I cannot get any sound out from my raspi.
I have another SD with XBian and XBMC running so HW problem is discarted.
this is my lsmod
pi#cacharro ~ $ lsmod
Module Size Used by
snd_bcm2835 16165 0
snd_soc_bcm2708_i2s 5474 0
regmap_mmio 2806 1 snd_soc_bcm2708_i2s
snd_soc_core 131268 1 snd_soc_bcm2708_i2s
regmap_spi 1897 1 snd_soc_core
snd_pcm 81593 2 snd_bcm2835,snd_soc_core
snd_page_alloc 5156 1 snd_pcm
regmap_i2c 1645 1 snd_soc_core
snd_compress 8076 1 snd_soc_core
snd_seq 53769 0
snd_timer 20133 2 snd_pcm,snd_seq
evdev 9419 2
snd_seq_device 6473 1 snd_seq
leds_gpio 2059 0
led_class 3688 1 leds_gpio
snd 61291 7
snd_bcm2835,snd_soc_core,snd_timer,snd_pcm,snd_seq,snd_seq_device,snd_compress
I tried speaker-test -t sine -f 600 , nothing sounds.
I tried with HDMI, with headphones and with both at the same time. Nothing.
alsa-utils is installed
I want to play midi using ZynSubAddFX.
Any clue ?? Any extra details that may be useful ??
I finally bought a 1.34€ USB sound card, is not an ideal solution but I got quality audio and mic line for the same price :)
Related
I am trying to record 4 channels with arecord but the last two are all zeros. I have a Behringer UMC404HD which is a 4 channel audio ADC with a USB port. I'm connecting it to machines running different flavors of linux (CentOS, Raspian, ubuntu and Pop!_OS). Only the CentOS one works correctly, giving me 4 channels; the others all seem to accept 4 channels but the last two channels are all 0s.
On the PopOS machine I used
arecord -l
**** List of CAPTURE Hardware Devices ****
card 1: Generic [HD-Audio Generic], device 0: ALC293 Analog [ALC293 Analog]
Subdevices: 1/1
Subdevice #0: subdevice #0
card 2: U192k [UMC404HD 192k], device 0: USB Audio [USB Audio]
Subdevices: 1/1
Subdevice #0: subdevice #0
and got this
arecord --dump-hw-params -D plughw:2,0 -c 4 -r 96000 -t raw -f S32_LE | hexdump | more
Recording raw data 'stdin' : Signed 32 bit Little Endian, Rate 96000 Hz, Channels 4
HW Params of device "plughw:2,0":
--------------------
ACCESS: MMAP_INTERLEAVED MMAP_NONINTERLEAVED MMAP_COMPLEX RW_INTERLEAVED RW_NONINTERLEAVED
FORMAT: S8 U8 S16_LE S16_BE U16_LE U16_BE S24_LE S24_BE U24_LE U24_BE S32_LE S32_BE U32_LE U32_BE FLOAT_LE FLOAT_BE FLOAT64_LE FLOAT64_BE MU_LAW A_LAW IMA_ADPCM S20_LE S20_BE U20_LE U20_BE S24_3LE S24_3BE U24_3LE U24_3BE S20_3LE S20_3BE U20_3LE U20_3BE S18_3LE S18_3BE U18_3LE U18_3BE
SUBFORMAT: STD
SAMPLE_BITS: [4 64]
FRAME_BITS: [4 640000]
CHANNELS: [1 10000]
RATE: [4000 4294967295)
PERIOD_TIME: [125 743039)
PERIOD_SIZE: (0 3191328204)
PERIOD_BYTES: (0 4294967295)
PERIODS: (0 4294967295]
BUFFER_TIME: [1 4294967295]
BUFFER_SIZE: [1 4294967294]
BUFFER_BYTES: [1 4294967295]
TICK_TIME: ALL
--------------------
0000000 5600 0061 7900 1afb 0000 0000 0000 0000
0000010 1a00 0049 1c00 1b29 0000 0000 0000 0000
0000020 5300 004b e100 1b44 0000 0000 0000 0000
0000030 eb00 005b 5300 1b50 0000 0000 0000 0000
...
