ASoC: cs42l42: Add SoundWire support

Merge series from Stefan Binding <sbinding@opensource.cirrus.com>:

The CS42L42 has a SoundWire interface for control and audio. This
chain of patches adds support for this.

Patches #1 .. #5 split out various changes to the existing code that
are needed for adding Soundwire. These are mostly around clocking and
supporting the separate probe and enumeration stages in SoundWire.

Patches #6 .. #8 actually adds the SoundWire handling.

drivers/soundwire/stream.c

@@ -469,7 +469,7 @@ static int sdw_prep_deprep_slave_ports(struct sdw_bus *bus,
 	}
 
 	/* Inform slave about the impending port prepare */
-	sdw_do_port_prep(s_rt, prep_ch, SDW_OPS_PORT_PRE_PREP);
+	sdw_do_port_prep(s_rt, prep_ch, prep ? SDW_OPS_PORT_PRE_PREP : SDW_OPS_PORT_PRE_DEPREP);
 
 	/* Prepare Slave port implementing CP_SM */
 	if (!dpn_prop->simple_ch_prep_sm) {
@@ -501,7 +501,7 @@ static int sdw_prep_deprep_slave_ports(struct sdw_bus *bus,
 	}
 
 	/* Inform slaves about ports prepared */
-	sdw_do_port_prep(s_rt, prep_ch, SDW_OPS_PORT_POST_PREP);
+	sdw_do_port_prep(s_rt, prep_ch, prep ? SDW_OPS_PORT_POST_PREP : SDW_OPS_PORT_POST_DEPREP);
 
 	/* Disable interrupt after Port de-prepare */
 	if (!prep && intr)

include/linux/soundwire/sdw.h

@@ -566,13 +566,15 @@ struct sdw_prepare_ch {
  * enum sdw_port_prep_ops: Prepare operations for Data Port
  *
  * @SDW_OPS_PORT_PRE_PREP: Pre prepare operation for the Port
- * @SDW_OPS_PORT_PREP: Prepare operation for the Port
+ * @SDW_OPS_PORT_PRE_DEPREP: Pre deprepare operation for the Port
  * @SDW_OPS_PORT_POST_PREP: Post prepare operation for the Port
+ * @SDW_OPS_PORT_POST_DEPREP: Post deprepare operation for the Port
  */
 enum sdw_port_prep_ops {
 	SDW_OPS_PORT_PRE_PREP = 0,
-	SDW_OPS_PORT_PREP = 1,
-	SDW_OPS_PORT_POST_PREP = 2,
+	SDW_OPS_PORT_PRE_DEPREP,
+	SDW_OPS_PORT_POST_PREP,
+	SDW_OPS_PORT_POST_DEPREP,
 };
 
 /**

include/sound/cs42l42.h

@@ -34,6 +34,7 @@
 #define CS42L42_PAGE_24		0x2400
 #define CS42L42_PAGE_25		0x2500
 #define CS42L42_PAGE_26		0x2600
+#define CS42L42_PAGE_27		0x2700
 #define CS42L42_PAGE_28		0x2800
 #define CS42L42_PAGE_29		0x2900
 #define CS42L42_PAGE_2A		0x2A00
@@ -720,6 +721,10 @@
 
 #define CS42L42_SRC_SDOUT_FS		(CS42L42_PAGE_26 + 0x09)
 
+/* Page 0x27 DMA */
+#define CS42L42_SOFT_RESET_REBOOT	(CS42L42_PAGE_27 + 0x01)
+#define CS42L42_SFT_RST_REBOOT_MASK	BIT(1)
+
 /* Page 0x28 S/PDIF Registers */
 #define CS42L42_SPDIF_CTL1		(CS42L42_PAGE_28 + 0x01)
 #define CS42L42_SPDIF_CTL2		(CS42L42_PAGE_28 + 0x02)

sound/soc/codecs/Kconfig

@@ -69,6 +69,7 @@ config SND_SOC_ALL_CODECS
 	imply SND_SOC_CS35L45_I2C
 	imply SND_SOC_CS35L45_SPI
 	imply SND_SOC_CS42L42
+	imply SND_SOC_CS42L42_SDW
 	imply SND_SOC_CS42L51_I2C
 	imply SND_SOC_CS42L52
 	imply SND_SOC_CS42L56
@@ -722,6 +723,13 @@ config SND_SOC_CS42L42
 	select REGMAP_I2C
 	select SND_SOC_CS42L42_CORE
 
