* [PATCH v3] ASoC: wm9081: Use snd_soc_update_bits for read-modify-write
@ 2011-11-09 8:38 Axel Lin
2011-11-09 8:46 ` Axel Lin
0 siblings, 1 reply; 3+ messages in thread
From: Axel Lin @ 2011-11-09 8:38 UTC (permalink / raw)
To: linux-kernel; +Cc: Mark Brown, Dimitris Papastamos, Liam Girdwood, alsa-devel
Use snd_soc_update_bits for read-modify-write register access instead of
open-coding it using snd_soc_read and snd_soc_write
Signed-off-by: Axel Lin <axel.lin@gmail.com>
---
sound/soc/codecs/wm9081.c | 82 ++++++++++++++++++++-------------------------
1 files changed, 36 insertions(+), 46 deletions(-)
diff --git a/sound/soc/codecs/wm9081.c b/sound/soc/codecs/wm9081.c
index b491ae1..f032078 100644
--- a/sound/soc/codecs/wm9081.c
+++ b/sound/soc/codecs/wm9081.c
@@ -826,84 +826,75 @@ static const struct snd_soc_dapm_route wm9081_audio_paths[] = {
static int wm9081_set_bias_level(struct snd_soc_codec *codec,
enum snd_soc_bias_level level)
{
- u16 reg;
-
switch (level) {
case SND_SOC_BIAS_ON:
break;
case SND_SOC_BIAS_PREPARE:
/* VMID=2*40k */
- reg = snd_soc_read(codec, WM9081_VMID_CONTROL);
- reg &= ~WM9081_VMID_SEL_MASK;
- reg |= 0x2;
- snd_soc_write(codec, WM9081_VMID_CONTROL, reg);
+ snd_soc_update_bits(codec, WM9081_VMID_CONTROL,
+ WM9081_VMID_SEL_MASK, 0x2);
/* Normal bias current */
- reg = snd_soc_read(codec, WM9081_BIAS_CONTROL_1);
- reg &= ~WM9081_STBY_BIAS_ENA;
- snd_soc_write(codec, WM9081_BIAS_CONTROL_1, reg);
+ snd_soc_update_bits(codec, WM9081_BIAS_CONTROL_1,
+ WM9081_STBY_BIAS_ENA, 0);
break;
case SND_SOC_BIAS_STANDBY:
/* Initial cold start */
if (codec->dapm.bias_level == SND_SOC_BIAS_OFF) {
/* Disable LINEOUT discharge */
- reg = snd_soc_read(codec, WM9081_ANTI_POP_CONTROL);
- reg &= ~WM9081_LINEOUT_DISCH;
- snd_soc_write(codec, WM9081_ANTI_POP_CONTROL, reg);
+ snd_soc_update_bits(codec, WM9081_ANTI_POP_CONTROL,
+ WM9081_LINEOUT_DISCH, 0);
/* Select startup bias source */
- reg = snd_soc_read(codec, WM9081_BIAS_CONTROL_1);
- reg |= WM9081_BIAS_SRC | WM9081_BIAS_ENA;
- snd_soc_write(codec, WM9081_BIAS_CONTROL_1, reg);
+ snd_soc_update_bits(codec, WM9081_BIAS_CONTROL_1,
+ WM9081_BIAS_SRC | WM9081_BIAS_ENA,
+ WM9081_BIAS_SRC | WM9081_BIAS_ENA);
/* VMID 2*4k; Soft VMID ramp enable */
- reg = snd_soc_read(codec, WM9081_VMID_CONTROL);
- reg |= WM9081_VMID_RAMP | 0x6;
- snd_soc_write(codec, WM9081_VMID_CONTROL, reg);
+ snd_soc_update_bits(codec, WM9081_VMID_CONTROL,
+ WM9081_VMID_RAMP |
+ WM9081_VMID_SEL_MASK,
+ WM9081_VMID_RAMP | 0x6);
mdelay(100);
/* Normal bias enable & soft start off */
- reg &= ~WM9081_VMID_RAMP;
- snd_soc_write(codec, WM9081_VMID_CONTROL, reg);
+ snd_soc_update_bits(codec, WM9081_VMID_CONTROL,
+ WM9081_VMID_RAMP |
+ WM9081_VMID_SEL_MASK, 0);
/* Standard bias source */
- reg = snd_soc_read(codec, WM9081_BIAS_CONTROL_1);
- reg &= ~WM9081_BIAS_SRC;
- snd_soc_write(codec, WM9081_BIAS_CONTROL_1, reg);
+ snd_soc_update_bits(codec, WM9081_BIAS_CONTROL_1,
+ WM9081_BIAS_SRC, 0);
}
/* VMID 2*240k */
- reg = snd_soc_read(codec, WM9081_VMID_CONTROL);
- reg &= ~WM9081_VMID_SEL_MASK;
- reg |= 0x04;
- snd_soc_write(codec, WM9081_VMID_CONTROL, reg);
+ snd_soc_update_bits(codec, WM9081_VMID_CONTROL,
