[OMAP3530] OMAP:DSS: LCD display blanks out after about 10 minutes

Ken,

I don't know much about the different releases, but I do know I used to have to disable the frame buffer timeout using the following sysfs entry...

echo 0 > /sys/power/fb_timeout_value

Not sure if this exists in the latest releases or not though.

BR,

Steve

Steve,

I've been looking for something like that but here is what I find on my target system:

/: cd /
/: find / -name *timeout*
/proc/sys/kernel/hung_task_timeout_secs
/proc/sys/fs/nfs/idmap_cache_timeout
/proc/sys/fs/nfs/nfs_mountpoint_timeout
/proc/sys/fs/nfs/nlm_timeout
/proc/sys/net/ipv4/route/gc_timeout
/proc/sys/net/ipv4/tcp_fin_timeout
/proc/sys/sunrpc/tcp_fin_timeout
/sys/module/nfs/parameters/cache_getent_timeout
/sys/module/nfs/parameters/idmap_cache_timeout
/sys/module/lockd/parameters/nlm_timeout
/sys/module/keyboard/parameters/brl_timeout
/: find / -name fb*
/dev/fb2
/dev/fb1
/dev/fb0
/home/root/fbgrab
/proc/fb
/sys/devices/platform/omapfb/graphics/fb0
/sys/devices/platform/omapfb/graphics/fb1
/sys/devices/platform/omapfb/graphics/fb2
/sys/devices/virtual/graphics/fbcon
/sys/class/graphics/fbcon
/sys/class/graphics/fb0
/sys/class/graphics/fb1
/sys/class/graphics/fb2
/usr/sbin/fbset
/: ls -l /proc/fb
-r--r--r--    1 root     root            0 Jan 21 14:33 /proc/fb
/: ls -l /dev/fb0
crw-rw----    1 root     root      29,   0 Jan 19 14:56 /dev/fb0
/: find / -name *time*
/dev/timer
/etc/localtime
/proc/asound/timers
/proc/uptime
/proc/timer_list
/proc/sys/kernel/sched_rt_runtime_us
/proc/sys/kernel/hung_task_timeout_secs
/proc/sys/fs/lease-break-time
/proc/sys/fs/nfs/idmap_cache_timeout
/proc/sys/fs/nfs/nfs_mountpoint_timeout
/proc/sys/fs/nfs/nlm_timeout
/proc/sys/net/core/xfrm_aevent_etime
/proc/sys/net/ipv4/route/gc_timeout
/proc/sys/net/ipv4/neigh/default/retrans_time
/proc/sys/net/ipv4/neigh/default/base_reachable_time
/proc/sys/net/ipv4/neigh/default/delay_first_probe_time
/proc/sys/net/ipv4/neigh/default/gc_stale_time
/proc/sys/net/ipv4/neigh/default/locktime
/proc/sys/net/ipv4/neigh/default/retrans_time_ms
/proc/sys/net/ipv4/neigh/default/base_reachable_time_ms
/proc/sys/net/ipv4/neigh/lo/retrans_time
/proc/sys/net/ipv4/neigh/lo/base_reachable_time
/proc/sys/net/ipv4/neigh/lo/delay_first_probe_time
/proc/sys/net/ipv4/neigh/lo/gc_stale_time
/proc/sys/net/ipv4/neigh/lo/locktime
/proc/sys/net/ipv4/neigh/lo/retrans_time_ms
/proc/sys/net/ipv4/neigh/lo/base_reachable_time_ms
/proc/sys/net/ipv4/neigh/eth0/retrans_time
/proc/sys/net/ipv4/neigh/eth0/base_reachable_time
/proc/sys/net/ipv4/neigh/eth0/delay_first_probe_time
/proc/sys/net/ipv4/neigh/eth0/gc_stale_time
/proc/sys/net/ipv4/neigh/eth0/locktime
/proc/sys/net/ipv4/neigh/eth0/retrans_time_ms
/proc/sys/net/ipv4/neigh/eth0/base_reachable_time_ms
/proc/sys/net/ipv4/tcp_timestamps
/proc/sys/net/ipv4/tcp_keepalive_time
/proc/sys/net/ipv4/tcp_fin_timeout
/proc/sys/net/ipv4/inet_peer_gc_mintime
/proc/sys/net/ipv4/inet_peer_gc_maxtime
/proc/sys/net/ipv4/ipfrag_time
/proc/sys/sunrpc/tcp_fin_timeout
/sbin/adjtimex
/sys/devices/platform/i2c_omap.1/i2c-1/1-0068/rtc/rtc0/time
/sys/devices/system/timer
/sys/devices/system/timer/timer0
/sys/devices/system/timekeeping
/sys/devices/system/timekeeping/timekeeping0
/sys/devices/virtual/sound/timer
/sys/class/sound/timer
/sys/module/printk/parameters/time
/sys/module/nfs/parameters/cache_getent_timeout
/sys/module/nfs/parameters/idmap_cache_timeout
/sys/module/lockd/parameters/nlm_timeout
/sys/module/keyboard/parameters/brl_timeout
/sys/module/snd_timer
/sys/module/snd_timer/parameters/timer_tstamp_monotonic
/sys/module/snd_timer/parameters/timer_limit
/usr/bin/time
/usr/bin/uptime

