Your advice to use O_NONBLOCK upon opening /dev/cdrom
fixed the cd audio player program, thanks.
But trying to set the CD-ROM spindown time I faced some other problems.
First, I mentioned my cdprobe program in my previous mail.
In that program, I used
result = ioctl(fd, CDROM_GET_CAPABILITY); [1]
to get the capabilities of the drive. Experimenting with
CDROMGETSPINDOWN and CDROMSETSPINDOWN ioctls, I discovered
that to get the spindown setting I have to use
result = ioctl(fd, CDROMGETSPINDOWN, &spindown); [2]
instead of
result = ioctl(fd, CDROMGETSPINDOWN);
and this annoys me a little. Why do the interfaces of [1]
and [2] differ? They both return a single numeric value
when they succeed. They should look and work the same,
shouldn't they?
Second, when I try to set the spindown setting in my program,
ftp://ftp.externet.hu/pub/people/zboszor/cdspin.c with
result = ioctl(fd, CDROMSETSPINDOWN, newspindown);
in line 47 I get the following error:
[root@boszi 3]# ./cdspin 15
Trying to get spindown setting... success, 9
Trying to set spindown setting to 15... failure: Bad address
If I change it to
result = ioctl(fd, CDROMSETSPINDOWN, &newspindown);
then I get the following error:
[root@boszi 3]# ./cdspin 15
Trying to get spindown setting... success, 9
hdd: cdrom_pc_intr: Drive wants to transfer data the wrong way!
hdd: packet command error: status=0x51 { DriveReady SeekComplete Error }
hdd: packet command error: error=0x50
ATAPI device hdd:
Error: Illegal request -- (Sense key=0x05)
Invalid field in parameter list -- (asc=0x26, ascq=0x00)
The failed "Mode Select 10" packet command was:
"55 10 0d 00 00 00 00 00 10 00 00 00 "
Error in command data byte 36029
Trying to set spindown setting to 15... failure: Input/output error
Which would be the correct code? I suppose that the first one
would be the correct one because in my cdprobe program the CD-ROM
speed setting is done this way:
result = ioctl(fd, CDROM_SELECT_SPEED, speed);
and this succeeds.
Third, I asked whether the statements about the spindown settings
in the hdparm manpage are correct or not. This manpage talks about
settings in the range 0 ... 255. But ide-cd.c uses only the lower
4 bits of what it gets (in both CDROMSETSPINDOWN and CDROMGETSPINDOWN).
So the hdparm works in another way than ide-cd.c and the settings
for hdparm aren't valid for ide-cd. Now, will you please explain
what the settings (0 ... 15) mean for the ide-cd ioctls?
All of these were experienced on 2.3.16 patch with both of your
cdrom fixes.
Best regards,
Zoltan Boszormenyi
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