ALSA: add Intel HDMI LPE audio driver for BYT/CHT-T

On Baytrail and Cherrytrail, HDaudio may be fused out or disabled
by the BIOS. This driver enables an alternate path to the i915
display registers and DMA.

Although there is no hardware path between i915 display and LPE/SST
audio clusters, this HDMI capability is referred to in the documentation
as "HDMI LPE Audio" so we keep the name for consistency. There is no
hardware path or control dependencies with the LPE/SST DSP functionality.

The hdmi-lpe-audio driver will be probed when the i915 driver creates
a child platform device.

Since this driver is neither SoC nor PCI, a new x86 folder is added
Additional indirections in the code will be cleaned up in the next series
to aid smoother DP integration
Signed-off-by: NPierre-Louis Bossart <pierre-louis.bossart@linux.intel.com>
Signed-off-by: NJerome Anand <jerome.anand@intel.com>
Signed-off-by: NTakashi Iwai <tiwai@suse.de>

sound/Kconfig

@@ -108,6 +108,8 @@ source "sound/parisc/Kconfig"
 
 source "sound/soc/Kconfig"
 
+source "sound/x86/Kconfig"
+
 endif # SND
 
 menuconfig SOUND_PRIME

sound/Makefile

@@ -5,7 +5,7 @@ obj-$(CONFIG_SOUND) += soundcore.o
 obj-$(CONFIG_SOUND_PRIME) += oss/
 obj-$(CONFIG_DMASOUND) += oss/
 obj-$(CONFIG_SND) += core/ i2c/ drivers/ isa/ pci/ ppc/ arm/ sh/ synth/ usb/ \
-	firewire/ sparc/ spi/ parisc/ pcmcia/ mips/ soc/ atmel/ hda/
+	firewire/ sparc/ spi/ parisc/ pcmcia/ mips/ soc/ atmel/ hda/ x86/
 obj-$(CONFIG_SND_AOA) += aoa/
 
 # This one must be compilable even if sound is configured out

sound/x86/Kconfig

+menuconfig SND_X86
+	tristate "X86 sound devices"
+	depends on X86
+	---help---
+	  X86 sound devices that don't fall under SoC or PCI categories
+
+if SND_X86
+
+config HDMI_LPE_AUDIO
+	tristate "HDMI audio without HDaudio on Intel Atom platforms"
+	depends on DRM_I915
+	help
+	 Choose this option to support HDMI LPE Audio mode
+
+endif	# SND_X86

sound/x86/Makefile

+snd-hdmi-lpe-audio-objs += \
+	intel_hdmi_lpe_audio.o
+
+obj-$(CONFIG_HDMI_LPE_AUDIO) += snd-hdmi-lpe-audio.o

