Hi On Wed, Jul 25, 2012 at 6:33 PM, Michal Nazarewicz <mina86@xxxxxxxxxx> wrote: > On Wed, 25 Jul 2012 14:53:00 +0200, Rajaram REGUPATHY > <ragupathy.rajaram@xxxxxxxxxxxxxx> wrote: >> >> The short_not_ok field is used by class drivers to indicate udc whether >> short packet is expected during a particular transfer. >> In case of mass storage, during command and status phase this field is set >> as false and set to true during data phase. >> musb driver uses this field to decide whether to program DMA for mode1. >> This code is essential for musb driver to program DMA. > > > There's one thing I don't get. The message talks about musb but the code > checks for non Super Speed devices. So maybe the code is correct, maybe > it's not, but the message does not really explain it (at least to me). > Please let me know if this thread sets the context ? http://www.spinics.net/lists/linux-usb/msg64938.html > (Also, you probably should wrap the message before 80th column.) > > >> Signed-off-by: Balakumar Rajendran <balakumar.rajendran@xxxxxxxxxxxxxx> >> Signed-off-by: Rajaram R <ragupathy.rajaram@xxxxxxxxxxxxxx> >> --- >> drivers/usb/gadget/f_mass_storage.c | 9 +++++++++ >> 1 files changed, 9 insertions(+), 0 deletions(-) >> >> diff --git a/drivers/usb/gadget/f_mass_storage.c >> b/drivers/usb/gadget/f_mass_storage.c >> index f67b453..db8bf4a 100644 >> --- a/drivers/usb/gadget/f_mass_storage.c >> +++ b/drivers/usb/gadget/f_mass_storage.c >> @@ -878,6 +878,7 @@ static int do_write(struct fsg_common *common) >> unsigned int amount; >> ssize_t nwritten; >> int rc; >> + struct usb_gadget *gadget = common->cdev->gadget; >> if (curlun->ro) { >> curlun->sense_data = SS_WRITE_PROTECTED; @@ -960,6 +961,8 >> @@ static int do_write(struct fsg_common *common) >> * the bulk-out maxpacket size. >> */ >> set_bulk_out_req_length(common, bh, amount); >> + if (!gadget_is_superspeed(gadget)) >> + bh->outreq->short_not_ok = 1; >> if (!start_out_transfer(common, bh)) >> /* Dunno what to do if common->fsg is NULL >> */ >> return -EIO; >> @@ -1584,6 +1587,7 @@ static int throw_away_data(struct fsg_common >> *common) >> struct fsg_buffhd *bh; >> u32 amount; >> int rc; >> + struct usb_gadget *gadget = common->cdev->gadget; >> for (bh = common->next_buffhd_to_drain; >> bh->state != BUF_STATE_EMPTY || common->usb_amount_left > 0; >> @@ -1617,6 +1621,8 @@ static int throw_away_data(struct fsg_common *common) >> * the bulk-out maxpacket size. >> */ >> set_bulk_out_req_length(common, bh, amount); >> + if (!gadget_is_superspeed(gadget)) >> + bh->outreq->short_not_ok = 1; >> if (!start_out_transfer(common, bh)) >> /* Dunno what to do if common->fsg is NULL >> */ >> return -EIO; >> @@ -2292,6 +2298,7 @@ static int get_next_command(struct fsg_common >> *common) { >> struct fsg_buffhd *bh; >> int rc = 0; >> + struct usb_gadget *gadget = common->cdev->gadget; >> /* Wait for the next buffer to become available */ >> bh = common->next_buffhd_to_fill; >> @@ -2303,6 +2310,8 @@ static int get_next_command(struct fsg_common >> *common) >> /* Queue a request to read a Bulk-only CBW */ >> set_bulk_out_req_length(common, bh, US_BULK_CB_WRAP_LEN); >> + if (!gadget_is_superspeed(gadget)) >> + bh->outreq->short_not_ok = 0; >> if (!start_out_transfer(common, bh)) >> /* Don't know what to do if common->fsg is NULL */ >> return -EIO; > > > -- > Best regards, _ _ > .o. | Liege of Serenely Enlightened Majesty of o' \,=./ `o > ..o | Computer Science, Michał “mina86” Nazarewicz (o o) > ooo +----<email/xmpp: mpn@xxxxxxxxxx>--------------ooO--(_)--Ooo-- > > -- > To unsubscribe from this list: send the line "unsubscribe linux-usb" in > the body of a message to majordomo@xxxxxxxxxxxxxxx > More majordomo info at http://vger.kernel.org/majordomo-info.html -- To unsubscribe from this list: send the line "unsubscribe linux-usb" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
