| Message ID | 20220606154441.20848-2-lukma@denx.de (mailing list archive) |
|---|---|
| State | New, archived |
| Headers | show |
| Series | [1/3] ASoC: wm8940: Remove warning when no plat data | expand |
On Mon, Jun 06, 2022 at 05:44:40PM +0200, Lukasz Majewski wrote: > Without this change, the wm8940 driver is not working when > set_sysclk callback (wm8940_set_dai_sysclk) is called with > freqency not listed in the switch clause. > This change adjusts this driver to allow non-standard frequency > set (just after the boot) being adjusted afterwards by the sound > system core code. I don't entirely follow the above - in what way might the core adjust the clocking, and why would we want to allow the use of invalid clocks? Surely that just makes error checking worse. > Code in this commit is based on previous change done for wm8974 > (SHA1: 51b2bb3f2568e6d9d81a001d38b8d70c2ba4af99). Please include human readable descriptions of things like commits and issues being discussed in e-mail in your mails, this makes them much easier for humans to read especially when they have no internet access. I do frequently catch up on my mail on flights or while otherwise travelling so this is even more pressing for me than just being about making things a bit easier to read.
Hi Mark, > On Mon, Jun 06, 2022 at 05:44:40PM +0200, Lukasz Majewski wrote: > > Without this change, the wm8940 driver is not working when > > set_sysclk callback (wm8940_set_dai_sysclk) is called with > > freqency not listed in the switch clause. > > > This change adjusts this driver to allow non-standard frequency > > set (just after the boot) being adjusted afterwards by the sound > > system core code. > > I don't entirely follow the above - in what way might the core adjust > the clocking, and why would we want to allow the use of invalid > clocks? Surely that just makes error checking worse. Hmm, it is a bit complicated. When I enabed wm8940 support in mainline - the first call to wm8940_set_dai_sysclk (the set_sysclk callback) required mclk = 11997070 frequency. With the current code [1] the initialization of the codec returns -EINVAL and the codec is not supported in the system: asoc-simple-card: probe of sound failed with error -22 The approach used in this patch set to fix the above issue is based on one already present in-tree for wm8974 codec. > > > Code in this commit is based on previous change done for wm8974 > > (SHA1: 51b2bb3f2568e6d9d81a001d38b8d70c2ba4af99). > > Please include human readable descriptions of things like commits and > issues being discussed in e-mail in your mails, this makes them much > easier for humans to read especially when they have no internet > access. Ok, I will add some more verbose description. The aforementioned SHA1 is referring to commit already in-tree, so you would find it easily even without the Internet. > I do frequently catch up on my mail on flights or while > otherwise travelling so this is even more pressing for me than just > being about making things a bit easier to read. +1 Links: [1] - https://elixir.bootlin.com/linux/v5.18.1/source/sound/soc/codecs/wm8940.c#L614 Best regards, Lukasz Majewski -- DENX Software Engineering GmbH, Managing Director: Wolfgang Denk HRB 165235 Munich, Office: Kirchenstr.5, D-82194 Groebenzell, Germany Phone: (+49)-8142-66989-59 Fax: (+49)-8142-66989-80 Email: lukma@denx.de
On Tue, Jun 07, 2022 at 02:13:09PM +0200, Lukasz Majewski wrote: > > On Mon, Jun 06, 2022 at 05:44:40PM +0200, Lukasz Majewski wrote: > > I don't entirely follow the above - in what way might the core adjust > > the clocking, and why would we want to allow the use of invalid > > clocks? Surely that just makes error checking worse. > Hmm, it is a bit complicated. > When I enabed wm8940 support in mainline - the first call to > wm8940_set_dai_sysclk (the set_sysclk callback) required mclk = 11997070 > frequency. > With the current code [1] the initialization of the codec returns > -EINVAL and the codec is not supported in the system: > asoc-simple-card: probe of sound failed with error -22 Well, that looks like a bug in either simple-card or it's configuration which should be fixed then (you should probably use audio-graph-card for new things BTW). If a machine driver just randomly sets a clock rate that the system can't support and doesn't want then that's a problem, presuambly it's getting that rate from somewhere. Note that this is the machine driver trying to set a clock rate, not the core.