sound/x86/intel_hdmi_lpe_audio.c

+/*
+ *  intel_hdmi_lpe_audio.c - Intel HDMI LPE audio driver for Atom platforms
+ *
+ *  Copyright (C) 2016 Intel Corp
+ *  Authors:
+ *		Jerome Anand <jerome.anand@intel.com>
+ *		Aravind Siddappaji <aravindx.siddappaji@intel.com>
+ *  ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
+ *
+ *  This program is free software; you can redistribute it and/or modify
+ *  it under the terms of the GNU General Public License as published by
+ *  the Free Software Foundation; version 2 of the License.
+ *
+ *  This program is distributed in the hope that it will be useful, but
+ *  WITHOUT ANY WARRANTY; without even the implied warranty of
+ *  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+ *  General Public License for more details.
+ *
+ * ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
+ */
+
+#include <linux/platform_device.h>
+#include <linux/irqreturn.h>
+#include <linux/interrupt.h>
+#include <linux/io.h>
+#include <linux/slab.h>
+#include <linux/module.h>
+#include <linux/pci.h>
+#include <sound/core.h>
+#include <sound/pcm.h>
+#include <sound/pcm_params.h>
+#include <sound/initval.h>
+#include <sound/control.h>
+#include <sound/initval.h>
+#include <drm/intel_lpe_audio.h>
+#include "intel_hdmi_lpe_audio.h"
+
+/* globals*/
+static struct platform_device *hlpe_pdev;
+static int hlpe_state;
+static union otm_hdmi_eld_t hlpe_eld;
+
+struct hdmi_lpe_audio_ctx {
+	int irq;
+	void __iomem *mmio_start;
+	had_event_call_back had_event_callbacks;
+	struct snd_intel_had_interface *had_interface;
+	void *had_pvt_data;
+	int tmds_clock_speed;
+	unsigned int had_config_offset;
+	int hdmi_audio_interrupt_mask;
+	struct work_struct hdmi_audio_wq;
+};
+
+static void hdmi_set_eld(void *eld)
+{
+	int size;
+
+	BUILD_BUG_ON(sizeof(hlpe_eld) > HDMI_MAX_ELD_BYTES);
+
+	size = sizeof(hlpe_eld);
+	memcpy((void *)&hlpe_eld, eld, size);
+}
+
+static int hdmi_get_eld(void *eld)
+{
+	u8 *eld_data = (u8 *)&hlpe_eld;
+
+	memcpy(eld, (void *)&hlpe_eld, sizeof(hlpe_eld));
+
+	print_hex_dump_bytes("eld: ", DUMP_PREFIX_NONE, eld_data,
+			sizeof(hlpe_eld));
+	return 0;
+}
+
+
+static struct hdmi_lpe_audio_ctx *get_hdmi_context(void)
+{
+	struct hdmi_lpe_audio_ctx *ctx;
+
+	ctx = platform_get_drvdata(hlpe_pdev);
+	return ctx;
+}
+
+/*
+ * return whether HDMI audio device is busy.
+ */
+bool mid_hdmi_audio_is_busy(void *ddev)
+{
+	struct hdmi_lpe_audio_ctx *ctx;
+	int hdmi_audio_busy = 0;
+	struct hdmi_audio_event hdmi_audio_event;
+
+	dev_dbg(&hlpe_pdev->dev, "%s: Enter",  __func__);
+
+	ctx = platform_get_drvdata(hlpe_pdev);
+
+	if (hlpe_state == hdmi_connector_status_disconnected) {
+		/* HDMI is not connected, assuming audio device is idle. */
+		return false;
+	}
+
+	if (ctx->had_interface) {
+		hdmi_audio_event.type = HAD_EVENT_QUERY_IS_AUDIO_BUSY;
+		hdmi_audio_busy = ctx->had_interface->query(
+				ctx->had_pvt_data,
+				hdmi_audio_event);
+		return hdmi_audio_busy != 0;
+	}
+	return false;
+}
+
+/*
+ * return true if HDMI audio device is suspended/ disconnected
+ */
+bool mid_hdmi_audio_suspend(void *ddev)
+{
+	struct hdmi_lpe_audio_ctx *ctx;
+	struct hdmi_audio_event hdmi_audio_event;
+	int ret = 0;
+
+	ctx = platform_get_drvdata(hlpe_pdev);
+
+	if (hlpe_state == hdmi_connector_status_disconnected) {
+		/* HDMI is not connected, assuming audio device
+		 * is suspended already.
+		 */
+		return true;
+	}
+
+	dev_dbg(&hlpe_pdev->dev, "%s: hlpe_state %d",  __func__,
+			hlpe_state);
+
+	if (ctx->had_interface) {
+		hdmi_audio_event.type = 0;
+		ret = ctx->had_interface->suspend(ctx->had_pvt_data,
+				hdmi_audio_event);
+		return (ret == 0) ? true : false;
+	}
+	return true;
+}
+
+void mid_hdmi_audio_resume(void *ddev)
+{
+	struct hdmi_lpe_audio_ctx *ctx;
+
+	ctx = platform_get_drvdata(hlpe_pdev);
+
+	if (hlpe_state == hdmi_connector_status_disconnected) {
+		/* HDMI is not connected, there is no need
+		 * to resume audio device.
+		 */
+		return;
+	}
+
+	dev_dbg(&hlpe_pdev->dev, "%s: hlpe_state %d",  __func__, hlpe_state);
+
+	if (ctx->had_interface)
+		ctx->had_interface->resume(ctx->had_pvt_data);
+}
+
+void mid_hdmi_audio_signal_event(enum had_event_type event)
+{
+	struct hdmi_lpe_audio_ctx *ctx;
+
+	dev_dbg(&hlpe_pdev->dev, "%s: Enter\n", __func__);
+
+	ctx = platform_get_drvdata(hlpe_pdev);
+
+	/* The handler is protected in the respective
+	 * event handlers to avoid races
+	 */
+	if (ctx->had_event_callbacks)
+		(*ctx->had_event_callbacks)(event,
+			ctx->had_pvt_data);
+}
+
+/**
+ * used to write into display controller HDMI audio registers.
+ */
+static int hdmi_audio_write(u32 reg, u32 val)
+{
+	struct hdmi_lpe_audio_ctx *ctx;
+
+	ctx = platform_get_drvdata(hlpe_pdev);
+
+	dev_dbg(&hlpe_pdev->dev, "%s: reg[0x%x] = 0x%x\n", __func__, reg, val);
+
+	iowrite32(val, (ctx->mmio_start+reg));
+
+	return 0;
+}
+
+/**
+ * used to get the register value read from
+ * display controller HDMI audio registers.
+ */
+static int hdmi_audio_read(u32 reg, u32 *val)
+{
+	struct hdmi_lpe_audio_ctx *ctx;
+
+	ctx = platform_get_drvdata(hlpe_pdev);
+	*val = ioread32(ctx->mmio_start+reg);
+	dev_dbg(&hlpe_pdev->dev, "%s: reg[0x%x] = 0x%x\n", __func__, reg, *val);
+	return 0;
+}
+
+/**
+ * used to update the masked bits in display controller HDMI
+ * audio registers.
