[v3] i2c:amd I2C Driver based on PCI Interface for upcoming, platform

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State New
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  • [v3] i2c:amd I2C Driver based on PCI Interface for upcoming, platform
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Commit Message

Shah, Nehal-bakulchandra Sept. 12, 2018, 10:54 a.m.
From: Nehal-bakulchandra Shah <Nehal-bakulchandra.Shah@amd.com>

This contains two drivers.
1)i2c-amd-platdrv: This is based on I2C framework of
linux kernel. So any i2c read write call or commands
to this driver is routed to PCI Interface driver.
2) i2c-amd-platdrv: This driver is responsible to
talk with Mp2 and does all C2P/P2C communication
or reading/writing from DRAM in case of more
data.


Reviewed-by: S-k, Shyam-sundar <Shyam-sundar.S-k@amd.com>
Reviewed-by: Sandeep Singh <sandeep.singh@amd.com>
Signed-off-by: Nehal-bakulchandra Shah <Nehal-bakulchandra.Shah@amd.com>
---
Changes since v1:(https://www.spinics.net/lists/linux-i2c/msg34650.html)
-> Add fix for IOMMU
-> Add depedency of ACPI
-> Add locks to avoid the crash

Changes since v2:(https://patchwork.ozlabs.org/patch/961270/)

-> fix for review comments
-> fix for more than 32 bytes write issue


 drivers/i2c/busses/Kconfig           |  10 +
 drivers/i2c/busses/Makefile          |   2 +
 drivers/i2c/busses/i2c-amd-pci-mp2.c | 580 +++++++++++++++++++++++++++++++++++
 drivers/i2c/busses/i2c-amd-pci-mp2.h | 196 ++++++++++++
 drivers/i2c/busses/i2c-amd-platdrv.c | 277 +++++++++++++++++
 5 files changed, 1065 insertions(+)
 create mode 100644 drivers/i2c/busses/i2c-amd-pci-mp2.c
 create mode 100644 drivers/i2c/busses/i2c-amd-pci-mp2.h
 create mode 100644 drivers/i2c/busses/i2c-amd-platdrv.c

Comments

Kai-Heng Feng Sept. 17, 2018, 8:19 a.m. | #1
at 18:54, Shah, Nehal-bakulchandra <Nehal-bakulchandra.Shah@amd.com> wrote:

> From: Nehal-bakulchandra Shah <Nehal-bakulchandra.Shah@amd.com>
>
> This contains two drivers.
> 1)i2c-amd-platdrv: This is based on I2C framework of
> linux kernel. So any i2c read write call or commands
> to this driver is routed to PCI Interface driver.
> 2) i2c-amd-platdrv: This driver is responsible to
> talk with Mp2 and does all C2P/P2C communication
> or reading/writing from DRAM in case of more
> data.
>
>
> Reviewed-by: S-k, Shyam-sundar <Shyam-sundar.S-k@amd.com>
> Reviewed-by: Sandeep Singh <sandeep.singh@amd.com>
> Signed-off-by: Nehal-bakulchandra Shah <Nehal-bakulchandra.Shah@amd.com>

The I2C touchpad on Latitude 5495 works with this patch.

