tjh.dev
Linux kernel mirror (for testing)
git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git
kernel
os
linux
1/proc/sound, /dev/sndstat
2-------------------------
3
4/proc/sound and /dev/sndstat is not supported by the
5driver. To find out whether the driver succeeded loading,
6check the kernel log (dmesg).
7
8
9ALaw/uLaw sample formats
10------------------------
11
12This driver does not support the ALaw/uLaw sample formats.
13ALaw is the default mode when opening a sound device
14using OSS/Free. The reason for the lack of support is
15that the hardware does not support these formats, and adding
16conversion routines to the kernel would lead to very ugly
17code in the presence of the mmap interface to the driver.
18And since xquake uses mmap, mmap is considered important :-)
19and no sane application uses ALaw/uLaw these days anyway.
20In short, playing a Sun .au file as follows:
21
22cat my_file.au > /dev/dsp
23
24does not work. Instead, you may use the play script from
25Chris Bagwell's sox-12.14 package (available from the URL
26below) to play many different audio file formats.
27The script automatically determines the audio format
28and does do audio conversions if necessary.
29http://home.sprynet.com/sprynet/cbagwell/projects.html
30
31
32Blocking vs. nonblocking IO
33---------------------------
34
35Unlike OSS/Free this driver honours the O_NONBLOCK file flag
36not only during open, but also during read and write.
37This is an effort to make the sound driver interface more
38regular. Timidity has problems with this; a patch
39is available from http://www.ife.ee.ethz.ch/~sailer/linux/pciaudio.html.
40(Timidity patched will also run on OSS/Free).
41
42
43MIDI UART
44---------
45
46The driver supports a simple MIDI UART interface, with
47no ioctl's supported.
48
49
50MIDI synthesizer
51----------------
52
53The card both has an OPL compatible FM synthesizer as well as
54a wavetable synthesizer.
55
56I haven't managed so far to get the OPL synth running.
57
58Using the wavetable synthesizer requires allocating
591-4MB of physically contiguous memory, which isn't possible
60currently on Linux without ugly hacks like the bigphysarea
61patch. Therefore, the driver doesn't support wavetable
62synthesis.
63
64
65No support from S3
66------------------
67
68I do not get any support from S3. Therefore, the driver
69still has many problems. For example, although the manual
70states that the chip should be able to access the sample
71buffer anywhere in 32bit address space, I haven't managed to
72get it working with buffers above 16M. Therefore, the card
73has the same disadvantages as ISA soundcards.
74
75Given that the card is also very noisy, and if you haven't
76already bought it, you should strongly opt for one of the
77comparatively priced Ensoniq products.
78
79
80Thomas Sailer
81t.sailer@alumni.ethz.ch