[PATCH v3 10/13] ASoC: tegra: Add audio graph based card driver
Sameer Pujar
spujar at nvidia.com
Thu Oct 1 19:33:04 CEST 2020
Add Tegra audio machine driver which is based on generic audio graph card
driver. It re-uses most of the common stuff from audio graph driver and
uses the same DT binding. Required Tegra specific customizations are done
in the driver.
Details on the customizations done:
- Update PLL rates at runtime: Tegra HW supports multiple sample rates
(multiples of 8x and 11.025x) and both of these groups require different
PLL rates. Hence there is a requirement to update this at runtime.
This is achieved by providing a custom 'snd_soc_ops' and in hw_param()
callback PLL rate is updated as per the sample rate.
- Internal structure 'tegra_audio_graph_data' is used to maintain clock
handles of PLL.
- The 'force_dpcm' flag is set to use DPCM for all DAI links.
- The 'component_chaining' flag is set to use DPCM with component model.
Signed-off-by: Sameer Pujar <spujar at nvidia.com>
---
sound/soc/tegra/Kconfig | 9 +
sound/soc/tegra/Makefile | 2 +
sound/soc/tegra/tegra_audio_graph_card.c | 291 +++++++++++++++++++++++++++++++
3 files changed, 302 insertions(+)
create mode 100644 sound/soc/tegra/tegra_audio_graph_card.c
diff --git a/sound/soc/tegra/Kconfig b/sound/soc/tegra/Kconfig
index 3d91bd3..9959605 100644
--- a/sound/soc/tegra/Kconfig
+++ b/sound/soc/tegra/Kconfig
@@ -118,6 +118,15 @@ config SND_SOC_TEGRA210_ADMAIF
channel. Buffer size is configurable for each ADMAIIF channel.
Say Y or M if you want to add support for Tegra210 ADMAIF module.
+config SND_SOC_TEGRA_AUDIO_GRAPH_CARD
+ tristate "Audio Graph Card based Tegra driver"
+ depends on SND_AUDIO_GRAPH_CARD
+ help
+ Config to enable Tegra audio machine driver based on generic
+ audio graph driver. It is a thin driver written to customize
+ few things for Tegra audio. Most of the code is re-used from
+ audio graph driver and the same DT bindings are used.
+
config SND_SOC_TEGRA_RT5640
tristate "SoC Audio support for Tegra boards using an RT5640 codec"
depends on SND_SOC_TEGRA && I2C && GPIOLIB
diff --git a/sound/soc/tegra/Makefile b/sound/soc/tegra/Makefile
index 60040a0..b17dd6e 100644
--- a/sound/soc/tegra/Makefile
+++ b/sound/soc/tegra/Makefile
@@ -38,6 +38,7 @@ snd-soc-tegra-trimslice-objs := trimslice.o
snd-soc-tegra-alc5632-objs := tegra_alc5632.o
snd-soc-tegra-max98090-objs := tegra_max98090.o
snd-soc-tegra-sgtl5000-objs := tegra_sgtl5000.o
+snd-soc-tegra-audio-graph-card-objs := tegra_audio_graph_card.o
obj-$(CONFIG_SND_SOC_TEGRA_RT5640) += snd-soc-tegra-rt5640.o
obj-$(CONFIG_SND_SOC_TEGRA_RT5677) += snd-soc-tegra-rt5677.o
@@ -48,3 +49,4 @@ obj-$(CONFIG_SND_SOC_TEGRA_TRIMSLICE) += snd-soc-tegra-trimslice.o
obj-$(CONFIG_SND_SOC_TEGRA_ALC5632) += snd-soc-tegra-alc5632.o
obj-$(CONFIG_SND_SOC_TEGRA_MAX98090) += snd-soc-tegra-max98090.o
obj-$(CONFIG_SND_SOC_TEGRA_SGTL5000) += snd-soc-tegra-sgtl5000.o
+obj-$(CONFIG_SND_SOC_TEGRA_AUDIO_GRAPH_CARD) += snd-soc-tegra-audio-graph-card.o
diff --git a/sound/soc/tegra/tegra_audio_graph_card.c b/sound/soc/tegra/tegra_audio_graph_card.c
new file mode 100644
index 0000000..cfbd3f0
--- /dev/null
+++ b/sound/soc/tegra/tegra_audio_graph_card.c
@@ -0,0 +1,291 @@
+// SPDX-License-Identifier: GPL-2.0-only
+//
+// tegra_audio_graph_card.c - Audio Graph based Tegra Machine Driver
+//
+// Copyright (c) 2020 NVIDIA CORPORATION. All rights reserved.