Tested-by: Kai-Heng Feng <kai.heng.feng@canonical.com>

> ---
> Changes since v1:(https://www.spinics.net/lists/linux-i2c/msg34650.html)
> -> Add fix for IOMMU
> -> Add depedency of ACPI
> -> Add locks to avoid the crash
>
> Changes since v2:(https://patchwork.ozlabs.org/patch/961270/)
>
> -> fix for review comments
> -> fix for more than 32 bytes write issue
>
>
>  drivers/i2c/busses/Kconfig           |  10 +
>  drivers/i2c/busses/Makefile          |   2 +
>  drivers/i2c/busses/i2c-amd-pci-mp2.c | 580 +++++++++++++++++++++++++++++++++++
>  drivers/i2c/busses/i2c-amd-pci-mp2.h | 196 ++++++++++++
>  drivers/i2c/busses/i2c-amd-platdrv.c | 277 +++++++++++++++++
>  5 files changed, 1065 insertions(+)
>  create mode 100644 drivers/i2c/busses/i2c-amd-pci-mp2.c
>  create mode 100644 drivers/i2c/busses/i2c-amd-pci-mp2.h
>  create mode 100644 drivers/i2c/busses/i2c-amd-platdrv.c
>
> diff --git a/drivers/i2c/busses/Kconfig b/drivers/i2c/busses/Kconfig
> index 8d21b98..ff68424 100644
> --- a/drivers/i2c/busses/Kconfig
> +++ b/drivers/i2c/busses/Kconfig
> @@ -77,6 +77,16 @@ config I2C_AMD8111
>  	  This driver can also be built as a module.  If so, the module
>  	  will be called i2c-amd8111.
>
> +config I2C_AMD_MP2
> +	tristate "AMD MP2"
> +	depends on ACPI && PCI
> +	help
> +	  If you say yes to this option, support will be included for mp2
> +	  I2C interface.
> +
> +	  This driver can also be built as a module.  If so, the module
> +	  will be called i2c-amd-platdrv.
> +
>  config I2C_HIX5HD2
>  	tristate "Hix5hd2 high-speed I2C driver"
>  	depends on ARCH_HISI || ARCH_HIX5HD2 || COMPILE_TEST
> diff --git a/drivers/i2c/busses/Makefile b/drivers/i2c/busses/Makefile
> index 189e34b..b01e46b 100644
> --- a/drivers/i2c/busses/Makefile
> +++ b/drivers/i2c/busses/Makefile
> @@ -113,6 +113,8 @@ obj-$(CONFIG_I2C_XLR)		+= i2c-xlr.o
>  obj-$(CONFIG_I2C_XLP9XX)	+= i2c-xlp9xx.o
>  obj-$(CONFIG_I2C_RCAR)		+= i2c-rcar.o
>  obj-$(CONFIG_I2C_ZX2967)	+= i2c-zx2967.o
> +obj-$(CONFIG_I2C_AMD_MP2)   	+= i2c-amd-pci-mp2.o
> +obj-$(CONFIG_I2C_AMD_MP2)   	+= i2c-amd-platdrv.o
>
>  # External I2C/SMBus adapter drivers
>  obj-$(CONFIG_I2C_DIOLAN_U2C)	+= i2c-diolan-u2c.o
> diff --git a/drivers/i2c/busses/i2c-amd-pci-mp2.c  
> b/drivers/i2c/busses/i2c-amd-pci-mp2.c
> new file mode 100644
> index 0000000..984314c
> --- /dev/null
> +++ b/drivers/i2c/busses/i2c-amd-pci-mp2.c
> @@ -0,0 +1,580 @@
> +// SPDX-License-Identifier: GPL-2.0
> +/*
> + * Copyright (C) 2018 Advanced Micro Devices, Inc. All Rights Reserved.
> + *
> + *
> + * Author: Shyam Sundar S K <Shyam-sundar.S-k@amd.com>
> + * AMD PCIe MP2 Communication Driver
> + */
> +
> +#include <linux/debugfs.h>
> +#include <linux/interrupt.h>
> +#include <linux/module.h>
> +#include <linux/pci.h>
> +#include <linux/slab.h>
> +
> +#include "i2c-amd-pci-mp2.h"
> +
> +#define DRIVER_NAME	"pcie_mp2_amd"
> +#define DRIVER_DESC	"AMD(R) PCI-E MP2 Communication Driver"
> +#define DRIVER_VER	"1.0"
> +
> +MODULE_DESCRIPTION(DRIVER_DESC);
> +MODULE_VERSION(DRIVER_VER);
> +MODULE_LICENSE("Dual BSD/GPL");
> +MODULE_AUTHOR("Shyam Sundar S K <Shyam-sundar.S-k@amd.com>");
> +
> +static const struct file_operations amd_mp2_debugfs_info;
> +static struct dentry *debugfs_dir;
> +
> +int amd_mp2_connect(struct pci_dev *dev, struct i2c_config i2c_cfg)
> +{
> +	struct amd_mp2_dev *privdata = pci_get_drvdata(dev);
> +	union i2c_cmd_base i2c_cmd_base;
> +	unsigned  long  flags;
> +
> +	raw_spin_lock_irqsave(&privdata->lock, flags);
> +	dev_dbg(ndev_dev(privdata), "%s addr: %x id: %d\n", __func__,
> +		i2c_cfg.dev_addr, i2c_cfg.bus_id);
> +
> +	i2c_cmd_base.ul = 0;
> +	i2c_cmd_base.s.i2c_cmd = i2c_enable;
> +	i2c_cmd_base.s.bus_id = i2c_cfg.bus_id;
> +	i2c_cmd_base.s.i2c_speed = i2c_cfg.i2c_speed;
> +
> +	if (i2c_cmd_base.s.bus_id == i2c_bus_1) {
> +		writel(i2c_cmd_base.ul, privdata->mmio + AMD_C2P_MSG1);
> +	} else if (i2c_cmd_base.s.bus_id == i2c_bus_0) {
> +		writel(i2c_cmd_base.ul, privdata->mmio + AMD_C2P_MSG0);
> +	} else {
> +		dev_err(ndev_dev(privdata), "%s Invalid bus id\n", __func__);
> +		return -EINVAL;
> +	}
> +	raw_spin_unlock_irqrestore(&privdata->lock, flags);
> +	return 0;
> +}
> +EXPORT_SYMBOL_GPL(amd_mp2_connect);
> +
> +int amd_mp2_read(struct pci_dev *dev, struct i2c_config i2c_cfg)
> +{
> +	struct amd_mp2_dev *privdata = pci_get_drvdata(dev);
> +	union i2c_cmd_base i2c_cmd_base;
> +
> +	dev_dbg(ndev_dev(privdata), "%s addr: %x id: %d\n", __func__,
> +		i2c_cfg.dev_addr, i2c_cfg.bus_id);
> +
> +	privdata->requested = true;
> +	i2c_cmd_base.ul = 0;
> +	i2c_cmd_base.s.i2c_cmd = i2c_read;
> +	i2c_cmd_base.s.dev_addr = i2c_cfg.dev_addr;
> +	i2c_cmd_base.s.length = i2c_cfg.length;
> +	i2c_cmd_base.s.bus_id = i2c_cfg.bus_id;
> +
> +	if (i2c_cfg.length <= 32) {
> +		i2c_cmd_base.s.mem_type = use_c2pmsg;
> +		privdata->eventval.buf = (u32 *)i2c_cfg.read_buf;
> +		if (!privdata->eventval.buf) {
> +			dev_err(ndev_dev(privdata), "%s no mem for buf received\n",
> +				__func__);
> +			return -ENOMEM;
> +		}
> +	} else {
> +		i2c_cmd_base.s.mem_type = use_dram;
> +		privdata->i2c_cfg.phy_addr = i2c_cfg.phy_addr;
> +		privdata->i2c_cfg.read_buf = i2c_cfg.read_buf;
> +		write64((u64)privdata->i2c_cfg.phy_addr,
> +			privdata->mmio + AMD_C2P_MSG2);
> +	}
> +
> +	switch (i2c_cfg.i2c_speed) {
> +	case 0:
> +		i2c_cmd_base.s.i2c_speed = speed100k;
> +		break;
> +	case 1:
> +		i2c_cmd_base.s.i2c_speed = speed400k;
> +		break;
> +	case 2:
> +		i2c_cmd_base.s.i2c_speed = speed1000k;
> +		break;
> +	case 3:
> +		i2c_cmd_base.s.i2c_speed = speed1400k;
> +		break;
> +	case 4:
> +		i2c_cmd_base.s.i2c_speed = speed3400k;
> +		break;
> +	default:
> +		dev_err(ndev_dev(privdata), "Invalid ConnectionSpeed\n");
> +	}
> +
> +	if (i2c_cmd_base.s.bus_id == i2c_bus_1) {
> +		writel(i2c_cmd_base.ul, privdata->mmio + AMD_C2P_MSG1);
> +	} else if (i2c_cmd_base.s.bus_id == i2c_bus_0) {
> +		writel(i2c_cmd_base.ul, privdata->mmio + AMD_C2P_MSG0);
> +	} else {
> +		dev_err(ndev_dev(privdata), "%s Invalid bus id\n", __func__);
> +		return -EINVAL;
> +	}
> +
> +	return 0;
> +}
> +EXPORT_SYMBOL_GPL(amd_mp2_read);
> +
> +int amd_mp2_write(struct pci_dev *dev, struct i2c_config i2c_cfg)
> +{
> +	struct amd_mp2_dev *privdata = pci_get_drvdata(dev);
> +	union i2c_cmd_base i2c_cmd_base;
> +	int i = 0;
> +
> +	privdata->requested = true;
> +	dev_dbg(ndev_dev(privdata), "%s addr: %x id: %d\n", __func__,
> +		i2c_cfg.dev_addr, i2c_cfg.bus_id);
> +
> +	i2c_cmd_base.ul = 0;
> +	i2c_cmd_base.s.i2c_cmd = i2c_write;
> +	i2c_cmd_base.s.dev_addr = i2c_cfg.dev_addr;
> +	i2c_cmd_base.s.length = i2c_cfg.length;
> +	i2c_cmd_base.s.bus_id = i2c_cfg.bus_id;
> +
> +	switch (i2c_cfg.i2c_speed) {
> +	case 0:
> +		i2c_cmd_base.s.i2c_speed = speed100k;
> +		break;
> +	case 1:
> +		i2c_cmd_base.s.i2c_speed = speed400k;
> +		break;
> +	case 2:
> +		i2c_cmd_base.s.i2c_speed = speed1000k;
> +		break;
> +	case 3:
> +		i2c_cmd_base.s.i2c_speed = speed1400k;
> +		break;
> +	case 4:
> +		i2c_cmd_base.s.i2c_speed = speed3400k;
> +		break;
> +	default:
> +		dev_err(ndev_dev(privdata), "Invalid ConnectionSpeed\n");
> +	}
> +
> +	if (i2c_cfg.length <= 32) {
> +		i2c_cmd_base.s.mem_type = use_c2pmsg;
> +		for (i = 0; i < ((i2c_cfg.length + 3) / 4); i++) {
> +			writel(i2c_cfg.write_buf[i],
> +			       privdata->mmio + (AMD_C2P_MSG2 + i * 4));
> +		}
> +	} else {
> +		i2c_cmd_base.s.mem_type = use_dram;
> +		privdata->i2c_cfg.phy_addr = i2c_cfg.phy_addr;
> +		write64((u64)privdata->i2c_cfg.phy_addr,
> +			privdata->mmio + AMD_C2P_MSG2);
> +	}
> +
> +	if (i2c_cmd_base.s.bus_id == i2c_bus_1) {
> +		writel(i2c_cmd_base.ul, privdata->mmio + AMD_C2P_MSG1);
> +	} else if (i2c_cmd_base.s.bus_id == i2c_bus_0) {
> +		writel(i2c_cmd_base.ul, privdata->mmio + AMD_C2P_MSG0);
> +	} else {
> +		dev_err(ndev_dev(privdata), "%s Invalid bus id\n", __func__);
> +		return -EINVAL;
> +	}
> +
> +	return 0;
> +}
> +EXPORT_SYMBOL_GPL(amd_mp2_write);
> +
> +int amd_i2c_register_cb(struct pci_dev *dev, const struct  
> amd_i2c_pci_ops *ops,
> +			void *dev_ctx)
> +{
> +	struct amd_mp2_dev *privdata = pci_get_drvdata(dev);
> +
> +	privdata->ops = ops;
> +	privdata->i2c_dev_ctx = dev_ctx;
> +
> +	if (!privdata->ops || !privdata->i2c_dev_ctx)
> +		return -EINVAL;
> +
> +	return 0;
> +}
> +EXPORT_SYMBOL_GPL(amd_i2c_register_cb);
> +
> +static void amd_mp2_pci_work(struct work_struct *work)
> +{
> +	struct amd_mp2_dev *privdata = mp2_dev(work);
> +	u32 readdata = 0;
> +	int i = 0;
> +	int sts = privdata->eventval.base.r.status;
> +	int res = privdata->eventval.base.r.response;
> +	int len = privdata->eventval.base.r.length;
> +
> +	if (res == command_success && sts == i2c_readcomplete_event) {
> +		if (privdata->ops->read_complete) {
> +			if (len <= 32) {
> +				for (i = 0; i < ((len + 3) / 4); i++) {
> +					readdata = readl(privdata->mmio +
> +							(AMD_C2P_MSG2 + i * 4));
> +					privdata->eventval.buf[i] = readdata;
> +				}
> +				privdata->ops->read_complete(privdata->eventval,
> +						privdata->i2c_dev_ctx);
> +			} else {
> +				privdata->ops->read_complete(privdata->eventval,
> +						privdata->i2c_dev_ctx);
> +			}
> +		}
> +	} else if (res == command_success && sts == i2c_writecomplete_event) {
> +		if (privdata->ops->write_complete)
> +			privdata->ops->write_complete(privdata->eventval,
> +					privdata->i2c_dev_ctx);
> +	} else if (res == command_success && sts == i2c_busenable_complete) {
> +		if (privdata->ops->connect_complete)
> +			privdata->ops->connect_complete(privdata->eventval,
> +					privdata->i2c_dev_ctx);
> +	} else {
> +		dev_err(ndev_dev(privdata), "ERROR!!nothing to be handled !\n");
> +	}
> +}
> +
> +static irqreturn_t amd_mp2_irq_isr(int irq, void *dev)
> +{
> +	struct amd_mp2_dev *privdata = dev;
> +	u32 val = 0;
> +	unsigned long  flags;
> +
> +	raw_spin_lock_irqsave(&privdata->lock, flags);
> +	val = readl(privdata->mmio + AMD_P2C_MSG1);
> +	if (val != 0) {
> +		writel(0, privdata->mmio + AMD_P2C_MSG_INTEN);
> +		privdata->eventval.base.ul = val;
> +	} else {
> +		val = readl(privdata->mmio + AMD_P2C_MSG2);
> +		if (val != 0) {
> +			writel(0, privdata->mmio + AMD_P2C_MSG_INTEN);
> +			privdata->eventval.base.ul = val;
> +		}
> +	}
> +
> +	raw_spin_unlock_irqrestore(&privdata->lock, flags);
> +	if (!privdata->ops)
> +		return IRQ_NONE;
> +
> +	if (!privdata->requested)
> +		return IRQ_HANDLED;
> +
> +	privdata->requested = false;
> +	schedule_delayed_work(&privdata->work, 0);
> +
> +	return IRQ_HANDLED;
> +}
> +
> +static ssize_t amd_mp2_debugfs_read(struct file *filp, char __user *ubuf,
> +				    size_t count, loff_t *offp)
> +{
> +	struct amd_mp2_dev *privdata;
> +	void __iomem *mmio;
> +	u8 *buf;
> +	u32 data;
> +	size_t buf_size;
> +	ssize_t ret, off;
> +
> +	privdata = filp->private_data;
> +	mmio = privdata->mmio;
> +	buf_size = min(count, 0x800ul);
> +	buf = kmalloc(buf_size, GFP_KERNEL);
> +
> +	if (!buf)
> +		return -ENOMEM;
> +
> +	off = 0;
> +	off += scnprintf(buf + off, buf_size - off,
> +			"Mp2 Device Information:\n");
