[PATCH 1/4] UBUNTU: SAUCE: i2c:amd I2C Driver based on PCI Interface for upcoming platform

Kai Heng Feng kai.heng.feng at canonical.com
Wed Aug 22 07:32:43 UTC 2018


> On Jul 31, 2018, at 8:40 PM, Stefan Bader <stefan.bader at canonical.com>  
> wrote:
>
> On 19.07.2018 12:19, Kai-Heng Feng wrote:
>> From: Nehal-bakulchandra Shah <Nehal-bakulchandra.Shah at amd.com>
>>
>> BugLink: https://bugs.launchpad.net/bugs/1773940
>>
>> Added fix for suspend resume and touchpad lost issue
>> Added fix for IOMMU
>> 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 at amd.com>
>> Reviewed-by: Sandeep Singh <sandeep.singh at amd.com>
>> Signed-off-by: Nehal-bakulchandra Shah <Nehal-bakulchandra.Shah at amd.com>
>> Signed-off-by: Kai-Heng Feng <kai.heng.feng at canonical.com>
>> ---
>>  drivers/i2c/busses/Kconfig           |  10 +
>>  drivers/i2c/busses/Makefile          |   2 +
>>  drivers/i2c/busses/i2c-amd-pci-mp2.c | 626 +++++++++++++++++++++++++++
>>  drivers/i2c/busses/i2c-amd-pci-mp2.h | 251 +++++++++++
>>  drivers/i2c/busses/i2c-amd-platdrv.c | 332 ++++++++++++++
>>  5 files changed, 1221 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 033958bcdd4b..8a623b9824c9 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 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.
>
> I really don't like the fact that it is claiming to be buildable as a  
> module but
> not working that way. It makes me even less confident that I would like  
> to have
> the whole thing built-in. Have you tried the changes to Makefile below?  
> Config
> help would then have to say: "will be called i2c-amd-mp2."

Ok, I found the reason why it needs to be builtin:
The MP2 driver itself as module does work, but if we want the i2c touchpad  
uses it as transport, the MP2 driver has to be loaded before i2c-hid gets  
probed.
Unfortunately both of them uses ACPI device ID to match, so the i2c-hid may  
get loaded before MP2.
AFAIK, there's no good way to guarantee the module loading ordering, so  
make MP2 builtin is the only approach I can think of.
That's also the reason why several drivers use APCI ID in drivers/pinctrl  
and drivers/gpio are set to "=y".

>
>> +
>>  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 d6e48ec3372a..5bcc1a732dd0 100644
>> --- a/drivers/i2c/busses/Makefile
>> +++ b/drivers/i2c/busses/Makefile
>> @@ -115,6 +115,8 @@ 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
>
> Instead of the 2 lines above:
>
> i2c-amd-mp2-objs := i2c-amd-pci-mp2.o i2c-amd-platdrv.o
> obj-$(CONFIG_I2C_AMD_MP2)	+= i2c-amd-mp2.o

I've already forwarded all the suggestions to the patch author. Once the v2  
series is in the upstream, I'll drop the SAUCE and update it with upstream  
version.

So please consider including this series.

Kai-Heng

>
>>  # 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 000000000000..2266bf156853
>> --- /dev/null
>> +++ b/drivers/i2c/busses/i2c-amd-pci-mp2.c
>> @@ -0,0 +1,626 @@
>> +// SPDX-License-Identifier: GPL-2.0
>> +/*
>> + * This file is provided under a dual BSD/GPLv2 license.  When using or
>> + *   redistributing this file, you may do so under either license.
>> + *
>> + *   GPL LICENSE SUMMARY
>> + *
>> + *   Copyright (C) 2018 Advanced Micro Devices, Inc. All Rights Reserved.
>> + *
>> + *   This program is free software; you can redistribute it and/or modify
>> + *   it under the terms of version 2 of the GNU General Public License as
>> + *   published by the Free Software Foundation.
>> + *
>> + *   BSD LICENSE
>> + *
>> + *   Copyright (C) 2018 Advanced Micro Devices, Inc. All Rights Reserved.
>> + *
>> + *   Redistribution and use in source and binary forms, with or without
>> + *   modification, are permitted provided that the following conditions
>> + *   are met:
>> + *
>> + *     * Redistributions of source code must retain the above copyright
>> + *       notice, this list of conditions and the following disclaimer.
>> + *     * Redistributions in binary form must reproduce the above copy
>> + *       notice, this list of conditions and the following disclaimer in
>> + *       the documentation and/or other materials provided with the
>> + *       distribution.
