ide-atapi: compute cmd_len based on device type in ide_transfer_pc

There should be no functionality change resulting from this patch.

Signed-off-by: Borislav Petkov <petkovbb@gmail.com>
[bart: move cmd_len check closer to ->output_data() call]
Signed-off-by: Bartlomiej Zolnierkiewicz <bzolnier@gmail.com>

1 files changed, 13 insertions, 1 deletions

diff --git a/drivers/ide/ide-atapi.c b/drivers/ide/ide-atapi.c
index d412bd2bd7fd..5fdcb953fc13 100644
--- a/drivers/ide/ide-atapi.c
+++ b/drivers/ide/ide-atapi.c
@@ -15,6 +15,8 @@
 #define debug_log(fmt, args...) do {} while (0)
 #endif
 
+#define ATAPI_MIN_CDB_BYTES     12
+
 static inline int dev_is_idecd(ide_drive_t *drive)
 {
         return drive->media == ide_cdrom || drive->media == ide_optical;
@@ -492,6 +494,7 @@ static ide_startstop_t ide_transfer_pc(ide_drive_t *drive)
         struct request *rq = hwif->hwgroup->rq;
         ide_expiry_t *expiry;
         unsigned int timeout;
+        int cmd_len;
         ide_startstop_t startstop;
         u8 ireason;
 
@@ -513,9 +516,18 @@ static ide_startstop_t ide_transfer_pc(ide_drive_t *drive)
         if ((ireason & ATAPI_COD) == 0 || (ireason & ATAPI_IO)) {
                 printk(KERN_ERR "%s: (IO,CoD) != (0,1) while issuing "
                                 "a packet command\n", drive->name);
+
                 return ide_do_reset(drive);
         }
 
+        if (dev_is_idecd(drive)) {
+                /* ATAPI commands get padded out to 12 bytes minimum */
+                cmd_len = COMMAND_SIZE(rq->cmd[0]);
+                if (cmd_len < ATAPI_MIN_CDB_BYTES)
+                        cmd_len = ATAPI_MIN_CDB_BYTES;
+        } else
+                cmd_len = ATAPI_MIN_CDB_BYTES;
+
         /*
          * If necessary schedule the packet transfer to occur 'timeout'
          * miliseconds later in ide_delayed_transfer_pc() after the device
@@ -541,7 +553,7 @@ static ide_startstop_t ide_transfer_pc(ide_drive_t *drive)
 
         /* Send the actual packet */
         if ((drive->atapi_flags & IDE_AFLAG_ZIP_DRIVE) == 0)
-                hwif->tp_ops->output_data(drive, NULL, rq->cmd, 12);
+                hwif->tp_ops->output_data(drive, NULL, rq->cmd, cmd_len);
 
         return ide_started;
 }