PTR(-EMSGSIZE);
+ }
+ break;
+ case 2:
+ /* Double octet variable length */
+ dlen = get_unaligned_le16(skb->data +
+ (&pkts[i])->loff);
+ hci_skb_expect(skb) += dlen;
+
+ if (skb_tailroom(skb) < dlen) {
+ kfree_skb(skb);
+ return ERR_PTR(-EMSGSIZE);
+ }
+ break;
+ default:
+ /* Unsupported variable length */
+ kfree_skb(skb);
+ return ERR_PTR(-EILSEQ);
+ }
+
+ if (!dlen) {
+ /* No more data, complete frame */
+ (&pkts[i])->recv(hdev, skb);
+ skb = NULL;
+ }
+ } else {
+ /* Complete frame */
+ (&pkts[i])->recv(hdev, skb);
+ skb = NULL;
+ }
+ }
+
+ return skb;
+}