>> + *     * Neither the name of AMD Corporation nor the names of its
>> + *       contributors may be used to endorse or promote products derived
>> + *       from this software without specific prior written permission.
>> + *
>> + *   THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
>> + *   "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
>> + *   LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS  
>> FOR
>> + *   A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
>> + *   OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT,  
>> INCIDENTAL,
>> + *   SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
>> + *   LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF  
>> USE,
>> + *   DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON  
>> ANY
>> + *   THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
>> + *   (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE  
>> USE
>> + *   OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
>> + *
>> + * AMD PCIe MP2 Communication Driver
>> + * Author: Shyam Sundar S K <Shyam-sundar.S-k at amd.com>
>> + */
>> +
>> +#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 at 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_connect_config connect_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__,
>> +		connect_cfg.dev_addr, connect_cfg.bus_id);
>> +
>> +	i2c_cmd_base.ul = 0;
>> +	i2c_cmd_base.s.i2c_cmd = i2c_enable;
>> +	i2c_cmd_base.s.bus_id = connect_cfg.bus_id;
>> +	i2c_cmd_base.s.i2c_speed = connect_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_read_config read_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__,
>> +		read_cfg.dev_addr, read_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 = read_cfg.dev_addr;
>> +	i2c_cmd_base.s.length = read_cfg.length;
>> +	i2c_cmd_base.s.bus_id = read_cfg.bus_id;
>> +
>> +	if (read_cfg.length <= 32) {
>> +		i2c_cmd_base.s.mem_type = use_c2pmsg;
>> +		if (!privdata->eventval.buf) {
>> +			dev_err(ndev_dev(privdata), "%s no mem for buf received\n",
>> +				__func__);
>> +			return -ENOMEM;
>> +		}
>> +		privdata->eventval.buf = (u32 *)read_cfg.buf;
>> +		dev_dbg(ndev_dev(privdata), "%s buf: %llx\n", __func__,
>> +			(u64)privdata->eventval.buf);
>> +	} else {
>> +		i2c_cmd_base.s.mem_type = use_dram;
>> +		privdata->read_cfg.phy_addr = read_cfg.phy_addr;
>> +		privdata->read_cfg.buf = read_cfg.buf;
>> +		write64((u64)privdata->read_cfg.phy_addr,
>> +			privdata->mmio + AMD_C2P_MSG2);
>> +	}
>> +
>> +	switch (read_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_write_config write_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__,
>> +		write_cfg.dev_addr, write_cfg.bus_id);
>> +
>> +	i2c_cmd_base.ul = 0;
>> +	i2c_cmd_base.s.i2c_cmd = i2c_write;
>> +	i2c_cmd_base.s.dev_addr = write_cfg.dev_addr;
>> +	i2c_cmd_base.s.length = write_cfg.length;
>> +	i2c_cmd_base.s.bus_id = write_cfg.bus_id;
>> +
>> +	switch (write_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 (write_cfg.length <= 32) {
>> +		i2c_cmd_base.s.mem_type = use_c2pmsg;
>> +		for (i = 0; i < ((write_cfg.length + 3) / 4); i++) {
>> +			writel(write_cfg.buf[i],
>> +			       privdata->mmio + (AMD_C2P_MSG2 + i * 4));
>> +		}
>> +	} else {
>> +		i2c_cmd_base.s.mem_type = use_dram;
>> +		privdata->write_cfg.phy_addr = write_cfg.phy_addr;
>> +		write64((u64)privdata->write_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.r.status;
>> +	int res = privdata->eventval.r.response;
>> +	int len = privdata->eventval.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.ul = val;
>> +	} else {