+config SND_SOC_CS42L42_SDW
+	tristate "Cirrus Logic CS42L42 CODEC on Soundwire"
+	depends on SOUNDWIRE
+	select SND_SOC_CS42L42_CORE
+	help
+	  Enable support for Cirrus Logic CS42L42 codec with Soundwire control
+
 config SND_SOC_CS42L51
 	tristate
 

sound/soc/codecs/Makefile

@@ -69,6 +69,7 @@ snd-soc-cs35l45-spi-objs := cs35l45-spi.o
 snd-soc-cs35l45-i2c-objs := cs35l45-i2c.o
 snd-soc-cs42l42-objs := cs42l42.o
 snd-soc-cs42l42-i2c-objs := cs42l42-i2c.o
+snd-soc-cs42l42-sdw-objs := cs42l42-sdw.o
 snd-soc-cs42l51-objs := cs42l51.o
 snd-soc-cs42l51-i2c-objs := cs42l51-i2c.o
 snd-soc-cs42l52-objs := cs42l52.o
@@ -434,6 +435,7 @@ obj-$(CONFIG_SND_SOC_CS35L45_SPI)	+= snd-soc-cs35l45-spi.o
 obj-$(CONFIG_SND_SOC_CS35L45_I2C)	+= snd-soc-cs35l45-i2c.o
 obj-$(CONFIG_SND_SOC_CS42L42_CORE)	+= snd-soc-cs42l42.o
 obj-$(CONFIG_SND_SOC_CS42L42)	+= snd-soc-cs42l42-i2c.o
+obj-$(CONFIG_SND_SOC_CS42L42_SDW)	+= snd-soc-cs42l42-sdw.o
 obj-$(CONFIG_SND_SOC_CS42L51)	+= snd-soc-cs42l51.o
 obj-$(CONFIG_SND_SOC_CS42L51_I2C)	+= snd-soc-cs42l51-i2c.o
 obj-$(CONFIG_SND_SOC_CS42L52)	+= snd-soc-cs42l52.o

sound/soc/codecs/cs42l42.c

@@ -20,6 +20,7 @@
 #include <linux/slab.h>
 #include <linux/acpi.h>
 #include <linux/platform_device.h>
+#include <linux/pm_runtime.h>
 #include <linux/property.h>
 #include <linux/regulator/consumer.h>
 #include <linux/gpio/consumer.h>
@@ -293,6 +294,7 @@ bool cs42l42_readable_register(struct device *dev, unsigned int reg)
 	case CS42L42_SPDIF_SW_CTL1:
 	case CS42L42_SRC_SDIN_FS:
 	case CS42L42_SRC_SDOUT_FS:
+	case CS42L42_SOFT_RESET_REBOOT:
 	case CS42L42_SPDIF_CTL1:
 	case CS42L42_SPDIF_CTL2:
 	case CS42L42_SPDIF_CTL3:
@@ -358,6 +360,7 @@ bool cs42l42_volatile_register(struct device *dev, unsigned int reg)
 	case CS42L42_LOAD_DET_DONE:
 	case CS42L42_DET_STATUS1:
 	case CS42L42_DET_STATUS2:
+	case CS42L42_SOFT_RESET_REBOOT:
 		return true;
 	default:
 		return false;
@@ -523,6 +526,10 @@ static const struct snd_soc_dapm_widget cs42l42_dapm_widgets[] = {
 
 	/* Playback/Capture Requirements */
 	SND_SOC_DAPM_SUPPLY("SCLK", CS42L42_ASP_CLK_CFG, CS42L42_ASP_SCLK_EN_SHIFT, 0, NULL, 0),
+
+	/* Soundwire SRC power control */
+	SND_SOC_DAPM_PGA("DACSRC", CS42L42_PWR_CTL2, CS42L42_DAC_SRC_PDNB_SHIFT, 0, NULL, 0),
+	SND_SOC_DAPM_PGA("ADCSRC", CS42L42_PWR_CTL2, CS42L42_ADC_SRC_PDNB_SHIFT, 0, NULL, 0),
 };
 
 static const struct snd_soc_dapm_route cs42l42_audio_map[] = {
@@ -590,7 +597,6 @@ const struct snd_soc_component_driver cs42l42_soc_component = {
 	.num_dapm_routes	= ARRAY_SIZE(cs42l42_audio_map),
 	.controls		= cs42l42_snd_controls,
 	.num_controls		= ARRAY_SIZE(cs42l42_snd_controls),
-	.idle_bias_on		= 1,
 	.endianness		= 1,
 };
 EXPORT_SYMBOL_NS_GPL(cs42l42_soc_component, SND_SOC_CS42L42_CORE);
@@ -651,11 +657,11 @@ static const struct cs42l42_pll_params pll_ratio_table[] = {
 	{ 24576000, 1, 0x03, 0x40, 0x000000, 0x03, 0x10, 12288000, 128, 1}
 };
 
