diff mbox series

[v2,1/3] ASoC: Add support for Loongson I2S controller

Message ID 20230612085318.3039485-1-mengyingkun@loongson.cn
State New
Headers show
Series [v2,1/3] ASoC: Add support for Loongson I2S controller | expand

Commit Message

YingKun Meng June 12, 2023, 8:53 a.m. UTC
From: Yingkun Meng <mengyingkun@loongson.cn>

Loongson I2S controller is found on 7axxx/2kxxx chips from loongson,
it is a PCI device with two private DMA controllers, one for playback,
the other for capture.

The driver supports the use of DTS or ACPI to describe device resources.

Signed-off-by: Yingkun Meng <mengyingkun@loongson.cn>
Reported-by: kernel test robot <lkp@intel.com>
Closes: https://lore.kernel.org/oe-kbuild-all/202306060223.9hdivLrx-lkp@intel.com/
Closes: https://lore.kernel.org/oe-kbuild-all/202306060320.Sphw0ihy-lkp@intel.com/
---
 sound/soc/Kconfig                     |   1 +
 sound/soc/Makefile                    |   1 +
 sound/soc/loongson/Kconfig            |  16 +
 sound/soc/loongson/Makefile           |   4 +
 sound/soc/loongson/loongson_i2s.c     | 213 +++++++++++
 sound/soc/loongson/loongson_i2s.h     |  70 ++++
 sound/soc/loongson/loongson_i2s_pci.c | 500 ++++++++++++++++++++++++++
 7 files changed, 805 insertions(+)
 create mode 100644 sound/soc/loongson/Kconfig
 create mode 100644 sound/soc/loongson/Makefile
 create mode 100644 sound/soc/loongson/loongson_i2s.c
 create mode 100644 sound/soc/loongson/loongson_i2s.h
 create mode 100644 sound/soc/loongson/loongson_i2s_pci.c

Comments

YingKun Meng June 14, 2023, 9:05 a.m. UTC | #1
On 2023/6/13 02:52, Mark Brown wrote:
> On Mon, Jun 12, 2023 at 04:53:18PM +0800, YingKun Meng wrote:
>
>> Loongson I2S controller is found on 7axxx/2kxxx chips from loongson,
>> it is a PCI device with two private DMA controllers, one for playback,
>> the other for capture.
>>
>> The driver supports the use of DTS or ACPI to describe device resources.
>> Reported-by: kernel test robot <lkp@intel.com>
>> Closes: https://lore.kernel.org/oe-kbuild-all/202306060223.9hdivLrx-lkp@intel.com/
>> Closes: https://lore.kernel.org/oe-kbuild-all/202306060320.Sphw0ihy-lkp@intel.com/
> These don't really make sense for a new driver.
>

OK, removed in new version.

>> @@ -0,0 +1,213 @@
>> +// SPDX-License-Identifier: GPL-2.0
>> +/*
>> + * Loongson-2K I2S master mode driver
>> + *
>> + * Copyright (C) 2022 Loongson Technology Corporation Limited
>> + */
> Please make the entire comment a C++ one so things look more
> intentional.  You might also want to update the copyright year if there
> was any substantial work on the driver recently.

OK.

>> +		/* Enable master mode */
>> +		regmap_update_bits(i2s->regmap, LS_I2S_CTRL, I2S_CTRL_MASTER,
>> +				   I2S_CTRL_MASTER);
>> +		if (i2s->rev_id == 1) {
>> +			ret = regmap_read_poll_timeout_atomic(i2s->regmap,
>> +						LS_I2S_CTRL, val,
>> +						val & I2S_CTRL_CLK_READY,
>> +						10, 2000);
>> +			if (ret < 0)
>> +				dev_warn(dai->dev, "wait BCLK ready timeout\n");
>> +		}
> Ideally you'd have a set_dai_fmt() operation and support both clock
> provider and consumer mode.

Got it, add .set_fmt callback for DAI ops in new version.

>> +	if (i2s->rev_id == 0) {
>> +	} else if (i2s->rev_id == 1) {
>> +	} else
>> +		dev_err(i2s->dev, "I2S revision invalid\n");
>> +
> This looks like a switch statement.


OK, replaced with a switch statement in new version.

>
>> +static int loongson_i2s_set_dai_sysclk(struct snd_soc_dai *dai, int clk_id,
>> +				       unsigned int freq, int dir)
>> +{
>> +	struct loongson_i2s *i2s = snd_soc_dai_get_drvdata(dai);
>> +
>> +	i2s->sysclk = freq;
>> +
>> +	return 0;
>> +}
> Should this be integrated with the clock API rather than just using the
> ASoC specific stuff - where does this sysclk come from?  I do note that
> the PCI driver appears to have a fixed clock...
>
You are right, PCI bus has a fixed clock.

On loongson 7A2000/2K2000 chips, the I2S controller has PCI configuration
address space, IO address space, and memory address space, it works as
a PCI device, but it's not a standard PCI device.

Its clock signal comes from the APB bus or AIX bus, not from PCI bus.
Currently, there is no good support from clock subsystem, the frequency of
the I2S controller's driver clock is a fixed value.

>> +void loongson_i2s_init(struct loongson_i2s *i2s)
>> +{
>> +	if (i2s->rev_id == 1) {
>> +		regmap_write(i2s->regmap, LS_I2S_CTRL, I2S_CTRL_RESET);
>> +		udelay(200);
>> +	}
>> +}
> What's this for?  I'd expect initialising the hardware to be handled
> internally within the driver but this is semi-exported?