>> +		val = readl(privdata->mmio + AMD_P2C_MSG2);
>> +		if (val != 0) {
>> +			writel(0, privdata->mmio + AMD_P2C_MSG_INTEN);
>> +			privdata->eventval.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;
>> +	size_t buf_size;
>> +	ssize_t ret, off;
>> +	union {
>> +		u64 v64;
>> +		u32 v32;
>> +		u16 v16;
>> +	} u;
>> +
>> +	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");
>> +	u.v32 = readl(privdata->mmio + AMD_C2P_MSG0);
>> +	off += scnprintf(buf + off, buf_size - off,
>> +			"AMD_C2P_MSG0 -\t\t\t%#06x\n", u.v32);
>> +
>> +	u.v32 = readl(privdata->mmio + AMD_C2P_MSG1);
>> +	off += scnprintf(buf + off, buf_size - off,
>> +			"AMD_C2P_MSG1 -\t\t\t%#06x\n", u.v32);
>> +
>> +	u.v32 = readl(privdata->mmio + AMD_C2P_MSG2);
>> +	off += scnprintf(buf + off, buf_size - off,
>> +			"AMD_C2P_MSG2 -\t\t\t%#06x\n", u.v32);
>> +
>> +	u.v32 = readl(privdata->mmio + AMD_C2P_MSG3);
>> +	off += scnprintf(buf + off, buf_size - off,
>> +			"AMD_C2P_MSG3 -\t\t\t%#06x\n", u.v32);
>> +
>> +	u.v32 = readl(privdata->mmio + AMD_C2P_MSG4);
>> +	off += scnprintf(buf + off, buf_size - off,
>> +			"AMD_C2P_MSG4 -\t\t\t%#06x\n", u.v32);
>> +
>> +	u.v32 = readl(privdata->mmio + AMD_C2P_MSG5);
>> +	off += scnprintf(buf + off, buf_size - off,
>> +			"AMD_C2P_MSG5 -\t\t\t%#06x\n", u.v32);
>> +
>> +	u.v32 = readl(privdata->mmio + AMD_C2P_MSG6);
>> +	off += scnprintf(buf + off, buf_size - off,
>> +			"AMD_C2P_MSG6 -\t\t\t%#06x\n", u.v32);
>> +
>> +	u.v32 = readl(privdata->mmio + AMD_C2P_MSG7);
>> +	off += scnprintf(buf + off, buf_size - off,
>> +			"AMD_C2P_MSG7 -\t\t\t%#06x\n", u.v32);
>> +
>> +	u.v32 = readl(privdata->mmio + AMD_C2P_MSG8);
>> +	off += scnprintf(buf + off, buf_size - off,
>> +			"AMD_C2P_MSG8 -\t\t\t%#06x\n", u.v32);
>> +
>> +	u.v32 = readl(privdata->mmio + AMD_C2P_MSG9);
>> +	off += scnprintf(buf + off, buf_size - off,
>> +			"AMD_C2P_MSG9 -\t\t\t%#06x\n", u.v32);
>> +
>> +	off += scnprintf(buf + off, buf_size - off,
>> +			"\n\tMP2 P2C Message Register Dump:\n\n");
>> +
>> +	u.v32 = readl(privdata->mmio + AMD_P2C_MSG1);
>> +	off += scnprintf(buf + off, buf_size - off,
>> +			"AMD_P2C_MSG1 -\t\t\t%#06x\n", u.v32);
>> +
>> +	u.v32 = readl(privdata->mmio + AMD_P2C_MSG2);
>> +	off += scnprintf(buf + off, buf_size - off,
>> +			"AMD_P2C_MSG2 -\t\t\t%#06x\n", u.v32);
>> +
>> +	u.v32 = readl(privdata->mmio + AMD_P2C_MSG_INTEN);
>> +	off += scnprintf(buf + off, buf_size - off,
>> +			"AMD_P2C_MSG_INTEN -\t\t%#06x\n", u.v32);
>> +
>> +	u.v32 = readl(privdata->mmio + AMD_P2C_MSG_INTSTS);
>> +	off += scnprintf(buf + off, buf_size - off,
>> +			"AMD_P2C_MSG_INTSTS -\t\t%#06x\n", u.v32);
>> +
>> +	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);
>> +	dev_dbg(ndev_dev(privdata), "Base addr:%llx size:%llx\n", base, size);
>> +
>> +	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 000000000000..a84389122885
>> --- /dev/null
>> +++ b/drivers/i2c/busses/i2c-amd-pci-mp2.h
>> @@ -0,0 +1,251 @@
>> +/* SPDX-License-Identifier: GPL-2.0
>> + *
>> + * This file is provided under a dual BSD/GPLv2 license.  When using or
>> + *   redistributing this file, you may do so under either license.
>> + *
>> + *   GPL LICENSE SUMMARY
>> + *
>> + *   Copyright (C) 2018 Advanced Micro Devices, Inc. All Rights Reserved.
>> + *
>> + *   This program is free software; you can redistribute it and/or modify
>> + *   it under the terms of version 2 of the GNU General Public License as
>> + *   published by the Free Software Foundation.
>> + *
>> + *   BSD LICENSE
>> + *
>> + *   Copyright (C) 2018 Advanced Micro Devices, Inc. All Rights Reserved.
