Return-Path: MIME-Version: 1.0 In-Reply-To: <000201d00e2c$c6bed750$543c85f0$@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> Date: Tue, 2 Dec 2014 14:40:33 +0200 Message-ID: Subject: Re: [PATCH 1/5] monitor/rfcomm.c: Add support for MSC frame decoding From: Luiz Augusto von Dentz To: Gowtham Anandha Babu Cc: "linux-bluetooth@vger.kernel.org" , Dmitry Kasatkin , Bharat Panda , cpgs@samsung.com Content-Type: text/plain; charset=UTF-8 Sender: linux-bluetooth-owner@vger.kernel.org List-ID: 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. >> > > + print_field("%*cb1 %d b2 %d b3 %d len %d", indent, ' ', >> > > + GET_BRK_SIG1(msc.break_sig), GET_BRK_SIG2(msc.break_sig), >> > > + GET_BRK_SIG3(msc.break_sig), >> > > + GET_BRK_SIG_LEN(msc.break_sig)); >> > > + >> > > +done: >> > > + return true; >> > > +} >> > > + >> > > struct mcc_data { >> > > uint8_t type; >> > > const char *str; >> > > @@ -151,7 +207,13 @@ static inline bool mcc_frame(struct >> > > rfcomm_frame >> > *rfcomm_frame, uint8_t indent) >> > > print_field("%*cLength: %d", indent+2, ' ', mcc.length); >> > > >> > > rfcomm_frame->mcc = mcc; >> > > - packet_hexdump(frame->data, frame->size); >> > > + >> > > + switch (type) { >> > > + case RFCOMM_MSC: >> > > + return mcc_msc(rfcomm_frame, indent+2); >> > > + default: >> > > + packet_hexdump(frame->data, frame->size); >> > > + } >> > > >> > > return true; >> > > } >> > > @@ -225,7 +287,7 @@ void rfcomm_packet(const struct l2cap_frame >> > > *frame) >> > > >> > > l2cap_frame_pull(&tmp_frame, l2cap_frame, >> > > l2cap_frame->size-1); >> > > >> > > - if(!l2cap_frame_get_u8(&tmp_frame, &hdr.fcs)) >> > > + if (!l2cap_frame_get_u8(&tmp_frame, &hdr.fcs)) >> > > goto fail; >> > > >> > > /* Decoding frame type */ >> > > -- >> > > 1.9.1 >> > > >> > > -- >> > > 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 >> > >> > >> > >> > -- >> > 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 > > Regards, > Gowtham Anandha Babu > -- Luiz Augusto von Dentz