0000160 f300 fff5 f000 1071 0000 0000 0000 0000
I've tried both -D hw:2,0 and -D plughw:2,0 to no avail.
The CentOS works fine although the device is different:
arecord -l
output is
arecord --dump-hw-params -D plughw:1,0 -c 4 -r 96000 -t raw -f S32_LE | hexdump | more
Recording raw data 'stdin' : Signed 32 bit Little Endian, Rate 96000 Hz, Channels 4
HW Params of device "plughw:1,0":
--------------------
ACCESS: MMAP_INTERLEAVED MMAP_NONINTERLEAVED MMAP_COMPLEX RW_INTERLEAVED RW_NONINTERLEAVED
FORMAT: S8 U8 S16_LE S16_BE U16_LE U16_BE S24_LE S24_BE U24_LE U24_BE S32_LE S32_BE U32_LE U32_BE FLOAT_LE FLOAT_BE FLOAT64_LE FLOAT64_BE MU_LAW A_LAW IMA_ADPCM S20_LE S20_BE U20_LE U20_BE S24_3LE S24_3BE U24_3LE U24_3BE S20_3LE S20_3BE U20_3LE U20_3BE S18_3LE S18_3BE U18_3LE U18_3BE
SUBFORMAT: STD
SAMPLE_BITS: [4 64]
FRAME_BITS: [4 640000]
CHANNELS: [1 10000]
RATE: [4000 4294967295)
PERIOD_TIME: [125 743039)
PERIOD_SIZE: (0 3191328204)
PERIOD_BYTES: (0 4294967295)
PERIODS: (0 4294967295]
BUFFER_TIME: [1 4294967295]
BUFFER_SIZE: [1 4294967294]
BUFFER_BYTES: [1 4294967295]
TICK_TIME: ALL
--------------------
0000000 f800 005a eb00 1b39 6300 272a 2200 0274
0000010 bc00 0073 4500 1b4e 1400 2605 2900 0235
...
From what I can tell the only difference is the output: all zeros for the last two channels in the PopOS machine and content for the last two channels in the CentOS example. (The RPI and Ubuntu machine behaved the same as the PopOS device).
On a whim, I tried joining the audio group but it did not help.
Thoughts? any advice on what i can try to debug this further? Thanks!
Resolved! It turns out I needed to enable all the channels using AlsaMixer. The missing channels were enabled by using F4 for capture then selecting the channel and hitting the space bar.
You can have udev run a script to automatically enable capture on all inputs and set volume. https://gitlab.com/sbyrne/umc404hd-autocapture
I'm running uClinux on a SmartFusion2 as part of a University team building a small cube satellite. However, I'm not super experienced in Linux kernel, and this issue has had me stumped for a few days. I'm trying to get the SmartFusion to run a program on bootup. Currently, the only .uImage that does this is the test 'hello' file. I'm trying to recreate the process for another program, but am running into some difficulties.
in my hello directory I have the following files: hello.busybox, hello.kernel.M2S, help.txt, hello.uImage, Makefile, hello.initramfs, hello (directory)
in the hello subdirectory (projects/hello/hello):
hello (executable), hello.c, hello.gdb, hello.h, hello.o, Makefile
to try and get the uImage to boot and run a different program, I made a copy of my projects/hello/hello directory and renamed it 'goodbye', with a few minor changes int the .h and .c files for testing purposes. Now I'm trying to get the executable 'hello' in projects/hello/goodbye to run on boot.
