[PATCH 0/9] various mainly pcf50633 resume improvements / Ooooh

[Sean McNeil]

Andy Green wrote:
> Somebody in the thread at some point said:
>
> |> Despite we made some real progress in fact the whole suspend / resume
> |> thing remains extremely fragile due to probably just one or two more
> |> monsters in the deep shadows we never understood yet.  And they're the
> |> kind of monsters that attack if you go hunting for them:
> |> no_console_suspend on the kernel commandline kills resume the same way
> |> as mdelay() in glamo suspend stuff, and equally with no real trace of
> |> how or why it blew chunks.
>
> | It works for a few times, then seems to crash. If I comment out the
> | dev_info ()and msleep() calls in pcf50633_work it seems to be OK. Also,
>
> OK I think I just had a "major breakthrough in understanding" why
> suspend action can be time-critical :-)
>
> We turn off our CPU core voltage quite early during suspend :-)))
> basically after pcf50633 suspends we are "running on fumes" for core_1v3
> in 23.3uF of capacitance for the rest of the suspend action. :-)))   So
> this is why the odd dev_info() (which has to be flushed on serial
> console) and msleep() can make a difference to if you are gonna resume.
>
> I'm going to meditate on this a bit, it is a serious issue because
> pcf50633 being an i2c peripheral from Linux's POV, it is suspended very
> early, and the i2c bus goes down a little while after so deferral is not
> really possible (unless we bitbang it ourselves I suppose).  But surely
> sawing off the branch you are sitting on by turning off your CPU core
> voltage is something your should preferably be doing at the END of
> suspend action not the start :-)
>
>
> Also I went back to look at why I could never make any change to the
> white flash that happens on suspend, I stuck mdelay(1000) in various
> places up the chain of suspends starting from Glamo going backwards,
> until I was able to delay the flash coming, which was when the delay was
> in pcf50633 suspend.  Further examination showed it was when we take the
> regulators down in preparation for suspend.
>
> I checked mach_gta02.c and I had told it to leave the lcm regulator up,
> but I could see it was taking it down.  When I told it to leave them all
> up, it still took lcm and some others down.  After some head scratching
> I saw that it meddles with that platform struct at runtime elsewhere in
> the file, so I forced it up there too.  Now there is no white flash (and
> I believe this will solve the monochrome LCM issue, since the power was
> getting taken until now).
>
> So that's up on andy branch now.
>
> | I still have it resuming as greyscale and the audio pops are still
> present.
>
> Greyscale I think will be fixed now.
>
> Audio pops... can you clarify where they come from... the earpiece or
> the sounder at the back / side.
This is so much better. Screen is now resuming in color. Resume is much 
more reliable as well. Yet even more reliable when I take out the 
dev_info() call in the _irq routine. I still get a complete lockup 
eventually, though. Seems like the longer I leave it in suspend the less 
likely it will resume.

The pops must be coming from the speaker on the side. I heard them even 
with the top off so the earpiece isn't even connected, right? They only 
happen on resume.

At the time of the suspend/resume I have audio opened as a pseudo alsa 
device which configures with the same info as stereoout.state. Here is 
the actual states:

	{ name 'PCM Volume'				value [ 235 235 ]			}
	{ name 'ADC Capture Volume'			value [ 195 195 ]			}
	{ name 'Headphone Playback Volume'		value [ 127 127 ]			}
	{ name 'Speaker Playback Volume'		value [ 0 0 ]				}
	{ name 'Mono Playback Volume'			value 121					}
	{ name 'Bypass Playback Volume'			value [ 2 2 ]				}
	{ name 'Sidetone Playback Volume'		value [ 2 2 ]				}
	{ name 'Voice Playback Volume'			value [ 2 2 ]				}
	{ name 'Headphone Playback ZC Switch'		value [ false false ]		}
	{ name 'Speaker Playback ZC Switch'		value [ false false ]		}
	{ name 'Mono Bypass Playback Volume'		value 2						}
	{ name 'Mono Sidetone Playback Volume'		value 2						}
	{ name 'Mono Voice Playback Volume'		value 2						}
	{ name 'Mono Playback ZC Switch'		value false					}
	{ name 'Bass Boost'				value 'Linear Control'		}
	{ name 'Bass Filter'				value '130Hz @ 48kHz'		}
	{ name 'Bass Volume'				value 0						}
	{ name 'Treble Volume'				value 0						}
	{ name 'Treble Cut-off'				value '8kHz'				}
	{ name 'Sidetone Capture Volume'		value [ 2 2 ]				}
	{ name 'Voice Sidetone Capture Volume'		value 2						}
	{ name 'Capture Volume'				value [ 23 23 ]				}
	{ name 'Capture ZC Switch'			value [ false false ]		}
	{ name 'Capture Switch'				value [ false false ]		}
	{ name 'Capture Filter Select'			value '3.4Hz @ 48kHz'		}
	{ name 'Capture Filter Cut-off'			value HiFi					}
	{ name 'Capture Filter Switch'			value true					}
	{ name 'ALC Capture Target Volume'		value 3						}
	{ name 'ALC Capture Max Volume'			value 7						}
	{ name 'ALC Capture Function'			value Off					}
	{ name 'ALC Capture ZC Switch'			value false					}
	{ name 'ALC Capture Hold Time'			value 15					}
	{ name 'ALC Capture Decay Time'			value 12					}
	{ name 'ALC Capture Attack Time'		value 2						}
	{ name 'ALC Capture NG Threshold'		value 0						}
	{ name 'ALC Capture NG Type'			value 'Constant PGA Gain'	}
	{ name 'ALC Capture NG Switch'			value false					}
	{ name '3D Function'				value Capture				}
	{ name '3D Upper Cut-off'			value '2.2kHz'				}
	{ name '3D Lower Cut-off'			value '200Hz'				}
	{ name '3D Volume'				value 0						}
	{ name '3D Switch'				value false					}
	{ name 'Capture 6dB Attenuate'			value false					}
	{ name 'Playback 6dB Attenuate'			value false					}
	{ name De-emphasis				value None					}
	{ name 'Playback Mono Mix'			value Stereo				}
	{ name 'Playback Phase'				value 'Non Inverted'		}
	{ name 'Mic2 Capture Volume'			value 0						}
	{ name 'Mic1 Capture Volume'			value 0						}
	{ name 'DAI Mode'				value 'DAI 0'				}
	{ name 'ADC Data Select'			value Stereo				}
	{ name 'ROUT2 Phase'				value Inverted				}
	{ name 'Mic Selection Mux'			value 'Mic 1'				}
	{ name 'Rx Mixer'				value 'RXP - RXN'			}
	{ name 'Line Mixer'				value 'Line 1 + 2'			}
	{ name 'Line Mono Mux'				value 'Line Mix'			}
	{ name 'Line Right Mux'				value 'Rx Mix'				}
	{ name 'Line Left Mux'				value 'Rx Mix'				}
	{ name 'ALC Mixer Line Capture Switch'		value false					}
	{ name 'ALC Mixer Mic2 Capture Switch'		value false					}
	{ name 'ALC Mixer Mic1 Capture Switch'		value false					}
	{ name 'ALC Mixer Rx Capture Switch'		value false					}
	{ name 'Mic Sidetone Mux'			value 'Left PGA'			}
	{ name 'Capture Right Mux'			value PGA					}
	{ name 'Capture Left Mux'			value PGA					}
	{ name 'Capture Right Mixer'			value Stereo				}
	{ name 'Capture Left Mixer'			value Stereo				}
	{ name 'Playback Mixer Voice Capture Sw'	value false					}
	{ name 'Playback Mixer Left Capture Swi'	value false					}
	{ name 'Playback Mixer Right Capture Sw'	value false					}
	{ name 'Out4 Mux'				value VREF					}
	{ name 'Out3 Mux'				value VREF					}
	{ name 'Mono 2 Mux'				value 'Inverted Mono 1'		}
	{ name 'Mono Mixer Left Playback Switch'	value false					}
	{ name 'Mono Mixer Right Playback Switc'	value false					}
	{ name 'Mono Mixer Voice Playback Switc'	value false					}
	{ name 'Mono Mixer Sidetone Playback Sw'	value false					}
	{ name 'Mono Mixer Bypass Playback Swit'	value false					}
	{ name 'Right Mixer Voice Playback Swit'	value false					}
	{ name 'Right Mixer Sidetone Playback S'	value false					}
	{ name 'Right Mixer Right Playback Swit'	value true					}
	{ name 'Right Mixer Bypass Playback Swi'	value false					}
	{ name 'Left Mixer Voice Playback Switc'	value false					}
	{ name 'Left Mixer Sidetone Playback Sw'	value false					}
	{ name 'Left Mixer Left Playback Switch'	value true					}
	{ name 'Left Mixer Bypass Playback Swit'	value false					}
	{ name 'DAPM Stereo Out Switch'			value true					}
	{ name 'DAPM GSM Line Out Switch'		value false					}
	{ name 'DAPM GSM Line In Switch'		value false					}
	{ name 'DAPM Headset Mic Switch'		value false					}
	{ name 'DAPM Handset Mic Switch'		value false					}
	{ name 'DAPM Handset Spk Switch'		value false					}
	{ name 'Amp State Switch'			value true					}
	{ name 'Amp Spk Switch'				value true					}



I'm now trying to see if I can monitor and capture what it is doing via. 
JTAG. It doesn't look like this is possible, though. All is ok up until 
it goes into suspend. I can ctrl-c and see whats going on:

Program received signal SIGINT, Interrupt.
s3c24xx_default_idle () at include/asm/arch/system.h:41
41        for (i = 0; i < 50; i++) {
(gdb) bt
#0  s3c24xx_default_idle () at include/asm/arch/system.h:41
#1  0xc0063278 in default_idle () at include/asm/arch/system.h:56
#2  0xc0062fb8 in cpu_idle () at arch/arm/kernel/process.c:170
#3  0xc0329b2c in rest_init () at init/main.c:453
#4  0xc0008d18 in start_kernel () at init/main.c:648
#5  0x30008034 in ?? ()
(gdb) c
Continuing.

but when it suspends I get

timeout waiting for SYSCOMP & DBGACK, last DBG_STATUS: 0
timeout waiting for SYSCOMP & DBGACK, last DBG_STATUS: 0
timeout waiting for SYSCOMP & DBGACK, last DBG_STATUS: 0
timeout waiting for SYSCOMP & DBGACK, last DBG_STATUS: 0

Program received signal SIGTRAP, Trace/breakpoint trap.
0xffffffec in ?? ()

and then its pretty much dead.