Hi Gowtham, On Tue, Dec 2, 2014 at 4:39 PM, Gowtham Anandha Babu <gowtham.ab@xxxxxxxxxxx> wrote: > Hi Luiz, > >> -----Original Message----- >> From: linux-bluetooth-owner@xxxxxxxxxxxxxxx [mailto:linux-bluetooth- >> owner@xxxxxxxxxxxxxxx] On Behalf Of Luiz Augusto von Dentz >> Sent: Tuesday, December 02, 2014 6:11 PM >> To: Gowtham Anandha Babu >> Cc: linux-bluetooth@xxxxxxxxxxxxxxx; Dmitry Kasatkin; Bharat Panda; >> cpgs@xxxxxxxxxxx >> Subject: Re: [PATCH 1/5] monitor/rfcomm.c: Add support for MSC frame >> decoding >> >> Hi Gowtham, >> >> On Tue, Dec 2, 2014 at 2:37 PM, Gowtham Anandha Babu >> <gowtham.ab@xxxxxxxxxxx> wrote: >> > Hi Luiz, >> > >> >> -----Original Message----- >> >> From: Gowtham Anandha Babu [mailto:gowtham.ab@xxxxxxxxxxx] >> >> Sent: Tuesday, December 02, 2014 4:30 PM >> >> To: 'Luiz Augusto von Dentz' >> >> Cc: 'linux-bluetooth@xxxxxxxxxxxxxxx'; 'Dmitry Kasatkin'; 'Bharat >> >> Panda'; 'cpgs@xxxxxxxxxxx' >> >> Subject: RE: [PATCH 1/5] monitor/rfcomm.c: Add support for MSC frame >> >> decoding >> >> >> >> Hi Luiz, >> >> >> >> > -----Original Message----- >> >> > From: linux-bluetooth-owner@xxxxxxxxxxxxxxx >> >> > [mailto:linux-bluetooth- owner@xxxxxxxxxxxxxxx] On Behalf Of Luiz >> >> > Augusto von Dentz >> >> > Sent: Tuesday, December 02, 2014 4:22 PM >> >> > To: Gowtham Anandha Babu >> >> > Cc: linux-bluetooth@xxxxxxxxxxxxxxx; Dmitry Kasatkin; Bharat Panda; >> >> > cpgs@xxxxxxxxxxx >> >> > Subject: Re: [PATCH 1/5] monitor/rfcomm.c: Add support for MSC >> >> > frame decoding >> >> > >> >> > Hi Gowtham, >> >> > >> >> > On Tue, Dec 2, 2014 at 11:37 AM, Gowtham Anandha Babu >> >> > <gowtham.ab@xxxxxxxxxxx> wrote: >> >> > > Changes made to decode MSC frame in RFCOMM for btmon. >> >> > > >> >> > > RFCOMM: Unnumbered Info with Header Check (UIH)(0xef) >> >> > > Address: 0x01 cr 0 dlci 0x00 >> >> > > Control: 0xef poll/final 0 >> >> > > Length: 4 >> >> > > FCS: 0xaa >> >> > > MCC Message type: Modem Status Command CMD(0x38) >> >> > > Length: 2 >> >> > > dlci 32 >> >> > > fc 0 rtc 1 rtr 1 ic 0 dv 1 >> >> > > --- >> >> > > monitor/rfcomm.c | 76 >> >> > > ++++++++++++++++++++++++++++++++++++++++++++++++++----- >> - >> >> > > 1 file changed, 69 insertions(+), 7 deletions(-) >> >> > > >> >> > > diff --git a/monitor/rfcomm.c b/monitor/rfcomm.c index >> >> > > b3db98b..969b29f 100644 >> >> > > --- a/monitor/rfcomm.c >> >> > > +++ b/monitor/rfcomm.c >> >> > > @@ -49,11 +49,24 @@ static char *cr_str[] = { >> >> > > "CMD" >> >> > > }; >> >> > > >> >> > > -#define CR_STR(type) cr_str[GET_CR(type)] -#define >> >> > > GET_LEN8(length) ((length & 0xfe) >> 1) -#define >> >> > > GET_LEN16(length) ((length & 0xfffe) >> >> > > >> 1) >> >> > > -#define GET_CR(type) ((type & 0x02) >> 1) >> >> > > -#define GET_PF(ctr) (((ctr) >> 4) & 0x1) >> >> > > +/* RFCOMM frame parsing macros */ >> >> > > +#define CR_STR(type) cr_str[GET_CR(type)] >> >> > > +#define GET_LEN8(length) ((length & 0xfe) >> 1) >> >> > > +#define GET_LEN16(length) ((length & 0xfffe) >> 1) >> >> > > +#define GET_CR(type) ((type & 0x02) >> 1) >> >> > > +#define GET_PF(ctr) (((ctr) >> 4) & 0x1) >> >> > > + >> >> > > +/* MSC macros */ >> >> > > +#define GET_V24_FC(sigs) ((sigs & 0x02) >> 1) >> >> > > +#define GET_V24_RTC(sigs) ((sigs & 0x04) >> 2) >> >> > > +#define GET_V24_RTR(sigs) ((sigs & 0x08) >> 3) >> >> > > +#define