My initramfs file originally looked like this:
# This is a very simple, default initramfs
dir /dev 0755 0 0
nod /dev/console 0600 0 0 c 5 1
nod /dev/tty 0666 0 0 c 5 0
nod /dev/null 0600 0 0 c 1 3
nod /dev/mem 0600 0 0 c 1 1
nod /dev/kmem 0600 0 0 c 1 2
nod /dev/zero 0600 0 0 c 1 5
nod /dev/random 0600 0 0 c 1 8
nod /dev/urandom 0600 0 0 c 1 9
dir /dev/pts 0755 0 0
nod /dev/ptmx 0666 0 0 c 5 2
nod /dev/ttyS0 0666 0 0 c 4 64
nod /dev/ttyS1 0666 0 0 c 4 65
nod /dev/ttyS2 0666 0 0 c 4 66
nod /dev/ttyS3 0666 0 0 c 4 67
nod /dev/ttyS4 0666 0 0 c 4 68
nod /dev/ttyS5 0666 0 0 c 4 69
dir /bin 755 0 0
dir /proc 755 0 0
file /bin/hello ${INSTALL_ROOT}/projects/${SAMPLE}/hello/hello 755 0 0
slink /bin/init hello 777 0 0
I changed the last two lines of the initramfs to read as follows:
file /bin/hello ${INSTALL_ROOT}/projects/${SAMPLE}/hello/goodbye 755 0 0
slink /bin/init hello 777 0 0
But when I try and boot the SmartFusion2 after remaking the uImage, I get this, witht the error at the bottom:
Starting kernel ...
Linux version 2.6.33-arm1 (ecenstudent#EE10308) (gcc version 4.4.1 (Sourcery G++ Lite 2010q1-189) ) #38 Thu May 25 09:09:08 MDT 2017
CPU: ARMv7-M Processor [412fc231] revision 1 (ARMv7M)
CPU: NO data cache, 8K instruction cache
Machine: Microsemi M2S
Built 1 zonelists in Zone order, mobility grouping on. Total pages: 16256
Kernel command line: m2s_platform=m2s-fg484-som console=ttyS0,115200 panic=10 ip=10.2.118.102:10.2.118.101:192.168.0.1::m2s-fg484-som:eth0:off ethaddr=3C:FB:96:05:00:53
PID hash table entries: 256 (order: -2, 1024 bytes)
Dentry cache hash table entries: 8192 (order: 3, 32768 bytes)
Inode-cache hash table entries: 4096 (order: 2, 16384 bytes)
Memory: 64MB = 64MB total
Memory: 64408k/64408k available, 1128k reserved, 0K highmem
Virtual kernel memory layout:
vector : 0x00000000 - 0x00001000 ( 4 kB)
fixmap : 0xfff00000 - 0xfffe0000 ( 896 kB)
vmalloc : 0x00000000 - 0xffffffff (4095 MB)
lowmem : 0xa0000000 - 0xa4000000 ( 64 MB)
modules : 0xa0000000 - 0x01000000 (1552 MB)
.init : 0xa0008000 - 0xa0012000 ( 40 kB)
.text : 0xa0074bc0 - 0xa0083000 ( 58 kB)
.data : 0xa0084000 - 0xa008cce0 ( 36 kB)
Hierarchical RCU implementation.
NR_IRQS:83
Calibrating delay loop... 132.30 BogoMIPS (lpj=661504)
Mount-cache hash table entries: 512
Switching to clocksource mss_timer2
Serial: 8250/16550 driver, 2 ports, IRQ sharing disabled
serial8250.0: ttyS0 at MMIO 0x40000000 (irq = 10) is a 16550A
console [ttyS0] enabled
serial8250.1: ttyS1 at MMIO 0x40010000 (irq = 11) is a 16550A
Freeing init memory: 40K
Kernel panic - not syncing: No init found. Try passing init= option to kernel.
Backtrace: no frame pointer
Rebooting in 10 seconds..
Can somebody help explain why this is happening and what I need to do to my initramfs to make it run the proper program on boot? Thanks!!
As it turns out, I was confused about how those two lines worked. When I finally figured it out, they looked like this:
file /bin/hello ${INSTALL_ROOT}/projects/${SAMPLE}/goodbye/hello 755 0 0
slink /bin/init hello 777 0 0
then it worked as desired, and I was able to implement it into other uImages.
