[alsa-devel] [PATCH 02/11] ASoC: rt5651: Remove is_sys_clk_from_pll, it has ordering issues

[Hans de Goede]

dapm_power_widgets() first builds a list of which widgets to power-up
before actually powering any of them up. For dapm-supply widgets their
connected method, in our case is_sys_clk_from_pll() get called at this
point.

Before this commit is_sys_clk_from_pll() was looking at the actually
selected clock in the RT5651_GBL_CLK register. But the sysclk itself is
selected by another dapm-supply (the "Platform Clock" supply in the
machine driver) and any changes to that supply part of the same power-
transition get executed after building the list, causing
is_sys_clk_from_pll() to return the wrong value.

This sometimes leads to the PWR_PLL bit not getting set even though we
have configured an active audio chain and RT5651_GBL_CLK does point to
PLL1 as the sysclk-source.

Note that even if we do not have an active audio chain we should still keep
the PWR_PLL bit set if PLL1 is our sysclk-source, because we must always
have a working sysclk-source, otherwise e.g. jack-detection will not work.

If we don't have an active audio-chain then the machine-driver should
switch the sysclk-source to the RCCLK and if does not then that is a
machine-driver (or UCM config) problem and not something we should try
to work around by disabling our sysclk-source and breaking jack-detect.

TL;DR: The PLL1-supply must always be powered up when PLL1 is the sysclk
source and we can simply set the RT5651_PWR_PLL bit when selecting PLL1.

Signed-off-by: Hans de Goede <hdegoede at redhat.com>
---
Note that many of the other rt56?? drivers have the same
is_sys_clk_from_pll() stuff and may need similar fixes.
---
 sound/soc/codecs/rt5651.c | 25 +++++--------------------
 1 file changed, 5 insertions(+), 20 deletions(-)

diff --git a/sound/soc/codecs/rt5651.c b/sound/soc/codecs/rt5651.c
index c5d19a80506b..a48278f6205d 100644
--- a/sound/soc/codecs/rt5651.c
+++ b/sound/soc/codecs/rt5651.c
@@ -393,20 +393,6 @@ static int set_dmic_clk(struct snd_soc_dapm_widget *w,
 	return idx;
 }
 
-static int is_sysclk_from_pll(struct snd_soc_dapm_widget *source,
-			 struct snd_soc_dapm_widget *sink)
-{
-	struct snd_soc_codec *codec = snd_soc_dapm_to_codec(source->dapm);
-	unsigned int val;
-
-	val = snd_soc_read(codec, RT5651_GLB_CLK);
-	val &= RT5651_SCLK_SRC_MASK;
-	if (val == RT5651_SCLK_SRC_PLL1)
-		return 1;
-	else
-		return 0;
-}
-
 /* Digital Mixer */
 static const struct snd_kcontrol_new rt5651_sto1_adc_l_mix[] = {
 	SOC_DAPM_SINGLE("ADC1 Switch", RT5651_STO1_ADC_MIXER,
@@ -878,8 +864,6 @@ static const struct snd_soc_dapm_widget rt5651_dapm_widgets[] = {
 	SND_SOC_DAPM_SUPPLY_S("ADC ASRC", 1, RT5651_PLL_MODE_2,
 			      11, 0, NULL, 0),
 
-	SND_SOC_DAPM_SUPPLY("PLL1", RT5651_PWR_ANLG2,
-			RT5651_PWR_PLL_BIT, 0, NULL, 0),
 	/* Input Side */
 	SND_SOC_DAPM_SUPPLY("JD Power", RT5651_PWR_ANLG2,
 		RT5651_PWM_JD_M_BIT, 0, NULL, 0),
@@ -1162,7 +1146,6 @@ static const struct snd_soc_dapm_route rt5651_dapm_routes[] = {
 	{"Stereo1 ADC MIXL", "ADC1 Switch", "Stereo1 ADC L1 Mux"},
 	{"Stereo1 ADC MIXL", "ADC2 Switch", "Stereo1 ADC L2 Mux"},
 	{"Stereo1 ADC MIXL", NULL, "Stereo1 Filter"},
-	{"Stereo1 Filter", NULL, "PLL1", is_sysclk_from_pll},
 	{"Stereo1 Filter", NULL, "ADC ASRC"},
 
 	{"Stereo1 ADC MIXR", "ADC1 Switch", "Stereo1 ADC R1 Mux"},
@@ -1172,7 +1155,6 @@ static const struct snd_soc_dapm_route rt5651_dapm_routes[] = {
 	{"Stereo2 ADC MIXL", "ADC1 Switch", "Stereo2 ADC L1 Mux"},
 	{"Stereo2 ADC MIXL", "ADC2 Switch", "Stereo2 ADC L2 Mux"},
 	{"Stereo2 ADC MIXL", NULL, "Stereo2 Filter"},
-	{"Stereo2 Filter", NULL, "PLL1", is_sysclk_from_pll},
 	{"Stereo2 Filter", NULL, "ADC ASRC"},
 
 	{"Stereo2 ADC MIXR", "ADC1 Switch", "Stereo2 ADC R1 Mux"},
@@ -1239,10 +1221,8 @@ static const struct snd_soc_dapm_route rt5651_dapm_routes[] = {
 	{"PDM R Mux", "DD MIX", "DAC MIXR"},
 
 	{"DAC L1", NULL, "Stereo DAC MIXL"},
-	{"DAC L1", NULL, "PLL1", is_sysclk_from_pll},
 	{"DAC L1", NULL, "DAC L1 Power"},
 	{"DAC R1", NULL, "Stereo DAC MIXR"},
-	{"DAC R1", NULL, "PLL1", is_sysclk_from_pll},
 	{"DAC R1", NULL, "DAC R1 Power"},
 
 	{"DD MIXL", "DAC L1 Switch", "DAC MIXL"},
@@ -1438,6 +1418,7 @@ static int rt5651_set_dai_sysclk(struct snd_soc_dai *dai,
 	struct snd_soc_codec *codec = dai->codec;
 	struct rt5651_priv *rt5651 = snd_soc_codec_get_drvdata(codec);
 	unsigned int reg_val = 0;
+	unsigned int pll_bit = 0;
 
 	if (freq == rt5651->sysclk && clk_id == rt5651->sysclk_src)
 		return 0;
@@ -1448,6 +1429,7 @@ static int rt5651_set_dai_sysclk(struct snd_soc_dai *dai,
 		break;
 	case RT5651_SCLK_S_PLL1:
 		reg_val |= RT5651_SCLK_SRC_PLL1;
+		pll_bit |= RT5651_PWR_PLL;
 		break;
 	case RT5651_SCLK_S_RCCLK:
 		reg_val |= RT5651_SCLK_SRC_RCCLK;
@@ -1456,6 +1438,9 @@ static int rt5651_set_dai_sysclk(struct snd_soc_dai *dai,
 		dev_err(codec->dev, "Invalid clock id (%d)\n", clk_id);
 		return -EINVAL;
 	}
+
+	snd_soc_update_bits(codec, RT5651_PWR_ANLG2,
+		RT5651_PWR_PLL, pll_bit);
 	snd_soc_update_bits(codec, RT5651_GLB_CLK,
 		RT5651_SCLK_SRC_MASK, reg_val);
 	rt5651->sysclk = freq;
-- 
2.14.3