+ */
+static int hdmi_audio_rmw(u32 reg, u32 val, u32 mask)
+{
+	struct hdmi_lpe_audio_ctx *ctx;
+	u32 val_tmp = 0;
+
+	ctx = platform_get_drvdata(hlpe_pdev);
+
+	val_tmp = (val & mask) |
+			((ioread32(ctx->mmio_start + reg)) & ~mask);
+
+	iowrite32(val_tmp, (ctx->mmio_start+reg));
+	dev_dbg(&hlpe_pdev->dev, "%s: reg[0x%x] = 0x%x\n", __func__,
+				reg, val_tmp);
+
+	return 0;
+}
+
+/**
+ * used to return the HDMI audio capabilities.
+ * e.g. resolution, frame rate.
+ */
+static int hdmi_audio_get_caps(enum had_caps_list get_element,
+			void *capabilities)
+{
+	struct hdmi_lpe_audio_ctx *ctx;
+	int ret = 0;
+
+	ctx = get_hdmi_context();
+
+	dev_dbg(&hlpe_pdev->dev, "%s: Enter\n", __func__);
+
+	switch (get_element) {
+	case HAD_GET_ELD:
+		ret = hdmi_get_eld(capabilities);
+		break;
+	case HAD_GET_DISPLAY_RATE:
+		/* ToDo: Verify if sampling freq logic is correct */
+		*(u32 *)capabilities = ctx->tmds_clock_speed;
+		dev_dbg(&hlpe_pdev->dev, "%s: tmds_clock_speed = 0x%x\n",
+				__func__, ctx->tmds_clock_speed);
+		break;
+	default:
+		break;
+	}
+
+	return ret;
+}
+
+/**
+ * used to get the current hdmi base address
+ */
+int hdmi_audio_get_register_base(u32 **reg_base,
+		u32 *config_offset)
+{
+	struct hdmi_lpe_audio_ctx *ctx;
+
+	ctx = platform_get_drvdata(hlpe_pdev);
+	*reg_base = (u32 *)(ctx->mmio_start);
+	*config_offset = ctx->had_config_offset;
+	dev_dbg(&hlpe_pdev->dev, "%s: reg_base = 0x%p, cfg_off = 0x%x\n",
+				__func__, *reg_base, *config_offset);
+	return 0;
+}
+
+/**
+ * used to set the HDMI audio capabilities.
+ * e.g. Audio INT.
+ */
+int hdmi_audio_set_caps(enum had_caps_list set_element,
+			void *capabilties)
+{
+	struct hdmi_lpe_audio_ctx *ctx;
+
+	ctx = platform_get_drvdata(hlpe_pdev);
+
+	dev_dbg(&hlpe_pdev->dev, "%s: cap_id = 0x%x\n", __func__, set_element);
+
+	switch (set_element) {
+	case HAD_SET_ENABLE_AUDIO_INT:
+		{
+			u32 status_reg;
+
+			hdmi_audio_read(AUD_HDMI_STATUS_v2 +
+				ctx->had_config_offset, &status_reg);
+			status_reg |=
+				HDMI_AUDIO_BUFFER_DONE | HDMI_AUDIO_UNDERRUN;
+			hdmi_audio_write(AUD_HDMI_STATUS_v2 +
+				ctx->had_config_offset, status_reg);
+			hdmi_audio_read(AUD_HDMI_STATUS_v2 +
+				ctx->had_config_offset, &status_reg);
+
+		}
+		break;
+	default:
+		break;
+	}
+
+	return 0;
+}
+
+static struct  hdmi_audio_registers_ops hdmi_audio_reg_ops = {
+	.hdmi_audio_get_register_base = hdmi_audio_get_register_base,
+	.hdmi_audio_read_register = hdmi_audio_read,
+	.hdmi_audio_write_register = hdmi_audio_write,
+	.hdmi_audio_read_modify = hdmi_audio_rmw,
+};
+
+static struct hdmi_audio_query_set_ops hdmi_audio_get_set_ops = {
+	.hdmi_audio_get_caps = hdmi_audio_get_caps,
+	.hdmi_audio_set_caps = hdmi_audio_set_caps,
+};
+
+int mid_hdmi_audio_setup(
+		had_event_call_back audio_callbacks,
+		struct hdmi_audio_registers_ops *reg_ops,
+		struct hdmi_audio_query_set_ops *query_ops)
+{
+	struct hdmi_lpe_audio_ctx *ctx;
+
+	ctx = platform_get_drvdata(hlpe_pdev);
+
+	dev_dbg(&hlpe_pdev->dev, "%s: called\n",  __func__);
+
+	reg_ops->hdmi_audio_get_register_base =
+		(hdmi_audio_reg_ops.hdmi_audio_get_register_base);
+	reg_ops->hdmi_audio_read_register =
+		(hdmi_audio_reg_ops.hdmi_audio_read_register);
+	reg_ops->hdmi_audio_write_register =
+		(hdmi_audio_reg_ops.hdmi_audio_write_register);
+	reg_ops->hdmi_audio_read_modify =
+		(hdmi_audio_reg_ops.hdmi_audio_read_modify);
+	query_ops->hdmi_audio_get_caps =
+		hdmi_audio_get_set_ops.hdmi_audio_get_caps;
+	query_ops->hdmi_audio_set_caps =
+		hdmi_audio_get_set_ops.hdmi_audio_set_caps;
+
+	ctx->had_event_callbacks = audio_callbacks;
+
+	return 0;
+}
+
+static void _had_wq(struct work_struct *work)
+{
+	mid_hdmi_audio_signal_event(HAD_EVENT_HOT_PLUG);
+}
+
+int mid_hdmi_audio_register(struct snd_intel_had_interface *driver,
+				void *had_data)
+{
+	struct hdmi_lpe_audio_ctx *ctx;
+
+	ctx = platform_get_drvdata(hlpe_pdev);
+
+	dev_dbg(&hlpe_pdev->dev, "%s: called\n", __func__);
+
+	ctx->had_pvt_data = had_data;
+	ctx->had_interface = driver;
+
+	/* The Audio driver is loading now and we need to notify
+	 * it if there is an HDMI device attached
+	 */
+	INIT_WORK(&ctx->hdmi_audio_wq, _had_wq);
+	dev_dbg(&hlpe_pdev->dev, "%s: Scheduling HDMI audio work queue\n",
+				__func__);
+	schedule_work(&ctx->hdmi_audio_wq);
+
+	return 0;
+}
+
+static irqreturn_t display_pipe_interrupt_handler(int irq, void *dev_id)
+{
+	u32 audio_stat, audio_reg;
+
+	struct hdmi_lpe_audio_ctx *ctx;
+
+	dev_dbg(&hlpe_pdev->dev, "%s: Enter\n", __func__);
+
+	ctx = platform_get_drvdata(hlpe_pdev);
+
+	audio_reg = ctx->had_config_offset + AUD_HDMI_STATUS_v2;
+	hdmi_audio_read(audio_reg, &audio_stat);
+
+	if (audio_stat & HDMI_AUDIO_UNDERRUN) {
+		hdmi_audio_write(audio_reg, HDMI_AUDIO_UNDERRUN);
+		mid_hdmi_audio_signal_event(
+				HAD_EVENT_AUDIO_BUFFER_UNDERRUN);
+	}
+
+	if (audio_stat & HDMI_AUDIO_BUFFER_DONE) {
+		hdmi_audio_write(audio_reg, HDMI_AUDIO_BUFFER_DONE);
+		mid_hdmi_audio_signal_event(
+				HAD_EVENT_AUDIO_BUFFER_DONE);
+	}
+
+	return IRQ_HANDLED;
+}
+
+static void notify_audio_lpe(void *audio_ptr)
+{
+	struct hdmi_lpe_audio_ctx *ctx = get_hdmi_context();
+	struct intel_hdmi_lpe_audio_pdata *pdata = hlpe_pdev->dev.platform_data;
+	struct intel_hdmi_lpe_audio_eld *eld = audio_ptr;
+
+	if (pdata->hdmi_connected != true) {