I have a custom board based on am335x. I am building a buildroot for a minimal root filesystem (minimal by size) : boots off as initramfs. I am able to boot the image but unfortunately there are no /dev/mmcblk0 entry.
I would like to know how to make it create that entry.
The following is some log and data to help.
======================================================================
# ls /dev
console ram14 tty26 tty55
cpu_dma_latency ram15 tty27 tty56
full ram2 tty28 tty57
hwrng ram3 tty29 tty58
i2c-0 ram4 tty3 tty59
i2c-1 ram5 tty30 tty6
input ram6 tty31 tty60
kmem ram7 tty32 tty61
kmsg ram8 tty33 tty62
loop-control ram9 tty34 tty63
loop0 random tty35 tty7
loop1 shm tty36 tty8
loop2 tty tty37 tty9
loop3 tty0 tty38 ttyO0
loop4 tty1 tty39 ttyO1
loop5 tty10 tty4 ttyS0
loop6 tty11 tty40 ttyS1
loop7 tty12 tty41 ttyS2
mem tty13 tty42 ttyS3
network_latency tty14 tty43 ubi_ctrl
network_throughput tty15 tty44 urandom
null tty16 tty45 usbmon0
port tty17 tty46 vcs
psaux tty18 tty47 vcs1
ptmx tty19 tty48 vcsa
pts tty2 tty49 vcsa1
ram0 tty20 tty5 watchdog
ram1 tty21 tty50 watchdog0
ram10 tty22 tty51 zero
ram11 tty23 tty52
ram12 tty24 tty53
ram13 tty25 tty54
# cat /proc/partitions
major minor #blocks name# cat /proc/devices
Character devices:
1 mem
4 /dev/vc/0
4 tty
4 ttyS
5 /dev/tty
5 /dev/console
5 /dev/ptmx
7 vcs
10 misc
13 input
29 fb
89 i2c
90 mtd
128 ptm
136 pts
153 spi
166 ttyACM
180 usb
188 ttyUSB
189 usb_device
226 drm
248 ttySDIO
249 usbmon
250 ttyO
251 watchdog
252 ptp
253 pps
254 rtc
Block devices:
1 ramdisk
259 blkext
7 loop
8 sd
31 mtdblock
65 sd
66 sd
67 sd
68 sd
69 sd
70 sd
71 sd
128 sd
129 sd
130 sd
131 sd
132 sd
133 sd
134 sd
135 sd
179 mmc
# cat /etc/fstab
# <file system> <mount pt> <type> <options> <dump> <pass>
/dev/root / ext2 rw,noauto 0 1
proc /proc proc defaults 0 0
devpts /dev/pts devpts defaults,gid=5,mode=620 0 0
tmpfs /dev/shm tmpfs mode=0777 0 0
tmpfs /tmp tmpfs mode=1777 0 0
tmpfs /run tmpfs mode=0755,nosuid,nodev 0 0
sysfs /sys sysfs defaults 0 0
==================================================================
It is booting busybox and using devtmpfs which are defaults for buildroot.
If I use TI's minimalfs, it does show /dev/mmcblk0 so the kernel and device tree are ok. How to solve this.
Regards,
Preetam
You can create this node manually by mknod
mknod [OPTION]... NAME TYPE [MAJOR MINOR]
In your case type would be b (block). Major number you may find in sources or use
cat /proc/devices the minor number is a partition number.
If this is not the case, try to enable udev in buildroot config.
in the linux, lsmod lists a lot of modules. but how can we find where those module loaded from.
for some modules,linux command "modprobe -l" shows a path but some are not.
