From mboxrd@z Thu Jan 1 00:00:00 1970 From: Hans de Goede Subject: [PATCH resend 1/4] scsi/sr: add no_read_disc_info scsi_device flag Date: Fri, 23 Jul 2010 10:52:51 +0200 Message-ID: <1279875174-2905-1-git-send-email-hdegoede@redhat.com> Return-path: Received: from mx1.redhat.com ([209.132.183.28]:51451 "EHLO mx1.redhat.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1754831Ab0GWItx (ORCPT ); Fri, 23 Jul 2010 04:49:53 -0400 Sender: linux-scsi-owner@vger.kernel.org List-Id: linux-scsi@vger.kernel.org To: James.Bottomley@suse.de, Tejun Heo , Alan Stern , akpm@linux-foundation.org Cc: linux-scsi@vger.kernel.org, linux-usb@vger.kernel.org, Hans de Goede Some USB devices emulate a usb-mass-storage attached (scsi) cdrom device, usually this fake cdrom contains the windows software for the device. While working on supporting Appotech ax3003 based photoframes, which do this I discovered that they will go of into lala land when ever they see a READ_DISC_INFO scsi command. Thus this patch adds a scsi_device flag (which can then be set by the usb-storage driver through an unsual-devs entry), to indicate this, and makes the sr driver honor this flag. I know this sucks, but as discussed on linux-scsi list there is no other way to make this device work properly. Looking at usb traces made under windows, windows never sends a READ_DISC_INFO during normal interactions with a usb cdrom device. So as this cdrom emulation thingie becomes more common we might see more of this problem. Signed-off-by: Hans de Goede --- drivers/scsi/sr.c | 8 +++++++- include/scsi/scsi_device.h | 1 + 2 files changed, 8 insertions(+), 1 deletions(-) diff --git a/drivers/scsi/sr.c b/drivers/scsi/sr.c index 0a90abc..18077b5 100644 --- a/drivers/scsi/sr.c +++ b/drivers/scsi/sr.c @@ -849,10 +849,16 @@ static void get_capabilities(struct scsi_cd *cd) static int sr_packet(struct cdrom_device_info *cdi, struct packet_command *cgc) { + struct scsi_cd *cd = cdi->handle; + struct scsi_device *sdev = cd->device; + + if (cgc->cmd[0] == GPCMD_READ_DISC_INFO && sdev->no_read_disc_info) + return -EDRIVE_CANT_DO_THIS; + if (cgc->timeout <= 0) cgc->timeout = IOCTL_TIMEOUT; - sr_do_ioctl(cdi->handle, cgc); + sr_do_ioctl(cd, cgc); return cgc->stat; } diff --git a/include/scsi/scsi_device.h b/include/scsi/scsi_device.h index d80b6db..e1b2db8 100644 --- a/include/scsi/scsi_device.h +++ b/include/scsi/scsi_device.h @@ -148,6 +148,7 @@ struct scsi_device { unsigned retry_hwerror:1; /* Retry HARDWARE_ERROR */ unsigned last_sector_bug:1; /* do not use multisector accesses on SD_LAST_BUGGY_SECTORS */ + unsigned no_read_disc_info:1; /* Avoid READ_DISC_INFO cmds */ unsigned is_visible:1; /* is the device visible in sysfs */ DECLARE_BITMAP(supported_events, SDEV_EVT_MAXBITS); /* supported events */ -- 1.7.0.1