On 2K1000LA chip, the i2s controller is a platform device, it's supported
by another driver. My original purpose was to export an API to initializing
hardware.
It's OK to move this to specific I2S driver.

>> diff --git a/sound/soc/loongson/loongson_i2s_pci.c b/sound/soc/loongson/loongson_i2s_pci.c
>> new file mode 100644
>> index 000000000000..f09713b560e9
>> --- /dev/null
>> +++ b/sound/soc/loongson/loongson_i2s_pci.c
>> @@ -0,0 +1,500 @@
> Please split the PCI driver into a separate patch to keep the individual
> reviews smaller.


OK, the driver split into PCI driver and DMA driver in new version.

>> +static int loongson_pcm_trigger(struct snd_soc_component *component,
>> +				struct snd_pcm_substream *substream, int cmd)
>> +{
>> +	switch (cmd) {
>> +	default:
>> +		ret = -EINVAL;
>> +	}
> Missing break; here.


Fixed. Return directly.

>
>> +	/* initialize dma descriptor array */
>> +	mem_addr = runtime->dma_addr;
>> +	order_addr = prtd->dma_desc_arr_phy;
>> +	for (i = 0; i < num_periods; i++) {
>> +		desc = &prtd->dma_desc_arr[i];
> We didn't validate that the number of periods fits in the array.
>

Fixed. Check the number of periods before initializing the descriptor array.

>> +	if (num_periods > 0) {
>> +		desc = &prtd->dma_desc_arr[num_periods - 1];
>> +		desc->order = lower_32_bits(prtd->dma_desc_arr_phy | BIT(0));
>> +		desc->order_hi = upper_32_bits(prtd->dma_desc_arr_phy);
>> +	}
> This is always true, right?


Yes, remove the condition check.

>> +       ret = request_irq(dma_data->irq, loongson_pcm_dma_irq,
>> +                         IRQF_TRIGGER_HIGH, LS_I2S_DRVNAME, substream);
> Does it really make sense to request and free the interrupt when the
> stream is running?  It's generally better to just request the interrupt
> once during probe(), that way we know we've got all the resources we
> need.  If we do need to allocate/free all the time a comment explaining
> why would be good so people don't go trying to fix this.

No, we can request the interrupt just once.

As one DMA controller controls the transmission of audio data in one direction
(playback or capture), it is associated with a substream.
The operation requesting interrupt is placed in .pcm_construct callback of
snd_soc_component_driver in new version.

>> +	ret = pci_request_region(pdev, BAR_NUM, LS_I2S_DRVNAME);
>> +	if (ret) {
>> +		dev_err(&pdev->dev, "request regions failed %d\n", ret);
>> +		return ret;
>> +	}
> pcim_iomap_regions()?  At the minute you'll free the region before devm
> frees the regmap which is probably harmless but not ideal.