+
+		dev_dbg(&hlpe_pdev->dev, "%s: Event: HAD_NOTIFY_HOT_UNPLUG\n",
+			__func__);
+
+		if (hlpe_state == hdmi_connector_status_connected) {
+
+			hlpe_state =
+				hdmi_connector_status_disconnected;
+
+			mid_hdmi_audio_signal_event(
+				HAD_EVENT_HOT_UNPLUG);
+		} else
+			dev_dbg(&hlpe_pdev->dev, "%s: Already Unplugged!\n",
+				__func__);
+
+	} else if (eld != NULL) {
+
+		hdmi_set_eld(eld->eld_data);
+
+		mid_hdmi_audio_signal_event(HAD_EVENT_HOT_PLUG);
+
+		hlpe_state = hdmi_connector_status_connected;
+
+		dev_dbg(&hlpe_pdev->dev, "%s: HAD_NOTIFY_ELD : port = %d, tmds = %d\n",
+			__func__, eld->port_id,	pdata->tmds_clock_speed);
+
+		if (pdata->tmds_clock_speed) {
+			ctx->tmds_clock_speed = pdata->tmds_clock_speed;
+			mid_hdmi_audio_signal_event(HAD_EVENT_MODE_CHANGING);
+		}
+	} else
+		dev_dbg(&hlpe_pdev->dev, "%s: Event: NULL EDID!!\n", __func__);
+}
+
+/**
+ * hdmi_lpe_audio_probe - start bridge with i915
+ *
+ * This function is called when the i915 driver creates the hdmi-lpe-audio
+ * platform device. Card creation is deferred until a hot plug event is
+ * received
+ */
+static int hdmi_lpe_audio_probe(struct platform_device *pdev)
+{
+	struct hdmi_lpe_audio_ctx *ctx;
+	struct intel_hdmi_lpe_audio_pdata *pdata;
+	int irq;
+	struct resource *res_mmio;
+	void __iomem *mmio_start;
+	int ret = 0;
+	unsigned long flag_irq;
+	static const struct pci_device_id cherryview_ids[] = {
+		{PCI_DEVICE(0x8086, 0x22b0)},
+		{PCI_DEVICE(0x8086, 0x22b1)},
+		{PCI_DEVICE(0x8086, 0x22b2)},
+		{PCI_DEVICE(0x8086, 0x22b3)},
+		{}
+	};
+
+	dev_dbg(&hlpe_pdev->dev, "Enter %s\n", __func__);
+
+	/*TBD:remove globals*/
+	hlpe_pdev = pdev;
+	hlpe_state = hdmi_connector_status_disconnected;
+
+	/* get resources */
+	irq = platform_get_irq(pdev, 0);
+	if (irq < 0) {
+		dev_err(&hlpe_pdev->dev, "Could not get irq resource\n");
+		return -ENODEV;
+	}
+
+	res_mmio = platform_get_resource(pdev, IORESOURCE_MEM, 0);
+	if (!res_mmio) {
+		dev_err(&hlpe_pdev->dev, "Could not get IO_MEM resources\n");
+		return -ENXIO;
+	}
+
+	dev_dbg(&hlpe_pdev->dev, "%s: mmio_start = 0x%x, mmio_end = 0x%x\n",
+		__func__, (unsigned int)res_mmio->start,
+		(unsigned int)res_mmio->end);
+
+	mmio_start = ioremap_nocache(res_mmio->start,
+				(size_t)((res_mmio->end - res_mmio->start)
+						+ 1));
+	if (!mmio_start) {
+		dev_err(&hlpe_pdev->dev, "Could not get ioremap\n");
+		return -EACCES;
+	}
+
+	/* setup interrupt handler */
+	ret = request_irq(irq, display_pipe_interrupt_handler,
+			0,
+			pdev->name,
+			NULL);
+	if (ret < 0) {
+		dev_err(&hlpe_pdev->dev, "request_irq failed\n");
+		iounmap(mmio_start);
+		return -ENODEV;
+	}
+
+	/* alloc and save context */
+	ctx = kzalloc(sizeof(*ctx), GFP_KERNEL);
+	if (ctx == NULL) {
+		free_irq(irq, NULL);
+		iounmap(mmio_start);
+		return -ENOMEM;
+	}
+
+	ctx->irq = irq;
+	dev_dbg(&hlpe_pdev->dev, "hdmi lpe audio: irq num = %d\n", irq);
+	ctx->mmio_start = mmio_start;
+	ctx->tmds_clock_speed = DIS_SAMPLE_RATE_148_5;
+
+	if (pci_dev_present(cherryview_ids)) {
+		dev_dbg(&hlpe_pdev->dev, "%s: Cherrytrail LPE - Detected\n",
+				__func__);
+		ctx->had_config_offset = AUDIO_HDMI_CONFIG_C;
+	} else {
+		dev_dbg(&hlpe_pdev->dev, "%s: Baytrail LPE - Assume\n",
+				__func__);
+		ctx->had_config_offset = AUDIO_HDMI_CONFIG_A;
+	}
+
+	pdata = pdev->dev.platform_data;
+
+	if (pdata == NULL) {
+		dev_err(&hlpe_pdev->dev, "%s: quit: pdata not allocated by i915!!\n", __func__);
+		kfree(ctx);
+		free_irq(irq, NULL);
+		iounmap(mmio_start);
+		return -ENOMEM;
+	}
+
+	platform_set_drvdata(pdev, ctx);
+
+	dev_dbg(&hlpe_pdev->dev, "hdmi lpe audio: setting pin eld notify callback\n");
+
+	spin_lock_irqsave(&pdata->lpe_audio_slock, flag_irq);
+	pdata->notify_audio_lpe = notify_audio_lpe;
+
+	if (pdata->notify_pending) {
+
+		dev_dbg(&hlpe_pdev->dev, "%s: handle pending notification\n", __func__);
+		notify_audio_lpe(&pdata->eld);
+		pdata->notify_pending = false;
+	}
+	spin_unlock_irqrestore(&pdata->lpe_audio_slock, flag_irq);
+
+	return ret;
+}
+
+/**
+ * hdmi_lpe_audio_remove - stop bridge with i915
+ *
+ * This function is called when the platform device is destroyed. The sound
+ * card should have been removed on hot plug event.
+ */
+static int hdmi_lpe_audio_remove(struct platform_device *pdev)
+{
+	struct hdmi_lpe_audio_ctx *ctx;
+
+	dev_dbg(&hlpe_pdev->dev, "Enter %s\n", __func__);
+
+	/* get context, release resources */
+	ctx = platform_get_drvdata(pdev);
+	iounmap(ctx->mmio_start);
+	free_irq(ctx->irq, NULL);
+	kfree(ctx);
+	return 0;
+}
+
+static int hdmi_lpe_audio_suspend(struct platform_device *pt_dev,
+				pm_message_t state)
+{
+	dev_dbg(&hlpe_pdev->dev, "Enter %s\n", __func__);
+	mid_hdmi_audio_suspend(NULL);
+	return 0;
+}
+
+static int hdmi_lpe_audio_resume(struct platform_device *pt_dev)
+{
+	dev_dbg(&hlpe_pdev->dev, "Enter %s\n", __func__);
+	mid_hdmi_audio_resume(NULL);
+	return 0;
+}
+
+static struct platform_driver hdmi_lpe_audio_driver = {
+	.driver		= {
+		.name  = "hdmi-lpe-audio",
+	},
+	.probe          = hdmi_lpe_audio_probe,
+	.remove		= hdmi_lpe_audio_remove,
+	.suspend	= hdmi_lpe_audio_suspend,
+	.resume		= hdmi_lpe_audio_resume
+};
+
+module_platform_driver(hdmi_lpe_audio_driver);
+MODULE_LICENSE("GPL v2");
+MODULE_ALIAS("platform:hdmi_lpe_audio");

