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path: root/drivers/bluetooth/hci_bcsp.c
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Diffstat (limited to 'drivers/bluetooth/hci_bcsp.c')
-rw-r--r--drivers/bluetooth/hci_bcsp.c44
1 files changed, 13 insertions, 31 deletions
diff --git a/drivers/bluetooth/hci_bcsp.c b/drivers/bluetooth/hci_bcsp.c
index 696f7528f022..4d37bb312ee3 100644
--- a/drivers/bluetooth/hci_bcsp.c
+++ b/drivers/bluetooth/hci_bcsp.c
@@ -39,6 +39,8 @@
#include <linux/signal.h>
#include <linux/ioctl.h>
#include <linux/skbuff.h>
+#include <linux/bitrev.h>
+#include <asm/unaligned.h>
#include <net/bluetooth/bluetooth.h>
#include <net/bluetooth/hci_core.h>
@@ -124,27 +126,6 @@ static void bcsp_crc_update(u16 *crc, u8 d)
*crc = reg;
}
-/*
- Get reverse of generated crc
-
- Implementation note
- The crc generator (bcsp_crc_init() and bcsp_crc_update())
- creates a reversed crc, so it needs to be swapped back before
- being passed on.
-*/
-static u16 bcsp_crc_reverse(u16 crc)
-{
- u16 b, rev;
-
- for (b = 0, rev = 0; b < 16; b++) {
- rev = rev << 1;
- rev |= (crc & 1);
- crc = crc >> 1;
- }
-
- return (rev);
-}
-
/* ---- BCSP core ---- */
static void bcsp_slip_msgdelim(struct sk_buff *skb)
@@ -235,10 +216,10 @@ static struct sk_buff *bcsp_prepare_pkt(struct bcsp_struct *bcsp, u8 *data,
}
if (hciextn && chan == 5) {
- struct hci_command_hdr *hdr = (struct hci_command_hdr *) data;
+ __le16 opcode = ((struct hci_command_hdr *)data)->opcode;
/* Vendor specific commands */
- if (hci_opcode_ogf(__le16_to_cpu(hdr->opcode)) == 0x3f) {
+ if (hci_opcode_ogf(__le16_to_cpu(opcode)) == 0x3f) {
u8 desc = *(data + HCI_COMMAND_HDR_SIZE);
if ((desc & 0xf0) == 0xc0) {
data += HCI_COMMAND_HDR_SIZE + 1;
@@ -296,7 +277,7 @@ static struct sk_buff *bcsp_prepare_pkt(struct bcsp_struct *bcsp, u8 *data,
/* Put CRC */
if (bcsp->use_crc) {
- bcsp_txmsg_crc = bcsp_crc_reverse(bcsp_txmsg_crc);
+ bcsp_txmsg_crc = bitrev16(bcsp_txmsg_crc);
bcsp_slip_one_byte(nskb, (u8) ((bcsp_txmsg_crc >> 8) & 0x00ff));
bcsp_slip_one_byte(nskb, (u8) (bcsp_txmsg_crc & 0x00ff));
}
@@ -566,6 +547,11 @@ static void bcsp_complete_rx_pkt(struct hci_uart *hu)
bcsp->rx_skb = NULL;
}
+static u16 bscp_get_crc(struct bcsp_struct *bcsp)
+{
+ return get_unaligned_be16(&bcsp->rx_skb->data[bcsp->rx_skb->len - 2]);
+}
+
/* Recv data */
static int bcsp_recv(struct hci_uart *hu, void *data, int count)
{
@@ -624,14 +610,10 @@ static int bcsp_recv(struct hci_uart *hu, void *data, int count)
continue;
case BCSP_W4_CRC:
- if (bcsp_crc_reverse(bcsp->message_crc) !=
- (bcsp->rx_skb->data[bcsp->rx_skb->len - 2] << 8) +
- bcsp->rx_skb->data[bcsp->rx_skb->len - 1]) {
-
+ if (bitrev16(bcsp->message_crc) != bscp_get_crc(bcsp)) {
BT_ERR ("Checksum failed: computed %04x received %04x",
- bcsp_crc_reverse(bcsp->message_crc),
- (bcsp->rx_skb-> data[bcsp->rx_skb->len - 2] << 8) +
- bcsp->rx_skb->data[bcsp->rx_skb->len - 1]);
+ bitrev16(bcsp->message_crc),
+ bscp_get_crc(bcsp));
kfree_skb(bcsp->rx_skb);
bcsp->rx_state = BCSP_W4_PKT_DELIMITER;