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path: root/drivers/bluetooth/hci_h4.c
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Diffstat (limited to 'drivers/bluetooth/hci_h4.c')
-rw-r--r--drivers/bluetooth/hci_h4.c274
1 files changed, 274 insertions, 0 deletions
diff --git a/drivers/bluetooth/hci_h4.c b/drivers/bluetooth/hci_h4.c
new file mode 100644
index 000000000..1d0cdf023
--- /dev/null
+++ b/drivers/bluetooth/hci_h4.c
@@ -0,0 +1,274 @@
+// SPDX-License-Identifier: GPL-2.0-or-later
+/*
+ *
+ * Bluetooth HCI UART driver
+ *
+ * Copyright (C) 2000-2001 Qualcomm Incorporated
+ * Copyright (C) 2002-2003 Maxim Krasnyansky <maxk@qualcomm.com>
+ * Copyright (C) 2004-2005 Marcel Holtmann <marcel@holtmann.org>
+ */
+
+#include <linux/module.h>
+
+#include <linux/kernel.h>
+#include <linux/init.h>
+#include <linux/types.h>
+#include <linux/fcntl.h>
+#include <linux/interrupt.h>
+#include <linux/ptrace.h>
+#include <linux/poll.h>
+
+#include <linux/slab.h>
+#include <linux/tty.h>
+#include <linux/errno.h>
+#include <linux/string.h>
+#include <linux/signal.h>
+#include <linux/ioctl.h>
+#include <linux/skbuff.h>
+#include <asm/unaligned.h>
+
+#include <net/bluetooth/bluetooth.h>
+#include <net/bluetooth/hci_core.h>
+
+#include "hci_uart.h"
+
+struct h4_struct {
+ struct sk_buff *rx_skb;
+ struct sk_buff_head txq;
+};
+
+/* Initialize protocol */
+static int h4_open(struct hci_uart *hu)
+{
+ struct h4_struct *h4;
+
+ BT_DBG("hu %p", hu);
+
+ h4 = kzalloc(sizeof(*h4), GFP_KERNEL);
+ if (!h4)
+ return -ENOMEM;
+
+ skb_queue_head_init(&h4->txq);
+
+ hu->priv = h4;
+ return 0;
+}
+
+/* Flush protocol data */
+static int h4_flush(struct hci_uart *hu)
+{
+ struct h4_struct *h4 = hu->priv;
+
+ BT_DBG("hu %p", hu);
+
+ skb_queue_purge(&h4->txq);
+
+ return 0;
+}
+
+/* Close protocol */
+static int h4_close(struct hci_uart *hu)
+{
+ struct h4_struct *h4 = hu->priv;
+
+ BT_DBG("hu %p", hu);
+
+ skb_queue_purge(&h4->txq);
+
+ kfree_skb(h4->rx_skb);
+
+ hu->priv = NULL;
+ kfree(h4);
+
+ return 0;
+}
+
+/* Enqueue frame for transmission (padding, crc, etc) */
+static int h4_enqueue(struct hci_uart *hu, struct sk_buff *skb)
+{
+ struct h4_struct *h4 = hu->priv;
+
+ BT_DBG("hu %p skb %p", hu, skb);
+
+ /* Prepend skb with frame type */
+ memcpy(skb_push(skb, 1), &hci_skb_pkt_type(skb), 1);
+ skb_queue_tail(&h4->txq, skb);
+
+ return 0;
+}
+
+static const struct h4_recv_pkt h4_recv_pkts[] = {
+ { H4_RECV_ACL, .recv = hci_recv_frame },
+ { H4_RECV_SCO, .recv = hci_recv_frame },
+ { H4_RECV_EVENT, .recv = hci_recv_frame },
+ { H4_RECV_ISO, .recv = hci_recv_frame },
+};
+
+/* Recv data */
+static int h4_recv(struct hci_uart *hu, const void *data, int count)
+{
+ struct h4_struct *h4 = hu->priv;
+
+ if (!test_bit(HCI_UART_REGISTERED, &hu->flags))
+ return -EUNATCH;
+
+ h4->rx_skb = h4_recv_buf(hu->hdev, h4->rx_skb, data, count,
+ h4_recv_pkts, ARRAY_SIZE(h4_recv_pkts));
+ if (IS_ERR(h4->rx_skb)) {
+ int err = PTR_ERR(h4->rx_skb);
+ bt_dev_err(hu->hdev, "Frame reassembly failed (%d)", err);
+ h4->rx_skb = NULL;
+ return err;
+ }
+
+ return count;
+}
+
+static struct sk_buff *h4_dequeue(struct hci_uart *hu)
+{
+ struct h4_struct *h4 = hu->priv;
+ return skb_dequeue(&h4->txq);
+}
+
+static const struct hci_uart_proto h4p = {
+ .id = HCI_UART_H4,
+ .name = "H4",
+ .open = h4_open,
+ .close = h4_close,
+ .recv = h4_recv,
+ .enqueue = h4_enqueue,
+ .dequeue = h4_dequeue,
+ .flush = h4_flush,
+};
+
+int __init h4_init(void)
+{
+ return hci_uart_register_proto(&h4p);
+}
+
+int __exit h4_deinit(void)
+{
+ return hci_uart_unregister_proto(&h4p);
+}
+
+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)
+{
+ struct hci_uart *hu = hci_get_drvdata(hdev);
+ u8 alignment = hu->alignment ? hu->alignment : 1;
+
+ /* Check for error from previous call */
+ if (IS_ERR(skb))
+ skb = NULL;
+
+ while (count) {
+ int i, len;
+
+ /* remove padding bytes from buffer */
+ for (; hu->padding && count > 0; hu->padding--) {
+ count--;
+ buffer++;
+ }
+ if (!count)
+ break;
+
+ 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) {
+ hu->padding = (skb->len + 1) % alignment;
+ hu->padding = (alignment - hu->padding) % alignment;
+
+ /* No more data, complete frame */
+ (&pkts[i])->recv(hdev, skb);
+ skb = NULL;
+ }
+ } else {
+ hu->padding = (skb->len + 1) % alignment;
+ hu->padding = (alignment - hu->padding) % alignment;
+
+ /* Complete frame */
+ (&pkts[i])->recv(hdev, skb);
+ skb = NULL;
+ }
+ }
+
+ return skb;
+}
+EXPORT_SYMBOL_GPL(h4_recv_buf);