sound/x86/intel_hdmi_lpe_audio.h

+/*
+ *   intel_hdmi_lpe_audio.h - Intel HDMI LPE audio driver
+ *
+ *  Copyright (C) 2016 Intel Corp
+ *  Authors:	Sailaja Bandarupalli <sailaja.bandarupalli@intel.com>
+ *		Ramesh Babu K V <ramesh.babu@intel.com>
+ *		Vaibhav Agarwal <vaibhav.agarwal@intel.com>
+ *		Jerome Anand <jerome.anand@intel.com>
+ *		Aravind Siddappaji <aravindx.siddappaji@intel.com>
+ *  ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
+ *
+ *  This program is free software; you can redistribute it and/or modify
+ *  it under the terms of the GNU General Public License as published by
+ *  the Free Software Foundation; version 2 of the License.
+ *
+ *  This program is distributed in the hope that it will be useful, but
+ *  WITHOUT ANY WARRANTY; without even the implied warranty of
+ *  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+ *  General Public License for more details.
+ *
+ * ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
+ */
+#ifndef __INTEL_HDMI_LPE_AUDIO_H
+#define __INTEL_HDMI_LPE_AUDIO_H
+
+#include <linux/types.h>
+#include <sound/initval.h>
+#include <linux/version.h>
+#include <linux/pm_runtime.h>
+#include <sound/asoundef.h>
+#include <sound/control.h>
+#include <sound/pcm.h>
+
+#define HMDI_LPE_AUDIO_DRIVER_NAME		"intel-hdmi-lpe-audio"
+#define HAD_MAX_DEVICES		1
+#define HAD_MIN_CHANNEL		2
+#define HAD_MAX_CHANNEL		8
+#define HAD_NUM_OF_RING_BUFS	4
+
+/* Assume 192KHz, 8channel, 25msec period */
+#define HAD_MAX_BUFFER		(600*1024)
+#define HAD_MIN_BUFFER		(32*1024)
+#define HAD_MAX_PERIODS		4
+#define HAD_MIN_PERIODS		4
+#define HAD_MAX_PERIOD_BYTES	(HAD_MAX_BUFFER/HAD_MIN_PERIODS)
+#define HAD_MIN_PERIOD_BYTES	256
+#define HAD_FIFO_SIZE		0 /* fifo not being used */
+#define MAX_SPEAKERS		8
+
+#define AUD_SAMPLE_RATE_32	32000
+#define AUD_SAMPLE_RATE_44_1	44100
+#define AUD_SAMPLE_RATE_48	48000
+#define AUD_SAMPLE_RATE_88_2	88200
+#define AUD_SAMPLE_RATE_96	96000
+#define AUD_SAMPLE_RATE_176_4	176400
+#define AUD_SAMPLE_RATE_192	192000
+
+#define HAD_MIN_RATE		AUD_SAMPLE_RATE_32
+#define HAD_MAX_RATE		AUD_SAMPLE_RATE_192
+
+#define DIS_SAMPLE_RATE_25_2	25200
+#define DIS_SAMPLE_RATE_27	27000
+#define DIS_SAMPLE_RATE_54	54000
+#define DIS_SAMPLE_RATE_74_25	74250
+#define DIS_SAMPLE_RATE_148_5	148500
+#define HAD_REG_WIDTH		0x08
+#define HAD_MAX_HW_BUFS		0x04
+#define HAD_MAX_DIP_WORDS		16
+#define INTEL_HAD		"IntelHdmiLpeAudio"
+
+/* _AUD_CONFIG register MASK */
+#define AUD_CONFIG_MASK_UNDERRUN	0xC0000000
+#define AUD_CONFIG_MASK_SRDBG		0x00000002
+#define AUD_CONFIG_MASK_FUNCRST		0x00000001
+
+#define MAX_CNT			0xFF
+#define HAD_SUSPEND_DELAY	1000
+
+#define OTM_HDMI_ELD_SIZE 128
+
+union otm_hdmi_eld_t {
+	unsigned char eld_data[OTM_HDMI_ELD_SIZE];
+	struct {
+		/* Byte[0] = ELD Version Number */
+		union {
+			unsigned char   byte0;
+			struct {
+				unsigned char reserved:3; /* Reserf */
+				unsigned char eld_ver:5; /* ELD Version Number */
+				/* 00000b - reserved
+				 * 00001b - first rev, obsoleted
+				 * 00010b - version 2, supporting CEA version
+				 *			861D or below
+				 * 00011b:11111b - reserved
+				 * for future
+				 */
+			};
+		};
+
+		/* Byte[1] = Vendor Version Field */
+		union {
+			unsigned char vendor_version;
+			struct {
+				unsigned char reserved1:3;
+				unsigned char veld_ver:5; /* Version number of the ELD
+						     * extension. This value is
+						     * provisioned and unique to
+						     * each vendor.
+						     */
+			};
+		};
+
+		/* Byte[2] = Baseline Length field */
+		unsigned char baseline_eld_length; /* Length of the Baseline structure
+					      *	divided by Four.
+					      */
+
+		/* Byte [3] = Reserved for future use */
+		unsigned char byte3;
+
+		/* Starting of the BaseLine EELD structure
+		 * Byte[4] = Monitor Name Length
+		 */
+		union {
+			unsigned char byte4;
+			struct {
+				unsigned char mnl:5;
+				unsigned char cea_edid_rev_id:3;
+			};
+		};
+
+		/* Byte[5] = Capabilities */
+		union {
+			unsigned char capabilities;