> +
> +	off += scnprintf(buf + off, buf_size - off,
> +			"========================\n");
> +	off += scnprintf(buf + off, buf_size - off,
> +			"\tMP2 C2P Message Register Dump:\n\n");
> +	data = readl(privdata->mmio + AMD_C2P_MSG0);
> +	off += scnprintf(buf + off, buf_size - off,
> +			"AMD_C2P_MSG0 -\t\t\t%#06x\n", data);
> +
> +	data = readl(privdata->mmio + AMD_C2P_MSG1);
> +	off += scnprintf(buf + off, buf_size - off,
> +			"AMD_C2P_MSG1 -\t\t\t%#06x\n", data);
> +
> +	data = readl(privdata->mmio + AMD_C2P_MSG2);
> +	off += scnprintf(buf + off, buf_size - off,
> +			"AMD_C2P_MSG2 -\t\t\t%#06x\n", data);
> +
> +	data = readl(privdata->mmio + AMD_C2P_MSG3);
> +	off += scnprintf(buf + off, buf_size - off,
> +			"AMD_C2P_MSG3 -\t\t\t%#06x\n", data);
> +
> +	data = readl(privdata->mmio + AMD_C2P_MSG4);
> +	off += scnprintf(buf + off, buf_size - off,
> +			"AMD_C2P_MSG4 -\t\t\t%#06x\n", data);
> +
> +	data = readl(privdata->mmio + AMD_C2P_MSG5);
> +	off += scnprintf(buf + off, buf_size - off,
> +			"AMD_C2P_MSG5 -\t\t\t%#06x\n", data);
> +
> +	data = readl(privdata->mmio + AMD_C2P_MSG6);
> +	off += scnprintf(buf + off, buf_size - off,
> +			"AMD_C2P_MSG6 -\t\t\t%#06x\n", data);
> +
> +	data = readl(privdata->mmio + AMD_C2P_MSG7);
> +	off += scnprintf(buf + off, buf_size - off,
> +			"AMD_C2P_MSG7 -\t\t\t%#06x\n", data);
> +
> +	data = readl(privdata->mmio + AMD_C2P_MSG8);
> +	off += scnprintf(buf + off, buf_size - off,
> +			"AMD_C2P_MSG8 -\t\t\t%#06x\n", data);
> +
> +	data = readl(privdata->mmio + AMD_C2P_MSG9);
> +	off += scnprintf(buf + off, buf_size - off,
> +			"AMD_C2P_MSG9 -\t\t\t%#06x\n", data);
> +
> +	off += scnprintf(buf + off, buf_size - off,
> +			"\n\tMP2 P2C Message Register Dump:\n\n");
> +
> +	data = readl(privdata->mmio + AMD_P2C_MSG1);
> +	off += scnprintf(buf + off, buf_size - off,
> +			"AMD_P2C_MSG1 -\t\t\t%#06x\n", data);
> +
> +	data = readl(privdata->mmio + AMD_P2C_MSG2);
> +	off += scnprintf(buf + off, buf_size - off,
> +			"AMD_P2C_MSG2 -\t\t\t%#06x\n", data);
> +
> +	data = readl(privdata->mmio + AMD_P2C_MSG_INTEN);
> +	off += scnprintf(buf + off, buf_size - off,
> +			"AMD_P2C_MSG_INTEN -\t\t%#06x\n", data);
> +
> +	data = readl(privdata->mmio + AMD_P2C_MSG_INTSTS);
> +	off += scnprintf(buf + off, buf_size - off,
> +			"AMD_P2C_MSG_INTSTS -\t\t%#06x\n", data);
> +
> +	ret = simple_read_from_buffer(ubuf, count, offp, buf, off);
> +	kfree(buf);
> +	return ret;
> +}
> +
> +static void amd_mp2_init_debugfs(struct amd_mp2_dev *privdata)
> +{
> +	if (!debugfs_dir) {
> +		privdata->debugfs_dir = NULL;
> +		privdata->debugfs_info = NULL;
> +	} else {
> +		privdata->debugfs_dir = debugfs_create_dir(ndev_name(privdata),
> +							   debugfs_dir);
> +		if (!privdata->debugfs_dir) {
> +			privdata->debugfs_info = NULL;
> +		} else {
> +			privdata->debugfs_info = debugfs_create_file
> +				("info", 0400, privdata->debugfs_dir,
> +					privdata, &amd_mp2_debugfs_info);
> +		}
> +	}
> +}
> +
> +static void amd_mp2_deinit_debugfs(struct amd_mp2_dev *privdata)
> +{
> +	debugfs_remove_recursive(privdata->debugfs_dir);
> +}
> +
> +static void amd_mp2_clear_reg(struct amd_mp2_dev *privdata)
> +{
> +	int reg = 0;
> +
> +	for (reg = AMD_C2P_MSG0; reg <= AMD_C2P_MSG9; reg += 4)
> +		writel(0, privdata->mmio + reg);
> +
> +	for (reg = AMD_P2C_MSG0; reg <= AMD_P2C_MSG2; reg += 4)
> +		writel(0, privdata->mmio + reg);
> +}
> +
> +static int amd_mp2_pci_init(struct amd_mp2_dev *privdata, struct pci_dev  
> *pdev)
> +{
> +	int rc;
> +	int bar_index = 2;
> +	resource_size_t size, base;
> +
> +	pci_set_drvdata(pdev, privdata);
> +
> +	rc = pci_enable_device(pdev);
> +	if (rc)
> +		goto err_pci_enable;
> +
> +	rc = pci_request_regions(pdev, DRIVER_NAME);
> +	if (rc)
> +		goto err_pci_regions;
> +
> +	pci_set_master(pdev);
> +
> +	rc = pci_set_dma_mask(pdev, DMA_BIT_MASK(64));
> +	if (rc) {
> +		rc = pci_set_dma_mask(pdev, DMA_BIT_MASK(32));
> +		if (rc)
> +			goto err_dma_mask;
> +		dev_warn(ndev_dev(privdata), "Cannot DMA highmem\n");
> +	}
> +
> +	rc = pci_set_consistent_dma_mask(pdev, DMA_BIT_MASK(64));
> +	if (rc) {
> +		rc = pci_set_consistent_dma_mask(pdev, DMA_BIT_MASK(32));
> +		if (rc)
> +			goto err_dma_mask;
> +		dev_warn(ndev_dev(privdata), "Cannot DMA consistent highmem\n");
> +	}
> +
> +	base = pci_resource_start(pdev, bar_index);
> +	size = pci_resource_len(pdev, bar_index);
> +
> +	privdata->mmio = ioremap(base, size);
> +	if (!privdata->mmio) {
> +		rc = -EIO;
> +		goto err_dma_mask;
> +	}
> +
> +	/* Try to set up intx irq */
> +	pci_intx(pdev, 1);
> +	privdata->eventval.buf = NULL;
> +	privdata->requested = false;
> +	raw_spin_lock_init(&privdata->lock);
> +	rc = request_irq(pdev->irq, amd_mp2_irq_isr, IRQF_SHARED, "mp2_irq_isr",
> +			 privdata);
> +	if (rc)
> +		goto err_intx_request;
> +
> +	return 0;
> +
> +err_intx_request:
> +	return rc;
> +err_dma_mask:
> +	pci_clear_master(pdev);
> +	pci_release_regions(pdev);
> +err_pci_regions:
> +	pci_disable_device(pdev);
> +err_pci_enable:
> +	pci_set_drvdata(pdev, NULL);
> +	return rc;
> +}
> +
> +static void amd_mp2_pci_deinit(struct amd_mp2_dev *privdata)
> +{
> +	struct pci_dev *pdev = ndev_pdev(privdata);
> +
> +	pci_iounmap(pdev, privdata->mmio);
> +
> +	pci_clear_master(pdev);
> +	pci_release_regions(pdev);
> +	pci_disable_device(pdev);
> +	pci_set_drvdata(pdev, NULL);
> +}
> +
> +static int amd_mp2_pci_probe(struct pci_dev *pdev,
> +			     const struct pci_device_id *id)
> +{
> +	struct amd_mp2_dev *privdata;
> +	int rc;
> +
> +	dev_info(&pdev->dev, "MP2 device found [%04x:%04x] (rev %x)\n",
> +		 (int)pdev->vendor, (int)pdev->device, (int)pdev->revision);
> +
> +	privdata = kzalloc(sizeof(*privdata), GFP_KERNEL);
> +	privdata->pdev = pdev;
> +
> +	if (!privdata) {
> +		rc = -ENOMEM;
> +		goto err_dev;
> +	}
> +
> +	rc = amd_mp2_pci_init(privdata, pdev);
> +	if (rc)
> +		goto err_pci_init;
> +	dev_dbg(&pdev->dev, "pci init done.\n");
> +
> +	INIT_DELAYED_WORK(&privdata->work, amd_mp2_pci_work);
> +
> +	amd_mp2_init_debugfs(privdata);
> +	dev_info(&pdev->dev, "MP2 device registered.\n");
> +	return 0;
> +
> +err_pci_init:
> +	kfree(privdata);
> +err_dev:
> +	dev_err(&pdev->dev, "Memory Allocation Failed\n");
> +	return rc;
> +}
> +
> +static void amd_mp2_pci_remove(struct pci_dev *pdev)
> +{
> +	struct amd_mp2_dev *privdata = pci_get_drvdata(pdev);
> +
> +	amd_mp2_deinit_debugfs(privdata);
> +	amd_mp2_clear_reg(privdata);
> +	cancel_delayed_work_sync(&privdata->work);
> +	free_irq(pdev->irq, privdata);
> +	pci_intx(pdev, 0);
> +	amd_mp2_pci_deinit(privdata);
> +	kfree(privdata);
> +}
> +
> +static const struct file_operations amd_mp2_debugfs_info = {
> +	.owner = THIS_MODULE,
> +	.open = simple_open,
> +	.read = amd_mp2_debugfs_read,
> +};
> +
> +static const struct pci_device_id amd_mp2_pci_tbl[] = {
> +	{PCI_VDEVICE(AMD, PCI_DEVICE_ID_AMD_MP2)},
> +	{0}
> +};
> +MODULE_DEVICE_TABLE(pci, amd_mp2_pci_tbl);
> +
> +#ifdef CONFIG_PM_SLEEP
> +static int amd_mp2_pci_device_suspend(struct pci_dev *pdev, pm_message_t  
> mesg)
> +{
> +	struct amd_mp2_dev *privdata = pci_get_drvdata(pdev);
> +
> +	if (!privdata)
> +		return -EINVAL;
> +
> +	return 0;
> +}
> +
> +static int amd_mp2_pci_device_resume(struct pci_dev *pdev)
> +{
> +	struct amd_mp2_dev *privdata = pci_get_drvdata(pdev);
> +
> +	if (!privdata)
> +		return -EINVAL;
> +
> +	return 0;
> +}
> +#endif
> +
> +static struct pci_driver amd_mp2_pci_driver = {
> +	.name		= DRIVER_NAME,
> +	.id_table	= amd_mp2_pci_tbl,
> +	.probe		= amd_mp2_pci_probe,
> +	.remove		= amd_mp2_pci_remove,
> +#ifdef CONFIG_PM_SLEEP
> +	.suspend		= amd_mp2_pci_device_suspend,
> +	.resume			= amd_mp2_pci_device_resume,
> +#endif
> +};
> +
> +static int __init amd_mp2_pci_driver_init(void)
> +{
> +	pr_info("%s: %s Version: %s\n", DRIVER_NAME, DRIVER_DESC, DRIVER_VER);
> +
> +	if (debugfs_initialized())
> +		debugfs_dir = debugfs_create_dir(KBUILD_MODNAME, NULL);
> +
> +	return pci_register_driver(&amd_mp2_pci_driver);
> +}
> +module_init(amd_mp2_pci_driver_init);
> +
> +static void __exit amd_mp2_pci_driver_exit(void)
> +{
> +	pci_unregister_driver(&amd_mp2_pci_driver);
> +	debugfs_remove_recursive(debugfs_dir);
> +}
> +module_exit(amd_mp2_pci_driver_exit);
> diff --git a/drivers/i2c/busses/i2c-amd-pci-mp2.h  
> b/drivers/i2c/busses/i2c-amd-pci-mp2.h
> new file mode 100644
> index 0000000..787484e
> --- /dev/null
> +++ b/drivers/i2c/busses/i2c-amd-pci-mp2.h
> @@ -0,0 +1,196 @@
> +/* SPDX-License-Identifier: GPL-2.0
> + *
> + * Copyright (C) 2018 Advanced Micro Devices, Inc. All Rights Reserved
> + *
> + * Author: Shyam Sundar S K <Shyam-sundar.S-k@amd.com>
> + * AMD PCIe MP2 Communication Interface Driver
> + */
> +
> +#ifndef I2C_AMD_PCI_MP2_H
> +#define I2C_AMD_PCI_MP2_H
> +
> +#include <linux/pci.h>
> +
> +#define PCI_DEVICE_ID_AMD_MP2	0x15E6
> +
> +#define write64 _write64
> +static inline void _write64(u64 val, void __iomem *mmio)
> +{
> +	writel(val, mmio);
> +	writel(val >> 32, mmio + sizeof(u32));
> +}
> +
> +#define read64 _read64
> +static inline u64 _read64(void __iomem *mmio)
> +{
> +	u64 low, high;
> +
> +	low = readl(mmio);
> +	high = readl(mmio + sizeof(u32));
> +	return low | (high << 32);
> +}
> +
> +enum {
> +	/* MP2 C2P Message Registers */
> +	AMD_C2P_MSG0 = 0x10500, /*MP2 Message for I2C0*/
> +	AMD_C2P_MSG1 = 0x10504, /*MP2 Message for I2C1*/
> +	AMD_C2P_MSG2 = 0x10508, /*DRAM Address Lo / Data 0*/
> +	AMD_C2P_MSG3 = 0x1050c, /*DRAM Address HI / Data 1*/
> +	AMD_C2P_MSG4 = 0x10510, /*Data 2*/
> +	AMD_C2P_MSG5 = 0x10514, /*Data 3*/
> +	AMD_C2P_MSG6 = 0x10518, /*Data 4*/
> +	AMD_C2P_MSG7 = 0x1051c, /*Data 5*/
> +	AMD_C2P_MSG8 = 0x10520, /*Data 6*/
> +	AMD_C2P_MSG9 = 0x10524, /*Data 7*/
> +
> +	/* MP2 P2C Message Registers */
> +	AMD_P2C_MSG0 = 0x10680, /*Do not use*/
> +	AMD_P2C_MSG1 = 0x10684, /*I2c0 int reg*/
> +	AMD_P2C_MSG2 = 0x10688, /*I2c1 int reg*/
> +	AMD_P2C_MSG3 = 0x1068C, /*MP2 debug info*/
> +	AMD_P2C_MSG_INTEN = 0x10690, /*MP2 int gen register*/
> +	AMD_P2C_MSG_INTSTS = 0x10694, /*Interrupt sts*/
> +};
> +
> +/* Command register data structures */
> +
> +enum i2c_cmd {
> +	i2c_read,
> +	i2c_write,
> +	i2c_enable,
> +	i2c_disable,
> +	number_of_sensor_discovered,
> +	is_mp2_active,
> +	invalid_cmd = 0xF,
> +};
> +
> +enum i2c_bus_index {
> +	i2c_bus_0 = 0,
> +	i2c_bus_1 = 1,
> +	i2c_bus_max
> +};
> +
> +enum speed_enum {
> +	speed100k = 0,
> +	speed400k = 1,
> +	speed1000k = 2,
> +	speed1400k = 3,
> +	speed3400k = 4
> +};
> +
> +enum mem_type {
> +	use_dram = 0,
> +	use_c2pmsg = 1,
> +};
> +
> +union i2c_cmd_base {
> +	u32 ul;
> +	struct {
> +		enum i2c_cmd i2c_cmd : 4; /*!< bit: 0..3 i2c R/W command */
> +		enum i2c_bus_index bus_id : 4; /*!< bit: 4..7 i2c bus index */
> +		u32 dev_addr : 8; /*!< bit: 8..15 device address or Bus Speed*/
> +		u32 length : 12; /*!< bit: 16..29 read/write length */
> +		enum speed_enum i2c_speed : 3; /*!< bit: 30 register address*/
> +		enum mem_type mem_type : 1; /*!< bit: 15 mem type*/
> +	} s; /*!< Structure used for bit access */
