ALSA: hda: move parts of NHLT code to new module

Move parts of the code outside of the Skylake driver to help detect
the presence of DMICs (which are not supported by the HDaudio legacy
driver).

No functionality change (except for the removal of useless OR
operations), only indentation and checkpatch fixes, making sure
that the code compiles without ACPI and fixing an ACPI leak

Signed-off-by: Pierre-Louis Bossart <pierre-louis.bossart@linux.intel.com>
Signed-off-by: Takashi Iwai <tiwai@suse.de>

include/sound/intel-nhlt.h

@@ -1,18 +1,17 @@
 /* SPDX-License-Identifier: GPL-2.0-only */
 /*
- *  skl-nhlt.h - Intel HDA Platform NHLT header
+ *  intel-nhlt.h - Intel HDA Platform NHLT header
  *
- *  Copyright (C) 2015 Intel Corp
+ *  Copyright (c) 2015-2019 Intel Corporation
- *  Author: Sanjiv Kumar <sanjiv.kumar@intel.com>
- *  ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
- *
- * ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
  */
-#ifndef __SKL_NHLT_H__
+
-#define __SKL_NHLT_H__
+#ifndef __INTEL_NHLT_H__
+#define __INTEL_NHLT_H__
 
 #include <linux/acpi.h>
 
+#if IS_ENABLED(CONFIG_ACPI) && IS_ENABLED(CONFIG_SND_INTEL_NHLT)
+
 struct wav_fmt {
 	u16 fmt_tag;
 	u16 channels;
@@ -116,4 +115,30 @@ enum {
 	NHLT_MIC_ARRAY_VENDOR_DEFINED = 0xf,
 };
 
+struct nhlt_acpi_table *intel_nhlt_init(struct device *dev);
+
+void intel_nhlt_free(struct nhlt_acpi_table *addr);
+
+int intel_nhlt_get_dmic_geo(struct device *dev, struct nhlt_acpi_table *nhlt);
+
+#else
+
+struct nhlt_acpi_table;
+
+static inline struct nhlt_acpi_table *intel_nhlt_init(struct device *dev)
+{
+	return NULL;
+}
+
+static inline void intel_nhlt_free(struct nhlt_acpi_table *addr)
+{
+}
+
+static inline int intel_nhlt_get_dmic_geo(struct device *dev,
+					  struct nhlt_acpi_table *nhlt)
+{
+	return 0;
+}
+#endif
+
 #endif

sound/hda/Kconfig

@@ -29,3 +29,8 @@ config SND_HDA_PREALLOC_SIZE
 
 	  Note that the pre-allocation size can be changed dynamically
 	  via a proc file (/proc/asound/card*/pcm*/sub*/prealloc), too.
+
+config SND_INTEL_NHLT
+	tristate
+	# this config should be selected only for Intel ACPI platforms.
+	# A fallback is provided so that the code compiles in all cases.

sound/hda/Makefile

@@ -13,3 +13,6 @@ obj-$(CONFIG_SND_HDA_CORE) += snd-hda-core.o
 
 #extended hda
 obj-$(CONFIG_SND_HDA_EXT_CORE) += ext/
+
+snd-intel-nhlt-objs := intel-nhlt.o
+obj-$(CONFIG_SND_INTEL_NHLT) += snd-intel-nhlt.o

sound/hda/intel-nhlt.c

@@ -0,0 +1,103 @@
+// SPDX-License-Identifier: GPL-2.0
+// Copyright (c) 2015-2019 Intel Corporation
+
+#include <linux/acpi.h>
+#include <sound/intel-nhlt.h>
+
+#define NHLT_ACPI_HEADER_SIG	"NHLT"
+
+/* Unique identification for getting NHLT blobs */
+static guid_t osc_guid =
+	GUID_INIT(0xA69F886E, 0x6CEB, 0x4594,
+		  0xA4, 0x1F, 0x7B, 0x5D, 0xCE, 0x24, 0xC5, 0x53);
+
+struct nhlt_acpi_table *intel_nhlt_init(struct device *dev)
+{
+	acpi_handle handle;
+	union acpi_object *obj;
+	struct nhlt_resource_desc *nhlt_ptr;
+	struct nhlt_acpi_table *nhlt_table = NULL;
+
+	handle = ACPI_HANDLE(dev);
+	if (!handle) {
+		dev_err(dev, "Didn't find ACPI_HANDLE\n");
+		return NULL;
+	}
+
+	obj = acpi_evaluate_dsm(handle, &osc_guid, 1, 1, NULL);
+
+	if (!obj)
+		return NULL;
+
+	if (obj->type != ACPI_TYPE_BUFFER) {
+		dev_dbg(dev, "No NHLT table found\n");
+		ACPI_FREE(obj);
+		return NULL;
+	}
+
+	nhlt_ptr = (struct nhlt_resource_desc  *)obj->buffer.pointer;
+	if (nhlt_ptr->length)
+		nhlt_table = (struct nhlt_acpi_table *)
+			memremap(nhlt_ptr->min_addr, nhlt_ptr->length,
+				 MEMREMAP_WB);
+	ACPI_FREE(obj);
+	if (nhlt_table &&
+	    (strncmp(nhlt_table->header.signature,
+		     NHLT_ACPI_HEADER_SIG,
+		     strlen(NHLT_ACPI_HEADER_SIG)) != 0)) {
+		memunmap(nhlt_table);
+		dev_err(dev, "NHLT ACPI header signature incorrect\n");
+		return NULL;
+	}
+	return nhlt_table;
+}
+EXPORT_SYMBOL_GPL(intel_nhlt_init);
+
+void intel_nhlt_free(struct nhlt_acpi_table *nhlt)
+{
+	memunmap((void *)nhlt);
+}
+EXPORT_SYMBOL_GPL(intel_nhlt_free);
+
+int intel_nhlt_get_dmic_geo(struct device *dev, struct nhlt_acpi_table *nhlt)
+{
+	struct nhlt_endpoint *epnt;
+	struct nhlt_dmic_array_config *cfg;
+	unsigned int dmic_geo = 0;
+	u8 j;
+
+	if (!nhlt)
+		return 0;
+
+	epnt = (struct nhlt_endpoint *)nhlt->desc;
+
+	for (j = 0; j < nhlt->endpoint_count; j++) {
+		if (epnt->linktype == NHLT_LINK_DMIC) {
+			cfg = (struct nhlt_dmic_array_config  *)
+					(epnt->config.caps);
+			switch (cfg->array_type) {
+			case NHLT_MIC_ARRAY_2CH_SMALL:
+			case NHLT_MIC_ARRAY_2CH_BIG:
+				dmic_geo = MIC_ARRAY_2CH;
+				break;
+
+			case NHLT_MIC_ARRAY_4CH_1ST_GEOM:
+			case NHLT_MIC_ARRAY_4CH_L_SHAPED:
+			case NHLT_MIC_ARRAY_4CH_2ND_GEOM:
+				dmic_geo = MIC_ARRAY_4CH;
+				break;
+
+			default:
+				dev_warn(dev, "undefined DMIC array_type 0x%0x\n",
+					 cfg->array_type);
+			}
+		}
+		epnt = (struct nhlt_endpoint *)((u8 *)epnt + epnt->length);
+	}
+
+	return dmic_geo;
+}
+EXPORT_SYMBOL_GPL(intel_nhlt_get_dmic_geo);
+
+MODULE_LICENSE("GPL v2");
+MODULE_DESCRIPTION("Intel NHLT driver");