OK, replaced in new version.
diff mbox series

Patch

diff --git a/sound/soc/Kconfig b/sound/soc/Kconfig
index 4b6e5a802880..bfa9622e1ab1 100644
--- a/sound/soc/Kconfig
+++ b/sound/soc/Kconfig
@@ -79,6 +79,7 @@  source "sound/soc/google/Kconfig"
 source "sound/soc/hisilicon/Kconfig"
 source "sound/soc/jz4740/Kconfig"
 source "sound/soc/kirkwood/Kconfig"
+source "sound/soc/loongson/Kconfig"
 source "sound/soc/img/Kconfig"
 source "sound/soc/intel/Kconfig"
 source "sound/soc/mediatek/Kconfig"
diff --git a/sound/soc/Makefile b/sound/soc/Makefile
index 9d9b228e4508..8376fdb217ed 100644
--- a/sound/soc/Makefile
+++ b/sound/soc/Makefile
@@ -46,6 +46,7 @@  obj-$(CONFIG_SND_SOC)	+= fsl/
 obj-$(CONFIG_SND_SOC)	+= google/
 obj-$(CONFIG_SND_SOC)	+= hisilicon/
 obj-$(CONFIG_SND_SOC)	+= jz4740/
+obj-$(CONFIG_SND_SOC)	+= loongson/
 obj-$(CONFIG_SND_SOC)	+= img/
 obj-$(CONFIG_SND_SOC)	+= intel/
 obj-$(CONFIG_SND_SOC)	+= mediatek/
diff --git a/sound/soc/loongson/Kconfig b/sound/soc/loongson/Kconfig
new file mode 100644
index 000000000000..4478ac91e402
--- /dev/null
+++ b/sound/soc/loongson/Kconfig
@@ -0,0 +1,16 @@ 
+# SPDX-License-Identifier: GPL-2.0
+menu "SoC Audio for Loongson CPUs"
+	depends on LOONGARCH || COMPILE_TEST
+
+config SND_SOC_LOONGSON_I2S_PCI
+	tristate "Loongson I2S-PCI Device Driver"
+	select REGMAP_MMIO
+	depends on PCI
+	help
+	  Say Y or M if you want to add support for I2S driver for
+	  Loongson I2S controller.
+
+	  The controller is found in loongson bridge chips or SoCs,
+	  and work as a PCI device.
+
+endmenu
diff --git a/sound/soc/loongson/Makefile b/sound/soc/loongson/Makefile
new file mode 100644
index 000000000000..cfd0de1b1b22
--- /dev/null
+++ b/sound/soc/loongson/Makefile
@@ -0,0 +1,4 @@ 
+# SPDX-License-Identifier: GPL-2.0
+#Platform Support
+snd-soc-loongson-i2s-pci-objs := loongson_i2s_pci.o loongson_i2s.o
+obj-$(CONFIG_SND_SOC_LOONGSON_I2S_PCI) += snd-soc-loongson-i2s-pci.o
diff --git a/sound/soc/loongson/loongson_i2s.c b/sound/soc/loongson/loongson_i2s.c
new file mode 100644
index 000000000000..31e7cf93ee6e
--- /dev/null
+++ b/sound/soc/loongson/loongson_i2s.c
@@ -0,0 +1,213 @@ 
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * Loongson-2K I2S master mode driver
+ *
+ * Copyright (C) 2022 Loongson Technology Corporation Limited
+ */
+
+#include <linux/module.h>
+#include <linux/platform_device.h>
+#include <linux/delay.h>
+#include <linux/pm_runtime.h>
+#include <linux/dma-mapping.h>
+#include <sound/soc.h>
+#include <linux/regmap.h>
+#include <sound/pcm_params.h>
+#include "loongson_i2s.h"
+
+#define LOONGSON_I2S_FORMATS (SNDRV_PCM_FMTBIT_S8 | \
+			SNDRV_PCM_FMTBIT_S16_LE | \
+			SNDRV_PCM_FMTBIT_S20_3LE | \
+			SNDRV_PCM_FMTBIT_S24_LE)
+
+static int loongson_i2s_trigger(struct snd_pcm_substream *substream, int cmd,
+				struct snd_soc_dai *dai)
+{
+	struct loongson_i2s *i2s = snd_soc_dai_get_drvdata(dai);
+	u32 val;
+	int ret = 0;
+
+	switch (cmd) {
+	case SNDRV_PCM_TRIGGER_START:
+		/* Enable MCLK */
+		if (i2s->rev_id == 1) {
+			regmap_update_bits(i2s->regmap, LS_I2S_CTRL,
+					   I2S_CTRL_MCLK_EN,
+					   I2S_CTRL_MCLK_EN);
+			ret = regmap_read_poll_timeout_atomic(i2s->regmap,
+						LS_I2S_CTRL, val,
+						val & I2S_CTRL_MCLK_READY,
+						10, 2000);
+			if (ret < 0)
+				dev_warn(dai->dev, "wait MCLK ready timeout\n");
+		}
+
+		/* Enable master mode */
+		regmap_update_bits(i2s->regmap, LS_I2S_CTRL, I2S_CTRL_MASTER,
+				   I2S_CTRL_MASTER);
+		if (i2s->rev_id == 1) {
+			ret = regmap_read_poll_timeout_atomic(i2s->regmap,
+						LS_I2S_CTRL, val,
+						val & I2S_CTRL_CLK_READY,
+						10, 2000);
+			if (ret < 0)
+				dev_warn(dai->dev, "wait BCLK ready timeout\n");
+		}
+		fallthrough;
+	case SNDRV_PCM_TRIGGER_RESUME:
+	case SNDRV_PCM_TRIGGER_PAUSE_RELEASE:
+		if (substream->stream == SNDRV_PCM_STREAM_PLAYBACK)
+			regmap_update_bits(i2s->regmap, LS_I2S_CTRL,
+					   I2S_CTRL_TX_EN | I2S_CTRL_TX_DMA_EN,
+					   I2S_CTRL_TX_EN | I2S_CTRL_TX_DMA_EN);
+		else
+			regmap_update_bits(i2s->regmap, LS_I2S_CTRL,
+					   I2S_CTRL_RX_EN | I2S_CTRL_RX_DMA_EN,