/: ls -l /sys/devices/platform/omapfb/graphics/fb0
-rw-r--r--    1 root     root         4096 Jan 19 14:56 bits_per_pixel
-rw-r--r--    1 root     root         4096 Jan 19 14:56 blank
-rw-r--r--    1 root     root         4096 Jan 19 14:56 console
-rw-r--r--    1 root     root         4096 Jan 19 14:56 cursor
-r--r--r--    1 root     root         4096 Jan 19 14:56 dev
lrwxrwxrwx    1 root     root            0 Jan 19 14:56 device -> ../../../omapfb
-rw-r--r--    1 root     root         4096 Jan 19 14:56 mirror
-rw-r--r--    1 root     root         4096 Jan 19 14:56 mode
-rw-r--r--    1 root     root         4096 Jan 19 14:56 modes
-r--r--r--    1 root     root         4096 Jan 19 14:56 name
-rw-r--r--    1 root     root         4096 Jan 19 14:56 overlays
-rw-r--r--    1 root     root         4096 Jan 19 14:56 overlays_rotate
-rw-r--r--    1 root     root         4096 Jan 19 14:56 pan
-r--r--r--    1 root     root         4096 Jan 19 14:56 phys_addr
-rw-r--r--    1 root     root         4096 Jan 19 14:56 rotate
-rw-r--r--    1 root     root         4096 Jan 19 14:56 rotate_type
-rw-r--r--    1 root     root         4096 Jan 19 14:56 size
-rw-r--r--    1 root     root         4096 Jan 19 14:56 state
-r--r--r--    1 root     root         4096 Jan 19 14:56 stride
lrwxrwxrwx    1 root     root            0 Jan 19 14:56 subsystem -> ../../../../../class/graphics
-rw-r--r--    1 root     root         4096 Jan 19 14:56 uevent
-r--r--r--    1 root     root         4096 Jan 19 14:56 virt_addr
-rw-r--r--    1 root     root         4096 Jan 19 14:56 virtual_size

/: ls -l /sys/devices/virtual/graphics/fbcon
-rw-r--r--    1 root     root         4096 Jan 19 14:56 cursor_blink
-rw-r--r--    1 root     root         4096 Jan 19 14:56 rotate
--w-------    1 root     root         4096 Jan 19 14:56 rotate_all
lrwxrwxrwx    1 root     root            0 Jan 19 14:56 subsystem -> ../../../../class/graphics
-rw-r--r--    1 root     root         4096 Jan 19 14:56 uevent

/: ls -l /sys/class/graphics/fb0
lrwxrwxrwx    1 root     root            0 Jan 19 14:56 /sys/class/graphics/fb0 -> ../../devices/platform
/omapfb/graphics/fb0

If one of these is what I'm looking for please let me know.

Thanks,

Ken

As a clarification it appears that the PIXEL clock to lcd is what stops.

Hi Ken,

This is nothing to do with Power management as such, actually you have enabled Fbdev Console config option which is hooked up with TTY console, and this times out after 10 mins. This is Linux kernel TTY console behaviour, you can recover from this by doing

- Issue "echo 0 > /sys/class/graphics/fb0/blank" command to enable fbdev console again.

- Increase the TTY timeout value, go to the file drivers/char/vt.c and search for "blankinterval", which is configured to 10x60. This is module parameter you can overwrite this through boot argument also. There are other interfaces also (like SYSFS, IOCTL), which I am not aware of as of now.

- Disable Fbdev console all together

Thanks,

Vaibhav

Vaibhav,

Thank you for getting back on this.  I ended up just ignoring the blank request for the NORMAL case for my machine.  I didn't want to go through the effort of compiling and adding setterm to my file system just to stop the blanking.  I also played around a little with using echo but that was a bit peculiar.  I will most likely just pass a command line option in the future but for now I have it working so all is good.

Ken

Hi,

Try using "consoleblank=0" kernel parameter.

L.

Kalaiselvan Rajagopal said:

OK, setting the "blankinterval" to 0 serves the purpose.

It worked for me too !!! :)

You can also disable config option "CONFIG_FRAMEBUFFER_CONSOLE" in your config file. Also, note that, this will only make sure that, your display console will not get impacted due to console timeout.

Thanks,

Vaibhav