From mboxrd@z Thu Jan 1 00:00:00 1970 From: John McKell Subject: [PATCH] DVD-R capability flag set incorrectly, /proc formatting fix Date: 09 Feb 2004 16:26:01 -0700 Sender: linux-scsi-owner@vger.kernel.org Message-ID: <1076369160.3594.6.camel@lintest.iomegacorp.com> Mime-Version: 1.0 Content-Type: text/plain Content-Transfer-Encoding: 7bit Return-path: Received: from email-out1.iomega.com ([147.178.1.82]:63205 "EHLO email.iomega.com") by vger.kernel.org with ESMTP id S265378AbUBIX0C (ORCPT ); Mon, 9 Feb 2004 18:26:02 -0500 List-Id: linux-scsi@vger.kernel.org To: Jens Axboe Cc: linux-scsi@vger.kernel.org This patch for scsi/sr.c and cdrom/cdrom.c persuades /proc/sys/dev/cdrom/info to report that connecting a drive via USB rather than ATAPI in fact does not make it able to write DVD-R. In linux-2.6.2 without this patch, when sr0 and hdd are the same type of device connected via USB and ATAPI respectively, I see: $ cat /proc/sys/dev/cdrom/info: drive name: sr1 sr0 hdd ... Can write CD-R: 1 0 0 Can write CD-RW: 1 0 0 Can read DVD: 0 0 0 Can write DVD-R: 1 1 0 Can write DVD-RAM: 0 0 0 Can read MRW: 0 0 0 Can write MRW: 0 0 0 With this patch applied, instead I see: $ cat /proc/sys/dev/cdrom/info: drive name: sr1 sr0 hdd ... Can write CD-R: 1 0 0 Can write CD-RW: 1 0 0 Can read DVD: 0 0 0 Can write DVD-R: 0 0 0 Can write DVD-RAM: 0 0 0 Can read MRW: 0 0 0 Can write MRW: 0 0 0 The sr1 device in particular is an ordinary CD-RW that in fact cannot write DVD-R. While messing with this code, I also thought to tweak the /proc formatting to align the tabbed columns. ---John McKell, Iomega Corp diff -Nurp linux-2.6.2/drivers/scsi/sr.c linux/drivers/scsi/sr.c --- linux-2.6.2/drivers/scsi/sr.c 2004-02-03 20:43:19.000000000 -0700 +++ linux/drivers/scsi/sr.c 2004-02-09 13:59:10.000000000 -0700 @@ -795,10 +795,9 @@ static void get_capabilities(struct scsi if ((buffer[n + 2] & 0x8) == 0) /* not a DVD drive */ cd->cdi.mask |= CDC_DVD; - if ((buffer[n + 3] & 0x20) == 0) { + if ((buffer[n + 3] & 0x20) == 0) /* can't write DVD-RAM media */ cd->cdi.mask |= CDC_DVD_RAM; - } else if ((buffer[n + 3] & 0x10) == 0) /* can't write DVD-R media */ cd->cdi.mask |= CDC_DVD_R; diff -Nurp linux-2.6.2/drivers/cdrom/cdrom.c linux/drivers/cdrom/cdrom.c --- linux-2.6.2/drivers/cdrom/cdrom.c 2004-02-05 14:30:46.000000000 -0700 +++ linux/drivers/cdrom/cdrom.c 2004-02-09 13:58:21.000000000 -0700 @@ -2740,13 +2740,13 @@ int cdrom_sysctl_info(ctl_table *ctl, in for (cdi=topCdromPtr;cdi!=NULL;cdi=cdi->next) pos += sprintf(info+pos, "\t%d", CDROM_CAN(CDC_DVD_RAM) != 0); - pos += sprintf(info+pos, "\nCan read MRW:"); + pos += sprintf(info+pos, "\nCan read MRW:\t"); for (cdi=topCdromPtr;cdi!=NULL;cdi=cdi->next) - pos += sprintf(info+pos, "\t\t%d", CDROM_CAN(CDC_MRW) != 0); + pos += sprintf(info+pos, "\t%d", CDROM_CAN(CDC_MRW) != 0); - pos += sprintf(info+pos, "\nCan write MRW:"); + pos += sprintf(info+pos, "\nCan write MRW:\t"); for (cdi=topCdromPtr;cdi!=NULL;cdi=cdi->next) - pos += sprintf(info+pos, "\t\t%d", CDROM_CAN(CDC_MRW_W) != 0); + pos += sprintf(info+pos, "\t%d", CDROM_CAN(CDC_MRW_W) != 0); strcpy(info+pos,"\n\n");