+					   I2S_CTRL_RX_EN | I2S_CTRL_RX_DMA_EN);
+		break;
+	case SNDRV_PCM_TRIGGER_STOP:
+	case SNDRV_PCM_TRIGGER_SUSPEND:
+	case SNDRV_PCM_TRIGGER_PAUSE_PUSH:
+		if (substream->stream == SNDRV_PCM_STREAM_PLAYBACK)
+			regmap_update_bits(i2s->regmap, LS_I2S_CTRL,
+					I2S_CTRL_TX_EN | I2S_CTRL_TX_DMA_EN, 0);
+		else
+			regmap_update_bits(i2s->regmap, LS_I2S_CTRL,
+					I2S_CTRL_RX_EN | I2S_CTRL_RX_DMA_EN, 0);
+		break;
+	default:
+		ret = -EINVAL;
+	}
+
+	return ret;
+}
+
+static int loongson_i2s_hw_params(struct snd_pcm_substream *substream,
+				  struct snd_pcm_hw_params *params,
+				  struct snd_soc_dai *dai)
+{
+	struct loongson_i2s *i2s = snd_soc_dai_get_drvdata(dai);
+	u32 clk_rate = i2s->clk_rate;
+	u32 sysclk = i2s->sysclk;
+	u32 bits = params_width(params);
+	u32 chans = params_channels(params);
+	u32 fs = params_rate(params);
+	u32 bclk_ratio, mclk_ratio;
+	u32 mclk_ratio_frac;
+	u32 val = 0;
+
+	if (i2s->rev_id == 0) {
+		bclk_ratio = DIV_ROUND_CLOSEST(clk_rate,
+					       (bits * chans * fs * 2)) - 1;
+		mclk_ratio = DIV_ROUND_CLOSEST(clk_rate, (sysclk * 2)) - 1;
+
+		/* According to 2k1000LA user manual, set bits == depth */
+		val |= (bits << 24);
+		val |= (bits << 16);
+		val |= (bclk_ratio << 8);
+		val |= mclk_ratio;
+		regmap_write(i2s->regmap, LS_I2S_CFG, val);
+	} else if (i2s->rev_id == 1) {
+		bclk_ratio = DIV_ROUND_CLOSEST(sysclk,
+					       (bits * chans * fs * 2)) - 1;
+		mclk_ratio = clk_rate / sysclk;
+		mclk_ratio_frac = DIV_ROUND_CLOSEST(((u64)clk_rate << 16),
+						    sysclk) - (mclk_ratio << 16);
+
+		regmap_read(i2s->regmap, LS_I2S_CFG, &val);
+		val |= (bits << 24);
+		val |= (bclk_ratio << 8);
+		if (substream->stream == SNDRV_PCM_STREAM_PLAYBACK)
+			val |= (bits << 16);
+		else
+			val |= bits;
+		regmap_write(i2s->regmap, LS_I2S_CFG, val);
+
+		val = (mclk_ratio_frac << 16) | mclk_ratio;
+		regmap_write(i2s->regmap, LS_I2S_CFG1, val);
+	} else
+		dev_err(i2s->dev, "I2S revision invalid\n");
+
+	return 0;
+}
+
+static int loongson_i2s_set_dai_sysclk(struct snd_soc_dai *dai, int clk_id,
+				       unsigned int freq, int dir)
+{
+	struct loongson_i2s *i2s = snd_soc_dai_get_drvdata(dai);
+
+	i2s->sysclk = freq;
+
+	return 0;
+}
+
+static const struct snd_soc_dai_ops loongson_i2s_dai_ops = {
+	.trigger	= loongson_i2s_trigger,
+	.hw_params	= loongson_i2s_hw_params,
+	.set_sysclk	= loongson_i2s_set_dai_sysclk,
+};
+
+static int loongson_i2s_dai_probe(struct snd_soc_dai *cpu_dai)
+{
+	struct loongson_i2s *i2s = dev_get_drvdata(cpu_dai->dev);
+
+	snd_soc_dai_init_dma_data(cpu_dai, &i2s->playback_dma_data,
+				  &i2s->capture_dma_data);
+	snd_soc_dai_set_drvdata(cpu_dai, i2s);
+
+	return 0;
+}
+
+struct snd_soc_dai_driver loongson_i2s_dai = {
+	.name = "loongson-i2s",
+	.probe = loongson_i2s_dai_probe,
+	.playback = {
+		.stream_name = "CPU-Playback",
+		.channels_min = 1,
+		.channels_max = 2,
+		.rates = SNDRV_PCM_RATE_8000_96000,
+		.formats = LOONGSON_I2S_FORMATS,
+	},
+	.capture = {
+		.stream_name = "CPU-Capture",
+		.channels_min = 1,
+		.channels_max = 2,
+		.rates = SNDRV_PCM_RATE_8000_96000,
+		.formats = LOONGSON_I2S_FORMATS,
+	},
+	.ops = &loongson_i2s_dai_ops,
+	.symmetric_rate = 1,
+};
+
+static int i2s_suspend(struct device *dev)
+{
+	struct loongson_i2s *i2s = dev_get_drvdata(dev);
+
+	regcache_cache_only(i2s->regmap, true);
+
+	return 0;
+}
+
+static int i2s_resume(struct device *dev)
+{
+	struct loongson_i2s *i2s = dev_get_drvdata(dev);
+	int ret;
+
+	regcache_cache_only(i2s->regmap, false);
+	regcache_mark_dirty(i2s->regmap);
+	ret = regcache_sync(i2s->regmap);
+
+	return ret;
+}
+
+const struct dev_pm_ops loongson_i2s_pm = {
+	SET_SYSTEM_SLEEP_PM_OPS(i2s_suspend, i2s_resume)
+};
+
+void loongson_i2s_init(struct loongson_i2s *i2s)
+{
+	if (i2s->rev_id == 1) {
+		regmap_write(i2s->regmap, LS_I2S_CTRL, I2S_CTRL_RESET);
+		udelay(200);
+	}
+}
diff --git a/sound/soc/loongson/loongson_i2s.h b/sound/soc/loongson/loongson_i2s.h
new file mode 100644
index 000000000000..7735eadb3bf3
--- /dev/null
+++ b/sound/soc/loongson/loongson_i2s.h
@@ -0,0 +1,70 @@ 
