USB: mass storage: emulation of sat scsi_pass_thru with ATACB
I have got a cypress usb-ide bridge and I would like to tune or monitor
my disk with tools like hdparm, hddtemp or smartctl.
My controller support a way to send raw ATA command to the disk with
something call atacb (see
http://download.cypress.com.edgesuite.net/design_resources/datasheets/contents/cy7c68300c_8.pdf).
Atacb support can be added for each application, but there is some disadvantages :
- all application need to be patched
- A race is possible if there other accesses, because the emulation can
be split in 2 atacb scsi transactions. One for sending the command, one
for reading the register (if ck_cond is set).
I have implemented the emulation in usb-storage with a special proto_handler,
and an unsual entry.
Signed-off-by: Matthieu CASTET <castet.matthieu@free.fr>
Signed-off-by: Matthew Dharm <mdharm-usb@one-eyed-alien.net>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
diff --git a/drivers/usb/storage/usb.c b/drivers/usb/storage/usb.c
index ac6114e..f59593d 100644
--- a/drivers/usb/storage/usb.c
+++ b/drivers/usb/storage/usb.c
@@ -101,6 +101,9 @@
#ifdef CONFIG_USB_STORAGE_KARMA
#include "karma.h"
#endif
+#ifdef CONFIG_USB_STORAGE_CYPRESS_ATACB
+#include "cypress_atacb.h"
+#endif
/* Some informational data */
MODULE_AUTHOR("Matthew Dharm <mdharm-usb@one-eyed-alien.net>");
@@ -708,6 +711,13 @@
break;
#endif
+#ifdef CONFIG_USB_STORAGE_CYPRESS_ATACB
+ case US_SC_CYP_ATACB:
+ us->protocol_name = "Transparent SCSI with Cypress ATACB";
+ us->proto_handler = cypress_atacb_passthrough;
+ break;
+#endif
+
default:
return -EIO;
}