ASoC: Intel: boards: sof-wm8804: support for Hifiberry Digiplus boards

Add a new machine driver to interface with WM8804. The code is based
on settings found in sound/soc/bcm/hifiberry-digi.c in the Raspberry
PI tree.

Tested on Up2 with Digi+ IO (capture+playback) and Digi+ PRO (playback
with two local oscillators supported). The codec is clock master in
both cases.

Capture support has known clocking restrictions: the transmitter needs
to be active for the clock recovery, the "Tx Source" mixer set to
"S/PDIF RX". Playback will only work while capture is active.

When Capture is not desired, or when there is no RX connector, the "Tx
Source" mixer should be set to "AIF"
Signed-off-by: Pierre-Louis Bossart <pierre-louis.bossart@linux.intel.com>
Reviewed-by: Ranjani Sridharan <ranjani.sridharan@linux.intel.com>
Link: https://lore.kernel.org/r/20200501151625.17820-1-pierre-louis.bossart@linux.intel.comSigned-off-by: Mark Brown <broonie@kernel.org>

sound/soc/intel/boards/Kconfig

@@ -324,6 +324,21 @@ config SND_SOC_INTEL_BXT_RT298_MACH
 
 endif ## SND_SOC_INTEL_APL
 
+if SND_SOC_SOF_APOLLOLAKE
+
+config SND_SOC_INTEL_SOF_WM8804_MACH
+	tristate "SOF with Wolfson/Cirrus WM8804 codec"
+	depends on I2C && ACPI
+	depends on MFD_INTEL_LPSS || COMPILE_TEST
+	select SND_SOC_WM8804_I2C
+	help
+	  This adds support for ASoC machine driver for Intel platforms
+	  with the Wolfson/Cirrus WM8804 I2S audio codec.
+	  Say Y or m if you have such a device. This is a recommended option.
+	  If unsure select "N".
+
+endif ## SND_SOC_SOF_APOLLOLAKE
+
 if SND_SOC_INTEL_KBL
 
 config SND_SOC_INTEL_KBL_RT5663_MAX98927_MACH

sound/soc/intel/boards/Makefile

@@ -8,6 +8,7 @@ snd-soc-sst-broadwell-objs := broadwell.o
 snd-soc-sst-bxt-da7219_max98357a-objs := bxt_da7219_max98357a.o hda_dsp_common.o
 snd-soc-sst-bxt-rt298-objs := bxt_rt298.o hda_dsp_common.o
 snd-soc-sst-sof-pcm512x-objs := sof_pcm512x.o hda_dsp_common.o
+snd-soc-sst-sof-wm8804-objs := sof_wm8804.o
 snd-soc-sst-glk-rt5682_max98357a-objs := glk_rt5682_max98357a.o hda_dsp_common.o
 snd-soc-sst-bytcr-rt5640-objs := bytcr_rt5640.o
 snd-soc-sst-bytcr-rt5651-objs := bytcr_rt5651.o
@@ -44,6 +45,7 @@ obj-$(CONFIG_SND_SOC_INTEL_BYT_MAX98090_MACH) += snd-soc-sst-byt-max98090-mach.o
 obj-$(CONFIG_SND_SOC_INTEL_BXT_DA7219_MAX98357A_COMMON) += snd-soc-sst-bxt-da7219_max98357a.o
 obj-$(CONFIG_SND_SOC_INTEL_BXT_RT298_MACH) += snd-soc-sst-bxt-rt298.o
 obj-$(CONFIG_SND_SOC_INTEL_SOF_PCM512x_MACH) += snd-soc-sst-sof-pcm512x.o
+obj-$(CONFIG_SND_SOC_INTEL_SOF_WM8804_MACH) += snd-soc-sst-sof-wm8804.o
 obj-$(CONFIG_SND_SOC_INTEL_GLK_RT5682_MAX98357A_MACH) += snd-soc-sst-glk-rt5682_max98357a.o
 obj-$(CONFIG_SND_SOC_INTEL_BROADWELL_MACH) += snd-soc-sst-broadwell.o
 obj-$(CONFIG_SND_SOC_INTEL_BDW_RT5650_MACH) += snd-soc-sst-bdw-rt5650-mach.o