-static int cs42l42_pll_config(struct snd_soc_component *component, unsigned int clk)
+int cs42l42_pll_config(struct snd_soc_component *component, unsigned int clk,
+		       unsigned int sample_rate)
 {
 	struct cs42l42_private *cs42l42 = snd_soc_component_get_drvdata(component);
 	int i;
-	u32 fsync;
 
 	/* Don't reconfigure if there is an audio stream running */
 	if (cs42l42->stream_use) {
@@ -666,6 +672,10 @@ static int cs42l42_pll_config(struct snd_soc_component *component, unsigned int
 	}
 
 	for (i = 0; i < ARRAY_SIZE(pll_ratio_table); i++) {
+		/* MCLKint must be a multiple of the sample rate */
+		if (pll_ratio_table[i].mclk_int % sample_rate)
+			continue;
+
 		if (pll_ratio_table[i].sclk == clk) {
 			cs42l42->pll_config = i;
 
@@ -677,40 +687,6 @@ static int cs42l42_pll_config(struct snd_soc_component *component, unsigned int
 					(pll_ratio_table[i].mclk_int !=
 					24000000)) <<
 					CS42L42_INTERNAL_FS_SHIFT);
-
-			/* Set up the LRCLK */
-			fsync = clk / cs42l42->srate;
-			if (((fsync * cs42l42->srate) != clk)
-				|| ((fsync % 2) != 0)) {
-				dev_err(component->dev,
-					"Unsupported sclk %d/sample rate %d\n",
-					clk,
-					cs42l42->srate);
-				return -EINVAL;
-			}
-			/* Set the LRCLK period */
-			snd_soc_component_update_bits(component,
-					CS42L42_FSYNC_P_LOWER,
-					CS42L42_FSYNC_PERIOD_MASK,
-					CS42L42_FRAC0_VAL(fsync - 1) <<
-					CS42L42_FSYNC_PERIOD_SHIFT);
-			snd_soc_component_update_bits(component,
-					CS42L42_FSYNC_P_UPPER,
-					CS42L42_FSYNC_PERIOD_MASK,
-					CS42L42_FRAC1_VAL(fsync - 1) <<
-					CS42L42_FSYNC_PERIOD_SHIFT);
-			/* Set the LRCLK to 50% duty cycle */
-			fsync = fsync / 2;
-			snd_soc_component_update_bits(component,
-					CS42L42_FSYNC_PW_LOWER,
-					CS42L42_FSYNC_PULSE_WIDTH_MASK,
-					CS42L42_FRAC0_VAL(fsync - 1) <<
-					CS42L42_FSYNC_PULSE_WIDTH_SHIFT);
-			snd_soc_component_update_bits(component,
-					CS42L42_FSYNC_PW_UPPER,
-					CS42L42_FSYNC_PULSE_WIDTH_MASK,
-					CS42L42_FRAC1_VAL(fsync - 1) <<
-					CS42L42_FSYNC_PULSE_WIDTH_SHIFT);
 			if (pll_ratio_table[i].mclk_src_sel == 0) {
 				/* Pass the clock straight through */
 				snd_soc_component_update_bits(component,
@@ -768,8 +744,9 @@ static int cs42l42_pll_config(struct snd_soc_component *component, unsigned int
 
 	return -EINVAL;
 }
+EXPORT_SYMBOL_NS_GPL(cs42l42_pll_config, SND_SOC_CS42L42_CORE);
 
