ASoC: amd: acp: Add generic PCI driver module for ACP device

Audio Co-processor or ACP IP block on AMD's SOC is connected via
PCI bus interface, hence needs to be register as a PCI device. We
have same PCI device ID across multiple SOC's but with different
revision id for PCI hw. Add a generic PCI driver module for ACP
that registers ACP as a PCI device and also register a platform
device based on pci revision id. Any SOC's specific configuration
for ACP block will be done in platform driver probe. We have added
an initial support for ACP revision id 3 or ACP3X device.
Signed-off-by: Ajit Kumar Pandey <AjitKumar.Pandey@amd.com>
Link: https://lore.kernel.org/r/20220117115854.455995-4-AjitKumar.Pandey@amd.comSigned-off-by: Mark Brown <broonie@kernel.org>

sound/soc/amd/acp/Kconfig

@@ -25,6 +25,12 @@ config SND_SOC_AMD_ACP_PCM
 	tristate
 	select SND_SOC_ACPI if ACPI
 
+config SND_SOC_AMD_ACP_PCI
+	tristate "AMD ACP PCI Driver Support"
+	depends on X86 && PCI
+	help
+	  This options enables generic PCI driver for ACP device.
+
 config SND_AMD_ASOC_RENOIR
 	tristate "AMD ACP ASOC Renoir Support"
 	select SND_SOC_AMD_ACP_PCM

sound/soc/amd/acp/Makefile

@@ -8,6 +8,7 @@
 snd-acp-pcm-objs     := acp-platform.o
 snd-acp-i2s-objs     := acp-i2s.o
 snd-acp-pdm-objs     := acp-pdm.o
+snd-acp-pci-objs     := acp-pci.o
 
 #platform specific driver
 snd-acp-renoir-objs     := acp-renoir.o
@@ -20,6 +21,7 @@ snd-acp-sof-mach-objs     := acp-sof-mach.o
 obj-$(CONFIG_SND_SOC_AMD_ACP_PCM) += snd-acp-pcm.o
 obj-$(CONFIG_SND_SOC_AMD_ACP_I2S) += snd-acp-i2s.o
 obj-$(CONFIG_SND_SOC_AMD_ACP_PDM) += snd-acp-pdm.o
+obj-$(CONFIG_SND_SOC_AMD_ACP_PCI) += snd-acp-pci.o
 