+ WM9081_VMID_SEL_MASK, 0x04);
/* Standby bias current on */
- reg = snd_soc_read(codec, WM9081_BIAS_CONTROL_1);
- reg |= WM9081_STBY_BIAS_ENA;
- snd_soc_write(codec, WM9081_BIAS_CONTROL_1, reg);
+ snd_soc_update_bits(codec, WM9081_BIAS_CONTROL_1,
+ WM9081_STBY_BIAS_ENA,
+ WM9081_STBY_BIAS_ENA);
break;
case SND_SOC_BIAS_OFF:
/* Startup bias source and disable bias */
- reg = snd_soc_read(codec, WM9081_BIAS_CONTROL_1);
- reg |= WM9081_BIAS_SRC;
- reg &= ~WM9081_BIAS_ENA;
- snd_soc_write(codec, WM9081_BIAS_CONTROL_1, reg);
+ snd_soc_update_bits(codec, WM9081_BIAS_CONTROL_1,
+ WM9081_BIAS_SRC | WM9081_BIAS_ENA,
+ WM9081_BIAS_SRC);
/* Disable VMID with soft ramping */
- reg = snd_soc_read(codec, WM9081_VMID_CONTROL);
- reg &= ~WM9081_VMID_SEL_MASK;
- reg |= WM9081_VMID_RAMP;
- snd_soc_write(codec, WM9081_VMID_CONTROL, reg);
+ snd_soc_update_bits(codec, WM9081_VMID_CONTROL,
+ WM9081_VMID_RAMP | WM9081_VMID_SEL_MASK,
+ WM9081_VMID_RAMP);
/* Actively discharge LINEOUT */
- reg = snd_soc_read(codec, WM9081_ANTI_POP_CONTROL);
- reg |= WM9081_LINEOUT_DISCH;
- snd_soc_write(codec, WM9081_ANTI_POP_CONTROL, reg);
+ snd_soc_update_bits(codec, WM9081_ANTI_POP_CONTROL,
+ WM9081_LINEOUT_DISCH,
+ WM9081_LINEOUT_DISCH);
break;
}
@@ -1291,11 +1282,10 @@ static int wm9081_probe(struct snd_soc_codec *codec)
wm9081_set_bias_level(codec, SND_SOC_BIAS_STANDBY);
/* Enable zero cross by default */
- reg = snd_soc_read(codec, WM9081_ANALOGUE_LINEOUT);
- snd_soc_write(codec, WM9081_ANALOGUE_LINEOUT, reg | WM9081_LINEOUTZC);
- reg = snd_soc_read(codec, WM9081_ANALOGUE_SPEAKER_PGA);
- snd_soc_write(codec, WM9081_ANALOGUE_SPEAKER_PGA,
- reg | WM9081_SPKPGAZC);
+ snd_soc_update_bits(codec, WM9081_ANALOGUE_LINEOUT,
+ WM9081_LINEOUTZC, WM9081_LINEOUTZC);
+ snd_soc_update_bits(codec, WM9081_ANALOGUE_SPEAKER_PGA,
+ WM9081_SPKPGAZC, WM9081_SPKPGAZC);
if (!wm9081->pdata.num_retune_configs) {
dev_dbg(codec->dev,
--
1.7.5.4
^ permalink raw reply related [flat|nested] 3+ messages in thread
* Re: [PATCH v3] ASoC: wm9081: Use snd_soc_update_bits for read-modify-write
2011-11-09 8:38 [PATCH v3] ASoC: wm9081: Use snd_soc_update_bits for read-modify-write Axel Lin
@ 2011-11-09 8:46 ` Axel Lin
2011-11-09 8:53 ` Axel Lin
0 siblings, 1 reply; 3+ messages in thread
From: Axel Lin @ 2011-11-09 8:46 UTC (permalink / raw)
To: linux-kernel; +Cc: Mark Brown, Dimitris Papastamos, Liam Girdwood, alsa-devel
> /* VMID 2*4k; Soft VMID ramp enable */
> - reg = snd_soc_read(codec, WM9081_VMID_CONTROL);
> - reg |= WM9081_VMID_RAMP | 0x6;
> - snd_soc_write(codec, WM9081_VMID_CONTROL, reg);
> + snd_soc_update_bits(codec, WM9081_VMID_CONTROL,
> + WM9081_VMID_RAMP |
> + WM9081_VMID_SEL_MASK,
> + WM9081_VMID_RAMP | 0x6);
>
> mdelay(100);
>
> /* Normal bias enable & soft start off */
> - reg &= ~WM9081_VMID_RAMP;
> - snd_soc_write(codec, WM9081_VMID_CONTROL, reg);
> + snd_soc_update_bits(codec, WM9081_VMID_CONTROL,
> + WM9081_VMID_RAMP |
> + WM9081_VMID_SEL_MASK, 0);
>
It's probably not trival why we need to clear WM9081_VMID_SEL_MASK bits here by
looking at the patch. Looking at original code, you will know current code
indeed clear WM9081_VMID_SEL_MASK bit here.