-static void cs42l42_src_config(struct snd_soc_component *component, unsigned int sample_rate)
+void cs42l42_src_config(struct snd_soc_component *component, unsigned int sample_rate)
 {
 	struct cs42l42_private *cs42l42 = snd_soc_component_get_drvdata(component);
 	unsigned int fs;
@@ -801,6 +778,47 @@ static void cs42l42_src_config(struct snd_soc_component *component, unsigned int
 				      CS42L42_CLK_OASRC_SEL_MASK,
 				      fs << CS42L42_CLK_OASRC_SEL_SHIFT);
 }
+EXPORT_SYMBOL_NS_GPL(cs42l42_src_config, SND_SOC_CS42L42_CORE);
+
+static int cs42l42_asp_config(struct snd_soc_component *component,
+			      unsigned int sclk, unsigned int sample_rate)
+{
+	u32 fsync = sclk / sample_rate;
+
+	/* Set up the LRCLK */
+	if (((fsync * sample_rate) != sclk) || ((fsync % 2) != 0)) {
+		dev_err(component->dev,
+			"Unsupported sclk %d/sample rate %d\n",
+			sclk,
+			sample_rate);
+		return -EINVAL;
+	}
+	/* Set the LRCLK period */
+	snd_soc_component_update_bits(component,
+				      CS42L42_FSYNC_P_LOWER,
+				      CS42L42_FSYNC_PERIOD_MASK,
+				      CS42L42_FRAC0_VAL(fsync - 1) <<
+				      CS42L42_FSYNC_PERIOD_SHIFT);
+	snd_soc_component_update_bits(component,
+				      CS42L42_FSYNC_P_UPPER,
+				      CS42L42_FSYNC_PERIOD_MASK,
+				      CS42L42_FRAC1_VAL(fsync - 1) <<
+				      CS42L42_FSYNC_PERIOD_SHIFT);
+	/* Set the LRCLK to 50% duty cycle */
+	fsync = fsync / 2;
+	snd_soc_component_update_bits(component,
+				      CS42L42_FSYNC_PW_LOWER,
+				      CS42L42_FSYNC_PULSE_WIDTH_MASK,
+				      CS42L42_FRAC0_VAL(fsync - 1) <<
+				      CS42L42_FSYNC_PULSE_WIDTH_SHIFT);
+	snd_soc_component_update_bits(component,
+				      CS42L42_FSYNC_PW_UPPER,
+				      CS42L42_FSYNC_PULSE_WIDTH_MASK,
+				      CS42L42_FRAC1_VAL(fsync - 1) <<
+				      CS42L42_FSYNC_PULSE_WIDTH_SHIFT);
+
+	return 0;
+}
 
 static int cs42l42_set_dai_fmt(struct snd_soc_dai *codec_dai, unsigned int fmt)
 {
@@ -891,13 +909,12 @@ static int cs42l42_pcm_hw_params(struct snd_pcm_substream *substream,
 	struct cs42l42_private *cs42l42 = snd_soc_component_get_drvdata(component);
 	unsigned int channels = params_channels(params);
 	unsigned int width = (params_width(params) / 8) - 1;
+	unsigned int sample_rate = params_rate(params);
 	unsigned int slot_width = 0;
 	unsigned int val = 0;
 	unsigned int bclk;
 	int ret;
 
-	cs42l42->srate = params_rate(params);
-
 	if (cs42l42->bclk_ratio) {
 		/* machine driver has set the BCLK/samp-rate ratio */
 		bclk = cs42l42->bclk_ratio * params_rate(params);
@@ -954,11 +971,15 @@ static int cs42l42_pcm_hw_params(struct snd_pcm_substream *substream,
 		break;
 	}
 
-	ret = cs42l42_pll_config(component, bclk);
+	ret = cs42l42_pll_config(component, bclk, sample_rate);
+	if (ret)
+		return ret;
+
+	ret = cs42l42_asp_config(component, bclk, sample_rate);
 	if (ret)
 		return ret;
 
-	cs42l42_src_config(component, params_rate(params));
+	cs42l42_src_config(component, sample_rate);
 
 	return 0;
 }
@@ -998,7 +1019,7 @@ static int cs42l42_set_bclk_ratio(struct snd_soc_dai *dai,
 	return 0;
 }
 
-static int cs42l42_mute_stream(struct snd_soc_dai *dai, int mute, int stream)
+int cs42l42_mute_stream(struct snd_soc_dai *dai, int mute, int stream)
 {
 	struct snd_soc_component *component = dai->component;
 	struct cs42l42_private *cs42l42 = snd_soc_component_get_drvdata(component);
@@ -1091,6 +1112,7 @@ static int cs42l42_mute_stream(struct snd_soc_dai *dai, int mute, int stream)
 
 	return 0;
 }
+EXPORT_SYMBOL_NS_GPL(cs42l42_mute_stream, SND_SOC_CS42L42_CORE);
 
 #define CS42L42_FORMATS (SNDRV_PCM_FMTBIT_S16_LE |\
 			 SNDRV_PCM_FMTBIT_S24_LE |\
@@ -1633,7 +1655,7 @@ static const struct cs42l42_irq_params irq_params_table[] = {
 		CS42L42_TSRS_PLUG_VAL_MASK}
 };
 
-static irqreturn_t cs42l42_irq_thread(int irq, void *data)
+irqreturn_t cs42l42_irq_thread(int irq, void *data)
 {
 	struct cs42l42_private *cs42l42 = (struct cs42l42_private *)data;
 	unsigned int stickies[12];
@@ -1642,9 +1664,11 @@ static irqreturn_t cs42l42_irq_thread(int irq, void *data)
 	unsigned int current_button_status;
 	unsigned int i;
 
