[PPC,SOUND] Fix audio gpio state detection

[Olaf Hering]

 On Mon, Feb 13, Benjamin Herrenschmidt wrote:

> On Sat, 2006-02-11 at 17:10 +0100, Andreas Schwab wrote:
> > When booting with line out or headphone plugged, you won't hear anything.
> > The problem is that after reset all channels are muted, but the actual
> > value of the gpio port doesn't exactly match the active_val settings as
> > expected by check_audio_gpio.  For example, the line_mute port is set to
> > 7, but check_audio_gpio would expect 0xd or 0xf, thus its return value
> > indicates that it is not active, even though it is.  AFAICS only looking
> > at the low bit is enough to determine whether the port is active.
> > 
> > Signed-off-by: Andreas Schwab <schwab at suse.de>
> > 
> > Index: linux-2.6.16-rc2/sound/ppc/tumbler.c
> > ===================================================================
> > --- linux-2.6.16-rc2.orig/sound/ppc/tumbler.c	2006-02-03 19:43:50.000000000 +0100
> > +++ linux-2.6.16-rc2/sound/ppc/tumbler.c	2006-02-11 03:46:30.000000000 +0100
> > @@ -207,7 +207,7 @@ static int check_audio_gpio(struct pmac_
> >  
> >  	ret = do_gpio_read(gp);
> >  
> > -	return (ret & 0xd) == (gp->active_val & 0xd);
> > +	return (ret & 0x1) == (gp->active_val & 0x1);
> >  }
> >  
> >  static int read_audio_gpio(struct pmac_gpio *gp)

This (sort of) breaks PowerMac3,4 (69 (PowerMac G4 Silver)). I have to
force it on up to now, but with this patch the internal speaker will not
work with or without my patch to force it on.

I get these values:

check_audio_gpio gp c040fc14 addr 0000006f ret 00000007
check_audio_gpio gp c040fbfc addr 00000070 ret 00000004

With speakers plugged in, both give 0x07

/proc/device-tree/pci at f2000000/mac-io at 17/gpio at 50:
linux,device     cfdc7808
name             "gpio"
linux,phandle    ff90fcd0
reg              00000050 00000030
built-in        
device_type      "gpio"

/proc/device-tree/pci at f2000000/mac-io at 17/gpio at 50/extint-gpio16:
name             "extint-gpio16"
linux,phandle    ff910a00
interrupt-parent ff90fa80
interrupts       0000003e 00000000
AAPL,address     80000068
built-in        
one-wire-bus     "speaker-id"
AAPL,driver-name ".DallasDriver"
compatible       "keywest-gpio16"
device_type      "extint-gpio16"

/proc/device-tree/pci at f2000000/mac-io at 17/gpio at 50/extint-gpio15:
name             "extint-gpio15"
linux,phandle    ff9107f8
interrupt-parent ff90fa80
interrupts       0000003d 00000000
AAPL,address     80000067
built-in        
compatible       "keywest-gpio15"
device_type      "extint-gpio15"

/proc/device-tree/pci at f2000000/mac-io at 17/gpio at 50/gpio11:
name             "gpio11"
linux,phandle    ff9105f8
AAPL,address     80000075
built-in        
audio-gpio-active-state 00000000
audio-gpio       "audio-hw-reset"
compatible       "keywest-11"
device_type      "gpio11"

/proc/device-tree/pci at f2000000/mac-io at 17/gpio at 50/gpio6:
name             "gpio6"
linux,phandle    ff910400
AAPL,address     80000070
built-in        
audio-gpio-active-state 00000000
audio-gpio       "amp-mute"
compatible       "keywest-6"
device_type      "gpio6"

/proc/device-tree/pci at f2000000/mac-io at 17/gpio at 50/gpio5:
name             "gpio5"
linux,phandle    ff910208
AAPL,address     8000006f
built-in        
audio-gpio-active-state 00000000
audio-gpio       "headphone-mute"
compatible       "keywest-5"
device_type      "gpio5"

/proc/device-tree/pci at f2000000/mac-io at 17/gpio at 50/programmer-switch:
name             "programmer-switch"
linux,phandle    ff910058
interrupt-parent ff90fa80
interrupts       00000037 00000000
built-in        
device_type      "programmer-switch"

/proc/device-tree/pci at f2000000/mac-io at 17/gpio at 50/extint-gpio1:
name             "extint-gpio1"
linux,phandle    ff90fe38
AAPL,interrupt-priorities 00000001
interrupt-parent ff90fa80
interrupts       0000002f 00000001
built-in        
compatible       "keywest-gpio1"
device_type      "extint-gpio1"