+/* SPDX-License-Identifier: GPL-2.0 */
+/*
+ * ALSA I2S interface for the Loongson chip
+ *
+ */
+#ifndef _LOONGSON_I2S_H
+#define _LOONGSON_I2S_H
+
+#include <linux/regmap.h>
+#include <sound/dmaengine_pcm.h>
+
+/* I2S Common Registers */
+#define LS_I2S_VER	0x00 /* I2S Version */
+#define LS_I2S_CFG	0x04 /* I2S Config */
+#define LS_I2S_CTRL	0x08 /* I2S Control */
+#define LS_I2S_RX_DATA	0x0C /* I2S DMA RX Address */
+#define LS_I2S_TX_DATA	0x10 /* I2S DMA TX Address */
+
+/* 2K2000 I2S Specify Registers */
+#define LS_I2S_CFG1	0x14 /* I2S Config1 */
+
+/* 7A2000 I2S Specify Registers */
+#define LS_I2S_TX_ORDER	0x100 /* TX DMA Order */
+#define LS_I2S_RX_ORDER 0x110 /* RX DMA Order */
+
+/* Loongson I2S Control Register */
+#define I2S_CTRL_MCLK_READY	(1 << 16) /* MCLK ready */
+#define I2S_CTRL_MASTER		(1 << 15) /* Master mode */
+#define I2S_CTRL_MSB		(1 << 14) /* MSB bit order */
+#define I2S_CTRL_RX_EN		(1 << 13) /* RX enable */
+#define I2S_CTRL_TX_EN		(1 << 12) /* TX enable */
+#define I2S_CTRL_RX_DMA_EN	(1 << 11) /* DMA RX enable */
+#define I2S_CTRL_CLK_READY	(1 << 8)  /* BCLK ready */
+#define I2S_CTRL_TX_DMA_EN	(1 << 7)  /* DMA TX enable */
+#define I2S_CTRL_RESET		(1 << 4)  /* Controller soft reset */
+#define I2S_CTRL_MCLK_EN	(1 << 3)  /* Enable MCLK */
+#define I2S_CTRL_RX_INT_EN	(1 << 1)  /* RX interrupt enable */
+#define I2S_CTRL_TX_INT_EN	(1 << 0)  /* TX interrupt enable */
+
+#define LS_I2S_DRVNAME		"loongson-i2s"
+
+struct loongson_dma_data {
+	dma_addr_t dev_addr;		/* device physical address for DMA */
+	void __iomem *order_addr;	/* DMA order register */
+	u32 irq;			/* DMA irq */
+};
+
+struct loongson_i2s {
+	struct device *dev;
+	union {
+		struct snd_dmaengine_dai_dma_data playback_dma_data;
+		struct loongson_dma_data tx_dma_data;
+	};
+	union {
+		struct snd_dmaengine_dai_dma_data capture_dma_data;
+		struct loongson_dma_data rx_dma_data;
+	};
+	struct regmap *regmap;
+	void __iomem *reg_base;
+	u32 rev_id;
+	u32 clk_rate;
+	u32 sysclk;
+};
+
+extern const struct dev_pm_ops loongson_i2s_pm;
+extern struct snd_soc_dai_driver loongson_i2s_dai;
+
+void loongson_i2s_init(struct loongson_i2s *i2s);
+
+#endif
diff --git a/sound/soc/loongson/loongson_i2s_pci.c b/sound/soc/loongson/loongson_i2s_pci.c
new file mode 100644
index 000000000000..f09713b560e9
--- /dev/null
+++ b/sound/soc/loongson/loongson_i2s_pci.c
@@ -0,0 +1,500 @@ 
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * Loongson-2K I2S master mode driver
+ *
+ * Copyright (C) 2022 Loongson Technology Corporation Limited
+ */
+
+#include <linux/module.h>
+#include <linux/io-64-nonatomic-lo-hi.h>
+#include <linux/delay.h>
+#include <linux/pm_runtime.h>
+#include <linux/dma-mapping.h>
+#include <linux/acpi.h>
+#include <linux/pci.h>
+#include <sound/soc.h>
+#include <sound/pcm.h>
+#include <sound/pcm_params.h>
+#include "loongson_i2s.h"
+
+/* DMA dma_order Register */
+#define DMA_ORDER_STOP          (1 << 4) /* DMA stop */
+#define DMA_ORDER_START         (1 << 3) /* DMA start */
+#define DMA_ORDER_ASK_VALID     (1 << 2) /* DMA ask valid flag */
+#define DMA_ORDER_AXI_UNCO      (1 << 1) /* Uncache access */
+#define DMA_ORDER_ADDR_64       (1 << 0) /* 64bits address support */
+
+#define DMA_ORDER_ASK_MASK      (~0x1fUL) /* Ask addr mask */
+#define DMA_ORDER_CTRL_MASK     (0x0fUL)  /* Control mask  */
+
+#define BAR_NUM 0
+
+/*
+ * DMA registers descriptor.
+ */
+struct loongson_dma_desc {
+	u32 order;		/* Next descriptor address register */
+	u32 saddr;		/* Source address register */
+	u32 daddr;		/* Device address register */
+	u32 length;		/* Total length register */
+	u32 step_length;	/* Memory stride register */
+	u32 step_times;		/* Repeat time register */
+	u32 cmd;		/* Command register */
+	u32 stats;		/* Status register */
+	u32 order_hi;		/* Next descriptor high address register */
+	u32 saddr_hi;		/* High source address register */
+	u32 res[6];		/* Reserved */
+};
+
+struct loongson_runtime_data {
+	struct loongson_dma_data *dma_data;
+
+	struct loongson_dma_desc *dma_desc_arr;