+			struct {
+				unsigned char hdcp:1; /* HDCP support */
+				unsigned char ai_support:1;   /* AI support */
+				unsigned char connection_type:2; /* Connection type
+							    * 00 - HDMI
+							    * 01 - DP
+							    * 10 -11  Reserved
+							    * for future
+							    * connection types
+							    */
+				unsigned char sadc:4; /* Indicates number of 3 bytes
+						 * Short Audio Descriptors.
+						 */
+			};
+		};
+
+		/* Byte[6] = Audio Synch Delay */
+		unsigned char audio_synch_delay; /* Amount of time reported by the
+					    * sink that the video trails audio
+					    * in milliseconds.
+					    */
+
+		/* Byte[7] = Speaker Allocation Block */
+		union {
+			unsigned char speaker_allocation_block;
+			struct {
+				unsigned char flr:1; /*Front Left and Right channels*/
+				unsigned char lfe:1; /*Low Frequency Effect channel*/
+				unsigned char fc:1;  /*Center transmission channel*/
+				unsigned char rlr:1; /*Rear Left and Right channels*/
+				unsigned char rc:1; /*Rear Center channel*/
+				unsigned char flrc:1; /*Front left and Right of Center
+						 *transmission channels
+						 */
+				unsigned char rlrc:1; /*Rear left and Right of Center
+						 *transmission channels
+						 */
+				unsigned char reserved3:1; /* Reserved */
+			};
+		};
+
+		/* Byte[8 - 15] - 8 Byte port identification value */
+		unsigned char port_id_value[8];
+
+		/* Byte[16 - 17] - 2 Byte Manufacturer ID */
+		unsigned char manufacturer_id[2];
+
+		/* Byte[18 - 19] - 2 Byte Product ID */
+		unsigned char product_id[2];
+
+		/* Byte [20-83] - 64 Bytes of BaseLine Data */
+		unsigned char mn_sand_sads[64]; /* This will include
+					   * - ASCII string of Monitor name
+					   * - List of 3 byte SADs
+					   * - Zero padding
+					   */
+
+		/* Vendor ELD Block should continue here!
+		 * No Vendor ELD block defined as of now.
+		 */
+	} __packed;
+};
+
+/**
+ * enum had_status - Audio stream states
+ *
+ * @STREAM_INIT: Stream initialized
+ * @STREAM_RUNNING: Stream running
+ * @STREAM_PAUSED: Stream paused
+ * @STREAM_DROPPED: Stream dropped
+ */
+enum had_stream_status {
+	STREAM_INIT = 0,
+	STREAM_RUNNING = 1,
+	STREAM_PAUSED = 2,
+	STREAM_DROPPED = 3
+};
+
+/**
+ * enum had_status_stream - HAD stream states
+ */
+enum had_status_stream {
+	HAD_INIT = 0,
+	HAD_RUNNING_STREAM,
+};
+
+enum had_drv_status {
+	HAD_DRV_CONNECTED,
+	HAD_DRV_RUNNING,
+	HAD_DRV_DISCONNECTED,
+	HAD_DRV_SUSPENDED,
+	HAD_DRV_ERR,
+};
+
+/* enum intel_had_aud_buf_type - HDMI controller ring buffer types */
+enum intel_had_aud_buf_type {
+	HAD_BUF_TYPE_A = 0,
+	HAD_BUF_TYPE_B = 1,
+	HAD_BUF_TYPE_C = 2,
+	HAD_BUF_TYPE_D = 3,
+};
+
+enum num_aud_ch {
+	CH_STEREO = 0,
+	CH_THREE_FOUR = 1,
+	CH_FIVE_SIX = 2,
+	CH_SEVEN_EIGHT = 3
+};
+
+/* HDMI Controller register offsets - audio domain common */
+/* Base address for below regs = 0x65000 */
+enum hdmi_ctrl_reg_offset_common {
+	AUDIO_HDMI_CONFIG_A	= 0x000,
+	AUDIO_HDMI_CONFIG_B = 0x800,
+	AUDIO_HDMI_CONFIG_C = 0x900,
+};
+/* HDMI controller register offsets */
+enum hdmi_ctrl_reg_offset_v1 {
+	AUD_CONFIG		= 0x0,
+	AUD_CH_STATUS_0		= 0x08,
+	AUD_CH_STATUS_1		= 0x0C,
+	AUD_HDMI_CTS		= 0x10,
+	AUD_N_ENABLE		= 0x14,
+	AUD_SAMPLE_RATE		= 0x18,
+	AUD_BUF_CONFIG		= 0x20,
+	AUD_BUF_CH_SWAP		= 0x24,
+	AUD_BUF_A_ADDR		= 0x40,
+	AUD_BUF_A_LENGTH	= 0x44,
+	AUD_BUF_B_ADDR		= 0x48,
+	AUD_BUF_B_LENGTH	= 0x4c,
+	AUD_BUF_C_ADDR		= 0x50,
+	AUD_BUF_C_LENGTH	= 0x54,
+	AUD_BUF_D_ADDR		= 0x58,
+	AUD_BUF_D_LENGTH	= 0x5c,
+	AUD_CNTL_ST		= 0x60,
+	AUD_HDMI_STATUS		= 0x68,
+	AUD_HDMIW_INFOFR	= 0x114,
+};
+
+/*
+ * Delta changes in HDMI controller register offsets
+ * compare to v1 version
+ */
+
+enum hdmi_ctrl_reg_offset_v2 {
+	AUD_HDMI_STATUS_v2	= 0x64,
+	AUD_HDMIW_INFOFR_v2	= 0x68,
+};
+
+/*
+ *	CEA speaker placement:
+ *
+ *	FL  FLC   FC   FRC   FR
+ *
+ *						LFE
+ *
+ *	RL  RLC   RC   RRC   RR
+ *
+ *	The Left/Right Surround channel _notions_ LS/RS in SMPTE 320M
+ *	corresponds to CEA RL/RR; The SMPTE channel _assignment_ C/LFE is
