// SPDX-License-Identifier: GPL-2.0+
//
// AMD Renoir ACP PCI Driver
//
//Copyright 2020 Advanced Micro Devices, Inc.

#include <linux/pci.h>
#include <linux/module.h>
#include <linux/io.h>
#include <linux/delay.h>
#include <linux/platform_device.h>
#include <linux/interrupt.h>
#include <linux/pm_runtime.h>

#include "rn_acp3x.h"

static int acp_power_gating;
module_param(acp_power_gating, int, 0644);
MODULE_PARM_DESC(acp_power_gating, "Enable acp power gating");

struct acp_dev_data {
	void __iomem *acp_base;
	struct resource *res;
	struct platform_device *pdev[ACP_DEVS];
};

static int rn_acp_power_on(void __iomem *acp_base)
{
	u32 val;
	int timeout;

	val = rn_readl(acp_base + ACP_PGFSM_STATUS);

	if (val == 0)
		return val;

	if ((val & ACP_PGFSM_STATUS_MASK) !=
				ACP_POWER_ON_IN_PROGRESS)
		rn_writel(ACP_PGFSM_CNTL_POWER_ON_MASK,
			  acp_base + ACP_PGFSM_CONTROL);
	timeout = 0;
	while (++timeout < 500) {
		val = rn_readl(acp_base + ACP_PGFSM_STATUS);
		if (!val)
			return 0;
		udelay(1);
	}
	return -ETIMEDOUT;
}

static int rn_acp_power_off(void __iomem *acp_base)
{
	u32 val;
	int timeout;

	rn_writel(ACP_PGFSM_CNTL_POWER_OFF_MASK,
		  acp_base + ACP_PGFSM_CONTROL);
	timeout = 0;
	while (++timeout < 500) {
		val = rn_readl(acp_base + ACP_PGFSM_STATUS);
		if ((val & ACP_PGFSM_STATUS_MASK) == ACP_POWERED_OFF)
			return 0;
		udelay(1);
	}
	return -ETIMEDOUT;
}

static int rn_acp_reset(void __iomem *acp_base)
{
	u32 val;
	int timeout;

	rn_writel(1, acp_base + ACP_SOFT_RESET);
	timeout = 0;
	while (++timeout < 500) {
		val = rn_readl(acp_base + ACP_SOFT_RESET);
		if (val & ACP_SOFT_RESET_SOFTRESET_AUDDONE_MASK)
			break;
		cpu_relax();
	}
	rn_writel(0, acp_base + ACP_SOFT_RESET);
	timeout = 0;
	while (++timeout < 500) {
		val = rn_readl(acp_base + ACP_SOFT_RESET);
		if (!val)
			return 0;
		cpu_relax();
	}
	return -ETIMEDOUT;
}

static void rn_acp_enable_interrupts(void __iomem *acp_base)
{
	u32 ext_intr_ctrl;

	rn_writel(0x01, acp_base + ACP_EXTERNAL_INTR_ENB);
	ext_intr_ctrl = rn_readl(acp_base + ACP_EXTERNAL_INTR_CNTL);
	ext_intr_ctrl |= ACP_ERROR_MASK;
	rn_writel(ext_intr_ctrl, acp_base + ACP_EXTERNAL_INTR_CNTL);
}

static void rn_acp_disable_interrupts(void __iomem *acp_base)
{
	rn_writel(ACP_EXT_INTR_STAT_CLEAR_MASK, acp_base +
		  ACP_EXTERNAL_INTR_STAT);
	rn_writel(0x00, acp_base + ACP_EXTERNAL_INTR_ENB);
}

static int rn_acp_init(void __iomem *acp_base)
{
	int ret;

	/* power on */
	ret = rn_acp_power_on(acp_base);
	if (ret) {
		pr_err("ACP power on failed\n");
		return ret;
	}
	rn_writel(0x01, acp_base + ACP_CONTROL);
	/* Reset */
	ret = rn_acp_reset(acp_base);
	if (ret) {
		pr_err("ACP reset failed\n");
		return ret;
	}
	rn_writel(0x03, acp_base + ACP_CLKMUX_SEL);
	rn_acp_enable_interrupts(acp_base);
	return 0;
}

static int rn_acp_deinit(void __iomem *acp_base)
{
	int ret;

	rn_acp_disable_interrupts(acp_base);
	/* Reset */
	ret = rn_acp_reset(acp_base);
	if (ret) {
		pr_err("ACP reset failed\n");
		return ret;
	}
	rn_writel(0x00, acp_base + ACP_CLKMUX_SEL);
	rn_writel(0x00, acp_base + ACP_CONTROL);
	/* power off */
	if (acp_power_gating) {
		ret = rn_acp_power_off(acp_base);
		if (ret) {
			pr_err("ACP power off failed\n");
			return ret;
		}
	}
	return 0;
}

static int snd_rn_acp_probe(struct pci_dev *pci,
			    const struct pci_device_id *pci_id)
{
	struct acp_dev_data *adata;
	struct platform_device_info pdevinfo[ACP_DEVS];
	unsigned int irqflags;
	int ret, index;
	u32 addr;

	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");
		goto disable_pci;
	}

	adata = devm_kzalloc(&pci->dev, sizeof(struct acp_dev_data),
			     GFP_KERNEL);
	if (!adata) {
		ret = -ENOMEM;
		goto release_regions;
	}

