Hi Mark,
On 07/12/2013 04:42 PM, Mark Brown wrote:
On Fri, Jul 12, 2013 at 03:00:26PM +0800, Bo Shen wrote:
I try to add the following two line in wm8904_set_bias_level into "case SND_SOC_BIAS_ON", it doesn't work. ---8>--- @@ -1832,9 +1834,12 @@ static int wm8904_set_bias_level(struct snd_soc_codec *codec,
switch (level) { case SND_SOC_BIAS_ON:
regcache_cache_only(wm8904->regmap, false);regcache_sync(wm8904->regmap); break;---<8---
That's far too late to be doing that, the device is already supposed to be powered and running - you can see the device is doing this already in the transition from _OFF to _STANDBY which is where it should happen.
However, If I comment the regcache_cache_only(wm8904->regmap, true) as following, then it play OK. ---8>--- @@ -2232,7 +2239,7 @@ static int wm8904_i2c_probe(struct i2c_client *i2c, WM8904_POBCTRL, 0);
/* Can leave the device powered off until we need it */
regcache_cache_only(wm8904->regmap, true);
// regcache_cache_only(wm8904->regmap, true);---<8---
So, any clue for this issue?
The device is supposed to be idle_bias_off so sitting in _BIAS_OFF when not in use, this should mean a transition to _STANDBY as part of the power up sequence which should reenable interaction with the device. Check to see why that is not happening - _OFF should be the default bias level as well.
Do you mean the system boot up the device should be in _BIAS_OFF state?
I add debug info to set_bias_level function, and don't see this is called when system boot up. When I run aplay command, it call from _STANDBY to _ON, not _OFF, after show the error message, it call from _PREPARE to _OFF.
---8>--- # aplay 44.1k_16bit_stereo.wav Playing WAVE '44.1k_16bit_stereo.wav' : Signed 16 bit Little Endian, Rate 44100 Hz, Stereo
leve is: 1 leve is: 2 leve is: 3
aplay: pcm_write:1737: write error: Input/output error # >>>>>> leve is: 2
leve is: 1 leve is: 0
---<8---
Best Regards, Bo Shen