+ *	swapped to CEA LFE/FC.
+ */
+enum cea_speaker_placement {
+	FL  = (1 <<  0),        /* Front Left           */
+	FC  = (1 <<  1),        /* Front Center         */
+	FR  = (1 <<  2),        /* Front Right          */
+	FLC = (1 <<  3),        /* Front Left Center    */
+	FRC = (1 <<  4),        /* Front Right Center   */
+	RL  = (1 <<  5),        /* Rear Left            */
+	RC  = (1 <<  6),        /* Rear Center          */
+	RR  = (1 <<  7),        /* Rear Right           */
+	RLC = (1 <<  8),        /* Rear Left Center     */
+	RRC = (1 <<  9),        /* Rear Right Center    */
+	LFE = (1 << 10),        /* Low Frequency Effect */
+};
+
+struct cea_channel_speaker_allocation {
+	int ca_index;
+	int speakers[8];
+
+	/* derived values, just for convenience */
+	int channels;
+	int spk_mask;
+};
+
+struct channel_map_table {
+	unsigned char map;              /* ALSA API channel map position */
+	unsigned char cea_slot;         /* CEA slot value */
+	int spk_mask;                   /* speaker position bit mask */
+};
+
+/**
+ * union aud_cfg - Audio configuration
+ *
+ * @cfg_regx: individual register bits
+ * @cfg_regval: full register value
+ *
+ */
+union aud_cfg {
+	struct {
+		u32 aud_en:1;
+		u32 layout:1;
+		u32 fmt:2;
+		u32 num_ch:2;
+		u32 rsvd0:1;
+		u32 set:1;
+		u32 flat:1;
+		u32 val_bit:1;
+		u32 user_bit:1;
+		u32 underrun:1;
+		u32 rsvd1:20;
+	} cfg_regx;
+	struct {
+		u32 aud_en:1;
+		u32 layout:1;
+		u32 fmt:2;
+		u32 num_ch:3;
+		u32 set:1;
+		u32 flat:1;
+		u32 val_bit:1;
+		u32 user_bit:1;
+		u32 underrun:1;
+		u32 packet_mode:1;
+		u32 left_align:1;
+		u32 bogus_sample:1;
+		u32 dp_modei:1;
+		u32 rsvd:16;
+	} cfg_regx_v2;
+	u32 cfg_regval;
+};
+
+/**
+ * union aud_ch_status_0 - Audio Channel Status 0 Attributes
+ *
+ * @status_0_regx:individual register bits
+ * @status_0_regval:full register value
+ *
+ */
+union aud_ch_status_0 {
+	struct {
+		u32 ch_status:1;
+		u32 lpcm_id:1;
+		u32 cp_info:1;
+		u32 format:3;
+		u32 mode:2;
+		u32 ctg_code:8;
+		u32 src_num:4;
+		u32 ch_num:4;
+		u32 samp_freq:4;
+		u32 clk_acc:2;
+		u32 rsvd:2;
+	} status_0_regx;
+	u32 status_0_regval;
+};
+
+/**
+ * union aud_ch_status_1 - Audio Channel Status 1 Attributes
+ *
+ * @status_1_regx: individual register bits
+ * @status_1_regval: full register value
+ *
+ */
+union aud_ch_status_1 {
+	struct {
+		u32 max_wrd_len:1;
+		u32 wrd_len:3;
+		u32 rsvd:28;
+		} status_1_regx;
+	u32 status_1_regval;
+};
+
+/**
+ * union aud_hdmi_cts - CTS register
+ *
+ * @cts_regx: individual register bits
+ * @cts_regval: full register value
+ *
+ */
+union aud_hdmi_cts {
+	struct {
+		u32 cts_val:20;
+		u32 en_cts_prog:1;
+		u32 rsvd:11;
+	} cts_regx;
+	struct {
+		u32 cts_val:24;
+		u32 en_cts_prog:1;
+		u32 rsvd:7;
+	} cts_regx_v2;
+	u32 cts_regval;
+};
+
+/**
+ * union aud_hdmi_n_enable - N register
+ *
+ * @n_regx: individual register bits
+ * @n_regval: full register value
+ *
+ */
+union aud_hdmi_n_enable {
+	struct {
+		u32 n_val:20;
+		u32 en_n_prog:1;
+		u32 rsvd:11;
+	} n_regx;
+	struct {
+		u32 n_val:24;
+		u32 en_n_prog:1;
+		u32 rsvd:7;
+	} n_regx_v2;
+	u32 n_regval;
+};
+
+/**
+ * union aud_buf_config -  Audio Buffer configurations
+ *
+ * @buf_cfg_regx: individual register bits
+ * @buf_cfgval: full register value
+ *
+ */
+union aud_buf_config {
+	struct {
+		u32 fifo_width:8;
+		u32 rsvd0:8;
+		u32 aud_delay:8;
+		u32 rsvd1:8;
+	} buf_cfg_regx;
+	struct {
+		u32 audio_fifo_watermark:8;
+		u32 dma_fifo_watermark:3;
+		u32 rsvd0:5;
+		u32 aud_delay:8;
+		u32 rsvd1:8;
+	} buf_cfg_regx_v2;
+	u32 buf_cfgval;
+};
+
+/**
+ * union aud_buf_ch_swap - Audio Sample Swapping offset
+ *
+ * @buf_ch_swap_regx: individual register bits
+ * @buf_ch_swap_val: full register value
+ *
+ */
+union aud_buf_ch_swap {
+	struct {
+		u32 first_0:3;
+		u32 second_0:3;
+		u32 first_1:3;
+		u32 second_1:3;
+		u32 first_2:3;
+		u32 second_2:3;
+		u32 first_3:3;
+		u32 second_3:3;
+		u32 rsvd:8;
+	} buf_ch_swap_regx;
+	u32 buf_ch_swap_val;
+};
+
+/**
