USB DVD drive connected, but /dev/cdrom and /dev/dvd did not be created

[tatemono]

[my H/W]
         (1) RPi: Raspberry Pi 3 Model B
         (2) USB DVD drive: PIONEER  DVD-RW DVR-XD11T
[O.S.] TC 7.1 beta 4 with the following 3 modifications:
         (1) add "dtparam=audio=on" to config.txt
         (2) comment out "dtparam=i2c=on,spi=on,i2s=on,i2c_vc=on" in config.txt
         (3) tce-load -w -i alsa-config.tcz
-----
After connecting my USB DVD drive with a data CD loaded, the symbolic link /dev/cdrom and /dev/dvd did not be created.

I was sure that TC detected my USB DVD drive because of the messages produced by dmesg.

Code: [Select]

tc@box:/mnt/mmcblk0p2/tce$ dmesg | tail
[ 2319.019433] usb 1-1.5: new high-speed USB device number 5 using dwc_otg
[ 2319.120794] usb 1-1.5: New USB device found, idVendor=08e4, idProduct=016e
[ 2319.120812] usb 1-1.5: New USB device strings: Mfr=1, Product=2, SerialNumber=3
[ 2319.120826] usb 1-1.5: Product: Pioneer external optical drive
[ 2319.120839] usb 1-1.5: Manufacturer: Pioneer Corporation
[ 2319.120851] usb 1-1.5: SerialNumber: NDQC062521WL   
[ 2319.121667] usb-storage 1-1.5:1.0: USB Mass Storage device detected
[ 2319.121990] scsi host1: usb-storage 1-1.5:1.0
[ 2320.120574] scsi 1:0:0:0: CD-ROM            PIONEER  DVD-RW DVR-XD11  1.00 PQ: 0 ANSI: 0
[/font]

I tried to mount the data CD by using /dev/sr0 or /dev/sr1 and failed.

Code: [Select]

tc@box:/mnt/mmcblk0p2/tce$ mkdir /tmp/DATA
tc@box:/mnt/mmcblk0p2/tce$ sudo mount /dev/sr0 /tmp/DATA
mount: /dev/sr0 is not a valid block device
tc@box:/mnt/mmcblk0p2/tce$ sudo mount /dev/sr1 /tmp/DATA
mount: /dev/sr1 is not a valid block device
[/font]

I do not know how to use my USB DVD drive to read the loaded data CD.  Could you please give me some ideas of solving this problem?
Thank you in advance.

[curaga]

There should also be messages like these:

sr 3:0:0:0: [sr0] scsi3-mmc drive: 48x/48x writer dvd-ram cd/rw xa/form2 cdda tray
cdrom: Uniform CD-ROM driver Revision: 3.20
sr 3:0:0:0: Attached scsi CD-ROM sr0

I guess the sr driver - cdrom drive support - is disabled in the pi kernel. It is rather unexpected to use with a pi, to me at least.

[jgrulich]

The DVD drive was identified, but not enumerated as a storage device. You need the driver for it, at least cdrom.ko.gz and may be some scsi, or sometimes firmware.
Search here: http://www.tinycorelinux.net/7.x/armv7/releases/RPi2/src/kernel/4.1.20-piCore_v7+_modules.tar.xz and test.

[tatemono]

I am very thankful to everyone who gave me ideas of solving this problem.

Well, it seems that TC 7.1 beta 4 does not have drivers to support USB DVD drives.  Unfortunately, I do not know how to build the missing drivers from Linux kernel source code.  I have to wait until TC is capable of supporting USB DVD drives.

[bmarkus]

Does it work with Raspbian? If so, can you tell which kernel modules used?

[tatemono]

Does it work with Raspbian?

My USB DVD drive works well with Raspbian.  The version of Raspbian I just tried is "Raspbian Jessie Lite May 2016."

If so, can you tell which kernel modules used?

lsmod did not show sg, sr_mod and cdrom until USB DVD drive was connected.  It seems that sg, sr_mod and cdrom are the CDROM/DVD-related kernel modules.  Please refer to the following commands for details.

