| Message ID | 20220124160150.19499-1-quic_jackp@quicinc.com |
|---|---|
| State | New |
| Headers | show |
| Series | [v4] usb: gadget: f_mass_storage: Make CD-ROM emulation work with Mac OS-X | expand |
On Mon, Jan 24, 2022 at 08:01:50AM -0800, Jack Pham wrote: > From: Roger Quadros <roger.quadros@nokia.com> > > Mac OS-X expects CD-ROM TOC in raw format (i.e. format:2). It also > sends the READ_TOC CDB in old style SFF8020i format. i.e. 2 format bits > are encoded in MSBs of CDB byte 9. > > This patch will enable CD-ROM emulation to work with Mac OS-X. Tested on > Mac OS X v10.6.3. > > Signed-off-by: Roger Quadros <roger.quadros@nokia.com> > Signed-off-by: Jack Pham <quic_jackp@quicinc.com> > --- > v4: Updated return length as I had inadvertently applied an earlier version of > Roger's patch which had the same mistake [2] Hi Alan, if this looks fine to you would you please mind providing your Acked-by again? Also, if there are no objections, I think this patch can qualify as a bugfix and I can send a v5 Cc'ed to stable with a Fixes tag of commit d5e2b67aae79 ("USB: g_mass_storage: template f_mass_storage.c file created") -- basically this has been around for as long as f_mass_storage.c itself (if not even before when CD-ROM emulation was first introduced to the former file_storage gadget). Thanks, Jack
On Tue, Jan 25, 2022 at 05:21:54PM -0800, Jack Pham wrote: > On Mon, Jan 24, 2022 at 08:01:50AM -0800, Jack Pham wrote: > > From: Roger Quadros <roger.quadros@nokia.com> > > > > Mac OS-X expects CD-ROM TOC in raw format (i.e. format:2). It also > > sends the READ_TOC CDB in old style SFF8020i format. i.e. 2 format bits > > are encoded in MSBs of CDB byte 9. > > > > This patch will enable CD-ROM emulation to work with Mac OS-X. Tested on > > Mac OS X v10.6.3. > > > > Signed-off-by: Roger Quadros <roger.quadros@nokia.com> > > Signed-off-by: Jack Pham <quic_jackp@quicinc.com> > > --- > > v4: Updated return length as I had inadvertently applied an earlier version of > > Roger's patch which had the same mistake [2] > > Hi Alan, if this looks fine to you would you please mind providing your > Acked-by again? Sure, this is good, a simple fix to the earlier version of the patch. In fact, I should have noticed the wrong length value while reading it. Acked-by: Alan Stern <stern@rowland.harvard.edu> > Also, if there are no objections, I think this patch can qualify as a > bugfix and I can send a v5 Cc'ed to stable with a Fixes tag of commit > d5e2b67aae79 ("USB: g_mass_storage: template f_mass_storage.c file > created") -- basically this has been around for as long as > f_mass_storage.c itself (if not even before when CD-ROM emulation was > first introduced to the former file_storage gadget). Whether to call it a bug fix is questionable, because this interface never worked with Mac OSX. But if you want it to be merged into the -stable kernels, I have no objection. Greg KH may not agree... Alan Stern
On Tue, Jan 25, 2022 at 05:21:54PM -0800, Jack Pham wrote: > On Mon, Jan 24, 2022 at 08:01:50AM -0800, Jack Pham wrote: > > From: Roger Quadros <roger.quadros@nokia.com> > > > > Mac OS-X expects CD-ROM TOC in raw format (i.e. format:2). It also > > sends the READ_TOC CDB in old style SFF8020i format. i.e. 2 format bits > > are encoded in MSBs of CDB byte 9. > > > > This patch will enable CD-ROM emulation to work with Mac OS-X. Tested on > > Mac OS X v10.6.3. > > > > Signed-off-by: Roger Quadros <roger.quadros@nokia.com> > > Signed-off-by: Jack Pham <quic_jackp@quicinc.com> > > --- > > v4: Updated return length as I had inadvertently applied an earlier version of > > Roger's patch which had the same mistake [2] > > Hi Alan, if this looks fine to you would you please mind providing your > Acked-by again? > > Also, if there are no objections, I think this patch can qualify as a > bugfix and I can send a v5 Cc'ed to stable with a Fixes tag of commit > d5e2b67aae79 ("USB: g_mass_storage: template f_mass_storage.c file > created") -- basically this has been around for as long as > f_mass_storage.c itself (if not even before when CD-ROM emulation was > first introduced to the former file_storage gadget). It's a new feature, not a bugfix :)