+
+#include <linux/math64.h>
+#include <linux/module.h>
+#include <linux/of_device.h>
+#include <linux/platform_device.h>
+#include <sound/graph_card.h>
+#include <sound/pcm_params.h>
+
+#define MAX_PLLA_OUT0_DIV 128
+
+enum srate_type {
+ /*
+ * Sample rates multiple of 8000 Hz and below are supported:
+ * ( 8000, 16000, 32000, 48000, 96000, 192000 Hz )
+ */
+ x8_RATE,
+
+ /*
+ * Sample rates multiple of 11025 Hz and below are supported:
+ * ( 11025, 22050, 44100, 88200, 176400 Hz )
+ */
+ x11_RATE,
+
+ NUM_RATE_TYPE,
+};
+
+struct tegra_audio_graph_data {
+ struct clk *clk_plla_out0;
+ struct clk *clk_plla;
+};
+
+struct tegra_audio_chip_data {
+ unsigned int plla_out0_rates[NUM_RATE_TYPE];
+ unsigned int plla_rates[NUM_RATE_TYPE];
+};
+
+/* Setup PLL clock as per the given sample rate */
+static int tegra_audio_graph_update_pll(struct snd_pcm_substream *substream,
+ struct snd_pcm_hw_params *params)
+{
+ struct snd_soc_pcm_runtime *rtd = asoc_substream_to_rtd(substream);
+ struct asoc_simple_priv *priv = snd_soc_card_get_drvdata(rtd->card);
+ struct device *dev = rtd->card->dev;
+ struct tegra_audio_graph_data *graph_data =
+ (struct tegra_audio_graph_data *)priv->data;
+ struct tegra_audio_chip_data *chip_data =
+ (struct tegra_audio_chip_data *)of_device_get_match_data(dev);
+ unsigned int srate = params_rate(params);
+ unsigned int plla_rate, plla_out0_rate, bclk;
+ int err;
+
+ /* There is nothing to configure */
+ if (!chip_data)
+ return 0;
+
+ switch (srate) {
+ case 11025:
+ case 22050:
+ case 44100:
+ case 88200:
+ case 176400:
+ plla_out0_rate = chip_data->plla_out0_rates[x11_RATE];
+ plla_rate = chip_data->plla_rates[x11_RATE];
+ break;
+ case 8000:
+ case 16000:
+ case 32000:
+ case 48000:
+ case 96000:
+ case 192000:
+ plla_out0_rate = chip_data->plla_out0_rates[x8_RATE];
+ plla_rate = chip_data->plla_rates[x8_RATE];
+ break;
+ default:
+ dev_err(rtd->card->dev, "Unsupported sample rate %u\n",
+ srate);
+ return -EINVAL;
+ }
+
+ /*
+ * Below is the clock relation:
+ *
+ * PLLA
+ * |
+ * |--> PLLA_OUT0
+ * |
+ * |---> I2S modules
+ * |
+ * |---> DMIC modules
+ * |
+ * |---> DSPK modules
+ *
+ *
+ * Default PLLA_OUT0 rate might be too high when I/O is running
+ * at minimum PCM configurations. This may result in incorrect
+ * clock rates and glitchy audio. The maximum divider is 128
+ * and any thing higher than that won't work. Thus reduce PLLA_OUT0
+ * to work for lower configurations.
+ *
+ * This problem is seen for I2S only, as DMIC and DSPK minimum
+ * clock requirements are under allowed divider limits.
+ */
+ bclk = srate * params_channels(params) * params_width(params);
+ if (div_u64(plla_out0_rate, bclk) > MAX_PLLA_OUT0_DIV)
+ plla_out0_rate >>= 1;
+
+ dev_dbg(rtd->card->dev,
+ "Update clock rates: PLLA(= %u Hz) and PLLA_OUT0(= %u Hz)\n",
+ plla_rate, plla_out0_rate);
+
+ /* Set PLLA rate */
+ err = clk_set_rate(graph_data->clk_plla, plla_rate);
+ if (err) {
+ dev_err(rtd->card->dev,
+ "Can't set plla rate for %u, err: %d\n",
+ plla_rate, err);
+ return err;
+ }
+
+ /* Set PLLA_OUT0 rate */
+ err = clk_set_rate(graph_data->clk_plla_out0, plla_out0_rate);
+ if (err) {
+ dev_err(rtd->card->dev,
+ "Can't set plla_out0 rate %u, err: %d\n",
+ plla_out0_rate, err);
+ return err;
+ }
+
+ return err;
+}
+
+static int tegra_audio_graph_hw_params(struct snd_pcm_substream *substream,
+ struct snd_pcm_hw_params *params)
+{
+ struct snd_soc_pcm_runtime *rtd = asoc_substream_to_rtd(substream);
+ struct snd_soc_dai *cpu_dai = asoc_rtd_to_cpu(rtd, 0);
+ int err;
+
+ /*
+ * This gets called for each DAI link (FE or BE) when DPCM is used.
+ * We may not want to update PLLA rate for each call. So PLLA update
+ * must be restricted to external I/O links (I2S, DMIC or DSPK) since
+ * they actually depend on it. I/O modules update their clocks in
+ * hw_param() of their respective component driver and PLLA rate
+ * update here helps them to derive appropriate rates.
+ *
+ * TODO: When more HW accelerators get added (like sample rate
+ * converter, volume gain controller etc., which don't really
+ * depend on PLLA) we need a better way to filter here.