sound/soc/intel/boards/sof_wm8804.c

+// SPDX-License-Identifier: GPL-2.0-only
+// Copyright (c) 2018-2020, Intel Corporation
+//
+// sof-wm8804.c - ASoC machine driver for Up and Up2 board
+// based on WM8804/Hifiberry Digi+
+
+
+#include <linux/acpi.h>
+#include <linux/dmi.h>
+#include <linux/gpio/consumer.h>
+#include <linux/gpio/machine.h>
+#include <linux/module.h>
+#include <linux/platform_device.h>
+#include <linux/slab.h>
+#include <sound/pcm.h>
+#include <sound/pcm_params.h>
+#include <sound/soc.h>
+#include <sound/soc-acpi.h>
+#include "../../codecs/wm8804.h"
+
+struct sof_card_private {
+	struct gpio_desc *gpio_44;
+	struct gpio_desc *gpio_48;
+	int sample_rate;
+};
+
+#define SOF_WM8804_UP2_QUIRK			BIT(0)
+
+static unsigned long sof_wm8804_quirk;
+
+static int sof_wm8804_quirk_cb(const struct dmi_system_id *id)
+{
+	sof_wm8804_quirk = (unsigned long)id->driver_data;
+	return 1;
+}
+
+static const struct dmi_system_id sof_wm8804_quirk_table[] = {
+	{
+		.callback = sof_wm8804_quirk_cb,
+		.matches = {
+			DMI_MATCH(DMI_SYS_VENDOR, "AAEON"),
+			DMI_MATCH(DMI_PRODUCT_NAME, "UP-APL01"),
+		},
+		.driver_data = (void *)SOF_WM8804_UP2_QUIRK,
+	},
+	{}
+};
+
+static int sof_wm8804_hw_params(struct snd_pcm_substream *substream,
+				struct snd_pcm_hw_params *params)
+{
+	struct snd_soc_pcm_runtime *rtd = substream->private_data;
+	struct sof_card_private *ctx = snd_soc_card_get_drvdata(rtd->card);
+	struct snd_soc_dai *codec_dai = asoc_rtd_to_codec(rtd, 0);
+	struct snd_soc_component *codec = codec_dai->component;
+	const int sysclk = 27000000; /* This is fixed on this board */
+	int samplerate;
+	long mclk_freq;
+	int mclk_div;
+	int sampling_freq;
+	bool clk_44;
+	int ret;
+
+	samplerate = params_rate(params);
+	if (samplerate == ctx->sample_rate)
+		return 0;
+
+	ctx->sample_rate = 0;
+
+	if (samplerate <= 96000) {
+		mclk_freq = samplerate * 256;
+		mclk_div = WM8804_MCLKDIV_256FS;
+	} else {
+		mclk_freq = samplerate * 128;
+		mclk_div = WM8804_MCLKDIV_128FS;
+	}
+
+	switch (samplerate) {
+	case 32000:
+		sampling_freq = 0x03;
+		break;
+	case 44100:
+		sampling_freq = 0x00;
+		break;
+	case 48000:
+		sampling_freq = 0x02;
+		break;
+	case 88200:
+		sampling_freq = 0x08;
+		break;
+	case 96000:
+		sampling_freq = 0x0a;
+		break;
+	case 176400:
+		sampling_freq = 0x0c;
+		break;
+	case 192000:
+		sampling_freq = 0x0e;
+		break;
+	default:
+		dev_err(rtd->card->dev,
+			"unsupported samplerate %d\n", samplerate);
+		return -EINVAL;
+	}
+
+	if (samplerate % 16000)
+		clk_44 = true; /* use 44.1 kHz root frequency */
+	else
+		clk_44 = false;
+
+	if (!(IS_ERR_OR_NULL(ctx->gpio_44) ||
+	      IS_ERR_OR_NULL(ctx->gpio_48))) {
+		/*
+		 * ensure both GPIOs are LOW first, then drive the
+		 * relevant one to HIGH
+		 */
+		if (clk_44) {
+			gpiod_set_value_cansleep(ctx->gpio_48, !clk_44);
+			gpiod_set_value_cansleep(ctx->gpio_44, clk_44);
+		} else {
+			gpiod_set_value_cansleep(ctx->gpio_44, clk_44);
+			gpiod_set_value_cansleep(ctx->gpio_48, !clk_44);
+		}
+	}
+
+	snd_soc_dai_set_clkdiv(codec_dai, WM8804_MCLK_DIV, mclk_div);
+	snd_soc_dai_set_pll(codec_dai, 0, 0, sysclk, mclk_freq);
+
+	ret = snd_soc_dai_set_sysclk(codec_dai, WM8804_TX_CLKSRC_PLL,
+				     sysclk, SND_SOC_CLOCK_OUT);
+	if (ret < 0) {
+		dev_err(rtd->card->dev,
+			"Failed to set WM8804 SYSCLK: %d\n", ret);
+		return ret;
+	}
+
+	/* set sampling frequency status bits */
+	snd_soc_component_update_bits(codec, WM8804_SPDTX4, 0x0f,
+				      sampling_freq);
+
+	ctx->sample_rate = samplerate;
+
+	return 0;
+}
+
+/* machine stream operations */
+static struct snd_soc_ops sof_wm8804_ops = {
+	.hw_params = sof_wm8804_hw_params,
+};
+
+SND_SOC_DAILINK_DEF(ssp5_pin,
+	DAILINK_COMP_ARRAY(COMP_CPU("SSP5 Pin")));
+
+SND_SOC_DAILINK_DEF(ssp5_codec,
