Commit c5ec5140 authored by Harvey Harrison's avatar Harvey Harrison Committed by David S. Miller
Browse files

bluetooth: hci_bcsp.c small cleanups/api users 



Use bitrev16 from lib/bitrev.c.

Use the get_unaligned_be16 to get the crc from the packet, create a
small helper function for this.

Fix a shadowed variable sparse warning:
drivers/bluetooth/hci_bcsp.c:218:26: warning: symbol 'hdr' shadows an earlier one
drivers/bluetooth/hci_bcsp.c:187:5: originally declared here

[akpm@linux-foundation.org: select CONFIG_BITREVERSE, noted by akinobu.mita@gmail.com]
Signed-off-by: default avatarHarvey Harrison <harvey.harrison@gmail.com>
Acked-by: default avatarMarcel Holtmann <marcel@holtmann.org>
Signed-off-by: default avatarAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: default avatarDavid S. Miller <davem@davemloft.net>
parent 9a727a25

drivers/bluetooth/Kconfig

+1 −0
Original line number Diff line number Diff line
@@ -71,6 +71,7 @@ config BT_HCIUART_H4 
config BT_HCIUART_BCSP

	bool "BCSP protocol support"

	depends on BT_HCIUART

	select CONFIG_BITREVERSE

	help

	  BCSP (BlueCore Serial Protocol) is serial protocol for communication 

	  between Bluetooth device and host. This protocol is required for non

drivers/bluetooth/hci_bcsp.c

+13 −31
Original line number Diff line number Diff line
@@ -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;

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