diff options
author | Benjamin Herrenschmidt <benh@kernel.crashing.org> | 2009-10-13 08:53:47 +0400 |
---|---|---|
committer | Greg Kroah-Hartman <gregkh@suse.de> | 2009-10-15 01:54:44 +0400 |
commit | b8430e1b82b7e514d76a88eb70a7d8831d50df1e (patch) | |
tree | 8be6895f39a120d4919a543e9a3c39a6917bf350 /drivers | |
parent | 36f21329d217016f0f212f0752ae595b4a76754d (diff) | |
download | linux-b8430e1b82b7e514d76a88eb70a7d8831d50df1e.tar.xz |
usb-storage: Workaround devices with bogus sense size
usb-storage: Workaround devices with bogus sense size
Some devices, such as Huawei E169, advertise more than the standard
amount of sense data, causing us to set US_FL_SANE_SENSE, assuming
they support it. However, they subsequently fail the request sense
with that size.
This works around it generically. When a sense request fails due to
a device returning an error, US_FL_SANE_SENSE was set, and that sense
request used a larger sense size, we retry with a smaller size before
giving up.
Based on an original patch by Ben Efros <ben@pc-doctor.com>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Acked-by: Alan Stern <stern@rowland.harvard.edu>
Cc: stable <stable@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
Diffstat (limited to 'drivers')
-rw-r--r-- | drivers/usb/storage/transport.c | 17 |
1 files changed, 16 insertions, 1 deletions
diff --git a/drivers/usb/storage/transport.c b/drivers/usb/storage/transport.c index 3a4fb023af72..589f6b4404f0 100644 --- a/drivers/usb/storage/transport.c +++ b/drivers/usb/storage/transport.c @@ -696,7 +696,7 @@ void usb_stor_invoke_transport(struct scsi_cmnd *srb, struct us_data *us) /* device supports and needs bigger sense buffer */ if (us->fflags & US_FL_SANE_SENSE) sense_size = ~0; - +Retry_Sense: US_DEBUGP("Issuing auto-REQUEST_SENSE\n"); scsi_eh_prep_cmnd(srb, &ses, NULL, 0, sense_size); @@ -720,6 +720,21 @@ void usb_stor_invoke_transport(struct scsi_cmnd *srb, struct us_data *us) srb->result = DID_ABORT << 16; goto Handle_Errors; } + + /* Some devices claim to support larger sense but fail when + * trying to request it. When a transport failure happens + * using US_FS_SANE_SENSE, we always retry with a standard + * (small) sense request. This fixes some USB GSM modems + */ + if (temp_result == USB_STOR_TRANSPORT_FAILED && + (us->fflags & US_FL_SANE_SENSE) && + sense_size != US_SENSE_SIZE) { + US_DEBUGP("-- auto-sense failure, retry small sense\n"); + sense_size = US_SENSE_SIZE; + goto Retry_Sense; + } + + /* Other failures */ if (temp_result != USB_STOR_TRANSPORT_GOOD) { US_DEBUGP("-- auto-sense failure\n"); |