> +};
> +
> +/* Response register data structures */
> +
> +/*Response - Response of SFI*/
> +enum response_type {
> +	invalid_response = 0,
> +	command_success = 1,
> +	command_failed = 2,
> +};
> +
> +/*Status - Command ID to indicate a command*/
> +enum status_type {
> +	i2c_readcomplete_event = 0,
> +	i2c_readfail_event = 1,
> +	i2c_writecomplete_event = 2,
> +	i2c_writefail_event = 3,
> +	i2c_busenable_complete = 4,
> +	i2c_busenable_failed = 5,
> +	i2c_busdisable_complete = 6,
> +	i2c_busdisable_failed = 7,
> +	invalid_data_length = 8,
> +	invalid_slave_address = 9,
> +	invalid_i2cbus_id = 10,
> +	invalid_dram_addr = 11,
> +	invalid_command = 12,
> +	mp2_active = 13,
> +	numberof_sensors_discovered_resp = 14,
> +	i2C_bus_notinitialized
> +};
> +
> +struct i2c_event {
> +	union {
> +		u32 ul;
> +		struct {
> +			enum response_type response : 2; /*!< bit: 0..1 I2C res type */
> +			enum status_type status : 5; /*!< bit: 2..6 status_type */
> +			enum mem_type mem_type : 1; /*!< bit: 7 0-DRAM;1- C2PMsg o/p */
> +			enum i2c_bus_index bus_id : 4; /*!< bit: 8..11 I2C Bus ID */
> +			u32 length : 12; /*!< bit:16..29 length */
> +			u32 slave_addr : 8; /*!< bit: 15 debug msg include in p2c msg */
> +		} r; /*!< Structure used for bit access */
> +	} base;
> +	u32 *buf;
> +};
> +
> +/* data structures for communication with I2c*/
> +
> +struct i2c_config {
> +	enum i2c_bus_index bus_id;
> +	u64 i2c_speed;
> +	u16 dev_addr;
> +	u32 length;
> +	phys_addr_t phy_addr;
> +	u8 *read_buf;
> +	u32 *write_buf;
> +};
> +
> +/* struct to send/receive data b/w pci and i2c drivers*/
> +struct amd_i2c_pci_ops {
> +	int (*read_complete)(struct i2c_event event, void *dev_ctx);
> +	int (*write_complete)(struct i2c_event event, void *dev_ctx);
> +	int (*connect_complete)(struct i2c_event event, void *dev_ctx);
> +};
> +
> +struct amd_i2c_common {
> +	struct i2c_config i2c_cfg;
> +	const struct amd_i2c_pci_ops *ops;
> +	struct pci_dev *pdev;
> +};
> +
> +struct amd_mp2_dev {
> +	struct pci_dev *pdev;
> +	struct dentry *debugfs_dir;
> +	struct dentry *debugfs_info;
> +	void __iomem *mmio;
> +	struct i2c_event eventval;
> +	enum i2c_cmd reqcmd;
> +	struct i2c_config i2c_cfg;
> +	union i2c_cmd_base i2c_cmd_base;
> +	const struct amd_i2c_pci_ops *ops;
> +	struct delayed_work work;
> +	void *i2c_dev_ctx;
> +	bool requested;
> +	raw_spinlock_t lock;
> +};
> +
> +int amd_mp2_read(struct pci_dev *pdev, struct i2c_config i2c_cfg);
> +int amd_mp2_write(struct pci_dev *pdev,
> +		  struct i2c_config i2c_cfg);
> +int amd_mp2_connect(struct pci_dev *pdev,
> +		    struct i2c_config i2c_cfg);
> +int amd_i2c_register_cb(struct pci_dev *pdev, const struct  
> amd_i2c_pci_ops *ops,
> +			void *dev_ctx);
> +
> +#define ndev_pdev(ndev) ((ndev)->pdev)
> +#define ndev_name(ndev) pci_name(ndev_pdev(ndev))
> +#define ndev_dev(ndev) (&ndev_pdev(ndev)->dev)
> +#define mp2_dev(__work) container_of(__work, struct amd_mp2_dev,  
> work.work)
> +
> +#endif
> diff --git a/drivers/i2c/busses/i2c-amd-platdrv.c  
> b/drivers/i2c/busses/i2c-amd-platdrv.c
> new file mode 100644
> index 0000000..95e3b37
> --- /dev/null
> +++ b/drivers/i2c/busses/i2c-amd-platdrv.c
> @@ -0,0 +1,277 @@
> +// SPDX-License-Identifier: GPL-2.0
> +/*
> + *
> + * Copyright (C) 2018 Advanced Micro Devices, Inc. All Rights Reserved.
> + *
> + *
> + * Author: Nehal Bakulchandra Shah <Nehal-bakulchandra.shah@amd.com>
> + * AMD I2C Platform Driver
> + */
> +
> +#include <linux/kernel.h>
> +#include <linux/module.h>
> +#include <linux/types.h>
> +#include <linux/slab.h>
> +#include <linux/i2c.h>
> +#include <linux/platform_device.h>
> +#include <linux/dma-mapping.h>
> +#include <linux/acpi.h>
> +#include <linux/delay.h>
> +#include "i2c-amd-pci-mp2.h"
> +
> +struct amd_i2c_dev {
> +	struct platform_device *pdev;
> +	struct i2c_adapter adapter;
> +	struct amd_i2c_common i2c_common;
> +	struct completion msg_complete;
> +	struct i2c_msg *msg_buf;
> +	bool is_configured;
> +	u8 bus_id;
> +	u8 *buf;
> +};
> +
> +static int i2c_amd_read_completion(struct i2c_event event, void *dev_ctx)
> +{
> +	struct amd_i2c_dev *i2c_dev = (struct amd_i2c_dev *)dev_ctx;
> +	struct amd_i2c_common *commond = &i2c_dev->i2c_common;
> +	int i = 0;
> +
> +	if (event.base.r.status == i2c_readcomplete_event) {
> +		if (event.base.r.length <= 32) {
> +			pr_devel(" in %s i2c_dev->msg_buf :%p\n",
> +				 __func__, i2c_dev->msg_buf);
> +
> +			memcpy(i2c_dev->msg_buf->buf,
> +			       (unsigned char *)event.buf, event.base.r.length);
> +
> +			for (i = 0; i < ((event.base.r.length + 3) / 4); i++)
> +				pr_devel("%s: readdata:%x\n",
> +					 __func__, event.buf[i]);
> +
> +		} else {
> +			memcpy(i2c_dev->msg_buf->buf,
> +			       (unsigned char *)commond->i2c_cfg.read_buf,
> +				event.base.r.length);
> +
> +			for (i = 0; i < ((event.base.r.length + 3) / 4); i++)
> +				pr_devel("%s: readdata:%x\n", __func__,
> +					 ((unsigned int *)commond->i2c_cfg.read_buf)[i]);
> +		}
> +
> +				complete(&i2c_dev->msg_complete);
> +	}
> +
> +	return 0;
> +}
> +
> +static int i2c_amd_write_completion(struct i2c_event event, void *dev_ctx)
> +{
> +	struct amd_i2c_dev *i2c_dev = (struct amd_i2c_dev *)dev_ctx;
> +
> +	if (event.base.r.status == i2c_writecomplete_event)
> +			complete(&i2c_dev->msg_complete);
> +
> +	return 0;
> +}
> +
> +static int i2c_amd_connect_completion(struct i2c_event event, void  
> *dev_ctx)
> +{
> +	struct amd_i2c_dev *i2c_dev = (struct amd_i2c_dev *)dev_ctx;
> +
> +	if (event.base.r.status == i2c_busenable_complete)
> +			complete(&i2c_dev->msg_complete);
> +
> +	return 0;
> +}
> +
> +static const struct amd_i2c_pci_ops data_handler = {
> +		.read_complete = i2c_amd_read_completion,
> +		.write_complete = i2c_amd_write_completion,
> +		.connect_complete = i2c_amd_connect_completion,
> +};
> +
> +static int i2c_amd_pci_configure(struct amd_i2c_dev *i2c_dev, int  
> slaveaddr)
> +{
> +	struct amd_i2c_common *i2c_common = &i2c_dev->i2c_common;
> +	int ret;
> +
> +	amd_i2c_register_cb(i2c_common->pdev, &data_handler, (void *)i2c_dev);
> +	i2c_common->i2c_cfg.bus_id = i2c_dev->bus_id;
> +	i2c_common->i2c_cfg.dev_addr = slaveaddr;
> +	i2c_common->i2c_cfg.i2c_speed = speed400k;
> +	ret = amd_mp2_connect(i2c_common->pdev, i2c_common->i2c_cfg);
> +
> +	if (ret)
> +		return	-EIO;
> +
> +	mdelay(100);
> +
> +	return 0;
> +}
> +
> +static int i2c_amd_xfer(struct i2c_adapter *adap, struct i2c_msg *msgs,  
> int num)
> +{
> +	struct amd_i2c_dev *dev = i2c_get_adapdata(adap);
> +	struct amd_i2c_common *i2c_common = &dev->i2c_common;
> +
> +	int i;
> +	unsigned long timeout;
> +	struct i2c_msg *pmsg;
> +	unsigned char *dma_buf = NULL;
> +	dma_addr_t phys;
> +
> +	reinit_completion(&dev->msg_complete);
> +	if (dev->is_configured == 0) {
> +		i2c_amd_pci_configure(dev, msgs->addr);
> +		timeout = wait_for_completion_timeout(&dev->msg_complete, 50);
> +		dev->is_configured = 1;
> +	}
> +
> +	for (i = 0; i < num; i++) {
> +		pmsg = &msgs[i];
> +		i2c_common->i2c_cfg.length = pmsg->len;
> +		if (pmsg->len > 32) {
> +			dma_buf = (u8 *)dma_alloc_coherent(&i2c_common->pdev->dev,
> +					pmsg->len, &phys, GFP_KERNEL);
> +			i2c_common->i2c_cfg.phy_addr = phys;
> +		}
> +
> +		if (pmsg->flags & I2C_M_RD) {
> +			if (pmsg->len <= 32)
> +				i2c_common->i2c_cfg.read_buf = dev->buf;
> +			else
> +				i2c_common->i2c_cfg.read_buf = dma_buf;
> +
> +			dev->msg_buf = pmsg;
> +			amd_mp2_read(i2c_common->pdev,
> +				     i2c_common->i2c_cfg);
> +
> +		} else {
> +			if (pmsg->len <= 32)
> +				i2c_common->i2c_cfg.write_buf = (unsigned int *)pmsg->buf;
> +			else
> +				i2c_common->i2c_cfg.write_buf = (unsigned int *)dma_buf;
> +
> +			amd_mp2_write(i2c_common->pdev,
> +				      i2c_common->i2c_cfg);
> +		}
> +
> +		timeout = wait_for_completion_timeout
> +					(&dev->msg_complete, 50);
> +		if (dma_buf)
> +			dma_free_coherent(&i2c_common->pdev->dev,
> +					  pmsg->len, dma_buf, phys);
> +
> +		if (timeout == 0)
> +			return -ETIMEDOUT;
> +	}
> +	return num;
> +}
> +
> +static u32 i2c_amd_func(struct i2c_adapter *a)
> +{
> +	return I2C_FUNC_I2C;
> +}
> +
> +static const struct i2c_algorithm i2c_amd_algorithm = {
> +	.master_xfer = i2c_amd_xfer,
> +	.functionality = i2c_amd_func,
> +};
> +
> +static int i2c_amd_probe(struct platform_device *pdev)
> +{
> +	int ret;
> +	struct amd_i2c_dev *i2c_dev;
> +	struct device *dev = &pdev->dev;
> +	acpi_handle handle = ACPI_HANDLE(&pdev->dev);
> +	struct acpi_device *adev;
> +	const char *uid = NULL;
> +
> +	i2c_dev = devm_kzalloc(dev, sizeof(*i2c_dev), GFP_KERNEL);
> +	if (!i2c_dev)
> +		return -ENOMEM;
> +
> +	i2c_dev->pdev = pdev;
> +
> +	if (!acpi_bus_get_device(handle, &adev)) {
> +		pr_err(" i2c0  pdev->id=%s\n", adev->pnp.unique_id);
> +		uid = adev->pnp.unique_id;
> +	}
> +
> +	if (strcmp(uid, "0") == 0) {
> +		pr_err(" bus id is 0\n");
> +		i2c_dev->bus_id = 0;
> +	}
> +
> +	pr_devel(" i2c1  pdev->id=%s\n", uid);
> +	if (strcmp(uid, "1") == 0) {
> +		pr_err(" bus id is 1\n");
> +		i2c_dev->bus_id = 1;
> +	}
> +	/* setup i2c adapter description */
> +	i2c_dev->adapter.owner = THIS_MODULE;
> +	i2c_dev->adapter.algo = &i2c_amd_algorithm;
> +	i2c_dev->adapter.dev.parent = dev;
> +	i2c_dev->adapter.algo_data = i2c_dev;
> +	ACPI_COMPANION_SET(&i2c_dev->adapter.dev, ACPI_COMPANION(&pdev->dev));
> +	i2c_dev->adapter.dev.of_node = dev->of_node;
> +	/*buffer for 32 bytes of read  data*/
> +	i2c_dev->buf = kzalloc(32, GFP_KERNEL);
> +
> +	if (!i2c_dev->buf)
> +		return -ENOMEM;
> +
> +	snprintf(i2c_dev->adapter.name, sizeof(i2c_dev->adapter.name), "%s-%s",
> +		 "i2c_dev-i2c", dev_name(pdev->dev.parent));
> +
> +	i2c_dev->i2c_common.pdev = pci_get_device(PCI_VENDOR_ID_AMD,
> +						  PCI_DEVICE_ID_AMD_MP2, NULL);
> +
> +	if (!i2c_dev->i2c_common.pdev) {
> +		pr_err("%s Could not find pdev in i2c\n", __func__);
> +		return -EINVAL;
> +	}
> +	platform_set_drvdata(pdev, i2c_dev);
> +	i2c_set_adapdata(&i2c_dev->adapter, i2c_dev);
> +
> +	init_completion(&i2c_dev->msg_complete);
> +	/* and finally attach to i2c layer */
> +	ret = i2c_add_adapter(&i2c_dev->adapter);
> +
> +	if (ret < 0)
> +		pr_err(" i2c add adpater failed =%d", ret);
> +
> +	return ret;
> +}
> +
> +static int i2c_amd_remove(struct platform_device *pdev)
> +{
> +	struct amd_i2c_dev *i2c_dev = platform_get_drvdata(pdev);
> +
> +	kfree(i2c_dev->buf);
> +
> +	i2c_del_adapter(&i2c_dev->adapter);
> +
> +	return 0;
> +}
> +
> +static const struct acpi_device_id i2c_amd_acpi_match[] = {
> +		{ "AMDI0011" },
> +		{ },
> +};
> +
> +static struct platform_driver amd_i2c_plat_driver = {
> +		.probe = i2c_amd_probe,
> +		.remove = i2c_amd_remove,
> +		.driver = {
> +				.name = "i2c_amd_platdrv",
> +				.acpi_match_table = ACPI_PTR
> +						(i2c_amd_acpi_match),
> +		},
> +};
> +
> +module_platform_driver(amd_i2c_plat_driver);
> +
> +MODULE_AUTHOR("Nehal Shah <nehal-bakulchandra.shah@amd.com>");
> +MODULE_DESCRIPTION("AMD I2C Platform Driver");
> +MODULE_LICENSE("Dual BSD/GPL");
> -- 
> 2.7.4