+ */
+ if (cpu_dai->driver->ops && rtd->dai_link->no_pcm) {
+ err = tegra_audio_graph_update_pll(substream, params);
+ if (err)
+ return err;
+ }
+
+ return asoc_simple_hw_params(substream, params);
+}
+
+static const struct snd_soc_ops tegra_audio_graph_ops = {
+ .startup = asoc_simple_startup,
+ .shutdown = asoc_simple_shutdown,
+ .hw_params = tegra_audio_graph_hw_params,
+};
+
+static int tegra_audio_graph_card_probe(struct snd_soc_card *card)
+{
+ struct asoc_simple_priv *priv = snd_soc_card_get_drvdata(card);
+ struct tegra_audio_graph_data *graph_data =
+ (struct tegra_audio_graph_data *)priv->data;
+
+ graph_data->clk_plla = devm_clk_get(card->dev, "pll_a");
+ if (IS_ERR(graph_data->clk_plla)) {
+ dev_err(card->dev, "Can't retrieve clk pll_a\n");
+ return PTR_ERR(graph_data->clk_plla);
+ }
+
+ graph_data->clk_plla_out0 = devm_clk_get(card->dev, "plla_out0");
+ if (IS_ERR(graph_data->clk_plla_out0)) {
+ dev_err(card->dev, "Can't retrieve clk plla_out0\n");
+ return PTR_ERR(graph_data->clk_plla_out0);
+ }
+
+ return graph_card_probe(card);
+}
+
+static int tegra_audio_graph_probe(struct platform_device *pdev)
+{
+ struct asoc_simple_priv *priv;
+ struct device *dev = &pdev->dev;
+ struct snd_soc_card *card;
+ struct link_info li;
+ int err;
+
+ /* Allocate the private data and the DAI link array */
+ priv = devm_kzalloc(dev, sizeof(*priv), GFP_KERNEL);
+ if (!priv)
+ return -ENOMEM;
+
+ priv->data = (struct tegra_audio_graph_data *)
+ devm_kzalloc(dev, sizeof(*priv->data), GFP_KERNEL);
+ if (!priv->data)
+ return -ENOMEM;
+
+ card = simple_priv_to_card(priv);
+
+ card->owner = THIS_MODULE;
+ card->dev = dev;
+ card->component_chaining = true;
+ card->probe = tegra_audio_graph_card_probe;
+
+ priv->ops = &tegra_audio_graph_ops;
+ priv->force_dpcm = 1;
+
+ memset(&li, 0, sizeof(li));
+ graph_get_dais_count(priv, &li);
+ if (!li.link || !li.dais)
+ return -EINVAL;
+
+ err = asoc_simple_init_priv(priv, &li);
+ if (err < 0)
+ return err;
+
+ err = graph_parse_of(priv);
+ if (err < 0) {
+ if (err != -EPROBE_DEFER)
+ dev_err(dev, "Parse error %d\n", err);
+ goto cleanup;
+ }
+
+ snd_soc_card_set_drvdata(card, priv);
+
+ asoc_simple_debug_info(priv);
+
+ err = devm_snd_soc_register_card(dev, card);
+ if (err < 0)
+ goto cleanup;
+
+ return 0;
+
+cleanup:
+ asoc_simple_clean_reference(card);
+
+ return err;
+}
+
+static const struct tegra_audio_chip_data tegra210_data = {
+ /* PLLA */
+ .plla_rates[x8_RATE] = 368640000,
+ .plla_rates[x11_RATE] = 338688000,
+ /* PLLA_OUT0 */
+ .plla_out0_rates[x8_RATE] = 49152000,
+ .plla_out0_rates[x11_RATE] = 45158400,
+};
+
+static const struct tegra_audio_chip_data tegra186_data = {
+ /* PLLA */
+ .plla_rates[x8_RATE] = 245760000,
+ .plla_rates[x11_RATE] = 270950400,
+ /* PLLA_OUT0 */
+ .plla_out0_rates[x8_RATE] = 49152000,
+ .plla_out0_rates[x11_RATE] = 45158400,
+};
+
+static const struct of_device_id graph_of_tegra_match[] = {
+ { .compatible = "nvidia,tegra210-audio-graph-card",
+ .data = &tegra210_data },
+ { .compatible = "nvidia,tegra186-audio-graph-card",
+ .data = &tegra186_data },
+ {},
+};
+MODULE_DEVICE_TABLE(of, graph_of_tegra_match);
+
+static struct platform_driver tegra_audio_graph_card = {
+ .driver = {
+ .name = "tegra-audio-graph-card",
+ .pm = &snd_soc_pm_ops,
+ .of_match_table = graph_of_tegra_match,
+ },
+ .probe = tegra_audio_graph_probe,
+};
+module_platform_driver(tegra_audio_graph_card);
+
+MODULE_LICENSE("GPL v2");
+MODULE_DESCRIPTION("ASoC Tegra Audio Graph Sound Card");
+MODULE_AUTHOR("Sameer Pujar <spujar at nvidia.com>");
--
2.7.4
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