/* MY USB DVD DRIVE WAS NOT PLUGGED. */

Code: [Select]

pi@raspberrypi:~ $ lsmod | tee /tmp/LSMOD_BEFORE
Module                  Size  Used by
bnep                   10340  2
hci_uart               17943  1
btbcm                   5929  1 hci_uart
bluetooth             326105  22 bnep,btbcm,hci_uart
brcmfmac              186599  0
brcmutil                5661  1 brcmfmac
cfg80211              427855  1 brcmfmac
rfkill                 16037  4 cfg80211,bluetooth
snd_bcm2835            20511  0
snd_pcm                75698  1 snd_bcm2835
snd_timer              19160  1 snd_pcm
bcm2835_wdt             3225  0
snd                    51844  3 snd_bcm2835,snd_timer,snd_pcm
bcm2835_gpiomem         3040  0
uio_pdrv_genirq         3164  0
uio                     8000  1 uio_pdrv_genirq
ipv6                  347530  30
pi@raspberrypi:~ $ ls -l /dev/{cdrom,dvd,sr*}
ls: cannot access /dev/cdrom: No such file or directory
ls: cannot access /dev/dvd: No such file or directory
ls: cannot access /dev/sr*: No such file or directory
[/font]

/* MY USB DVD DRIVE WAS PLUGGED. */

Code: [Select]

pi@raspberrypi:~ $ dmesg | tail -15
[   12.444506] Bluetooth: BNEP filters: protocol multicast
[   12.444519] Bluetooth: BNEP socket layer initialized
[  151.417491] usb 1-1.5: new high-speed USB device number 4 using dwc_otg
[  151.518853] usb 1-1.5: New USB device found, idVendor=08e4, idProduct=016e
[  151.518875] usb 1-1.5: New USB device strings: Mfr=1, Product=2, SerialNumber=3
[  151.518888] usb 1-1.5: Product: Pioneer external optica\xffffffe2\xffffff81\xffffffac\xffffffe6\xffffff90\xffffff80\xffffffe7\xffffff88\xffffff80\xffffffe6\xffffffa4\xffffff80\xffffffe7\xffffff98\xffffff80\xffffffe6\xffffff94\xffffff80\xffffffe2\xffffff88\xffffff80
[  151.518912] usb 1-1.5: Manufacturer: Pioneer Corporation
[  151.518924] usb 1-1.5: SerialNumber: NDQC062521WL   
[  151.519865] usb-storage 1-1.5:1.0: USB Mass Storage device detected
[  151.522756] scsi host0: usb-storage 1-1.5:1.0
[  152.518639] scsi 0:0:0:0: CD-ROM            PIONEER  DVD-RW DVR-XD11  1.00 PQ: 0 ANSI: 0
[  152.537394] sr 0:0:0:0: [sr0] scsi3-mmc drive: 24x/24x writer dvd-ram cd/rw xa/form2 cdda tray
[  152.537414] cdrom: Uniform CD-ROM driver Revision: 3.20
[  152.538368] sr 0:0:0:0: Attached scsi CD-ROM sr0
[  152.543880] sr 0:0:0:0: Attached scsi generic sg0 type 5
pi@raspberrypi:~ $ ls -l /dev/{cdrom,dvd,sr*}
lrwxrwxrwx 1 root root      3 May 19 15:31 /dev/cdrom -> sr0
lrwxrwxrwx 1 root root      3 May 19 15:31 /dev/dvd -> sr0
brw-rw---- 1 root cdrom 11, 0 May 19 15:31 /dev/sr0
pi@raspberrypi:~ $ lsmod | tee /tmp/LSMOD_AFTER
Module                  Size  Used by
sg                     18319  0
sr_mod                 13220  0
cdrom                  27410  1 sr_mod
bnep                   10340  2
hci_uart               17943  1
btbcm                   5929  1 hci_uart
bluetooth             326105  22 bnep,btbcm,hci_uart
brcmfmac              186599  0
brcmutil                5661  1 brcmfmac
cfg80211              427855  1 brcmfmac
rfkill                 16037  4 cfg80211,bluetooth
snd_bcm2835            20511  0
snd_pcm                75698  1 snd_bcm2835
snd_timer              19160  1 snd_pcm
bcm2835_wdt             3225  0
snd                    51844  3 snd_bcm2835,snd_timer,snd_pcm
bcm2835_gpiomem         3040  0
uio_pdrv_genirq         3164  0
uio                     8000  1 uio_pdrv_genirq
ipv6                  347530  30
pi@raspberrypi:~ $ mkdir /tmp/DATA
pi@raspberrypi:~ $ sudo mount -t iso9660 /dev/cdrom /tmp/DATA
mount: /dev/sr0 is write-protected, mounting read-only
pi@raspberrypi:~ $ mount | grep /tmp/DATA
/dev/sr0 on /tmp/DATA type iso9660 (ro,relatime)
pi@raspberrypi:~ $ diff /tmp/LSMOD_BEFORE /tmp/LSMOD_AFTER
2a3,5
> sg                     18319  0
> sr_mod                 13220  0
> cdrom                  27410  1 sr_mod
[/font]

By the way, I found a difference between Raspbian and TC in /dev/sr*.  In Raspbian, /dev/sr* does not exist until USB DVD drive is connected.  In TC 7.1 beta4, there are /dev/sr0 and /dev/sr1 after booting.

