Return-Path: From: Gowtham Anandha Babu To: 'Luiz Augusto von Dentz' Cc: linux-bluetooth@vger.kernel.org, 'Dmitry Kasatkin' , 'Bharat Panda' , cpgs@samsung.com References: <1417513057-16037-1-git-send-email-gowtham.ab@samsung.com> <1417513057-16037-2-git-send-email-gowtham.ab@samsung.com> <000201d00e2c$c6bed750$543c85f0$@samsung.com> <000601d00e3d$d5ca4020$815ec060$@samsung.com> In-reply-to: Subject: RE: [PATCH 1/5] monitor/rfcomm.c: Add support for MSC frame decoding Date: Wed, 03 Dec 2014 18:32:10 +0530 Message-id: <002001d00ef9$74a2b450$5de81cf0$@samsung.com> MIME-version: 1.0 Content-type: text/plain; charset=utf-8 Sender: linux-bluetooth-owner@vger.kernel.org List-ID: Hi Luiz, > -----Original Message----- > From: linux-bluetooth-owner@vger.kernel.org [mailto:linux-bluetooth- > owner@vger.kernel.org] On Behalf Of Luiz Augusto von Dentz > Sent: Tuesday, December 02, 2014 8:41 PM > To: Gowtham Anandha Babu > Cc: linux-bluetooth@vger.kernel.org; Dmitry Kasatkin; Bharat Panda; > cpgs@samsung.com > Subject: Re: [PATCH 1/5] monitor/rfcomm.c: Add support for MSC frame > decoding > > Hi Gowtham, > > On Tue, Dec 2, 2014 at 4:39 PM, Gowtham Anandha Babu > wrote: > > Hi Luiz, > > > >> -----Original Message----- > >> From: linux-bluetooth-owner@vger.kernel.org [mailto:linux-bluetooth- > >> owner@vger.kernel.org] On Behalf Of Luiz Augusto von Dentz > >> Sent: Tuesday, December 02, 2014 6:11 PM > >> To: Gowtham Anandha Babu > >> Cc: linux-bluetooth@vger.kernel.org; Dmitry Kasatkin; Bharat Panda; > >> cpgs@samsung.com > >> 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 > >> wrote: > >> > Hi Luiz, > >> > > >> >> -----Original Message----- > >> >> From: Gowtham Anandha Babu [mailto:gowtham.ab@samsung.com] > >> >> Sent: Tuesday, December 02, 2014 4:30 PM > >> >> To: 'Luiz Augusto von Dentz' > >> >> Cc: 'linux-bluetooth@vger.kernel.org'; 'Dmitry Kasatkin'; 'Bharat > >> >> Panda'; 'cpgs@samsung.com' > >> >> Subject: RE: [PATCH 1/5] monitor/rfcomm.c: Add support for MSC > >> >> frame decoding > >> >> > >> >> Hi Luiz, > >> >> > >> >> > -----Original Message----- > >> >> > From: linux-bluetooth-owner@vger.kernel.org > >> >> > [mailto:linux-bluetooth- owner@vger.kernel.org] On Behalf Of > >> >> > Luiz Augusto von Dentz > >> >> > Sent: Tuesday, December 02, 2014 4:22 PM > >> >> > To: Gowtham Anandha Babu > >> >> > Cc: linux-bluetooth@vger.kernel.org; Dmitry Kasatkin; Bharat > >> >> > Panda; cpgs@samsung.com > >> >> > 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 > >> >> > 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. > I skipped this for now and updated the TODO in v1 and submitted the same. Please have a look at it. > > -- > Luiz Augusto von Dentz > -- > To unsubscribe from this list: send the line "unsubscribe linux-bluetooth" in > the body of a message to majordomo@vger.kernel.org More majordomo > info at http://vger.kernel.org/majordomo-info.html Regards, Gowtham Anandha Babu