Patch

diff --git a/drivers/i2c/busses/Kconfig b/drivers/i2c/busses/Kconfig
index 8d21b98..ff68424 100644
--- a/drivers/i2c/busses/Kconfig
+++ b/drivers/i2c/busses/Kconfig
@@ -77,6 +77,16 @@  config I2C_AMD8111
 	  This driver can also be built as a module.  If so, the module
 	  will be called i2c-amd8111.
 
+config I2C_AMD_MP2
+	tristate "AMD MP2"
+	depends on ACPI && PCI
+	help
+	  If you say yes to this option, support will be included for mp2
+	  I2C interface.
+
+	  This driver can also be built as a module.  If so, the module
+	  will be called i2c-amd-platdrv.
+
 config I2C_HIX5HD2
 	tristate "Hix5hd2 high-speed I2C driver"
 	depends on ARCH_HISI || ARCH_HIX5HD2 || COMPILE_TEST
diff --git a/drivers/i2c/busses/Makefile b/drivers/i2c/busses/Makefile
index 189e34b..b01e46b 100644
--- a/drivers/i2c/busses/Makefile
+++ b/drivers/i2c/busses/Makefile
@@ -113,6 +113,8 @@  obj-$(CONFIG_I2C_XLR)		+= i2c-xlr.o
 obj-$(CONFIG_I2C_XLP9XX)	+= i2c-xlp9xx.o
 obj-$(CONFIG_I2C_RCAR)		+= i2c-rcar.o
 obj-$(CONFIG_I2C_ZX2967)	+= i2c-zx2967.o
+obj-$(CONFIG_I2C_AMD_MP2)   	+= i2c-amd-pci-mp2.o
+obj-$(CONFIG_I2C_AMD_MP2)   	+= i2c-amd-platdrv.o
 