+	dma_addr_t dma_desc_arr_phy;
+
+	struct loongson_dma_desc *dma_pos_desc;
+	dma_addr_t dma_pos_desc_phy;
+};
+
+static const struct snd_pcm_hardware ls_pcm_hardware = {
+	.info = SNDRV_PCM_INFO_MMAP |
+		SNDRV_PCM_INFO_INTERLEAVED |
+		SNDRV_PCM_INFO_MMAP_VALID |
+		SNDRV_PCM_INFO_RESUME |
+		SNDRV_PCM_INFO_PAUSE,
+	.formats = (SNDRV_PCM_FMTBIT_S8 |
+		SNDRV_PCM_FMTBIT_S16_LE |
+		SNDRV_PCM_FMTBIT_S20_3LE |
+		SNDRV_PCM_FMTBIT_S24_LE),
+	.period_bytes_min = 128,
+	.period_bytes_max = 128 * 1024,
+	.periods_min = 1,
+	.periods_max = PAGE_SIZE / sizeof(struct loongson_dma_desc),
+	.buffer_bytes_max = 1024 * 1024,
+};
+
+static struct
+loongson_dma_desc *dma_desc_save(struct loongson_runtime_data *prtd)
+{
+	void __iomem *order_reg = prtd->dma_data->order_addr;
+	u64 val;
+
+	val = (u64)prtd->dma_pos_desc_phy & DMA_ORDER_ASK_MASK;
+	val |= (readq(order_reg) & DMA_ORDER_CTRL_MASK);
+	val |= DMA_ORDER_ASK_VALID;
+	writeq(val, order_reg);
+
+	while (readl(order_reg) & DMA_ORDER_ASK_VALID)
+		udelay(2);
+
+	return prtd->dma_pos_desc;
+}
+
+static int loongson_pcm_trigger(struct snd_soc_component *component,
+				struct snd_pcm_substream *substream, int cmd)
+{
+	struct loongson_runtime_data *prtd = substream->runtime->private_data;
+	struct device *dev = substream->pcm->card->dev;
+	void __iomem *order_reg = prtd->dma_data->order_addr;
+	u64 val;
+	int ret = 0;
+
+	switch (cmd) {
+	case SNDRV_PCM_TRIGGER_START:
+	case SNDRV_PCM_TRIGGER_RESUME:
+	case SNDRV_PCM_TRIGGER_PAUSE_RELEASE:
+		val = prtd->dma_pos_desc_phy & DMA_ORDER_ASK_MASK;
+		if (dev->coherent_dma_mask == DMA_BIT_MASK(64))
+			val |= DMA_ORDER_ADDR_64;
+		else
+			val &= ~DMA_ORDER_ADDR_64;
+		val |= (readq(order_reg) & DMA_ORDER_CTRL_MASK);
+		val |= DMA_ORDER_START;
+		writeq(val, order_reg);
+
+		while ((readl(order_reg) & DMA_ORDER_START))
+			udelay(2);
+		break;
+	case SNDRV_PCM_TRIGGER_STOP:
+	case SNDRV_PCM_TRIGGER_SUSPEND:
+	case SNDRV_PCM_TRIGGER_PAUSE_PUSH:
+		dma_desc_save(prtd);
+
+		/* dma stop */
+		val = readq(order_reg) | DMA_ORDER_STOP;
+		writeq(val, order_reg);
+		udelay(1000);
+
+		break;
+	default:
+		ret = -EINVAL;
+	}
+
+	return ret;
+}
+
+static int loongson_pcm_hw_params(struct snd_soc_component *component,
+				  struct snd_pcm_substream *substream,
+				  struct snd_pcm_hw_params *params)
+{
+	struct snd_pcm_runtime *runtime = substream->runtime;
+	struct device *dev = component->dev;
+	struct loongson_runtime_data *prtd = runtime->private_data;
+	size_t buf_len = params_buffer_bytes(params);
+	size_t period_len = params_period_bytes(params);
+	dma_addr_t order_addr, mem_addr;
+	struct loongson_dma_desc *desc;
+	u32 num_periods;
+	int i;
+
+	if (buf_len % period_len) {
+		dev_err(dev, "buf len not multiply of period len\n");
+		return -EINVAL;
+	}
+
+	num_periods = buf_len / period_len;
+	if (!num_periods) {
+		dev_err(dev, "dma data too small\n");
+		return -EINVAL;
+	}
+
+	snd_pcm_set_runtime_buffer(substream, &substream->dma_buffer);
+	runtime->dma_bytes = buf_len;
+
+	/* initialize dma descriptor array */
+	mem_addr = runtime->dma_addr;
+	order_addr = prtd->dma_desc_arr_phy;
+	for (i = 0; i < num_periods; i++) {
+		desc = &prtd->dma_desc_arr[i];
+
+		/* next descriptor physical address */
+		order_addr += sizeof(*desc);
+		desc->order = lower_32_bits(order_addr | BIT(0));
+		desc->order_hi = upper_32_bits(order_addr);
+
+		desc->saddr = lower_32_bits(mem_addr);
+		desc->saddr_hi = upper_32_bits(mem_addr);
+		desc->daddr = prtd->dma_data->dev_addr;
+
+		desc->cmd = BIT(0);
+		if (substream->stream == SNDRV_PCM_STREAM_PLAYBACK)
+			desc->cmd |= BIT(12);
+
+		desc->length = period_len >> 2;
+		desc->step_length = 0;
+		desc->step_times = 1;
+
+		mem_addr += period_len;
+	}
+	if (num_periods > 0) {
+		desc = &prtd->dma_desc_arr[num_periods - 1];
+		desc->order = lower_32_bits(prtd->dma_desc_arr_phy | BIT(0));
+		desc->order_hi = upper_32_bits(prtd->dma_desc_arr_phy);
+	}
+
+	/* init position descriptor */
+	*prtd->dma_pos_desc = *prtd->dma_desc_arr;
+
+	return 0;
+}
+
+static snd_pcm_uframes_t
+loongson_pcm_pointer(struct snd_soc_component *component,