	/* check for msi interrupt support */
	ret = pci_enable_msi(pci);
	if (ret)
		/* msi is not enabled */
		irqflags = IRQF_SHARED;
	else
		/* msi is enabled */
		irqflags = 0;

	addr = pci_resource_start(pci, 0);
	adata->acp_base = devm_ioremap(&pci->dev, addr,
				       pci_resource_len(pci, 0));
	if (!adata->acp_base) {
		ret = -ENOMEM;
		goto disable_msi;
	}
	pci_set_master(pci);
	pci_set_drvdata(pci, adata);
	ret = rn_acp_init(adata->acp_base);
	if (ret)
		goto disable_msi;

	adata->res = devm_kzalloc(&pci->dev,
				  sizeof(struct resource) * 2,
				  GFP_KERNEL);
	if (!adata->res) {
		ret = -ENOMEM;
		goto de_init;
	}

	adata->res[0].name = "acp_pdm_iomem";
	adata->res[0].flags = IORESOURCE_MEM;
	adata->res[0].start = addr;
	adata->res[0].end = addr + (ACP_REG_END - ACP_REG_START);
	adata->res[1].name = "acp_pdm_irq";
	adata->res[1].flags = IORESOURCE_IRQ;
	adata->res[1].start = pci->irq;
	adata->res[1].end = pci->irq;

	memset(&pdevinfo, 0, sizeof(pdevinfo));
	pdevinfo[0].name = "acp_rn_pdm_dma";
	pdevinfo[0].id = 0;
	pdevinfo[0].parent = &pci->dev;
	pdevinfo[0].num_res = 2;
	pdevinfo[0].res = adata->res;
	pdevinfo[0].data = &irqflags;
	pdevinfo[0].size_data = sizeof(irqflags);

	pdevinfo[1].name = "dmic-codec";
	pdevinfo[1].id = 0;
	pdevinfo[1].parent = &pci->dev;
	pdevinfo[2].name = "acp_pdm_mach";
	pdevinfo[2].id = 0;
	pdevinfo[2].parent = &pci->dev;
	for (index = 0; index < ACP_DEVS; index++) {
		adata->pdev[index] =
				platform_device_register_full(&pdevinfo[index]);
		if (IS_ERR(adata->pdev[index])) {
			dev_err(&pci->dev, "cannot register %s device\n",
				pdevinfo[index].name);
			ret = PTR_ERR(adata->pdev[index]);
			goto unregister_devs;
		}
	}
	pm_runtime_set_autosuspend_delay(&pci->dev, ACP_SUSPEND_DELAY_MS);
	pm_runtime_use_autosuspend(&pci->dev);
	pm_runtime_put_noidle(&pci->dev);
	pm_runtime_allow(&pci->dev);
	return 0;

unregister_devs:
	for (index = 0; index < ACP_DEVS; index++)
		platform_device_unregister(adata->pdev[index]);
de_init:
	if (rn_acp_deinit(adata->acp_base))
		dev_err(&pci->dev, "ACP de-init failed\n");
disable_msi:
	pci_disable_msi(pci);
release_regions:
	pci_release_regions(pci);
disable_pci:
	pci_disable_device(pci);

	return ret;
}

static int snd_rn_acp_suspend(struct device *dev)
{
	int ret;
	struct acp_dev_data *adata;

	adata = dev_get_drvdata(dev);
	ret = rn_acp_deinit(adata->acp_base);
	if (ret)
		dev_err(dev, "ACP de-init failed\n");
	else
		dev_dbg(dev, "ACP de-initialized\n");

	return ret;
}

static int snd_rn_acp_resume(struct device *dev)
{
	int ret;
	struct acp_dev_data *adata;

	adata = dev_get_drvdata(dev);
	ret = rn_acp_init(adata->acp_base);
	if (ret) {
		dev_err(dev, "ACP init failed\n");
		return ret;
	}
	return 0;
}

static const struct dev_pm_ops rn_acp_pm = {
	.runtime_suspend = snd_rn_acp_suspend,
	.runtime_resume =  snd_rn_acp_resume,
	.suspend = snd_rn_acp_suspend,
	.resume =	snd_rn_acp_resume,
};

static void snd_rn_acp_remove(struct pci_dev *pci)
{
	struct acp_dev_data *adata;
	int ret, index;

	adata = pci_get_drvdata(pci);
	for (index = 0; index < ACP_DEVS; index++)
		platform_device_unregister(adata->pdev[index]);
	ret = rn_acp_deinit(adata->acp_base);
	if (ret)
		dev_err(&pci->dev, "ACP de-init failed\n");
	pm_runtime_forbid(&pci->dev);
	pm_runtime_get_noresume(&pci->dev);
	pci_disable_msi(pci);
	pci_release_regions(pci);
	pci_disable_device(pci);
}

static const struct pci_device_id snd_rn_acp_ids[] = {
	{ PCI_DEVICE(PCI_VENDOR_ID_AMD, ACP_DEVICE_ID),
	.class = PCI_CLASS_MULTIMEDIA_OTHER << 8,
	.class_mask = 0xffffff },
	{ 0, },
};
MODULE_DEVICE_TABLE(pci, snd_rn_acp_ids);

static struct pci_driver rn_acp_driver  = {
	.name = KBUILD_MODNAME,
	.id_table = snd_rn_acp_ids,
	.probe = snd_rn_acp_probe,
	.remove = snd_rn_acp_remove,
	.driver = {
		.pm = &rn_acp_pm,
	}
};

module_pci_driver(rn_acp_driver);

MODULE_AUTHOR("Vijendar.Mukunda@amd.com");
MODULE_DESCRIPTION("AMD ACP Renoir PCI driver");
MODULE_LICENSE("GPL v2");