Serial port stops working after suspend
Bug #105380 reported by
Dima Ryazanov
Affects | Status | Importance | Assigned to | Milestone | |
---|---|---|---|---|---|
linux (Ubuntu) |
Won't Fix
|
Undecided
|
Andy Whitcroft |
Bug Description
Binary package hint: linux-image-
When my laptop wakes up after suspend, the serial port doesn't seem to work anymore. Programs can read from and write to it as before, but the data doesn't seem to be actually transmitted.
I don't know of any way to check the status of the serial port. After searching Google, I saw other people mention that the serial port uses IRQ 4, and its entry disappears from /proc/interrupts. But in my case, it doesn't appear there in the first place.
Also, the serial port driver is built into the kernel, and not compiled as a module. So I can't even try removing it and loading it again.
I'm using a Thinkpad T20, with ACPI enabled.
Changed in linux: | |
status: | Incomplete → Confirmed |
To post a comment you must log in.
I can confirm partly - for me the serial /dev/ttyS0 is used for the wacom pen (Thinkpad X60 tablet). After resume from RAM the pen does not work and "serial" has dissappeared from /proc/interrupts. I tried creating a /etc/acpi/ resume. d/20-setserial. sh containing s setserial command as suggested by ThinkWiki but that does not help.
The setserial command reports:
/dev/ttyS0, Line 0, UART: undefined, Port: 0x0200, IRQ: 5
closing_ wait: 3000
Baud_base: 921600, close_delay: 50, divisor: 0
Flags: spd_normal skip_test
and stty gives:
speed 19200 baud; rows 0; columns 0; line = 0;
intr = ^C; quit = ^\; erase = ^?; kill = ^U; eof = ^D; eol = <undef>;
eol2 = <undef>; swtch = <undef>; start = ^Q; stop = ^S; susp = ^Z; rprnt = ^R;
werase = ^W; lnext = ^V; flush = ^O; min = 1; time = 10;
-parenb -parodd cs8 hupcl -cstopb cread clocal -crtscts
-ignbrk -brkint -ignpar -parmrk -inpck -istrip -inlcr -igncr -icrnl -ixon ixoff
-iuclc -ixany -imaxbel -iutf8
-opost -olcuc -ocrnl onlcr -onocr -onlret -ofill -ofdel nl0 cr0 tab0 bs0 vt0 ff0
-isig -icanon -iexten -echo echoe echok -echonl -noflsh -xcase -tostop -echoprt
echoctl echoke
Wacom survives suspend to disk & resume.
I'm currently using linux-image- 2.6.20- 15-generic version 2.6.20-15.27.