 obj-$(CONFIG_SND_AMD_ASOC_RENOIR) += snd-acp-renoir.o
 

sound/soc/amd/acp/acp-pci.c

+// SPDX-License-Identifier: (GPL-2.0-only OR BSD-3-Clause)
+//
+// This file is provided under a dual BSD/GPLv2 license. When using or
+// redistributing this file, you may do so under either license.
+//
+// Copyright(c) 2022 Advanced Micro Devices, Inc. All rights reserved.
+//
+// Authors: Ajit Kumar Pandey <AjitKumar.Pandey@amd.com>
+
+/*
+ * Generic PCI interface for ACP device
+ */
+
+#include <linux/delay.h>
+#include <linux/interrupt.h>
+#include <linux/pci.h>
+#include <linux/platform_device.h>
+#include <linux/pm_runtime.h>
+
+#include "amd.h"
+#include "../mach-config.h"
+
+#define DRV_NAME "acp_pci"
+
+#define ACP3x_REG_START	0x1240000
+#define ACP3x_REG_END	0x125C000
+
+static struct platform_device *dmic_dev;
+static struct platform_device *pdev;
+
+static const struct resource acp3x_res[] = {
+	{
+		.start = 0,
+		.end = ACP3x_REG_END - ACP3x_REG_START,
+		.name = "acp_mem",
+		.flags = IORESOURCE_MEM,
+	},
+	{
+		.start = 0,
+		.end = 0,
+		.name = "acp_dai_irq",
+		.flags = IORESOURCE_IRQ,
+	},
+};
+
+static int acp_pci_probe(struct pci_dev *pci, const struct pci_device_id *pci_id)
+{
+	struct platform_device_info pdevinfo;
+	struct device *dev = &pci->dev;
+	const struct resource *res_acp;
+	struct acp_chip_info *chip;
+	struct resource *res;
+	unsigned int flag, addr, num_res, i;
+	int ret;
+
+	flag = snd_amd_acp_find_config(pci);
+	if (flag != FLAG_AMD_LEGACY)
+		return -ENODEV;
+
+	chip = devm_kzalloc(&pci->dev, sizeof(*chip), GFP_KERNEL);
+	if (!chip)
+		return -ENOMEM;
+
+	if (pci_enable_device(pci)) {
+		dev_err(&pci->dev, "pci_enable_device failed\n");
+		return -ENODEV;
+	}
+
+	ret = pci_request_regions(pci, "AMD ACP3x audio");
+	if (ret < 0) {
+		dev_err(&pci->dev, "pci_request_regions failed\n");
+		return -ENOMEM;
+	}
+
+	pci_set_master(pci);
+
+	switch (pci->revision) {
+	case 0x01:
+		res_acp = acp3x_res;
+		num_res = ARRAY_SIZE(acp3x_res);
+		chip->name = "acp_asoc_renoir";
+		chip->acp_rev = ACP3X_DEV;
+		break;
+	default:
+		dev_err(dev, "Unsupported device revision:0x%x\n", pci->revision);
+		return -EINVAL;
+	}
+
+	dmic_dev = platform_device_register_data(dev, "dmic-codec", PLATFORM_DEVID_NONE, NULL, 0);
+	if (IS_ERR(dmic_dev)) {
+		dev_err(dev, "failed to create DMIC device\n");
+		return PTR_ERR(dmic_dev);
+	}
+
+	addr = pci_resource_start(pci, 0);
+	chip->base = devm_ioremap(&pci->dev, addr, pci_resource_len(pci, 0));
+
+	res = devm_kzalloc(&pci->dev, sizeof(struct resource) * num_res, GFP_KERNEL);
+	if (!res) {
+		platform_device_unregister(dmic_dev);
+		return -ENOMEM;
+	}
+
+	for (i = 0; i < num_res; i++, res_acp++) {
+		res[i].name = res_acp->name;
+		res[i].flags = res_acp->flags;
+		res[i].start = addr + res_acp->start;
+		res[i].end = addr + res_acp->end;
+		if (res_acp->flags == IORESOURCE_IRQ) {
+			res[i].start = pci->irq;
+			res[i].end = res[i].start;
+		}
+	}
+
+	memset(&pdevinfo, 0, sizeof(pdevinfo));
+
+	pdevinfo.name = chip->name;
+	pdevinfo.id = 0;
+	pdevinfo.parent = &pci->dev;
+	pdevinfo.num_res = num_res;
+	pdevinfo.res = &res[0];
+	pdevinfo.data = chip;
+	pdevinfo.size_data = sizeof(*chip);
+
+	pdev = platform_device_register_full(&pdevinfo);
+	if (IS_ERR(pdev)) {
+		dev_err(&pci->dev, "cannot register %s device\n", pdevinfo.name);
+		platform_device_unregister(dmic_dev);
+		ret = PTR_ERR(pdev);
+	}
+
+	return ret;
+};
+
+static void acp_pci_remove(struct pci_dev *pci)
+{
+	if (dmic_dev)
+		platform_device_unregister(dmic_dev);
+	if (pdev)
+		platform_device_unregister(pdev);
+}
+
+/* PCI IDs */
+static const struct pci_device_id acp_pci_ids[] = {
+	{ PCI_DEVICE(PCI_VENDOR_ID_AMD, ACP_PCI_DEV_ID)},
+	{ 0, }
+};
+MODULE_DEVICE_TABLE(pci, acp_pci_ids);
+
+/* pci_driver definition */
+static struct pci_driver snd_amd_acp_pci_driver = {
+	.name = KBUILD_MODNAME,
+	.id_table = acp_pci_ids,
+	.probe = acp_pci_probe,
+	.remove = acp_pci_remove,
+};
+module_pci_driver(snd_amd_acp_pci_driver);
+
+MODULE_LICENSE("Dual BSD/GPL");
+MODULE_ALIAS(DRV_NAME);

sound/soc/amd/acp/amd.h

@@ -12,9 +12,14 @@
 #define __AMD_ACP_H
 
 #include <sound/pcm.h>
+#include <sound/soc.h>
 #include <sound/soc-acpi.h>
+#include <sound/soc-dai.h>
+
 #include "chip_offset_byte.h"
 
+#define ACP3X_DEV			3
+
 #define I2S_SP_INSTANCE			0x00
 #define I2S_BT_INSTANCE			0x01
 #define DMIC_INSTANCE			0x02
@@ -70,6 +75,12 @@
 
 #define ACP_MAX_STREAM			6
 
+struct acp_chip_info {
+	char *name;		/* Platform name */
+	unsigned int acp_rev;	/* ACP Revision id */
+	void __iomem *base;	/* ACP memory PCI base */
+};
+
 struct acp_stream {
 	struct snd_pcm_substream *substream;
 	int irq_bit;
@@ -106,6 +117,9 @@ int acp_platform_unregister(struct device *dev);
 
 int acp_machine_select(struct acp_dev_data *adata);
 
+/* Machine configuration */
+int snd_amd_acp_find_config(struct pci_dev *pci);
+
 static inline u64 acp_get_byte_count(struct acp_dev_data *adata, int dai_id, int direction)
 {
 	u64 byte_count, low = 0, high = 0;

sound/soc/amd/mach-config.h

@@ -14,6 +14,7 @@
 
 #define FLAG_AMD_SOF			BIT(1)
 #define FLAG_AMD_SOF_ONLY_DMIC		BIT(2)
+#define FLAG_AMD_LEGACY			BIT(3)
 
 #define ACP_PCI_DEV_ID			0x15E2