| Message ID | 20220624021916.318067-1-neal_liu@aspeedtech.com |
|---|---|
| State | New |
| Headers | show |
| Series | [v2] usb: gadget: f_mass_storage: Make CD-ROM emulation works with Windows OS | expand |
On Mon, Jun 27, 2022 at 02:56:40AM +0000, Neal Liu wrote: > > On Fri, Jun 24, 2022 at 10:19:16AM +0800, Neal Liu wrote: > > > Add read TOC with format 1 to support CD-ROM emulation with Windows > > > OS. > > > This patch is tested on Windows OS Server 2019. > > > > > > Signed-off-by: Neal Liu <neal_liu@aspeedtech.com> > > > --- > > > drivers/usb/gadget/function/f_mass_storage.c | 5 +++-- > > > 1 file changed, 3 insertions(+), 2 deletions(-) > > > > > > diff --git a/drivers/usb/gadget/function/f_mass_storage.c > > > b/drivers/usb/gadget/function/f_mass_storage.c > > > index 3a77bca0ebe1..9edf76c22605 100644 > > > --- a/drivers/usb/gadget/function/f_mass_storage.c > > > +++ b/drivers/usb/gadget/function/f_mass_storage.c > > > @@ -1209,7 +1209,8 @@ static int do_read_toc(struct fsg_common > > > *common, struct fsg_buffhd *bh) > > > > > > switch (format) { > > > case 0: > > > - /* Formatted TOC */ > > > + case 1: > > > + /* Formatted TOC, Session info */ > > > > This comment is a little misleading. 0 is formatted TOC, and 1 is > > multi-session info. The way you wrote it, it looks like the comment applies to > > both formats. Do it like this: > > > > case 0: /* Formatted TOC */ > > case 1: /* Multi-session info */ > > > > Okay, looks more clear. I'll fix it in next patch. > > > > len = 4 + 2*8; /* 4 byte header + 2 descriptors */ > > > memset(buf, 0, len); > > > buf[1] = len - 2; /* TOC Length excludes length field */ > > > > It looks like you ignored one of the problems I pointed out in my earlier email: > > > > > When format is 1, the driver is supposed to ignore the start_track > > > value. Your patch does not do this. > > > > Please fix this. > > > > Do you mean ignore the "start_track > 1" above? Yes, that's what I mean. > Do this check only for format 0? Or format 0 & 2? According to the MMC spec, the Track/Session Number is ignored for format 1. For format 0 it is valid as a Track Number, and for format 2 it is valid as a Session Number. Therefore it should be checked for formats 0 and 2 but not for format 1. Alan Stern
diff --git a/drivers/usb/gadget/function/f_mass_storage.c b/drivers/usb/gadget/function/f_mass_storage.c index 3a77bca0ebe1..9edf76c22605 100644 --- a/drivers/usb/gadget/function/f_mass_storage.c +++ b/drivers/usb/gadget/function/f_mass_storage.c @@ -1209,7 +1209,8 @@ static int do_read_toc(struct fsg_common *common, struct fsg_buffhd *bh) switch (format) { case 0: - /* Formatted TOC */ + case 1: + /* Formatted TOC, Session info */ len = 4 + 2*8; /* 4 byte header + 2 descriptors */ memset(buf, 0, len); buf[1] = len - 2; /* TOC Length excludes length field */ @@ -1250,7 +1251,7 @@ static int do_read_toc(struct fsg_common *common, struct fsg_buffhd *bh) return len; default: - /* Multi-session, PMA, ATIP, CD-TEXT not supported/required */ + /* PMA, ATIP, CD-TEXT not supported/required */ curlun->sense_data = SS_INVALID_FIELD_IN_CDB; return -EINVAL; }
Add read TOC with format 1 to support CD-ROM emulation with Windows OS. This patch is tested on Windows OS Server 2019. Signed-off-by: Neal Liu <neal_liu@aspeedtech.com> --- drivers/usb/gadget/function/f_mass_storage.c | 5 +++-- 1 file changed, 3 insertions(+), 2 deletions(-)