staging-imx53: warning messages when device suspends, inconsistent suspend behavior

[Abhishek Paliwal]

Description:
==========
On iMX53 staging - https://android-build.linaro.org/builds/~linaro-android/staging-imx53/#build=135
Suspend is pretty inconsistent.
after bootup device is mostly in suspend mode, pressing power "hard" key on device brings it out of suspend mode but then USB keyboard and Mouse are not detected(connected after device bootup).

for every suspend mode warning messages shown on serial console:
----------
[ 252.529364] ------------[ cut here ]------------
[ 252.535749] WARNING: at arch/arm/plat-mxc/clock.c:57 __clk_disable+0x3c/0x80()
[ 252.537512] Modules linked in: gator
[ 252.545460] [<c0014960>] (unwind_backtrace+0x0/0xec) from [<c059bb1c>] (dump_stack+0x20/0x24)
[ 252.553186] [<c059bb1c>] (dump_stack+0x20/0x24) from [<c0031ea4>] (warn_slowpath_common+0x5c/0x74)
[ 252.561602] [<c0031ea4>] (warn_slowpath_common+0x5c/0x74) from [<c0031ee8>] (warn_slowpath_null+0x2c/0x34)
[ 252.569485] [<c0031ee8>] (warn_slowpath_null+0x2c/0x34) from [<c0021f20>] (__clk_disable+0x3c/0x80)
[ 252.576588] [<c0021f20>] (__clk_disable+0x3c/0x80) from [<c0021f9c>] (clk_disable+0x38/0x48)
[ 252.584496] [<c0021f9c>] (clk_disable+0x38/0x48) from [<c049b1a0>] (mxc_spdif_soc_suspend+0x34/0x4c)
[ 252.592742] [<c049b1a0>] (mxc_spdif_soc_suspend+0x34/0x4c) from [<c0491570>] (snd_soc_suspend+0x2c8/0x364)
[ 252.601076] [<c0491570>] (snd_soc_suspend+0x2c8/0x364) from [<c034b344>] (platform_pm_suspend+0x3c/0x6c)
[ 252.608364] [<c034b344>] (platform_pm_suspend+0x3c/0x6c) from [<c034f4c4>] (pm_op+0x60/0xbc)
[ 252.615467] [<c034f4c4>] (pm_op+0x60/0xbc) from [<c034f72c>] (__device_suspend+0x194/0x260)
[ 252.623193] [<c034f72c>] (__device_suspend+0x194/0x260) from [<c0350530>] (dpm_suspend+0xb8/0x1b0)
[ 252.630907] [<c0350530>] (dpm_suspend+0xb8/0x1b0) from [<c0350848>] (dpm_suspend_start+0x2c/0x30)
[ 252.639837] [<c0350848>] (dpm_suspend_start+0x2c/0x30) from [<c0073ce0>] (suspend_devices_and_enter+0xe4/0x368)
[ 252.648501] [<c0073ce0>] (suspend_devices_and_enter+0xe4/0x368) from [<c0074034>] (enter_state+0xd0/0x138)
[ 252.655638] [<c0074034>] (enter_state+0xd0/0x138) from [<c00740c0>] (pm_suspend+0x24/0x30)
[ 252.662277] [<c00740c0>] (pm_suspend+0x24/0x30) from [<c007506c>] (suspend+0x78/0x190)
[ 252.669566] [<c007506c>] (suspend+0x78/0x190) from [<c004d588>] (process_one_work+0x2fc/0x558)
[ 252.677638] [<c004d588>] (process_one_work+0x2fc/0x558) from [<c004e2bc>] (worker_thread+0x1d0/0x2d8)
[ 252.684741] [<c004e2bc>] (worker_thread+0x1d0/0x2d8) from [<c0052458>] (kthread+0xa4/0xb0)
[ 252.691646] [<c0052458>] (kthread+0xa4/0xb0) from [<c000e950>] (kernel_thread_exit+0x0/0x8)
[ 252.695381] ---[ end trace 10ec39fdd44bae9d ]---
----------

Unable to use device consistently.

Reproducible:
===========
Yes, 5/5 time

IMPACT:
========
Unable to use board smoothly. pretty inconsitent behavior in terms of suspend resume

Steps:
==========
1. Flash https://android-build.linaro.org/builds/~linaro-android/staging-imx53/#build=135
2. After device boots up insert USB keyboard and mouse
3. If device suspends - then resume by pressing "Power" hard key on device to resume.(as usb keyboard/mouse interrupts are not detected) - suspend-resume -

Issue:
1. happens every 15/20 seconds. Suspend happening frequently randomly.
2. warning messages on suspend. USB mouse /keyboard not detected.

Hardware:
==========
8GB class 10 transcend SD card
iMX53 quickstart
VGA out to monitor.
USB Mouse/Keyboard connected after device bootup

Software:
==========
https://android-build.linaro.org/builds/~linaro-android/staging-imx53/#build=135

Logs:
=========
Serial logs attached.

[Milosz Wasilewski (mwasilew)]

iMX53 is no longer supported.