>> + *
>> + *   Redistribution and use in source and binary forms, with or without
>> + *   modification, are permitted provided that the following conditions
>> + *   are met:
>> + *
>> + *     * Redistributions of source code must retain the above copyright
>> + *       notice, this list of conditions and the following disclaimer.
>> + *     * Redistributions in binary form must reproduce the above copy
>> + *       notice, this list of conditions and the following disclaimer in
>> + *       the documentation and/or other materials provided with the
>> + *       distribution.
>> + *     * Neither the name of AMD Corporation nor the names of its
>> + *       contributors may be used to endorse or promote products derived
>> + *       from this software without specific prior written permission.
>> + *
>> + *   THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
>> + *   "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
>> + *   LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS  
>> FOR
>> + *   A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
>> + *   OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT,  
>> INCIDENTAL,
>> + *   SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
>> + *   LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF  
>> USE,
>> + *   DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON  
>> ANY
>> + *   THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
>> + *   (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE  
>> USE
>> + *   OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
>> + *
>> + * AMD PCIe MP2 Communication Interface Driver
>> + * Author: Shyam Sundar S K <Shyam-sundar.S-k at amd.com>
>> + */
>> +
>> +#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
>> +};
>> +
>> +union i2c_event_base {
>> +	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 */
>> +	u32 *buf;
>> +};
>> +
>> +/* data structures for communication with I2c*/
>> +
>> +struct i2c_connect_config {
>> +	enum i2c_bus_index bus_id;
>> +	u64 i2c_speed;
>> +	u16 dev_addr;
>> +};
>> +
>> +struct i2c_write_config {
>> +	enum i2c_bus_index bus_id;
>> +	u64 i2c_speed;
>> +	u16 dev_addr;
>> +	u32 length;
>> +	phys_addr_t phy_addr;
>> +	u32 *buf;
>> +};
>> +
>> +struct i2c_read_config {
>> +	enum i2c_bus_index bus_id;
>> +	u64 i2c_speed;
>> +	u16 dev_addr;
>> +	u32 length;
>> +	phys_addr_t phy_addr;
>> +	u8 *buf;
>> +};
>> +
>> +// struct to send/receive data b/w pci and i2c drivers
>> +struct amd_i2c_pci_ops {
>> +	int (*read_complete)(union i2c_event_base event, void *dev_ctx);
>> +	int (*write_complete)(union i2c_event_base event, void *dev_ctx);
>> +	int (*connect_complete)(union i2c_event_base event, void *dev_ctx);
>> +};
>> +
>> +struct amd_i2c_common {
>> +	struct i2c_connect_config connect_cfg;
>> +	struct i2c_read_config read_cfg;
>> +	struct i2c_write_config write_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;
>> +	union i2c_event_base eventval;
>> +	enum i2c_cmd reqcmd;
>> +	struct i2c_connect_config connect_cfg;
>> +	struct i2c_read_config read_cfg;
>> +	struct i2c_write_config write_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_read_config read_cfg);
>> +int amd_mp2_write(struct pci_dev *pdev,
>> +		  struct i2c_write_config write_cfg);
>> +int amd_mp2_connect(struct pci_dev *pdev,
>> +		    struct i2c_connect_config connect_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 000000000000..5f195c98ca9e
>> --- /dev/null
>> +++ b/drivers/i2c/busses/i2c-amd-platdrv.c
>> @@ -0,0 +1,332 @@
>> +// SPDX-License-Identifier: GPL-2.0
>> +/*
>> + *
>> + * This file is provided under a dual BSD/GPLv2 license.  When using or
>> + *   redistributing this file, you may do so under either license.
>> + *
>> + *   GPL LICENSE SUMMARY
>> + *
>> + *   Copyright (C) 2018 Advanced Micro Devices, Inc. All Rights Reserved.
>> + *
>> + *   This program is free software; you can redistribute it and/or modify
>> + *   it under the terms of version 2 of the GNU General Public License as
>> + *   published by the Free Software Foundation.
>> + *
>> + *   BSD LICENSE
>> + *
>> + *   Copyright (C) 2018 Advanced Micro Devices, Inc. All Rights Reserved.
>> + *
>> + *   Redistribution and use in source and binary forms, with or without
>> + *   modification, are permitted provided that the following conditions
>> + *   are met:
>> + *
>> + *     * Redistributions of source code must retain the above copyright
>> + *       notice, this list of conditions and the following disclaimer.
