From 717ff472176c54e90a4074898a59037f9a4791f5 Mon Sep 17 00:00:00 2001 From: Borislav Petkov Date: Thu, 2 Apr 2009 22:21:31 +0200 Subject: [PATCH] ide-atapi: start DMA after issuing a packet command MIME-Version: 1.0 Content-Type: text/plain; charset=utf8 Content-Transfer-Encoding: 8bit upstream commit: 2eba08270990b99fb5429b76ee97184ddd272f7f Apparently¹, some ATAPI devices want to see the packet command first before enabling DMA otherwise they simply hang indefinitely. Reorder the two steps and start DMA only after having issued the command first. [1] http://marc.info/?l=linux-kernel&m=123835520317235&w=2 Signed-off-by: Borislav Petkov Reported-by: Michael Roth Signed-off-by: Bartlomiej Zolnierkiewicz Signed-off-by: Chris Wright --- drivers/ide/ide-atapi.c | 8 ++++---- 1 file changed, 4 insertions(+), 4 deletions(-) diff --git a/drivers/ide/ide-atapi.c b/drivers/ide/ide-atapi.c index 47497f8b4251..53a9e8dd4e07 100644 --- a/drivers/ide/ide-atapi.c +++ b/drivers/ide/ide-atapi.c @@ -568,6 +568,10 @@ static ide_startstop_t ide_transfer_pc(ide_drive_t *drive) : ide_pc_intr), timeout, expiry); + /* Send the actual packet */ + if ((drive->atapi_flags & IDE_AFLAG_ZIP_DRIVE) == 0) + hwif->tp_ops->output_data(drive, NULL, rq->cmd, cmd_len); + /* Begin DMA, if necessary */ if (dev_is_idecd(drive)) { if (drive->dma) @@ -579,10 +583,6 @@ 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, cmd_len); - return ide_started; } -- 2.39.5