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	<1420619000-24211-5-git-send-email-vikram.pal@samsung.com>
Date: Wed, 7 Jan 2015 11:26:32 -0200
Message-ID: <CABBYNZKsXryC=yWjq_GvQfLmGKc_FZVYiXgfv86qKTuNTowTug@mail.gmail.com>
Subject: Re: [PATCH 4/6] monitor: Add support for parsing L2CAP extended
 control field
From: Luiz Augusto von Dentz <luiz.dentz@gmail.com>
To: Vikrampal Yadav <vikram.pal@samsung.com>
Cc: "linux-bluetooth@vger.kernel.org" <linux-bluetooth@vger.kernel.org>,
	cpgs@samsung.com
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Sender: linux-bluetooth-owner@vger.kernel.org
List-ID: <linux-bluetooth.vger.kernel.org>

Hi Vikram,

On Wed, Jan 7, 2015 at 6:23 AM, Vikrampal Yadav <vikram.pal@samsung.com> wrote:
> Support for parsing L2CAP extended control field added.
> ---
>  monitor/l2cap.c | 111 ++++++++++++++++++++++++++++++++++++++++++++++++++++++++
>  1 file changed, 111 insertions(+)
>
> diff --git a/monitor/l2cap.c b/monitor/l2cap.c
> index 5f135b0..17104e2 100644
> --- a/monitor/l2cap.c
> +++ b/monitor/l2cap.c
> @@ -44,6 +44,48 @@
>  #include "avctp.h"
>  #include "rfcomm.h"
>
> +/* L2CAP Control Field bit masks */
> +#define L2CAP_CTRL_SAR_MASK            0xC000
> +#define L2CAP_CTRL_REQSEQ_MASK         0x3F00
> +#define L2CAP_CTRL_TXSEQ_MASK          0x007E
> +#define L2CAP_CTRL_SUPERVISE_MASK      0x000C
> +
> +#define L2CAP_CTRL_RETRANS             0x0080
> +#define L2CAP_CTRL_FINAL               0x0080
> +#define L2CAP_CTRL_POLL                        0x0010
> +#define L2CAP_CTRL_FRAME_TYPE          0x0001 /* I- or S-Frame */
> +
> +#define L2CAP_CTRL_TXSEQ_SHIFT         1
> +#define L2CAP_CTRL_SUPER_SHIFT         2
> +#define L2CAP_CTRL_REQSEQ_SHIFT                8
> +#define L2CAP_CTRL_SAR_SHIFT           14
> +
> +#define L2CAP_EXT_CTRL_TXSEQ_MASK      0xFFFC0000
> +#define L2CAP_EXT_CTRL_SAR_MASK                0x00030000
> +#define L2CAP_EXT_CTRL_SUPERVISE_MASK  0x00030000
> +#define L2CAP_EXT_CTRL_REQSEQ_MASK     0x0000FFFC
> +
> +#define L2CAP_EXT_CTRL_POLL            0x00040000
> +#define L2CAP_EXT_CTRL_FINAL           0x00000002
> +#define L2CAP_EXT_CTRL_FRAME_TYPE      0x00000001 /* I- or S-Frame */
> +
> +#define L2CAP_EXT_CTRL_REQSEQ_SHIFT    2
> +#define L2CAP_EXT_CTRL_SAR_SHIFT       16
> +#define L2CAP_EXT_CTRL_SUPER_SHIFT     16
> +#define L2CAP_EXT_CTRL_TXSEQ_SHIFT     18
> +
> +/* L2CAP Supervisory Function */
> +#define L2CAP_SUPER_RR         0x00
> +#define L2CAP_SUPER_REJ                0x01
> +#define L2CAP_SUPER_RNR                0x02
> +#define L2CAP_SUPER_SREJ       0x03
> +
> +/* L2CAP Segmentation and Reassembly */
> +#define L2CAP_SAR_UNSEGMENTED  0x00
> +#define L2CAP_SAR_START                0x01
> +#define L2CAP_SAR_END          0x02
> +#define L2CAP_SAR_CONTINUE     0x03
> +
>  #define MAX_CHAN 64
>
>  struct chan_data {
> @@ -307,6 +349,73 @@ static uint8_t get_ext_ctrl(const struct l2cap_frame *frame)
>         return 0;
>  }
>
> +static char *sar2str(uint8_t sar)
> +{
> +       switch (sar) {
> +       case L2CAP_SAR_UNSEGMENTED:
> +               return "Unsegmented";
> +       case L2CAP_SAR_START:
> +               return "Start";
> +       case L2CAP_SAR_END:
> +               return "End";
> +       case L2CAP_SAR_CONTINUE:
> +               return "Continuation";
> +       default:
> +               return "Bad SAR";
> +       }
> +}
> +
> +static char *supervisory2str(uint8_t supervisory)
> +{
> +       switch (supervisory) {
> +       case L2CAP_SUPER_RR:
> +               return "Receiver Ready (RR)";
> +       case L2CAP_SUPER_REJ:
> +               return "Reject (REJ)";
> +       case L2CAP_SUPER_RNR:
> +               return "Receiver Not Ready (RNR)";
> +       case L2CAP_SUPER_SREJ:
> +               return "Select Reject (SREJ)";
> +       default:
> +               return "Bad Supervisory";
> +       }
> +}
> +
> +static void l2cap_ctrl_ext_parse(struct l2cap_frame *frame, uint32_t ctrl)
> +{
> +       printf("      %s:",
> +               ctrl & L2CAP_EXT_CTRL_FRAME_TYPE ? "S-frame" : "I-frame");
> +
> +       if (ctrl & L2CAP_EXT_CTRL_FRAME_TYPE) {
> +               printf(" %s",
> +               supervisory2str((ctrl & L2CAP_EXT_CTRL_SUPERVISE_MASK) >>
> +                                               L2CAP_EXT_CTRL_SUPER_SHIFT));
> +
> +               if (ctrl & L2CAP_EXT_CTRL_POLL)
> +                       printf(" P-bit");
> +       } else {
> +               uint8_t sar = (ctrl & L2CAP_EXT_CTRL_SAR_MASK) >>
> +                                               L2CAP_EXT_CTRL_SAR_SHIFT;
> +               printf(" %s", sar2str(sar));
> +               if (sar == L2CAP_SAR_START) {
> +                       uint16_t len;
> +
> +                       if (!l2cap_frame_get_le16(frame, &len))
> +                               return;
> +
> +                       printf(" (len %d)", len);
> +               }
> +               printf(" TxSeq %d", (ctrl & L2CAP_EXT_CTRL_TXSEQ_MASK) >>
> +                                               L2CAP_EXT_CTRL_TXSEQ_SHIFT);
> +       }
> +
> +       printf(" ReqSeq %d", (ctrl & L2CAP_EXT_CTRL_REQSEQ_MASK) >>
> +                                               L2CAP_EXT_CTRL_REQSEQ_SHIFT);
> +
> +       if (ctrl & L2CAP_EXT_CTRL_FINAL)
> +               printf(" F-bit");
> +}
> +
>  #define MAX_INDEX 16
>
>  struct index_data {
> @@ -2786,6 +2895,8 @@ static void l2cap_frame(uint16_t index, bool in, uint16_t handle,
>                                                 " [PSM %d mode %d] {chan %d}",
>                                                 cid, size, ctrl32, frame.psm,
>                                                 frame.mode, frame.chan);
> +
> +                               l2cap_ctrl_ext_parse(&frame, ctrl32);
>                         } else {
>                                 if (!l2cap_frame_get_le16(&frame, &ctrl16))
>                                         return;
> --
> 1.9.1


WARNING:SPACE_BEFORE_TAB: please, no space before tabs
#46: FILE: monitor/l2cap.c:84:
+#define L2CAP_SAR_UNSEGMENTED ^I0x00$


-- 
Luiz Augusto von Dentz