+	pm_runtime_get_sync(cs42l42->dev);
 	mutex_lock(&cs42l42->irq_lock);
 	if (cs42l42->suspended || !cs42l42->init_done) {
 		mutex_unlock(&cs42l42->irq_lock);
+		pm_runtime_put_autosuspend(cs42l42->dev);
 		return IRQ_NONE;
 	}
 
@@ -1747,9 +1771,12 @@ static irqreturn_t cs42l42_irq_thread(int irq, void *data)
 	}
 
 	mutex_unlock(&cs42l42->irq_lock);
+	pm_runtime_mark_last_busy(cs42l42->dev);
+	pm_runtime_put_autosuspend(cs42l42->dev);
 
 	return IRQ_HANDLED;
 }
+EXPORT_SYMBOL_NS_GPL(cs42l42_irq_thread, SND_SOC_CS42L42_CORE);
 
 static void cs42l42_set_interrupt_masks(struct cs42l42_private *cs42l42)
 {
@@ -2125,6 +2152,9 @@ int cs42l42_suspend(struct device *dev)
 	u8 save_regs[ARRAY_SIZE(cs42l42_shutdown_seq)];
 	int i, ret;
 
+	if (!cs42l42->init_done)
+		return 0;
+
 	/*
 	 * Wait for threaded irq handler to be idle and stop it processing
 	 * future interrupts. This ensures a safe disable if the interrupt
@@ -2185,6 +2215,9 @@ int cs42l42_resume(struct device *dev)
 	struct cs42l42_private *cs42l42 = dev_get_drvdata(dev);
 	int ret;
 
+	if (!cs42l42->init_done)
+		return 0;
+
 	/*
 	 * If jack was unplugged and re-plugged during suspend it could
 	 * have changed type but the tip-sense state hasn't changed.
@@ -2369,6 +2402,18 @@ int cs42l42_init(struct cs42l42_private *cs42l42)
 	if (ret != 0)
 		goto err_shutdown;
 
+	/*
+	 * SRC power is linked to ASP power so doesn't work in Soundwire mode.
+	 * Override it and use DAPM to control SRC power for Soundwire.
+	 */
+	if (cs42l42->sdw_peripheral) {
+		regmap_update_bits(cs42l42->regmap, CS42L42_PWR_CTL2,
+				   CS42L42_SRC_PDN_OVERRIDE_MASK |
+				   CS42L42_DAC_SRC_PDNB_MASK |
+				   CS42L42_ADC_SRC_PDNB_MASK,
+				   CS42L42_SRC_PDN_OVERRIDE_MASK);
+	}
+
 	/* Setup headset detection */
 	cs42l42_setup_hs_type_detect(cs42l42);
 

sound/soc/codecs/cs42l42.h

@@ -18,6 +18,7 @@
 #include <linux/mutex.h>
 #include <linux/regmap.h>
 #include <linux/regulator/consumer.h>
+#include <linux/soundwire/sdw.h>
 #include <sound/jack.h>
 #include <sound/cs42l42.h>
 #include <sound/soc-component.h>
@@ -30,13 +31,14 @@ struct  cs42l42_private {
 	struct gpio_desc *reset_gpio;
 	struct completion pdn_done;
 	struct snd_soc_jack *jack;
+	struct sdw_slave *sdw_peripheral;
 	struct mutex irq_lock;
 	int devid;
 	int irq;
 	int pll_config;
 	u32 sclk;
+	u32 sample_rate;
 	u32 bclk_ratio;
-	u32 srate;
 	u8 plug_state;
 	u8 hs_type;
 	u8 ts_inv;
@@ -62,6 +64,11 @@ extern struct snd_soc_dai_driver cs42l42_dai;
 bool cs42l42_readable_register(struct device *dev, unsigned int reg);
 bool cs42l42_volatile_register(struct device *dev, unsigned int reg);
 
+int cs42l42_pll_config(struct snd_soc_component *component,
+		       unsigned int clk, unsigned int sample_rate);
+void cs42l42_src_config(struct snd_soc_component *component, unsigned int sample_rate);
+int cs42l42_mute_stream(struct snd_soc_dai *dai, int mute, int stream);
+irqreturn_t cs42l42_irq_thread(int irq, void *data);
 int cs42l42_suspend(struct device *dev);
 int cs42l42_resume(struct device *dev);
 void cs42l42_resume_restore(struct device *dev);