+ * union aud_buf_addr - Address for Audio Buffer
+ *
+ * @buf_addr_regx: individual register bits
+ * @buf_addr_val: full register value
+ *
+ */
+union aud_buf_addr {
+	struct {
+		u32 valid:1;
+		u32 intr_en:1;
+		u32 rsvd:4;
+		u32 addr:26;
+	} buf_addr_regx;
+	u32 buf_addr_val;
+};
+
+/**
+ * union aud_buf_len - Length of Audio Buffer
+ *
+ * @buf_len_regx: individual register bits
+ * @buf_len_val: full register value
+ *
+ */
+union aud_buf_len {
+	struct {
+		u32 buf_len:20;
+		u32 rsvd:12;
+	} buf_len_regx;
+	u32 buf_len_val;
+};
+
+/**
+ * union aud_ctrl_st - Audio Control State Register offset
+ *
+ * @ctrl_regx: individual register bits
+ * @ctrl_val: full register value
+ *
+ */
+union aud_ctrl_st {
+	struct {
+		u32 ram_addr:4;
+		u32 eld_ack:1;
+		u32 eld_addr:4;
+		u32 eld_buf_size:5;
+		u32 eld_valid:1;
+		u32 cp_ready:1;
+		u32 dip_freq:2;
+		u32 dip_idx:3;
+		u32 dip_en_sta:4;
+		u32 rsvd:7;
+	} ctrl_regx;
+	u32 ctrl_val;
+};
+
+/**
+ * union aud_info_frame1 - Audio HDMI Widget Data Island Packet offset
+ *
+ * @fr1_regx: individual register bits
+ * @fr1_val: full register value
+ *
+ */
+union aud_info_frame1 {
+	struct {
+		u32 pkt_type:8;
+		u32 ver_num:8;
+		u32 len:5;
+		u32 rsvd:11;
+	} fr1_regx;
+	u32 fr1_val;
+};
+
+/**
+ * union aud_info_frame2 - DIP frame 2
+ *
+ * @fr2_regx: individual register bits
+ * @fr2_val: full register value
+ *
+ */
+union aud_info_frame2 {
+	struct {
+		u32 chksum:8;
+		u32 chnl_cnt:3;
+		u32 rsvd0:1;
+		u32 coding_type:4;
+		u32 smpl_size:2;
+		u32 smpl_freq:3;
+		u32 rsvd1:3;
+		u32 format:8;
+	} fr2_regx;
+	u32 fr2_val;
+};
+
+/**
+ * union aud_info_frame3 - DIP frame 3
+ *
+ * @fr3_regx: individual register bits
+ * @fr3_val: full register value
+ *
+ */
+union aud_info_frame3 {
+	struct {
+		u32 chnl_alloc:8;
+		u32 rsvd0:3;
+		u32 lsv:4;
+		u32 dm_inh:1;
+		u32 rsvd1:16;
+	} fr3_regx;
+	u32 fr3_val;
+};
+
+enum hdmi_connector_status {
+	hdmi_connector_status_connected = 1,
+	hdmi_connector_status_disconnected = 2,
+	hdmi_connector_status_unknown = 3,
+};
+
+#define HDMI_AUDIO_UNDERRUN     (1UL<<31)
+#define HDMI_AUDIO_BUFFER_DONE  (1UL<<29)
+
+
+#define PORT_ENABLE			(1 << 31)
+#define SDVO_AUDIO_ENABLE	(1 << 6)
+
+enum had_caps_list {
+	HAD_GET_ELD = 1,
+	HAD_GET_DISPLAY_RATE,
+	HAD_SET_ENABLE_AUDIO,
+	HAD_SET_DISABLE_AUDIO,
+	HAD_SET_ENABLE_AUDIO_INT,
+	HAD_SET_DISABLE_AUDIO_INT,
+};
+
+enum had_event_type {
+	HAD_EVENT_HOT_PLUG = 1,
+	HAD_EVENT_HOT_UNPLUG,
+	HAD_EVENT_MODE_CHANGING,
+	HAD_EVENT_AUDIO_BUFFER_DONE,
+	HAD_EVENT_AUDIO_BUFFER_UNDERRUN,
+	HAD_EVENT_QUERY_IS_AUDIO_BUSY,
+	HAD_EVENT_QUERY_IS_AUDIO_SUSPENDED,
+};
+
+/*
+ * HDMI Display Controller Audio Interface
+ *
+ */
+typedef int (*had_event_call_back) (enum had_event_type event_type,
+		void *ctxt_info);
+
+struct hdmi_audio_registers_ops {
+	int (*hdmi_audio_get_register_base)(u32 **reg_base,
+			u32 *config_offset);
+	int (*hdmi_audio_read_register)(u32 reg_addr, u32 *data);
+	int (*hdmi_audio_write_register)(u32 reg_addr, u32 data);
+	int (*hdmi_audio_read_modify)(u32 reg_addr, u32 data,
+			u32 mask);
+};
+
+struct hdmi_audio_query_set_ops {
+	int (*hdmi_audio_get_caps)(enum had_caps_list query_element,
+			void *capabilties);
+	int (*hdmi_audio_set_caps)(enum had_caps_list set_element,
+			void *capabilties);
+};
+
+struct hdmi_audio_event {
+	int type;
+};
+
+struct snd_intel_had_interface {
+	const char *name;
+	int (*query)(void *had_data, struct hdmi_audio_event event);
+	int (*suspend)(void *had_data, struct hdmi_audio_event event);
+	int (*resume)(void *had_data);
+};
+
+bool mid_hdmi_audio_is_busy(void *dev);
+bool mid_hdmi_audio_suspend(void *dev);
+void mid_hdmi_audio_resume(void *dev);
+void mid_hdmi_audio_signal_event(enum had_event_type event);
+int mid_hdmi_audio_setup(
+	had_event_call_back audio_callbacks,
+	struct hdmi_audio_registers_ops *reg_ops,
+	struct hdmi_audio_query_set_ops *query_ops);
+int mid_hdmi_audio_register(
+	struct snd_intel_had_interface *driver,
+	void *had_data);
+
+#endif