edited
i also tried "find" and "locate". both of them lists all kind of versions
locate fake
/svf/SVDrv/kernel/linux/.fake.ko.cmd
/svf/SVDrv/kernel/linux/.fake.mod.o.cmd
/svf/SVDrv/kernel/linux/.fake.o.cmd
/svf/SVDrv/kernel/linux/fake.ko
/svf/SVDrv/kernel/linux/fake.mod.o
/svf/SVDrv/kernel/linux/fake.o
/svf/SVDrv.03.11.2014.16.00/kernel/linux/.fake.ko.cmd
/svf/SVDrv.03.11.2014.16.00/kernel/linux/.fake.mod.o.cmd
/svf/SVDrv.03.11.2014.16.00/kernel/linux/.fake.o.cmd
/svf/SVDrv.03.11.2014.16.00/kernel/linux/fake.ko
/svf/SVDrv.03.11.2014.16.00/kernel/linux/fake.mod.o
/svf/SVDrv.03.11.2014.16.00/kernel/linux/fake.o
/svf/SVDrv.04.29.2014.17.39/kernel/linux/.fake.ko.cmd
/svf/SVDrv.04.29.2014.17.39/kernel/linux/.fake.mod.o.cmd
/svf/SVDrv.04.29.2014.17.39/kernel/linux/.fake.o.cmd
/svf/SVDrv.04.29.2014.17.39/kernel/linux/fake.ko
/svf/SVDrv.04.29.2014.17.39/kernel/linux/fake.mod.o
/svf/SVDrv.04.29.2014.17.39/kernel/linux/fake.o
/svf/SVDrv.05.05.2014.11.25/kernel/linux/.fake.ko.cmd
/svf/SVDrv.05.05.2014.11.25/kernel/linux/.fake.mod.o.cmd
/svf/SVDrv.05.05.2014.11.25/kernel/linux/.fake.o.cmd
/svf/SVDrv.05.05.2014.11.25/kernel/linux/fake.ko
/svf/SVDrv.05.05.2014.11.25/kernel/linux/fake.mod.o
/svf/SVDrv.05.05.2014.11.25/kernel/linux/fake.o
/svf/SVDrv.05.05.2014.17.43/kernel/linux/.fake.ko.cmd
/svf/SVDrv.05.05.2014.17.43/kernel/linux/.fake.mod.o.cmd
/svf/SVDrv.05.05.2014.17.43/kernel/linux/.fake.o.cmd
/svf/SVDrv.05.05.2014.17.43/kernel/linux/fake.ko
/svf/SVDrv.05.05.2014.17.43/kernel/linux/fake.mod.o
/svf/SVDrv.05.05.2014.17.43/kernel/linux/fake.o
/svf/SVDrv.05.07.2014.14.59/kernel/linux/.fake.ko.cmd
/svf/SVDrv.05.07.2014.14.59/kernel/linux/.fake.mod.o.cmd
/svf/SVDrv.05.07.2014.14.59/kernel/linux/.fake.o.cmd
/svf/SVDrv.05.07.2014.14.59/kernel/linux/fake.ko
/svf/SVDrv.05.07.2014.14.59/kernel/linux/fake.mod.o
/svf/SVDrv.05.07.2014.14.59/kernel/linux/fake.o
Sorry if the answer comes a bit late but I just stumbled across this particular question myself today...
To minimize manual labor here is my listing of the paths curretly loaded modules are loaded from:
awk '{ print $1 }' /proc/modules | xargs modinfo -n | sort
I needed this to create a minimal kernel image containg only the modules i really need.
Unfortunately lsmod only displays the name field which does not alwys match the modules# file name (e.g phy-am335x-control.ko and phy_am335x_control).
I hope this helps.
You can use "locate" or "find" command on these modules to find where they are , for example
[root#localhost core_src]# lsmod
Module Size Used by
iptable_filter 2793 0
ipt_MASQUERADE 2466 1
iptable_nat 6158 1
vmware_balloon 7199 0
i2c_piix4 12608 0
i2c_core 31276 1 i2c_piix4
shpchp 33482 0
ext4 371331 2
mbcache 8144 1 ext4
jbd2 93312 1 ext4
sd_mod 39488 4
crc_t10dif 1541 1 sd_mod
sr_mod 16228 0
cdrom 39803 1 sr_mod
mptspi 17051 3
mptscsih 36828 1 mptspi
mptbase 94005 2 mptspi,mptscsih
scsi_transport_spi 26151 1 mptspi
pata_acpi 3701 0
ata_generic 3837 0
ata_piix 22846 0
dm_mirror 14101 0
dm_region_hash 12170 1 dm_mirror
dm_log 10122 2 dm_mirror,dm_region_hash
dm_mod 81692 2 dm_mirror,dm_log
[root#localhost core_src]# locate vmware_balloon
/lib/modules/2.6.32-279.el6.x86_64/kernel/drivers/misc/vmware_balloon.ko
Get the paths from the list of loaded modules. Without the need for awk.