 # External I2C/SMBus adapter drivers
 obj-$(CONFIG_I2C_DIOLAN_U2C)	+= i2c-diolan-u2c.o
diff --git a/drivers/i2c/busses/i2c-amd-pci-mp2.c b/drivers/i2c/busses/i2c-amd-pci-mp2.c
new file mode 100644
index 0000000..984314c
--- /dev/null
+++ b/drivers/i2c/busses/i2c-amd-pci-mp2.c
@@ -0,0 +1,580 @@ 
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * Copyright (C) 2018 Advanced Micro Devices, Inc. All Rights Reserved.
+ *
+ *
+ * Author: Shyam Sundar S K <Shyam-sundar.S-k@amd.com>
+ * AMD PCIe MP2 Communication Driver
+ */
+
+#include <linux/debugfs.h>
+#include <linux/interrupt.h>
+#include <linux/module.h>
+#include <linux/pci.h>
+#include <linux/slab.h>
+
+#include "i2c-amd-pci-mp2.h"
+
+#define DRIVER_NAME	"pcie_mp2_amd"
+#define DRIVER_DESC	"AMD(R) PCI-E MP2 Communication Driver"
+#define DRIVER_VER	"1.0"
+
+MODULE_DESCRIPTION(DRIVER_DESC);
+MODULE_VERSION(DRIVER_VER);
+MODULE_LICENSE("Dual BSD/GPL");
+MODULE_AUTHOR("Shyam Sundar S K <Shyam-sundar.S-k@amd.com>");
+
+static const struct file_operations amd_mp2_debugfs_info;
+static struct dentry *debugfs_dir;
+
+int amd_mp2_connect(struct pci_dev *dev, struct i2c_config i2c_cfg)
+{
+	struct amd_mp2_dev *privdata = pci_get_drvdata(dev);
+	union i2c_cmd_base i2c_cmd_base;
+	unsigned  long  flags;
+
+	raw_spin_lock_irqsave(&privdata->lock, flags);
+	dev_dbg(ndev_dev(privdata), "%s addr: %x id: %d\n", __func__,
+		i2c_cfg.dev_addr, i2c_cfg.bus_id);
+
+	i2c_cmd_base.ul = 0;
+	i2c_cmd_base.s.i2c_cmd = i2c_enable;
+	i2c_cmd_base.s.bus_id = i2c_cfg.bus_id;
+	i2c_cmd_base.s.i2c_speed = i2c_cfg.i2c_speed;
+
+	if (i2c_cmd_base.s.bus_id == i2c_bus_1) {
+		writel(i2c_cmd_base.ul, privdata->mmio + AMD_C2P_MSG1);
+	} else if (i2c_cmd_base.s.bus_id == i2c_bus_0) {
+		writel(i2c_cmd_base.ul, privdata->mmio + AMD_C2P_MSG0);
+	} else {
+		dev_err(ndev_dev(privdata), "%s Invalid bus id\n", __func__);
+		return -EINVAL;
+	}
+	raw_spin_unlock_irqrestore(&privdata->lock, flags);
+	return 0;
+}
+EXPORT_SYMBOL_GPL(amd_mp2_connect);
+
+int amd_mp2_read(struct pci_dev *dev, struct i2c_config i2c_cfg)
+{
+	struct amd_mp2_dev *privdata = pci_get_drvdata(dev);
+	union i2c_cmd_base i2c_cmd_base;
+
+	dev_dbg(ndev_dev(privdata), "%s addr: %x id: %d\n", __func__,
+		i2c_cfg.dev_addr, i2c_cfg.bus_id);
+
+	privdata->requested = true;
+	i2c_cmd_base.ul = 0;
+	i2c_cmd_base.s.i2c_cmd = i2c_read;
+	i2c_cmd_base.s.dev_addr = i2c_cfg.dev_addr;
+	i2c_cmd_base.s.length = i2c_cfg.length;
+	i2c_cmd_base.s.bus_id = i2c_cfg.bus_id;
+
+	if (i2c_cfg.length <= 32) {
+		i2c_cmd_base.s.mem_type = use_c2pmsg;
+		privdata->eventval.buf = (u32 *)i2c_cfg.read_buf;
+		if (!privdata->eventval.buf) {
+			dev_err(ndev_dev(privdata), "%s no mem for buf received\n",
+				__func__);
+			return -ENOMEM;
+		}
+	} else {
+		i2c_cmd_base.s.mem_type = use_dram;
+		privdata->i2c_cfg.phy_addr = i2c_cfg.phy_addr;
+		privdata->i2c_cfg.read_buf = i2c_cfg.read_buf;
+		write64((u64)privdata->i2c_cfg.phy_addr,
+			privdata->mmio + AMD_C2P_MSG2);
+	}
+
+	switch (i2c_cfg.i2c_speed) {
+	case 0:
+		i2c_cmd_base.s.i2c_speed = speed100k;
+		break;
+	case 1:
+		i2c_cmd_base.s.i2c_speed = speed400k;
+		break;
+	case 2:
+		i2c_cmd_base.s.i2c_speed = speed1000k;
+		break;
+	case 3:
+		i2c_cmd_base.s.i2c_speed = speed1400k;
+		break;
+	case 4:
+		i2c_cmd_base.s.i2c_speed = speed3400k;
+		break;
+	default:
+		dev_err(ndev_dev(privdata), "Invalid ConnectionSpeed\n");
+	}
+
+	if (i2c_cmd_base.s.bus_id == i2c_bus_1) {
+		writel(i2c_cmd_base.ul, privdata->mmio + AMD_C2P_MSG1);
+	} else if (i2c_cmd_base.s.bus_id == i2c_bus_0) {
+		writel(i2c_cmd_base.ul, privdata->mmio + AMD_C2P_MSG0);
+	} else {
+		dev_err(ndev_dev(privdata), "%s Invalid bus id\n", __func__);
+		return -EINVAL;
+	}
+
+	return 0;
+}
+EXPORT_SYMBOL_GPL(amd_mp2_read);
+
+int amd_mp2_write(struct pci_dev *dev, struct i2c_config i2c_cfg)
+{
+	struct amd_mp2_dev *privdata = pci_get_drvdata(dev);
+	union i2c_cmd_base i2c_cmd_base;
+	int i = 0;
+
+	privdata->requested = true;
+	dev_dbg(ndev_dev(privdata), "%s addr: %x id: %d\n", __func__,
+		i2c_cfg.dev_addr, i2c_cfg.bus_id);
+
+	i2c_cmd_base.ul = 0;
+	i2c_cmd_base.s.i2c_cmd = i2c_write;
+	i2c_cmd_base.s.dev_addr = i2c_cfg.dev_addr;
+	i2c_cmd_base.s.length = i2c_cfg.length;
+	i2c_cmd_base.s.bus_id = i2c_cfg.bus_id;
+
+	switch (i2c_cfg.i2c_speed) {
+	case 0:
+		i2c_cmd_base.s.i2c_speed = speed100k;
+		break;
+	case 1:
+		i2c_cmd_base.s.i2c_speed = speed400k;
+		break;
+	case 2:
+		i2c_cmd_base.s.i2c_speed = speed1000k;
+		break;
+	case 3:
+		i2c_cmd_base.s.i2c_speed = speed1400k;
+		break;
+	case 4:
+		i2c_cmd_base.s.i2c_speed = speed3400k;
+		break;
+	default:
+		dev_err(ndev_dev(privdata), "Invalid ConnectionSpeed\n");
+	}
+
+	if (i2c_cfg.length <= 32) {
+		i2c_cmd_base.s.mem_type = use_c2pmsg;
+		for (i = 0; i < ((i2c_cfg.length + 3) / 4); i++) {
+			writel(i2c_cfg.write_buf[i],
+			       privdata->mmio + (AMD_C2P_MSG2 + i * 4));
+		}
+	} else {
+		i2c_cmd_base.s.mem_type = use_dram;
+		privdata->i2c_cfg.phy_addr = i2c_cfg.phy_addr;
+		write64((u64)privdata->i2c_cfg.phy_addr,
+			privdata->mmio + AMD_C2P_MSG2);
+	}
+
+	if (i2c_cmd_base.s.bus_id == i2c_bus_1) {
+		writel(i2c_cmd_base.ul, privdata->mmio + AMD_C2P_MSG1);
+	} else if (i2c_cmd_base.s.bus_id == i2c_bus_0) {
+		writel(i2c_cmd_base.ul, privdata->mmio + AMD_C2P_MSG0);
+	} else {
+		dev_err(ndev_dev(privdata), "%s Invalid bus id\n", __func__);
+		return -EINVAL;
+	}
+
+	return 0;
+}
+EXPORT_SYMBOL_GPL(amd_mp2_write);
+
+int amd_i2c_register_cb(struct pci_dev *dev, const struct amd_i2c_pci_ops *ops,
+			void *dev_ctx)
+{
+	struct amd_mp2_dev *privdata = pci_get_drvdata(dev);
+
+	privdata->ops = ops;
+	privdata->i2c_dev_ctx = dev_ctx;
+
+	if (!privdata->ops || !privdata->i2c_dev_ctx)
+		return -EINVAL;
+
+	return 0;
+}
+EXPORT_SYMBOL_GPL(amd_i2c_register_cb);
+
+static void amd_mp2_pci_work(struct work_struct *work)
+{
+	struct amd_mp2_dev *privdata = mp2_dev(work);
+	u32 readdata = 0;
+	int i = 0;
+	int sts = privdata->eventval.base.r.status;
+	int res = privdata->eventval.base.r.response;
+	int len = privdata->eventval.base.r.length;
+
+	if (res == command_success && sts == i2c_readcomplete_event) {
+		if (privdata->ops->read_complete) {
+			if (len <= 32) {
+				for (i = 0; i < ((len + 3) / 4); i++) {
+					readdata = readl(privdata->mmio +
+							(AMD_C2P_MSG2 + i * 4));
+					privdata->eventval.buf[i] = readdata;
+				}
+				privdata->ops->read_complete(privdata->eventval,
+						privdata->i2c_dev_ctx);
+			} else {
+				privdata->ops->read_complete(privdata->eventval,
+						privdata->i2c_dev_ctx);
+			}
+		}
+	} else if (res == command_success && sts == i2c_writecomplete_event) {
+		if (privdata->ops->write_complete)
+			privdata->ops->write_complete(privdata->eventval,
+					privdata->i2c_dev_ctx);
+	} else if (res == command_success && sts == i2c_busenable_complete) {
+		if (privdata->ops->connect_complete)
+			privdata->ops->connect_complete(privdata->eventval,
+					privdata->i2c_dev_ctx);
+	} else {
+		dev_err(ndev_dev(privdata), "ERROR!!nothing to be handled !\n");
+	}
+}
+
+static irqreturn_t amd_mp2_irq_isr(int irq, void *dev)
+{
+	struct amd_mp2_dev *privdata = dev;
+	u32 val = 0;
+	unsigned long  flags;
+
+	raw_spin_lock_irqsave(&privdata->lock, flags);
+	val = readl(privdata->mmio + AMD_P2C_MSG1);
+	if (val != 0) {
+		writel(0, privdata->mmio + AMD_P2C_MSG_INTEN);
+		privdata->eventval.base.ul = val;
+	} else {
+		val = readl(privdata->mmio + AMD_P2C_MSG2);
+		if (val != 0) {
+			writel(0, privdata->mmio + AMD_P2C_MSG_INTEN);
+			privdata->eventval.base.ul = val;
+		}
+	}
+
+	raw_spin_unlock_irqrestore(&privdata->lock, flags);
+	if (!privdata->ops)
+		return IRQ_NONE;
+
+	if (!privdata->requested)
+		return IRQ_HANDLED;
+
+	privdata->requested = false;
+	schedule_delayed_work(&privdata->work, 0);
+
+	return IRQ_HANDLED;
+}
+
+static ssize_t amd_mp2_debugfs_read(struct file *filp, char __user *ubuf,
+				    size_t count, loff_t *offp)
+{
+	struct amd_mp2_dev *privdata;
+	void __iomem *mmio;
+	u8 *buf;
+	u32 data;
+	size_t buf_size;
+	ssize_t ret, off;
+
+	privdata = filp->private_data;
+	mmio = privdata->mmio;
+	buf_size = min(count, 0x800ul);
+	buf = kmalloc(buf_size, GFP_KERNEL);
+
+	if (!buf)
+		return -ENOMEM;
+
+	off = 0;
+	off += scnprintf(buf + off, buf_size - off,
+			"Mp2 Device Information:\n");
+
+	off += scnprintf(buf + off, buf_size - off,
+			"========================\n");
+	off += scnprintf(buf + off, buf_size - off,
+			"\tMP2 C2P Message Register Dump:\n\n");
+	data = readl(privdata->mmio + AMD_C2P_MSG0);
+	off += scnprintf(buf + off, buf_size - off,
+			"AMD_C2P_MSG0 -\t\t\t%#06x\n", data);
+
+	data = readl(privdata->mmio + AMD_C2P_MSG1);
+	off += scnprintf(buf + off, buf_size - off,
+			"AMD_C2P_MSG1 -\t\t\t%#06x\n", data);
+
+	data = readl(privdata->mmio + AMD_C2P_MSG2);
+	off += scnprintf(buf + off, buf_size - off,
+			"AMD_C2P_MSG2 -\t\t\t%#06x\n", data);
+
+	data = readl(privdata->mmio + AMD_C2P_MSG3);
+	off += scnprintf(buf + off, buf_size - off,
+			"AMD_C2P_MSG3 -\t\t\t%#06x\n", data);
+
+	data = readl(privdata->mmio + AMD_C2P_MSG4);
+	off += scnprintf(buf + off, buf_size - off,
+			"AMD_C2P_MSG4 -\t\t\t%#06x\n", data);
+
+	data = readl(privdata->mmio + AMD_C2P_MSG5);
+	off += scnprintf(buf + off, buf_size - off,
+			"AMD_C2P_MSG5 -\t\t\t%#06x\n", data);
+
+	data = readl(privdata->mmio + AMD_C2P_MSG6);
+	off += scnprintf(buf + off, buf_size - off,
+			"AMD_C2P_MSG6 -\t\t\t%#06x\n", data);
+
+	data = readl(privdata->mmio + AMD_C2P_MSG7);
+	off += scnprintf(buf + off, buf_size - off,