+		     struct snd_pcm_substream *substream)
+{
+	struct snd_pcm_runtime *runtime = substream->runtime;
+	struct loongson_runtime_data *prtd = runtime->private_data;
+	struct loongson_dma_desc *desc;
+	snd_pcm_uframes_t x;
+	u64 addr;
+
+	desc = dma_desc_save(prtd);
+	addr = ((u64)desc->saddr_hi << 32) | desc->saddr;
+
+	x = bytes_to_frames(runtime, addr - runtime->dma_addr);
+	if (x == runtime->buffer_size)
+		x = 0;
+	return x;
+}
+
+static irqreturn_t loongson_pcm_dma_irq(int irq, void *devid)
+{
+	struct snd_pcm_substream *substream = devid;
+
+	snd_pcm_period_elapsed(substream);
+	return IRQ_HANDLED;
+}
+
+static int loongson_pcm_open(struct snd_soc_component *component,
+			     struct snd_pcm_substream *substream)
+{
+	struct snd_pcm_runtime *runtime = substream->runtime;
+	struct snd_soc_pcm_runtime *rtd = substream->private_data;
+	struct snd_card *card = substream->pcm->card;
+	struct loongson_runtime_data *prtd;
+	struct loongson_dma_data *dma_data;
+	int ret;
+
+	/*
+	 * For mysterious reasons (and despite what the manual says)
+	 * playback samples are lost if the DMA count is not a multiple
+	 * of the DMA burst size.  Let's add a rule to enforce that.
+	 */
+	snd_pcm_hw_constraint_step(runtime, 0,
+				   SNDRV_PCM_HW_PARAM_PERIOD_BYTES, 128);
+	snd_pcm_hw_constraint_step(runtime, 0,
+				   SNDRV_PCM_HW_PARAM_BUFFER_BYTES, 128);
+	snd_pcm_hw_constraint_integer(substream->runtime,
+				      SNDRV_PCM_HW_PARAM_PERIODS);
+	snd_soc_set_runtime_hwparams(substream, &ls_pcm_hardware);
+
+	prtd = kzalloc(sizeof(*prtd), GFP_KERNEL);
+	if (!prtd)
+		return -ENOMEM;
+
+	prtd->dma_desc_arr = dma_alloc_coherent(card->dev, PAGE_SIZE,
+						&prtd->dma_desc_arr_phy,
+						GFP_KERNEL);
+	if (!prtd->dma_desc_arr) {
+		ret = -ENOMEM;
+		goto desc_err;
+	}
+
+	prtd->dma_pos_desc = dma_alloc_coherent(card->dev,
+						sizeof(*prtd->dma_pos_desc),
+						&prtd->dma_pos_desc_phy,
+						GFP_KERNEL);
+	if (!prtd->dma_pos_desc) {
+		ret = -ENOMEM;
+		goto pos_err;
+	}
+
+	dma_data = snd_soc_dai_get_dma_data(asoc_rtd_to_cpu(rtd, 0), substream);
+	ret = request_irq(dma_data->irq, loongson_pcm_dma_irq,
+			  IRQF_TRIGGER_HIGH, LS_I2S_DRVNAME, substream);
+	if (ret < 0)
+		goto irq_err;
+
+	prtd->dma_data = dma_data;
+	substream->runtime->private_data = prtd;
+
+	return 0;
+irq_err:
+	dma_free_coherent(card->dev, sizeof(*prtd->dma_pos_desc),
+			  prtd->dma_pos_desc, prtd->dma_pos_desc_phy);
+pos_err:
+	dma_free_coherent(card->dev, PAGE_SIZE, prtd->dma_desc_arr,
+			  prtd->dma_desc_arr_phy);
+desc_err:
+	kfree(prtd);
+
+	return ret;
+}
+
+static int loongson_pcm_close(struct snd_soc_component *component,
+			      struct snd_pcm_substream *substream)
+{
+	struct snd_soc_pcm_runtime *rtd = substream->private_data;
+	struct snd_card *card = substream->pcm->card;
+	struct loongson_runtime_data *prtd = substream->runtime->private_data;
+	struct loongson_dma_data *dma_data;
+
+	dma_free_coherent(card->dev, PAGE_SIZE, prtd->dma_desc_arr,
+			  prtd->dma_desc_arr_phy);
+
+	dma_free_coherent(card->dev, sizeof(*prtd->dma_pos_desc),
+			  prtd->dma_pos_desc, prtd->dma_pos_desc_phy);
+
+	dma_data = snd_soc_dai_get_dma_data(asoc_rtd_to_cpu(rtd, 0), substream);
+	free_irq(dma_data->irq, substream);
+
+	kfree(prtd);
+	return 0;
+}
+
+static int loongson_pcm_mmap(struct snd_soc_component *component,
+			     struct snd_pcm_substream *substream,
+			     struct vm_area_struct *vma)
+{
+	return remap_pfn_range(vma, vma->vm_start,
+			substream->dma_buffer.addr >> PAGE_SHIFT,
+			vma->vm_end - vma->vm_start, vma->vm_page_prot);
+}
+
+static int loongson_pcm_new(struct snd_soc_component *component,
+			    struct snd_soc_pcm_runtime *rtd)
+{
+	struct snd_pcm *pcm = rtd->pcm;
+
+	return snd_pcm_set_fixed_buffer_all(pcm, SNDRV_DMA_TYPE_DEV,
+					    pcm->card->dev,
+					    ls_pcm_hardware.buffer_bytes_max);
+}
+
+static const struct snd_soc_component_driver loongson_i2s_component = {
+	.name		= LS_I2S_DRVNAME,
+	.open		= loongson_pcm_open,
+	.close		= loongson_pcm_close,
+	.hw_params	= loongson_pcm_hw_params,