diff --git a/drivers/usb/gadget/function/f_mass_storage.c b/drivers/usb/gadget/function/f_mass_storage.c index 752439690fda..988cbc8cec7a 100644 --- a/drivers/usb/gadget/function/f_mass_storage.c +++ b/drivers/usb/gadget/function/f_mass_storage.c @@ -1188,6 +1188,8 @@ static int do_read_toc(struct fsg_common *common, struct fsg_buffhd *bh) int msf = common->cmnd[1] & 0x02; int start_track = common->cmnd[6]; u8 *buf = (u8 *)bh->buf; + u8 format; + int i, len; if ((common->cmnd[1] & ~0x02) != 0 || /* Mask away MSF */ start_track > 1) { @@ -1195,18 +1197,62 @@ static int do_read_toc(struct fsg_common *common, struct fsg_buffhd *bh) return -EINVAL; } - memset(buf, 0, 20); - buf[1] = (20-2); /* TOC data length */ - buf[2] = 1; /* First track number */ - buf[3] = 1; /* Last track number */ - buf[5] = 0x16; /* Data track, copying allowed */ - buf[6] = 0x01; /* Only track is number 1 */ - store_cdrom_address(&buf[8], msf, 0); + format = common->cmnd[2] & 0xf; + /* + * Check if CDB is old style SFF-8020i + * i.e. format is in 2 MSBs of byte 9 + * Mac OS-X host sends us this. + */ + if (format == 0) + format = (common->cmnd[9] >> 6) & 0x3; + + switch (format) { + case 0: + /* Formatted TOC */ + len = 4 + 2*8; /* 4 byte header + 2 descriptors */ + memset(buf, 0, len); + buf[1] = len - 2; /* TOC Length excludes length field */ + buf[2] = 1; /* First track number */ + buf[3] = 1; /* Last track number */ + buf[5] = 0x16; /* Data track, copying allowed */ + buf[6] = 0x01; /* Only track is number 1 */ + store_cdrom_address(&buf[8], msf, 0); + + buf[13] = 0x16; /* Lead-out track is data */ + buf[14] = 0xAA; /* Lead-out track number */ + store_cdrom_address(&buf[16], msf, curlun->num_sectors); + return len; + + case 2: + /* Raw TOC */ + len = 4 + 3*11; /* 4 byte header + 3 descriptors */ + memset(buf, 0, len); /* Header + A0, A1 & A2 descriptors */ + buf[1] = len - 2; /* TOC Length excludes length field */ + buf[2] = 1; /* First complete session */ + buf[3] = 1; /* Last complete session */ + + buf += 4; + /* fill in A0, A1 and A2 points */ + for (i = 0; i < 3; i++) { + buf[0] = 1; /* Session number */ + buf[1] = 0x16; /* Data track, copying allowed */ + /* 2 - Track number 0 -> TOC */ + buf[3] = 0xA0 + i; /* A0, A1, A2 point */ + /* 4, 5, 6 - Min, sec, frame is zero */ + buf[8] = 1; /* Pmin: last track number */ + buf += 11; /* go to next track descriptor */ + } + buf -= 11; /* go back to A2 descriptor */ - buf[13] = 0x16; /* Lead-out track is data */ - buf[14] = 0xAA; /* Lead-out track number */ - store_cdrom_address(&buf[16], msf, curlun->num_sectors); - return 20; + /* For A2, 7, 8, 9, 10 - zero, Pmin, Psec, Pframe of Lead out */ + store_cdrom_address(&buf[7], msf, curlun->num_sectors); + return len; + + default: + /* Multi-session, PMA, ATIP, CD-TEXT not supported/required */ + curlun->sense_data = SS_INVALID_FIELD_IN_CDB; + return -EINVAL; + } } static int do_mode_sense(struct fsg_common *common, struct fsg_buffhd *bh) @@ -1944,7 +1990,7 @@ static int do_scsi_command(struct fsg_common *common) common->data_size_from_cmnd = get_unaligned_be16(&common->cmnd[7]); reply = check_command(common, 10, DATA_DIR_TO_HOST, - (7<<6) | (1<<1), 1, + (0xf<<6) | (3<<1), 1, "READ TOC"); if (reply == 0) reply = do_read_toc(common, bh);