+	DAILINK_COMP_ARRAY(COMP_CODEC("i2c-1AEC8804:00", "wm8804-spdif")));
+
+SND_SOC_DAILINK_DEF(platform,
+	DAILINK_COMP_ARRAY(COMP_PLATFORM("0000:00:0e.0")));
+
+static struct snd_soc_dai_link dailink[] = {
+	/* back ends */
+	{
+		.name = "SSP5-Codec",
+		.id = 0,
+		.no_pcm = 1,
+		.nonatomic = true,
+		.dpcm_playback = 1,
+		.dpcm_capture = 1,
+		.ops = &sof_wm8804_ops,
+		SND_SOC_DAILINK_REG(ssp5_pin, ssp5_codec, platform),
+	},
+};
+
+/* SoC card */
+static struct snd_soc_card sof_wm8804_card = {
+	.name = "wm8804", /* sof- prefix added automatically */
+	.owner = THIS_MODULE,
+	.dai_link = dailink,
+	.num_links = ARRAY_SIZE(dailink),
+};
+
+ /* i2c-<HID>:00 with HID being 8 chars */
+static char codec_name[SND_ACPI_I2C_ID_LEN];
+
+/*
+ * to control the HifiBerry Digi+ PRO, it's required to toggle GPIO to
+ * select the clock source. On the Up2 board, this means
+ * Pin29/BCM5/Linux GPIO 430 and Pin 31/BCM6/ Linux GPIO 404.
+ *
+ * Using the ACPI device name is not very nice, but since we only use
+ * the value for the Up2 board there is no risk of conflict with other
+ * platforms.
+ */
+
+static struct gpiod_lookup_table up2_gpios_table = {
+	/* .dev_id is set during probe */
+	.table = {
+		GPIO_LOOKUP("INT3452:01", 73, "BCM-GPIO5", GPIO_ACTIVE_HIGH),
+		GPIO_LOOKUP("INT3452:01", 74, "BCM-GPIO6", GPIO_ACTIVE_HIGH),
+		{ },
+	},
+};
+
+static int sof_wm8804_probe(struct platform_device *pdev)
+{
+	struct snd_soc_card *card;
+	struct snd_soc_acpi_mach *mach;
+	struct sof_card_private *ctx;
+	struct acpi_device *adev;
+	int dai_index = 0;
+	int ret;
+	int i;
+
+	ctx = devm_kzalloc(&pdev->dev, sizeof(*ctx), GFP_KERNEL);
+	if (!ctx)
+		return -ENOMEM;
+
+	mach = pdev->dev.platform_data;
+	card = &sof_wm8804_card;
+	card->dev = &pdev->dev;
+
+	dmi_check_system(sof_wm8804_quirk_table);
+
+	if (sof_wm8804_quirk & SOF_WM8804_UP2_QUIRK) {
+		up2_gpios_table.dev_id = dev_name(&pdev->dev);
+		gpiod_add_lookup_table(&up2_gpios_table);
+
+		/*
+		 * The gpios are required for specific boards with
+		 * local oscillators, and optional in other cases.
+		 * Since we can't identify when they are needed, use
+		 * the GPIO as non-optional
+		 */
+
+		ctx->gpio_44 = devm_gpiod_get(&pdev->dev, "BCM-GPIO5",
+					      GPIOD_OUT_LOW);
+		if (IS_ERR(ctx->gpio_44)) {
+			ret = PTR_ERR(ctx->gpio_44);
+			dev_err(&pdev->dev,
+				"could not get BCM-GPIO5: %d\n",
+				ret);
+			return ret;
+		}
+
+		ctx->gpio_48 = devm_gpiod_get(&pdev->dev, "BCM-GPIO6",
+					      GPIOD_OUT_LOW);
+		if (IS_ERR(ctx->gpio_48)) {
+			ret = PTR_ERR(ctx->gpio_48);
+			dev_err(&pdev->dev,
+				"could not get BCM-GPIO6: %d\n",
+				ret);
+			return ret;
+		}
+	}
+
+	/* fix index of codec dai */
+	for (i = 0; i < ARRAY_SIZE(dailink); i++) {
+		if (!strcmp(dailink[i].codecs->name, "i2c-1AEC8804:00")) {
+			dai_index = i;
+			break;
+		}
+	}
+
+	/* fixup codec name based on HID */
+	adev = acpi_dev_get_first_match_dev(mach->id, NULL, -1);
+	if (adev) {
+		snprintf(codec_name, sizeof(codec_name),
+			 "%s%s", "i2c-", acpi_dev_name(adev));
+		put_device(&adev->dev);
+		dailink[dai_index].codecs->name = codec_name;
+	}
+
+	snd_soc_card_set_drvdata(card, ctx);
+
+	return devm_snd_soc_register_card(&pdev->dev, card);
+}
+
+static int sof_wm8804_remove(struct platform_device *pdev)
+{
+	if (sof_wm8804_quirk & SOF_WM8804_UP2_QUIRK)
+		gpiod_remove_lookup_table(&up2_gpios_table);
+	return 0;
+}
+
+static struct platform_driver sof_wm8804_driver = {
+	.driver = {
+		.name = "sof-wm8804",
+		.pm = &snd_soc_pm_ops,
+	},
+	.probe = sof_wm8804_probe,
+	.remove = sof_wm8804_remove,
+};
+module_platform_driver(sof_wm8804_driver);
+
+MODULE_DESCRIPTION("ASoC Intel(R) SOF + WM8804 Machine driver");
+MODULE_AUTHOR("Pierre-Louis Bossart");
+MODULE_LICENSE("GPL v2");
+MODULE_ALIAS("platform:sof-wm8804");