GET_V24_IC(sigs) ((sigs & 0x40) >> 6) >> >> > > +#define GET_V24_DV(sigs) ((sigs & 0x80) >> 7) >> >> > > + >> >> > > +#define GET_BRK_SIG1(sigs) ((sigs & 0x02) >> 1) >> >> > > +#define GET_BRK_SIG2(sigs) ((sigs & 0x04) >> 2) >> >> > > +#define GET_BRK_SIG3(sigs) ((sigs & 0x08) >> 3) >> >> > > +#define GET_BRK_SIG_LEN(sigs) ((sigs & 0xf0) >> 4) >> >> > > >> >> > > struct rfcomm_lhdr { >> >> > > uint8_t address; >> >> > > @@ -63,6 +76,12 @@ struct rfcomm_lhdr { >> >> > > uint8_t credits; /* only for UIH frame */ } >> >> > > __attribute__((packed)); >> >> > > >> >> > > +struct rfcomm_lmsc { >> >> > > + uint8_t dlci; >> >> > > + uint8_t v24_sig; >> >> > > + uint8_t break_sig; >> >> > > +} __attribute__((packed)); >> >> > > + >> >> > > struct rfcomm_lmcc { >> >> > > uint8_t type; >> >> > > uint16_t length; >> >> > > @@ -92,6 +111,43 @@ static void print_rfcomm_hdr(struct >> >> rfcomm_frame >> >> > *rfcomm_frame, uint8_t indent) >> >> > > print_field("%*cFCS: 0x%2.2x", indent, ' ', hdr.fcs); } >> >> > > >> >> > > +static inline bool mcc_msc(struct rfcomm_frame *rfcomm_frame, >> >> > > +uint8_t >> >> > > +indent) { >> >> > > + struct l2cap_frame *frame = &rfcomm_frame->l2cap_frame; >> >> > > + struct rfcomm_lmsc msc; >> >> > > + >> >> > > + if (!l2cap_frame_get_u8(frame, &msc.dlci)) >> >> > > + return false; >> >> > > + >> >> > > + print_field("%*cdlci %d ", indent, ' ', >> >> > > + RFCOMM_GET_DLCI(msc.dlci)); >> >> > > + >> >> > > + if (!l2cap_frame_get_u8(frame, &msc.v24_sig)) >> >> > > + return false; >> >> > > + >> >> > > + /* v24 control signals */ >> >> > > + print_field("%*cfc %d rtc %d rtr %d ic %d dv %d", indent, ' ', >> >> > > + GET_V24_FC(msc.v24_sig), GET_V24_RTC(msc.v24_sig), >> >> > > + GET_V24_RTR(msc.v24_sig), GET_V24_IC(msc.v24_sig), >> >> > > + GET_V24_DV(msc.v24_sig)); >> >> > > + >> >> > > + if (frame->size < 2) >> >> > > + goto done; >> >> > > + >> >> > > + /* break signals (optional) */ >> >> > > + >> >> > > + if (!l2cap_frame_get_u8(frame, &msc.break_sig)) >> >> > > + return false; >> >> > > + >> >> > > + printf("%2.2x", msc.break_sig); >> >> > >> >> > Im very suspicious the printf above will break indentation, you >> >> > better add a frame that does exercise this code to make sure it is not >> happening. >> >> > >> >> >> >> That printf was added to cross check the break signals. >> >> I Forgot to remove that line. Will update in v2. >> >> >> > >> > I tried testing with many test cases, not able to capture the break signals. >> > Any suggestions to capture the break signals? >> > Btw the implementation here is exactly same as in hcidump. >> >> Perhaps you can try some test case with PTS, please check the TS if there is a >> TC that tests break signals. >> > > I referred the RFCOMM TS and tried all test cases for RFCOMM in PTS, still not able to capture the break signals. > In the RFCOMM specs also, break signal fields are not explained much. > Meanwhile I tried executing the MAP, PBAP, OPP, FTP connection establishment test cases, nothing worked out. > > Since this is optional, can we skip this (break signal decoding) for now? Or what do you think? Then skip it and add a TODO to the code. -- Luiz Augusto von Dentz -- To unsubscribe from this list: send the line "unsubscribe linux-bluetooth" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