diff --git a/sound/soc/codecs/wm8940.c b/sound/soc/codecs/wm8940.c index 7cea54720436..6fb1c3780439 100644 --- a/sound/soc/codecs/wm8940.c +++ b/sound/soc/codecs/wm8940.c @@ -37,7 +37,9 @@ #include "wm8940.h" struct wm8940_priv { - unsigned int sysclk; + unsigned int mclk; + unsigned int fs; + struct regmap *regmap; }; @@ -387,17 +389,24 @@ static int wm8940_set_dai_fmt(struct snd_soc_dai *codec_dai, return 0; } +static int wm8940_update_clocks(struct snd_soc_dai *dai); static int wm8940_i2s_hw_params(struct snd_pcm_substream *substream, struct snd_pcm_hw_params *params, struct snd_soc_dai *dai) { struct snd_soc_component *component = dai->component; + struct wm8940_priv *wm8940 = snd_soc_component_get_drvdata(component); u16 iface = snd_soc_component_read(component, WM8940_IFACE) & 0xFD9F; u16 addcntrl = snd_soc_component_read(component, WM8940_ADDCNTRL) & 0xFFF1; u16 companding = snd_soc_component_read(component, WM8940_COMPANDINGCTL) & 0xFFDF; int ret; + wm8940->fs = params_rate(params); + ret = wm8940_update_clocks(dai); + if (ret) + return ret; + /* LoutR control */ if (substream->stream == SNDRV_PCM_STREAM_CAPTURE && params_channels(params) == 2) @@ -496,7 +505,6 @@ static int wm8940_set_bias_level(struct snd_soc_component *component, return ret; } } - /* ensure bufioen and biasen */ pwr_reg |= (1 << 2) | (1 << 3); /* set vmid to 300k for standby */ @@ -611,24 +619,6 @@ static int wm8940_set_dai_pll(struct snd_soc_dai *codec_dai, int pll_id, return 0; } -static int wm8940_set_dai_sysclk(struct snd_soc_dai *codec_dai, - int clk_id, unsigned int freq, int dir) -{ - struct snd_soc_component *component = codec_dai->component; - struct wm8940_priv *wm8940 = snd_soc_component_get_drvdata(component); - - switch (freq) { - case 11289600: - case 12000000: - case 12288000: - case 16934400: - case 18432000: - wm8940->sysclk = freq; - return 0; - } - return -EINVAL; -} - static int wm8940_set_dai_clkdiv(struct snd_soc_dai *codec_dai, int div_id, int div) { @@ -653,6 +643,79 @@ static int wm8940_set_dai_clkdiv(struct snd_soc_dai *codec_dai, return ret; } +static unsigned int wm8940_get_mclkdiv(unsigned int f_in, unsigned int f_out, + int *mclkdiv) +{ + unsigned int ratio = 2 * f_in / f_out; + + if (ratio <= 2) { + *mclkdiv = WM8940_MCLKDIV_1; + ratio = 2; + } else if (ratio == 3) { + *mclkdiv = WM8940_MCLKDIV_1_5; + } else if (ratio == 4) { + *mclkdiv = WM8940_MCLKDIV_2; + } else if (ratio <= 6) { + *mclkdiv = WM8940_MCLKDIV_3; + ratio = 6; + } else if (ratio <= 8) { + *mclkdiv = WM8940_MCLKDIV_4; + ratio = 8; + } else if (ratio <= 12) { + *mclkdiv = WM8940_MCLKDIV_6; + ratio = 12; + } else if (ratio <= 16) { + *mclkdiv = WM8940_MCLKDIV_8; + ratio = 16; + } else { + *mclkdiv = WM8940_MCLKDIV_12; + ratio = 24; + } + + return f_out * ratio / 2; +} + +static int wm8940_update_clocks(struct snd_soc_dai *dai) +{ + struct snd_soc_component *component = dai->component; + struct wm8940_priv *priv = snd_soc_component_get_drvdata(component); + unsigned int fs256; + unsigned int fpll = 0; + unsigned int f; + int mclkdiv; + + if (!priv->mclk || !priv->fs) + return 0; + + fs256 = 256 * priv->fs; + + f = wm8940_get_mclkdiv(priv->mclk, fs256, &mclkdiv); + if (f != priv->mclk) { + /* The PLL performs best around 90MHz */ + fpll = wm8940_get_mclkdiv(22500000, fs256, &mclkdiv); + } + + wm8940_set_dai_pll(dai, 0, 0, priv->mclk, fpll); + wm8940_set_dai_clkdiv(dai, WM8940_MCLKDIV, mclkdiv); + + return 0; +} + +static int wm8940_set_dai_sysclk(struct snd_soc_dai *dai, int clk_id, + unsigned int freq, int dir) +{ + struct snd_soc_component *component = dai->component; + struct wm8940_priv *priv = snd_soc_component_get_drvdata(component); + + if (dir != SND_SOC_CLOCK_IN) + return -EINVAL; + + priv->mclk = freq; + + return wm8940_update_clocks(dai); +} + + #define WM8940_RATES SNDRV_PCM_RATE_8000_48000 #define WM8940_FORMATS (SNDRV_PCM_FMTBIT_S8 | \
Without this change, the wm8940 driver is not working when set_sysclk callback (wm8940_set_dai_sysclk) is called with freqency not listed in the switch clause. This change adjusts this driver to allow non-standard frequency set (just after the boot) being adjusted afterwards by the sound system core code. Moreover, support for internal wm8940's PLL is provided, so it can generate clocks when HOST system is not able to do it. Code in this commit is based on previous change done for wm8974 (SHA1: 51b2bb3f2568e6d9d81a001d38b8d70c2ba4af99). Signed-off-by: Lukasz Majewski <lukma@denx.de> --- sound/soc/codecs/wm8940.c | 103 ++++++++++++++++++++++++++++++-------- 1 file changed, 83 insertions(+), 20 deletions(-)