+			"AMD_C2P_MSG7 -\t\t\t%#06x\n", data);
+
+	data = readl(privdata->mmio + AMD_C2P_MSG8);
+	off += scnprintf(buf + off, buf_size - off,
+			"AMD_C2P_MSG8 -\t\t\t%#06x\n", data);
+
+	data = readl(privdata->mmio + AMD_C2P_MSG9);
+	off += scnprintf(buf + off, buf_size - off,
+			"AMD_C2P_MSG9 -\t\t\t%#06x\n", data);
+
+	off += scnprintf(buf + off, buf_size - off,
+			"\n\tMP2 P2C Message Register Dump:\n\n");
+
+	data = readl(privdata->mmio + AMD_P2C_MSG1);
+	off += scnprintf(buf + off, buf_size - off,
+			"AMD_P2C_MSG1 -\t\t\t%#06x\n", data);
+
+	data = readl(privdata->mmio + AMD_P2C_MSG2);
+	off += scnprintf(buf + off, buf_size - off,
+			"AMD_P2C_MSG2 -\t\t\t%#06x\n", data);
+
+	data = readl(privdata->mmio + AMD_P2C_MSG_INTEN);
+	off += scnprintf(buf + off, buf_size - off,
+			"AMD_P2C_MSG_INTEN -\t\t%#06x\n", data);
+
+	data = readl(privdata->mmio + AMD_P2C_MSG_INTSTS);
+	off += scnprintf(buf + off, buf_size - off,
+			"AMD_P2C_MSG_INTSTS -\t\t%#06x\n", data);
+
+	ret = simple_read_from_buffer(ubuf, count, offp, buf, off);
+	kfree(buf);
+	return ret;
+}
+
+static void amd_mp2_init_debugfs(struct amd_mp2_dev *privdata)
+{
+	if (!debugfs_dir) {
+		privdata->debugfs_dir = NULL;
+		privdata->debugfs_info = NULL;
+	} else {
+		privdata->debugfs_dir = debugfs_create_dir(ndev_name(privdata),
+							   debugfs_dir);
+		if (!privdata->debugfs_dir) {
+			privdata->debugfs_info = NULL;
+		} else {
+			privdata->debugfs_info = debugfs_create_file
+				("info", 0400, privdata->debugfs_dir,
+					privdata, &amd_mp2_debugfs_info);
+		}
+	}
+}
+
+static void amd_mp2_deinit_debugfs(struct amd_mp2_dev *privdata)
+{
+	debugfs_remove_recursive(privdata->debugfs_dir);
+}
+
+static void amd_mp2_clear_reg(struct amd_mp2_dev *privdata)
+{
+	int reg = 0;
+
+	for (reg = AMD_C2P_MSG0; reg <= AMD_C2P_MSG9; reg += 4)
+		writel(0, privdata->mmio + reg);
+
+	for (reg = AMD_P2C_MSG0; reg <= AMD_P2C_MSG2; reg += 4)
+		writel(0, privdata->mmio + reg);
+}
+
+static int amd_mp2_pci_init(struct amd_mp2_dev *privdata, struct pci_dev *pdev)
+{
+	int rc;
+	int bar_index = 2;
+	resource_size_t size, base;
+
+	pci_set_drvdata(pdev, privdata);
+
+	rc = pci_enable_device(pdev);
+	if (rc)
+		goto err_pci_enable;
+
+	rc = pci_request_regions(pdev, DRIVER_NAME);
+	if (rc)
+		goto err_pci_regions;
+
+	pci_set_master(pdev);
+
+	rc = pci_set_dma_mask(pdev, DMA_BIT_MASK(64));
+	if (rc) {
+		rc = pci_set_dma_mask(pdev, DMA_BIT_MASK(32));
+		if (rc)
+			goto err_dma_mask;
+		dev_warn(ndev_dev(privdata), "Cannot DMA highmem\n");
+	}
+
+	rc = pci_set_consistent_dma_mask(pdev, DMA_BIT_MASK(64));
+	if (rc) {
+		rc = pci_set_consistent_dma_mask(pdev, DMA_BIT_MASK(32));
+		if (rc)
+			goto err_dma_mask;
+		dev_warn(ndev_dev(privdata), "Cannot DMA consistent highmem\n");
+	}
+
+	base = pci_resource_start(pdev, bar_index);
+	size = pci_resource_len(pdev, bar_index);
+
+	privdata->mmio = ioremap(base, size);
+	if (!privdata->mmio) {
+		rc = -EIO;
+		goto err_dma_mask;
+	}
+
+	/* Try to set up intx irq */
+	pci_intx(pdev, 1);
+	privdata->eventval.buf = NULL;
+	privdata->requested = false;
+	raw_spin_lock_init(&privdata->lock);
+	rc = request_irq(pdev->irq, amd_mp2_irq_isr, IRQF_SHARED, "mp2_irq_isr",
+			 privdata);
+	if (rc)
+		goto err_intx_request;
+
+	return 0;
+
+err_intx_request:
+	return rc;
+err_dma_mask:
+	pci_clear_master(pdev);
+	pci_release_regions(pdev);
+err_pci_regions:
+	pci_disable_device(pdev);
+err_pci_enable:
+	pci_set_drvdata(pdev, NULL);
+	return rc;
+}
+
+static void amd_mp2_pci_deinit(struct amd_mp2_dev *privdata)
+{
+	struct pci_dev *pdev = ndev_pdev(privdata);
+
+	pci_iounmap(pdev, privdata->mmio);
+
+	pci_clear_master(pdev);
+	pci_release_regions(pdev);
+	pci_disable_device(pdev);
+	pci_set_drvdata(pdev, NULL);
+}
+
+static int amd_mp2_pci_probe(struct pci_dev *pdev,
+			     const struct pci_device_id *id)
+{
+	struct amd_mp2_dev *privdata;
+	int rc;
+
+	dev_info(&pdev->dev, "MP2 device found [%04x:%04x] (rev %x)\n",
+		 (int)pdev->vendor, (int)pdev->device, (int)pdev->revision);
+
+	privdata = kzalloc(sizeof(*privdata), GFP_KERNEL);
+	privdata->pdev = pdev;
+
+	if (!privdata) {
+		rc = -ENOMEM;
+		goto err_dev;
+	}
+
+	rc = amd_mp2_pci_init(privdata, pdev);
+	if (rc)
+		goto err_pci_init;
+	dev_dbg(&pdev->dev, "pci init done.\n");
+
+	INIT_DELAYED_WORK(&privdata->work, amd_mp2_pci_work);
+
+	amd_mp2_init_debugfs(privdata);
+	dev_info(&pdev->dev, "MP2 device registered.\n");
+	return 0;
+
+err_pci_init:
+	kfree(privdata);
+err_dev:
+	dev_err(&pdev->dev, "Memory Allocation Failed\n");
+	return rc;
+}
+
+static void amd_mp2_pci_remove(struct pci_dev *pdev)
+{
+	struct amd_mp2_dev *privdata = pci_get_drvdata(pdev);
+
+	amd_mp2_deinit_debugfs(privdata);
+	amd_mp2_clear_reg(privdata);
+	cancel_delayed_work_sync(&privdata->work);
+	free_irq(pdev->irq, privdata);
+	pci_intx(pdev, 0);
+	amd_mp2_pci_deinit(privdata);
+	kfree(privdata);
+}
+
+static const struct file_operations amd_mp2_debugfs_info = {
+	.owner = THIS_MODULE,
+	.open = simple_open,
+	.read = amd_mp2_debugfs_read,
+};
+
+static const struct pci_device_id amd_mp2_pci_tbl[] = {
+	{PCI_VDEVICE(AMD, PCI_DEVICE_ID_AMD_MP2)},
+	{0}
+};
+MODULE_DEVICE_TABLE(pci, amd_mp2_pci_tbl);
+
+#ifdef CONFIG_PM_SLEEP
+static int amd_mp2_pci_device_suspend(struct pci_dev *pdev, pm_message_t mesg)
+{
+	struct amd_mp2_dev *privdata = pci_get_drvdata(pdev);
+
+	if (!privdata)
+		return -EINVAL;
+
+	return 0;
+}
+
+static int amd_mp2_pci_device_resume(struct pci_dev *pdev)
+{
+	struct amd_mp2_dev *privdata = pci_get_drvdata(pdev);
+
+	if (!privdata)
+		return -EINVAL;
+
+	return 0;
+}
+#endif
+
+static struct pci_driver amd_mp2_pci_driver = {
+	.name		= DRIVER_NAME,
+	.id_table	= amd_mp2_pci_tbl,
+	.probe		= amd_mp2_pci_probe,
+	.remove		= amd_mp2_pci_remove,
+#ifdef CONFIG_PM_SLEEP
+	.suspend		= amd_mp2_pci_device_suspend,
+	.resume			= amd_mp2_pci_device_resume,
+#endif
+};
+
+static int __init amd_mp2_pci_driver_init(void)
+{
+	pr_info("%s: %s Version: %s\n", DRIVER_NAME, DRIVER_DESC, DRIVER_VER);
+
+	if (debugfs_initialized())
+		debugfs_dir = debugfs_create_dir(KBUILD_MODNAME, NULL);
+
+	return pci_register_driver(&amd_mp2_pci_driver);
+}
+module_init(amd_mp2_pci_driver_init);
+
+static void __exit amd_mp2_pci_driver_exit(void)
+{
+	pci_unregister_driver(&amd_mp2_pci_driver);
+	debugfs_remove_recursive(debugfs_dir);
+}
+module_exit(amd_mp2_pci_driver_exit);
diff --git a/drivers/i2c/busses/i2c-amd-pci-mp2.h b/drivers/i2c/busses/i2c-amd-pci-mp2.h
new file mode 100644
index 0000000..787484e
--- /dev/null
+++ b/drivers/i2c/busses/i2c-amd-pci-mp2.h
@@ -0,0 +1,196 @@ 
+/* SPDX-License-Identifier: GPL-2.0
+ *
+ * Copyright (C) 2018 Advanced Micro Devices, Inc. All Rights Reserved
+ *
+ * Author: Shyam Sundar S K <Shyam-sundar.S-k@amd.com>
+ * AMD PCIe MP2 Communication Interface Driver
+ */
+
+#ifndef I2C_AMD_PCI_MP2_H
+#define I2C_AMD_PCI_MP2_H
+
+#include <linux/pci.h>
+
+#define PCI_DEVICE_ID_AMD_MP2	0x15E6
+
+#define write64 _write64
+static inline void _write64(u64 val, void __iomem *mmio)
+{
+	writel(val, mmio);
+	writel(val >> 32, mmio + sizeof(u32));
+}
+
+#define read64 _read64
+static inline u64 _read64(void __iomem *mmio)
+{
+	u64 low, high;
+
+	low = readl(mmio);
+	high = readl(mmio + sizeof(u32));
+	return low | (high << 32);
+}
+
+enum {
+	/* MP2 C2P Message Registers */
+	AMD_C2P_MSG0 = 0x10500, /*MP2 Message for I2C0*/
+	AMD_C2P_MSG1 = 0x10504, /*MP2 Message for I2C1*/
+	AMD_C2P_MSG2 = 0x10508, /*DRAM Address Lo / Data 0*/
+	AMD_C2P_MSG3 = 0x1050c, /*DRAM Address HI / Data 1*/
+	AMD_C2P_MSG4 = 0x10510, /*Data 2*/
+	AMD_C2P_MSG5 = 0x10514, /*Data 3*/
+	AMD_C2P_MSG6 = 0x10518, /*Data 4*/
+	AMD_C2P_MSG7 = 0x1051c, /*Data 5*/
+	AMD_C2P_MSG8 = 0x10520, /*Data 6*/
+	AMD_C2P_MSG9 = 0x10524, /*Data 7*/
+
+	/* MP2 P2C Message Registers */
+	AMD_P2C_MSG0 = 0x10680, /*Do not use*/
+	AMD_P2C_MSG1 = 0x10684, /*I2c0 int reg*/
+	AMD_P2C_MSG2 = 0x10688, /*I2c1 int reg*/
+	AMD_P2C_MSG3 = 0x1068C, /*MP2 debug info*/
+	AMD_P2C_MSG_INTEN = 0x10690, /*MP2 int gen register*/
+	AMD_P2C_MSG_INTSTS = 0x10694, /*Interrupt sts*/
+};
+
+/* Command register data structures */
+
+enum i2c_cmd {
+	i2c_read,
+	i2c_write,
+	i2c_enable,
+	i2c_disable,
+	number_of_sensor_discovered,
+	is_mp2_active,
+	invalid_cmd = 0xF,
+};
+
+enum i2c_bus_index {
+	i2c_bus_0 = 0,
+	i2c_bus_1 = 1,
+	i2c_bus_max
+};
+
+enum speed_enum {
+	speed100k = 0,
+	speed400k = 1,
+	speed1000k = 2,
+	speed1400k = 3,
+	speed3400k = 4
+};
+
+enum mem_type {
+	use_dram = 0,
+	use_c2pmsg = 1,
+};
+
+union i2c_cmd_base {
+	u32 ul;
+	struct {
+		enum i2c_cmd i2c_cmd : 4; /*!< bit: 0..3 i2c R/W command */
+		enum i2c_bus_index bus_id : 4; /*!< bit: 4..7 i2c bus index */
+		u32 dev_addr : 8; /*!< bit: 8..15 device address or Bus Speed*/
+		u32 length : 12; /*!< bit: 16..29 read/write length */
+		enum speed_enum i2c_speed : 3; /*!< bit: 30 register address*/
+		enum mem_type mem_type : 1; /*!< bit: 15 mem type*/
+	} s; /*!< Structure used for bit access */
+};
+
+/* Response register data structures */
+
+/*Response - Response of SFI*/
+enum response_type {
+	invalid_response = 0,
+	command_success = 1,
+	command_failed = 2,
+};
+
+/*Status - Command ID to indicate a command*/
+enum status_type {
+	i2c_readcomplete_event = 0,
+	i2c_readfail_event = 1,
+	i2c_writecomplete_event = 2,
+	i2c_writefail_event = 3,
+	i2c_busenable_complete = 4,
+	i2c_busenable_failed = 5,
+	i2c_busdisable_complete = 6,
+	i2c_busdisable_failed = 7,
+	invalid_data_length = 8,
+	invalid_slave_address = 9,
+	invalid_i2cbus_id = 10,
+	invalid_dram_addr = 11,
+	invalid_command = 12,