while IFS= read -r line;
do modinfo -n "${line%% *}"
done < /proc/modules | sort
I've decided to bring up a GSM Modem for my Linux machine (OpenSuse 12.1 64-bit on Vmware) so that I can use it as the SMS gateway. I've got a Wavecom M1306B GSM modem which provides a USB interface, and obviously there is a USB cable (end to end, GSM Modem to my Desktop) with it.
I tested this modem successfully with my Windows 7 64-bit PC by running some basic commands on it. (like: AT , ATZ, ..)
Here are some of my logs:
machine2:~ # lsusb
Bus 001 Device 001: ID 1d6b:0001 Linux Foundation 1.1 root hub
Bus 001 Device 002: ID 0e0f:0003 VMware, Inc. Virtual Mouse
Bus 001 Device 003: ID 0e0f:0002 VMware, Inc. Virtual USB Hub
Bus 001 Device 006: ID 067b:2303 Prolific Technology, Inc. PL2303 Serial Port
lsusb -v output for that interface:
Bus 001 Device 006: ID 067b:2303 Prolific Technology, Inc. PL2303 Serial Port
Device Descriptor:
bLength 18
bDescriptorType 1
bcdUSB 1.10
bDeviceClass 0 (Defined at Interface level)
bDeviceSubClass 0
bDeviceProtocol 0
bMaxPacketSize0 64
idVendor 0x067b Prolific Technology, Inc.
idProduct 0x2303 PL2303 Serial Port
bcdDevice 3.00
iManufacturer 1 Prolific Technology Inc.
iProduct 2 USB-Serial Controller
iSerial 0
bNumConfigurations 1
Configuration Descriptor:
bLength 9
bDescriptorType 2
wTotalLength 39
bNumInterfaces 1
bConfigurationValue 1
iConfiguration 0
bmAttributes 0xa0
(Bus Powered)
Remote Wakeup
MaxPower 100mA
Interface Descriptor:
bLength 9
bDescriptorType 4
bInterfaceNumber 0
bAlternateSetting 0
bNumEndpoints 3
bInterfaceClass 255 Vendor Specific Class
bInterfaceSubClass 0
bInterfaceProtocol 0
iInterface 0
Endpoint Descriptor:
bLength 7
bDescriptorType 5
bEndpointAddress 0x81 EP 1 IN
bmAttributes 3
Transfer Type Interrupt
Synch Type None
Usage Type Data
wMaxPacketSize 0x000a 1x 10 bytes
bInterval 1
Endpoint Descriptor:
bLength 7
bDescriptorType 5
bEndpointAddress 0x02 EP 2 OUT
bmAttributes 2
Transfer Type Bulk
Synch Type None
Usage Type Data
wMaxPacketSize 0x0040 1x 64 bytes
bInterval 0
Endpoint Descriptor:
bLength 7
bDescriptorType 5
bEndpointAddress 0x83 EP 3 IN
bmAttributes 2
Transfer Type Bulk
Synch Type None
Usage Type Data
wMaxPacketSize 0x0040 1x 64 bytes
bInterval 0
Device Status: 0x0000
(Bus Powered)
machine2:/proc # setserial -a /dev/ttyUSB0
/dev/ttyUSB0, Line 0, UART: 16654, Port: 0x0000, IRQ: 0
Baud_base: 460800, close_delay: 0, divisor: 0
closing_wait: infinte
Flags: spd_normal
machine2:/home/smsto/bin # setserial -a /dev/ttyS0
/dev/ttyS0, Line 0, UART: 16550A, Port: 0x03f8, IRQ: 4
Baud_base: 115200, close_delay: 50, divisor: 0
closing_wait: 3000
Flags: spd_normal skip_test
machine2:/home/smsto/bin # setserial -a /dev/ttyS1