+	.trigger	= loongson_pcm_trigger,
+	.pointer	= loongson_pcm_pointer,
+	.mmap		= loongson_pcm_mmap,
+	.pcm_construct	= loongson_pcm_new,
+};
+
+static bool loongson_i2s_wr_reg(struct device *dev, unsigned int reg)
+{
+	switch (reg) {
+	case LS_I2S_CFG:
+	case LS_I2S_CTRL:
+	case LS_I2S_RX_DATA:
+	case LS_I2S_TX_DATA:
+	case LS_I2S_CFG1:
+		return true;
+	default:
+		return false;
+	};
+}
+
+static bool loongson_i2s_rd_reg(struct device *dev, unsigned int reg)
+{
+	switch (reg) {
+	case LS_I2S_VER:
+	case LS_I2S_CFG:
+	case LS_I2S_CTRL:
+	case LS_I2S_RX_DATA:
+	case LS_I2S_TX_DATA:
+	case LS_I2S_CFG1:
+		return true;
+	default:
+		return false;
+	};
+}
+
+static const struct regmap_config loongson_i2s_regmap_config = {
+	.reg_bits = 32,
+	.reg_stride = 4,
+	.val_bits = 32,
+	.max_register = LS_I2S_CFG1,
+	.writeable_reg = loongson_i2s_wr_reg,
+	.readable_reg = loongson_i2s_rd_reg,
+	.cache_type = REGCACHE_FLAT,
+};
+
+static int loongson_i2s_pci_probe(struct pci_dev *pdev,
+				  const struct pci_device_id *pid)
+{
+	const struct fwnode_handle *fwnode = pdev->dev.fwnode;
+	struct loongson_dma_data *tx_data, *rx_data;
+	struct loongson_i2s *i2s;
+	int ret;
+
+	if (pcim_enable_device(pdev)) {
+		dev_err(&pdev->dev, "pci_enable_device failed\n");
+		return -ENODEV;
+	}
+
+	ret = pci_request_region(pdev, BAR_NUM, LS_I2S_DRVNAME);
+	if (ret) {
+		dev_err(&pdev->dev, "request regions failed %d\n", ret);
+		return ret;
+	}
+
+	i2s = devm_kzalloc(&pdev->dev, sizeof(*i2s), GFP_KERNEL);
+	if (!i2s) {
+		ret = -ENOMEM;
+		goto err_release;
+	}
+	i2s->rev_id = pdev->revision;
+	i2s->dev = &pdev->dev;
+	pci_set_drvdata(pdev, i2s);
+
+	i2s->reg_base = pcim_iomap(pdev, BAR_NUM, 0);
+	if (!i2s->reg_base) {
+		dev_err(&pdev->dev, "pci_iomap_error\n");
+		ret = -EIO;
+		goto err_release;
+	}
+
+	i2s->regmap = devm_regmap_init_mmio(&pdev->dev, i2s->reg_base,
+					    &loongson_i2s_regmap_config);
+	if (IS_ERR(i2s->regmap)) {
+		dev_err(&pdev->dev, "Failed to initialize register map");
+		ret = PTR_ERR(i2s->regmap);
+		goto err_release;
+	}
+
+	tx_data = &i2s->tx_dma_data;
+	rx_data = &i2s->rx_dma_data;
+
+	tx_data->dev_addr = (dma_addr_t)i2s->reg_base + LS_I2S_TX_DATA;
+	tx_data->order_addr = i2s->reg_base + LS_I2S_TX_ORDER;
+
+	rx_data->dev_addr = (dma_addr_t)i2s->reg_base + LS_I2S_RX_DATA;
+	rx_data->order_addr = i2s->reg_base + LS_I2S_RX_ORDER;
+
+	tx_data->irq = fwnode_irq_get_byname(fwnode, "tx");
+	if (tx_data->irq < 0) {
+		dev_err(&pdev->dev, "dma tx irq invalid\n");
+		ret = tx_data->irq;
+		goto err_release;
+	}
+
+	rx_data->irq = fwnode_irq_get_byname(fwnode, "rx");
+	if (rx_data->irq < 0) {
+		dev_err(&pdev->dev, "dma rx irq invalid\n");
+		ret = rx_data->irq;
+		goto err_release;
+	}
+
+	device_property_read_u32(&pdev->dev, "clock-frequency", &i2s->clk_rate);
+	if (!i2s->clk_rate) {
+		dev_err(&pdev->dev, "clock-frequency property invalid\n");
+		ret = -EINVAL;
+		goto err_release;
+	}
+
+	dma_set_mask_and_coherent(&pdev->dev, DMA_BIT_MASK(64));
+
+	loongson_i2s_init(i2s);
+
+	ret = devm_snd_soc_register_component(&pdev->dev,
+					      &loongson_i2s_component,
+					      &loongson_i2s_dai, 1);
+	if (ret) {
+		dev_err(&pdev->dev, "register DAI failed %d\n", ret);
+		goto err_release;
+	}
+
+	return 0;
+err_release:
+	pci_release_region(pdev, BAR_NUM);
+	return ret;
+}
+
+static void loongson_i2s_pci_remove(struct pci_dev *pdev)
+{
+	pci_release_region(pdev, BAR_NUM);
+}
+
+static const struct pci_device_id loongson_i2s_ids[] = {
+	{ PCI_DEVICE(PCI_VENDOR_ID_LOONGSON, 0x7a27) },
+	{ },
+};
+MODULE_DEVICE_TABLE(pci, loongson_i2s_ids);
+
+static struct pci_driver loongson_i2s_driver = {
+	.name = "loongson-i2s-pci",
+	.id_table = loongson_i2s_ids,
+	.probe = loongson_i2s_pci_probe,
+	.remove = loongson_i2s_pci_remove,
+	.driver = {
+		.owner = THIS_MODULE,
+		.pm = pm_sleep_ptr(&loongson_i2s_pm),
+	},
+};
+module_pci_driver(loongson_i2s_driver);
+
+MODULE_DESCRIPTION("Loongson I2S Master Mode ASoC Driver");
+MODULE_AUTHOR("Loongson Technology Corporation Limited");
+MODULE_LICENSE("GPL");