+	mp2_active = 13,
+	numberof_sensors_discovered_resp = 14,
+	i2C_bus_notinitialized
+};
+
+struct i2c_event {
+	union {
+		u32 ul;
+		struct {
+			enum response_type response : 2; /*!< bit: 0..1 I2C res type */
+			enum status_type status : 5; /*!< bit: 2..6 status_type */
+			enum mem_type mem_type : 1; /*!< bit: 7 0-DRAM;1- C2PMsg o/p */
+			enum i2c_bus_index bus_id : 4; /*!< bit: 8..11 I2C Bus ID */
+			u32 length : 12; /*!< bit:16..29 length */
+			u32 slave_addr : 8; /*!< bit: 15 debug msg include in p2c msg */
+		} r; /*!< Structure used for bit access */
+	} base;
+	u32 *buf;
+};
+
+/* data structures for communication with I2c*/
+
+struct i2c_config {
+	enum i2c_bus_index bus_id;
+	u64 i2c_speed;
+	u16 dev_addr;
+	u32 length;
+	phys_addr_t phy_addr;
+	u8 *read_buf;
+	u32 *write_buf;
+};
+
+/* struct to send/receive data b/w pci and i2c drivers*/
+struct amd_i2c_pci_ops {
+	int (*read_complete)(struct i2c_event event, void *dev_ctx);
+	int (*write_complete)(struct i2c_event event, void *dev_ctx);
+	int (*connect_complete)(struct i2c_event event, void *dev_ctx);
+};
+
+struct amd_i2c_common {
+	struct i2c_config i2c_cfg;
+	const struct amd_i2c_pci_ops *ops;
+	struct pci_dev *pdev;
+};
+
+struct amd_mp2_dev {
+	struct pci_dev *pdev;
+	struct dentry *debugfs_dir;
+	struct dentry *debugfs_info;
+	void __iomem *mmio;
+	struct i2c_event eventval;
+	enum i2c_cmd reqcmd;
+	struct i2c_config i2c_cfg;
+	union i2c_cmd_base i2c_cmd_base;
+	const struct amd_i2c_pci_ops *ops;
+	struct delayed_work work;
+	void *i2c_dev_ctx;
+	bool requested;
+	raw_spinlock_t lock;
+};
+
+int amd_mp2_read(struct pci_dev *pdev, struct i2c_config i2c_cfg);
+int amd_mp2_write(struct pci_dev *pdev,
+		  struct i2c_config i2c_cfg);
+int amd_mp2_connect(struct pci_dev *pdev,
+		    struct i2c_config i2c_cfg);
+int amd_i2c_register_cb(struct pci_dev *pdev, const struct amd_i2c_pci_ops *ops,
+			void *dev_ctx);
+
+#define ndev_pdev(ndev) ((ndev)->pdev)
+#define ndev_name(ndev) pci_name(ndev_pdev(ndev))
+#define ndev_dev(ndev) (&ndev_pdev(ndev)->dev)
+#define mp2_dev(__work) container_of(__work, struct amd_mp2_dev, work.work)
+
+#endif
diff --git a/drivers/i2c/busses/i2c-amd-platdrv.c b/drivers/i2c/busses/i2c-amd-platdrv.c
new file mode 100644
index 0000000..95e3b37
--- /dev/null
+++ b/drivers/i2c/busses/i2c-amd-platdrv.c
@@ -0,0 +1,277 @@ 
+// SPDX-License-Identifier: GPL-2.0
+/*
+ *
+ * Copyright (C) 2018 Advanced Micro Devices, Inc. All Rights Reserved.
+ *
+ *
+ * Author: Nehal Bakulchandra Shah <Nehal-bakulchandra.shah@amd.com>
+ * AMD I2C Platform Driver
+ */
+
+#include <linux/kernel.h>
+#include <linux/module.h>
+#include <linux/types.h>
+#include <linux/slab.h>
+#include <linux/i2c.h>
+#include <linux/platform_device.h>
+#include <linux/dma-mapping.h>
+#include <linux/acpi.h>
+#include <linux/delay.h>
+#include "i2c-amd-pci-mp2.h"
+
+struct amd_i2c_dev {
+	struct platform_device *pdev;
+	struct i2c_adapter adapter;
+	struct amd_i2c_common i2c_common;
+	struct completion msg_complete;
+	struct i2c_msg *msg_buf;
+	bool is_configured;
+	u8 bus_id;
+	u8 *buf;
+};
+
+static int i2c_amd_read_completion(struct i2c_event event, void *dev_ctx)
+{
+	struct amd_i2c_dev *i2c_dev = (struct amd_i2c_dev *)dev_ctx;
+	struct amd_i2c_common *commond = &i2c_dev->i2c_common;
+	int i = 0;
+
+	if (event.base.r.status == i2c_readcomplete_event) {
+		if (event.base.r.length <= 32) {
+			pr_devel(" in %s i2c_dev->msg_buf :%p\n",
+				 __func__, i2c_dev->msg_buf);
+
+			memcpy(i2c_dev->msg_buf->buf,
+			       (unsigned char *)event.buf, event.base.r.length);
+
+			for (i = 0; i < ((event.base.r.length + 3) / 4); i++)
+				pr_devel("%s: readdata:%x\n",
+					 __func__, event.buf[i]);
+
+		} else {
+			memcpy(i2c_dev->msg_buf->buf,
+			       (unsigned char *)commond->i2c_cfg.read_buf,
+				event.base.r.length);
+
+			for (i = 0; i < ((event.base.r.length + 3) / 4); i++)
+				pr_devel("%s: readdata:%x\n", __func__,
+					 ((unsigned int *)commond->i2c_cfg.read_buf)[i]);
+		}
+
+				complete(&i2c_dev->msg_complete);
+	}
+
+	return 0;
+}
+
+static int i2c_amd_write_completion(struct i2c_event event, void *dev_ctx)
+{
+	struct amd_i2c_dev *i2c_dev = (struct amd_i2c_dev *)dev_ctx;
+
+	if (event.base.r.status == i2c_writecomplete_event)
+			complete(&i2c_dev->msg_complete);
+
+	return 0;
+}
+
+static int i2c_amd_connect_completion(struct i2c_event event, void *dev_ctx)
+{
+	struct amd_i2c_dev *i2c_dev = (struct amd_i2c_dev *)dev_ctx;
+
+	if (event.base.r.status == i2c_busenable_complete)
+			complete(&i2c_dev->msg_complete);
+
+	return 0;
+}
+
+static const struct amd_i2c_pci_ops data_handler = {
+		.read_complete = i2c_amd_read_completion,
+		.write_complete = i2c_amd_write_completion,
+		.connect_complete = i2c_amd_connect_completion,
+};
+
+static int i2c_amd_pci_configure(struct amd_i2c_dev *i2c_dev, int slaveaddr)
+{
+	struct amd_i2c_common *i2c_common = &i2c_dev->i2c_common;
+	int ret;
+
+	amd_i2c_register_cb(i2c_common->pdev, &data_handler, (void *)i2c_dev);
+	i2c_common->i2c_cfg.bus_id = i2c_dev->bus_id;
+	i2c_common->i2c_cfg.dev_addr = slaveaddr;
+	i2c_common->i2c_cfg.i2c_speed = speed400k;
+	ret = amd_mp2_connect(i2c_common->pdev, i2c_common->i2c_cfg);
+
+	if (ret)
+		return	-EIO;
+
+	mdelay(100);
+
+	return 0;
+}
+
+static int i2c_amd_xfer(struct i2c_adapter *adap, struct i2c_msg *msgs, int num)
+{
+	struct amd_i2c_dev *dev = i2c_get_adapdata(adap);
+	struct amd_i2c_common *i2c_common = &dev->i2c_common;
+
+	int i;
+	unsigned long timeout;
+	struct i2c_msg *pmsg;
+	unsigned char *dma_buf = NULL;
+	dma_addr_t phys;
+
+	reinit_completion(&dev->msg_complete);
+	if (dev->is_configured == 0) {
+		i2c_amd_pci_configure(dev, msgs->addr);
+		timeout = wait_for_completion_timeout(&dev->msg_complete, 50);
+		dev->is_configured = 1;
+	}
+
+	for (i = 0; i < num; i++) {
+		pmsg = &msgs[i];
+		i2c_common->i2c_cfg.length = pmsg->len;
+		if (pmsg->len > 32) {
+			dma_buf = (u8 *)dma_alloc_coherent(&i2c_common->pdev->dev,
+					pmsg->len, &phys, GFP_KERNEL);
+			i2c_common->i2c_cfg.phy_addr = phys;
+		}
+
+		if (pmsg->flags & I2C_M_RD) {
+			if (pmsg->len <= 32)
+				i2c_common->i2c_cfg.read_buf = dev->buf;
+			else
+				i2c_common->i2c_cfg.read_buf = dma_buf;
+
+			dev->msg_buf = pmsg;
+			amd_mp2_read(i2c_common->pdev,
+				     i2c_common->i2c_cfg);
+
+		} else {
+			if (pmsg->len <= 32)
+				i2c_common->i2c_cfg.write_buf = (unsigned int *)pmsg->buf;
+			else
+				i2c_common->i2c_cfg.write_buf = (unsigned int *)dma_buf;
+
+			amd_mp2_write(i2c_common->pdev,
+				      i2c_common->i2c_cfg);
+		}
+
+		timeout = wait_for_completion_timeout
+					(&dev->msg_complete, 50);
+		if (dma_buf)
+			dma_free_coherent(&i2c_common->pdev->dev,
+					  pmsg->len, dma_buf, phys);
+
+		if (timeout == 0)
+			return -ETIMEDOUT;
+	}
+	return num;
+}
+
+static u32 i2c_amd_func(struct i2c_adapter *a)
+{
+	return I2C_FUNC_I2C;
+}
+
+static const struct i2c_algorithm i2c_amd_algorithm = {
+	.master_xfer = i2c_amd_xfer,
+	.functionality = i2c_amd_func,
+};
+
+static int i2c_amd_probe(struct platform_device *pdev)
+{
+	int ret;
+	struct amd_i2c_dev *i2c_dev;
+	struct device *dev = &pdev->dev;
+	acpi_handle handle = ACPI_HANDLE(&pdev->dev);
+	struct acpi_device *adev;
+	const char *uid = NULL;
+
+	i2c_dev = devm_kzalloc(dev, sizeof(*i2c_dev), GFP_KERNEL);
+	if (!i2c_dev)
+		return -ENOMEM;
+
+	i2c_dev->pdev = pdev;
+
+	if (!acpi_bus_get_device(handle, &adev)) {
+		pr_err(" i2c0  pdev->id=%s\n", adev->pnp.unique_id);
+		uid = adev->pnp.unique_id;
+	}
+
+	if (strcmp(uid, "0") == 0) {
+		pr_err(" bus id is 0\n");
+		i2c_dev->bus_id = 0;
+	}
+
+	pr_devel(" i2c1  pdev->id=%s\n", uid);
+	if (strcmp(uid, "1") == 0) {
+		pr_err(" bus id is 1\n");
+		i2c_dev->bus_id = 1;
+	}
+	/* setup i2c adapter description */
+	i2c_dev->adapter.owner = THIS_MODULE;
+	i2c_dev->adapter.algo = &i2c_amd_algorithm;
+	i2c_dev->adapter.dev.parent = dev;
+	i2c_dev->adapter.algo_data = i2c_dev;
+	ACPI_COMPANION_SET(&i2c_dev->adapter.dev, ACPI_COMPANION(&pdev->dev));
+	i2c_dev->adapter.dev.of_node = dev->of_node;
+	/*buffer for 32 bytes of read  data*/
+	i2c_dev->buf = kzalloc(32, GFP_KERNEL);
+
+	if (!i2c_dev->buf)
+		return -ENOMEM;
+
+	snprintf(i2c_dev->adapter.name, sizeof(i2c_dev->adapter.name), "%s-%s",
+		 "i2c_dev-i2c", dev_name(pdev->dev.parent));
+
+	i2c_dev->i2c_common.pdev = pci_get_device(PCI_VENDOR_ID_AMD,
+						  PCI_DEVICE_ID_AMD_MP2, NULL);
+
+	if (!i2c_dev->i2c_common.pdev) {
+		pr_err("%s Could not find pdev in i2c\n", __func__);
+		return -EINVAL;
+	}
+	platform_set_drvdata(pdev, i2c_dev);
+	i2c_set_adapdata(&i2c_dev->adapter, i2c_dev);
+
+	init_completion(&i2c_dev->msg_complete);
+	/* and finally attach to i2c layer */
+	ret = i2c_add_adapter(&i2c_dev->adapter);
+
+	if (ret < 0)
+		pr_err(" i2c add adpater failed =%d", ret);
+
+	return ret;
+}
+
+static int i2c_amd_remove(struct platform_device *pdev)
+{
+	struct amd_i2c_dev *i2c_dev = platform_get_drvdata(pdev);
+
+	kfree(i2c_dev->buf);
+
+	i2c_del_adapter(&i2c_dev->adapter);
+
+	return 0;
+}
+
+static const struct acpi_device_id i2c_amd_acpi_match[] = {
+		{ "AMDI0011" },
+		{ },
+};
+
+static struct platform_driver amd_i2c_plat_driver = {
+		.probe = i2c_amd_probe,
+		.remove = i2c_amd_remove,
+		.driver = {
+				.name = "i2c_amd_platdrv",
+				.acpi_match_table = ACPI_PTR
+						(i2c_amd_acpi_match),
+		},
+};
+
+module_platform_driver(amd_i2c_plat_driver);
+
+MODULE_AUTHOR("Nehal Shah <nehal-bakulchandra.shah@amd.com>");
+MODULE_DESCRIPTION("AMD I2C Platform Driver");
+MODULE_LICENSE("Dual BSD/GPL");