/dev/ttyS1, Line 1, UART: 16550A, Port: 0x02f8, IRQ: 3
Baud_base: 115200, close_delay: 50, divisor: 0
closing_wait: 3000
Flags: spd_normal skip_test
machine2:/proc # setserial -G /dev/ttyUSB0
/dev/ttyUSB0 uart 16654 port 0x0000 irq 0 baud_base 460800 spd_normal
machine2:/proc # setserial /dev/ttyUSB0
/dev/ttyUSB0, UART: 16654, Port: 0x0000, IRQ: 0
machine2:/proc/tty/driver # ls -ltr
total 0
-r--r--r-- 1 root root 0 Jan 10 14:03 usbserial
-r--r--r-- 1 root root 0 Jan 10 14:03 serial
machine2:/proc/tty/driver # cat serial
serinfo:1.0 driver revision:
0: uart:16550A port:000003F8 irq:4 tx:0 rx:0 CTS|DSR|CD
1: uart:16550A port:000002F8 irq:3 tx:0 rx:0 CTS|DSR|CD
2: uart:unknown port:000003E8 irq:4
3: uart:unknown port:000002E8 irq:3
4: uart:unknown port:00000000 irq:0
5: uart:unknown port:00000000 irq:0
6: uart:unknown port:00000000 irq:0
7: uart:unknown port:00000000 irq:0
machine2:/proc/tty/driver # cat usbserial
usbserinfo:1.0 driver:2.0
0: module:pl2303 name:"pl2303" vendor:067b product:2303 num_ports:1 port:1 path:usb-0000:02:00.0-2.1
machine2:/proc/tty # cat drivers
/dev/tty /dev/tty 5 0 system:/dev/tty
/dev/console /dev/console 5 1 system:console
/dev/ptmx /dev/ptmx 5 2 system
/dev/vc/0 /dev/vc/0 4 0 system:vtmaster
usbserial /dev/ttyUSB 188 0-253 serial
serial /dev/ttyS 4 64-79 serial
pty_slave /dev/pts 136 0-1048575 pty:slave
pty_master /dev/ptm 128 0-1048575 pty:master
unknown /dev/tty 4 1-63 console
machine2:/proc/tty # dmesg | grep -i tty
[ 1.383652] serial8250: ttyS0 at I/O 0x3f8 (irq = 4) is a 16550A
[ 1.424541] serial8250: ttyS1 at I/O 0x2f8 (irq = 3) is a 16550A
[ 1.581063] 00:0a: ttyS0 at I/O 0x3f8 (irq = 4) is a 16550A
[ 1.654207] 00:0b: ttyS1 at I/O 0x2f8 (irq = 3) is a 16550A
[ 1.938507] tty tty17: hash matches
[ 2498.137304] usb 1-2.1: pl2303 converter now attached to ttyUSB0
I noticed that the Baud rate of USB0 interface is too much, so i tried to assign 115200 :
machine2:/proc # setserial /dev/ttyUSB0 baud_base 115200
Cannot set serial info: Invalid argument
So, it is the problem ... and I receive this error.
Whenever I try to connect S0, S1, USB0 interfaces via minicom, it simply doesn't work.
Baud_base is not the port speed, it's the maximum speed when a frequency divisor is 1. The ability to set baud_base probably doesn't apply to USB serial device at all, and it's most certainly not what you want.
Use stty to set the port speed, or use cu or minicom for testing (they can set port speed by themselves).
I'm not sure about the baud rate but If you open up another terminal and do cat /dev/ttyUSB0
Then in the first terminal do echo AT > /dev/ttyUSB0 you might get an OK back..not sure if it helps but it should get you a response at least..