[lkml]   [2002]   [Sep]   [7]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
Messages in this thread
SubjectLite-On cdwriter detected as 12x instead of 40x
I have a LITE-ON LTR-40125W cdwriter, which can write at 40x.
The kernel sees it as 12x. This happens in 2.4.19ac4 up to
2.4.20pre4ac2, I didn't test later kernels due to the instable IDE
situation. It has the latest firmware (WS05) - I'm not sure if bothering
the manufacturer about this is worth it.

If I don't pass the drive on to ide-scsi, and patch
drivers/ide/ide-cd.c with this small patch,

+ /* brain-dead LiteOn model reports itself as 12x */
+ if ((cap != NULL) && (strcmp (drive->id->model, "LITE-ON LTR-40125W") == 0))
+ cap->maxspeed = htons(40 * 176);

all is well, and the kernel reports 40x.

But I can't find out where to put this for the ide-scsi part.
All the probing routines in drivers/scsi/ide-cd.c seem to access some
sort of atapi-buffer that already exists. I can tweak it to display 40x
in the bootup-messages by changing the idescsi_transform_pc? functions
in drivers/scsi/ide-cd.c:

+ if (strcmp (drive->id->model, "LITE-ON LTR-40125W") == 0)
+ {
+ int n = scsi_buf[3] + 4;
+ scsi_buf[n+8] = scsi_buf[n+14] = (u8) ((40 * 176) >> 8);
+ scsi_buf[n+9] = scsi_buf[n+15] = (u8) ((40 * 176) & 0xff);
+ printk("ide-scsi.c: LITE-ON tweak activated\n");
+ }

but that doesn't fool cdrdao nor cdrecord - they still think the drive
is 12x.

Can anyone help me by pointing out where I should tweak the kernel to
get correct results when using ide-scsi with my drive?

Remember, Unix on some machines is nUxi.
GNU/Linux 2.4.19-ac4 SMP/ReiserFS 2x1402 bogomips load av: 0.39 0.28 0.11
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to
More majordomo info at
Please read the FAQ at

 \ /
  Last update: 2005-03-22 13:28    [W:0.026 / U:0.400 seconds]
©2003-2020 Jasper Spaans|hosted at Digital Ocean and TransIP|Read the blog|Advertise on this site