What current code does:
1. read WM9081_VMID_CONTROL register
2. write to WM9081_VMID_CONTROL register with setting WM9081_VMID_RAMP
bit and setting WM9081_VMID_SEL_MASK bits to 0x6 (VMID
2*4k; Soft VMID
ramp enable)
3. mdelay(100)
4. write to WM9081_VMID_CONTROL register with clearing
WM9081_VMID_RAMP bit.
Note: In this write, we do also clear WM9081_VMID_SEL_MASK
bits because the register
value of WM9081_VMID_SEL_MASK bits are clear when we read
in "step1".
In this case, the WM9081_VMID_SEL_MASK bits are clear
because we clear WM9081_VMID_SEL_MASK bits in SND_SOC_BIAS_OFF.
( The default value is also zero for WM9081_VMID_SEL_MASK bits. )
While converting to snd_soc_update_bits here we actually do one more read.
For the second call of snd_soc_update_bits, we need to explictly clear
WM9081_VMID_SEL_MASK bits.
Regards,
Axel
^ permalink raw reply [flat|nested] 3+ messages in thread
* Re: [PATCH v3] ASoC: wm9081: Use snd_soc_update_bits for read-modify-write
2011-11-09 8:46 ` Axel Lin
@ 2011-11-09 8:53 ` Axel Lin
0 siblings, 0 replies; 3+ messages in thread
From: Axel Lin @ 2011-11-09 8:53 UTC (permalink / raw)
To: linux-kernel; +Cc: Mark Brown, Dimitris Papastamos, Liam Girdwood, alsa-devel
2011/11/9 Axel Lin <axel.lin@gmail.com>:
>> /* VMID 2*4k; Soft VMID ramp enable */
>> - reg = snd_soc_read(codec, WM9081_VMID_CONTROL);
>> - reg |= WM9081_VMID_RAMP | 0x6;
>> - snd_soc_write(codec, WM9081_VMID_CONTROL, reg);
>> + snd_soc_update_bits(codec, WM9081_VMID_CONTROL,
>> + WM9081_VMID_RAMP |
>> + WM9081_VMID_SEL_MASK,
>> + WM9081_VMID_RAMP | 0x6);
>>
>> mdelay(100);
>>
>> /* Normal bias enable & soft start off */
>> - reg &= ~WM9081_VMID_RAMP;
oh.. wait. so original code does not clear WM9081_VMID_SEL_MASK bits here.
My bad. Don't know why I always think WM9081_VMID_SEL_MASK bits are
cleared here.
Will send a new version soon.
>> - snd_soc_write(codec, WM9081_VMID_CONTROL, reg);
>> + snd_soc_update_bits(codec, WM9081_VMID_CONTROL,
>> + WM9081_VMID_RAMP |
>> + WM9081_VMID_SEL_MASK, 0);
>>
^ permalink raw reply [flat|nested] 3+ messages in thread
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2011-11-09 8:38 [PATCH v3] ASoC: wm9081: Use snd_soc_update_bits for read-modify-write Axel Lin
2011-11-09 8:46 ` Axel Lin
2011-11-09 8:53 ` Axel Lin
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