Thank you, bmarkus.

[bmarkus]

sg.ko, sr_mod.ko and cdrom.ko kernel modules are not part of the base but built. For 7.x armv7 you can find them in this file:

http://tinycorelinux.net/7.x/armv7/releases/RPi2/src/kernel/4.1.13-piCore_v7+_modules.tar.xz
 

[jgrulich]

That's what I've stated and wrote before. cdrom and scsi drivers.
BTW, the latest is this: http://tinycorelinux.net/7.x/armv7/releases/RPi2/src/kernel/4.1.20-piCore_v7+_modules.tar.xz
And how to build the extension, look in the wiki, or corebook: http://tinycorelinux.net/book.html.

[tatemono]

sg.ko, sr_mod.ko and cdrom.ko kernel modules are not part of the base but built.

@bmarkus

Being a HTPC is one of the major applications of a RPi.  A DVD/CD-ROM drive is one of the audio/video sources of a HTPC.

Furthermore, USB DVD/CD-ROM drives are not uncommon devices, they are popular.  If TC supports USB DVD/CD-ROM drives, more RPi users can benefit from TC.

Could you please add "USB DVD/CD-ROM drive support issue" to your TO-DO list?

Thank you.

[tatemono]

BTW, the latest is this: http://tinycorelinux.net/7.x/armv7/releases/RPi2/src/kernel/4.1.20-piCore_v7+_modules.tar.xz
And how to build the extension, look in the wiki, or corebook: http://tinycorelinux.net/book.html.

[UPDATE MY LAST POST]

@bmarkus

Thanks to jgrulich's hint, I created TCZ file supporting USB DVD/CD-ROM drive successfully.

If you are too busy to add "USB DVD/CD-ROM drive supprt" to your TO-DO list, it is okay because creating such TCZ file is unexpectedly easy.

For those who need USB DVD/CD-ROM support, please do the following steps.

[1] download 4.1.20-piCore_v7+_modules.tar.xz

Code: [Select]

mkdir /tmp
cd /tmp
wget http://tinycorelinux.net/7.x/armv7/releases/RPi2/src/kernel/4.1.20-piCore_v7+_modules.tar.xz

[2] extract drivers
4 drivers are needed.  isofs.ko is for mounting ISO9660 dics.  The other 3 drivers are for USB DVD/CD-ROM drive.

Code: [Select]

tar /tmp/tJf 4.1.20-piCore_v7+_modules.tar.xz > /tmp/_MODULES
mkdir /tmp/DATA
cd /tmp/DATA
tar xJf /tmp/4.1.20-piCore_v7+_modules.tar.xz `grep sg.ko /tmp/_MODULES`
tar xJf /tmp/4.1.20-piCore_v7+_modules.tar.xz `grep sr_mod.ko /tmp/_MODULES`
tar xJf /tmp/4.1.20-piCore_v7+_modules.tar.xz `grep cdrom.ko /tmp/_MODULES`
tar xJf /tmp/4.1.20-piCore_v7+_modules.tar.xz `grep isofs.ko /tmp/_MODULES`

[3] create TCZ file

Code: [Select]

tce-load -w squashfs-tools.tcz
tce-load -i squashfs-tools.tcz
cd /tmp
mksquashfs DATA /tmp/cdrom_and_isofs_drivers.tcz

[4] update onboot.txt

Code: [Select]

cp -p /tmp/cdrom_and_isofs_drivers.tcz /mnt/mmcblk0p2/tce/optional
echo cdrom_and_isofs_drivers.tcz >> /etc/sysconfig/tcedir/onboot.lst

[5] reboot

---------------------
MANY THANKS TO THOSE WHO REPLIED THIS TOPIC.

[bmarkus]

isofs.ko is provided by filesystems-KERNEL.tcz which must be a dependency of your custom kernel package.

Also follow TC naming standard for kernel modules, add kernel version to identify related kernel version.

[tatemono]

isofs.ko is provided by filesystems-KERNEL.tcz which must be a dependency of your custom kernel package.

Also follow TC naming standard for kernel modules, add kernel version to identify related kernel version.

@bmarkus

I am sorry that I did not know isofs.ko has been provided by filesystems-KERNEL.tcz.

Thank you for pointing out that my custom TCZ filename does not follow TC's naming convention.

Actually, I am a newbie of TC because I did not use it until 2 weeks ago.  So, I still have a lot of things and knowledge about TC to learn.  Thank you for giving me information and advice.