diff options
Diffstat (limited to 'target/linux/brcm2708/patches-4.19/950-0064-ASoC-pcm512x-implement-set_tdm_slot-interface.patch')
-rw-r--r-- | target/linux/brcm2708/patches-4.19/950-0064-ASoC-pcm512x-implement-set_tdm_slot-interface.patch | 80 |
1 files changed, 80 insertions, 0 deletions
diff --git a/target/linux/brcm2708/patches-4.19/950-0064-ASoC-pcm512x-implement-set_tdm_slot-interface.patch b/target/linux/brcm2708/patches-4.19/950-0064-ASoC-pcm512x-implement-set_tdm_slot-interface.patch new file mode 100644 index 0000000000..e656c05a55 --- /dev/null +++ b/target/linux/brcm2708/patches-4.19/950-0064-ASoC-pcm512x-implement-set_tdm_slot-interface.patch @@ -0,0 +1,80 @@ +From 5fd7bb26ef791a7da1c0573b980ab4fe6b9c2641 Mon Sep 17 00:00:00 2001 +From: Matthias Reichl <hias@horus.com> +Date: Thu, 22 Feb 2018 11:55:06 +0100 +Subject: [PATCH] ASoC: pcm512x: implement set_tdm_slot interface + +PCM512x can accept data padded with additional BCLK cycles +but the driver currently lacks an interface to configure this. + +This leads to the problem that S24_LE format in master mode +can result in non-integer clock divisors and pcm512x running +at a rather off rate. + +For example 48kHz with 48fs BCLK and SCLK at 24.576MHz uses +a divisor of 10 (rounded down from 10.6666) and results in a +51.2kHz LRCLK. With 64fs BCLK a divisor of 8 is used and +LRCLK runs at exactly 48kHz. + +Fix this by providing a minimal set_tdm_slot implementation +so machine drivers can optionally configure custom BCLK ratios. + +Signed-off-by: Matthias Reichl <hias@horus.com> +--- + sound/soc/codecs/pcm512x.c | 28 +++++++++++++++++++++++++++- + 1 file changed, 27 insertions(+), 1 deletion(-) + +--- a/sound/soc/codecs/pcm512x.c ++++ b/sound/soc/codecs/pcm512x.c +@@ -53,6 +53,7 @@ struct pcm512x_priv { + unsigned long overclock_pll; + unsigned long overclock_dac; + unsigned long overclock_dsp; ++ int lrclk_div; + }; + + /* +@@ -851,7 +852,10 @@ static int pcm512x_set_dividers(struct s + int fssp; + int gpio; + +- lrclk_div = snd_soc_params_to_frame_size(params); ++ if (pcm512x->lrclk_div) ++ lrclk_div = pcm512x->lrclk_div; ++ else ++ lrclk_div = snd_soc_params_to_frame_size(params); + if (lrclk_div == 0) { + dev_err(dev, "No LRCLK?\n"); + return -EINVAL; +@@ -1319,10 +1323,32 @@ static int pcm512x_set_fmt(struct snd_so + return 0; + } + ++static int pcm512x_set_tdm_slot(struct snd_soc_dai *dai, ++ unsigned int tx_mask, unsigned int rx_mask, ++ int slots, int width) ++{ ++ struct snd_soc_component *component = dai->component; ++ struct pcm512x_priv *pcm512x = snd_soc_component_get_drvdata(component); ++ ++ switch (slots) { ++ case 0: ++ pcm512x->lrclk_div = 0; ++ return 0; ++ case 2: ++ if (tx_mask != 0x03 || rx_mask != 0x03) ++ return -EINVAL; ++ pcm512x->lrclk_div = slots * width; ++ return 0; ++ default: ++ return -EINVAL; ++ } ++} ++ + static const struct snd_soc_dai_ops pcm512x_dai_ops = { + .startup = pcm512x_dai_startup, + .hw_params = pcm512x_hw_params, + .set_fmt = pcm512x_set_fmt, ++ .set_tdm_slot = pcm512x_set_tdm_slot, + }; + + static struct snd_soc_dai_driver pcm512x_dai = { |