>> + *     * Redistributions in binary form must reproduce the above copy
>> + *       notice, this list of conditions and the following disclaimer in
>> + *       the documentation and/or other materials provided with the
>> + *       distribution.
>> + *     * Neither the name of AMD Corporation nor the names of its
>> + *       contributors may be used to endorse or promote products derived
>> + *       from this software without specific prior written permission.
>> + *
>> + *   THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
>> + *   "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
>> + *   LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS  
>> FOR
>> + *   A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
>> + *   OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT,  
>> INCIDENTAL,
>> + *   SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
>> + *   LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF  
>> USE,
>> + *   DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON  
>> ANY
>> + *   THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
>> + *   (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE  
>> USE
>> + *   OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
>> + *
>> +
>> + * AMD I2C Platform Driver
>> + * Author: Nehal Bakulchandra Shah <Nehal-bakulchandra.shah at amd.com>
>> + */
>> +
>> +#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/acpi.h>
>> +#include <linux/delay.h>
>> +#include "i2c-amd-pci-mp2.h"
>> +#include <linux/dma-mapping.h>
>> +#define  DRIVER_NAME "AMD-I2C-PLATDRV"
>> +
>> +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(union i2c_event_base 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.r.status == i2c_readcomplete_event) {
>> +		if (event.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.r.length);
>> +
>> +			for (i = 0; i < ((event.r.length + 3) / 4); i++)
>> +				pr_devel("%s:%s readdata:%x\n",
>> +					 DRIVER_NAME, __func__, event.buf[i]);
>> +
>> +		} else {
>> +			memcpy(i2c_dev->msg_buf->buf,
>> +			       (unsigned char *)commond->read_cfg.buf,
>> +				event.r.length);
>> +			pr_devel("%s:%s virt:%llx phy_addr:%llx\n",
>> +				 DRIVER_NAME, __func__,
>> +				(u64)commond->read_cfg.buf,
>> +				(u64)commond->read_cfg.phy_addr);
>> +
>> +			for (i = 0; i < ((event.r.length + 3) / 4); i++)
>> +				pr_devel("%s:%s readdata:%x\n",
>> +					 DRIVER_NAME, __func__, ((unsigned int *)
>> +				commond->read_cfg.buf)[i]);
>> +		}
>> +
>> +		complete(&i2c_dev->msg_complete);
>> +	}
>> +
>> +	return 0;
>> +}
>> +
>> +static int i2c_amd_write_completion(union i2c_event_base event, void  
>> *dev_ctx)
>> +{
>> +	struct amd_i2c_dev *i2c_dev = (struct amd_i2c_dev *)dev_ctx;
>> +
>> +	if (event.r.status == i2c_writecomplete_event)
>> +		complete(&i2c_dev->msg_complete);
>> +
>> +	return 0;
>> +}
>> +
>> +static int i2c_amd_connect_completion(union i2c_event_base event, void  
>> *dev_ctx)
>> +{
>> +	struct amd_i2c_dev *i2c_dev = (struct amd_i2c_dev *)dev_ctx;
>> +
>> +	if (event.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->connect_cfg.bus_id = i2c_dev->bus_id;
>> +	i2c_common->connect_cfg.dev_addr = slaveaddr;
>> +	i2c_common->connect_cfg.i2c_speed = speed400k;
>> +
>> +	ret = amd_mp2_connect(i2c_common->pdev, i2c_common->connect_cfg);
>> +	if (ret)
>> +		return -1;
>> +
>> +	mdelay(100);
>> +
>> +	i2c_common->write_cfg.bus_id = i2c_dev->bus_id;
>> +	i2c_common->write_cfg.dev_addr = slaveaddr;
>> +	i2c_common->write_cfg.i2c_speed = speed400k;
>> +
>> +	i2c_common->read_cfg.bus_id = i2c_dev->bus_id;
>> +	i2c_common->read_cfg.dev_addr = slaveaddr;
>> +	i2c_common->read_cfg.i2c_speed = speed400k;
>> +
>> +	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 = 0;
>> +	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];
>> +		if (pmsg->flags & I2C_M_RD) {
>> +			if (pmsg->len <= 32) {
>> +				i2c_common->read_cfg.buf = dev->buf;
>> +				i2c_common->read_cfg.length = pmsg->len;
>> +				i2c_common->read_cfg.phy_addr =
>> +							virt_to_phys(dev->buf);
>> +			} else {
>> +				dma_buf = (u8 *)dma_alloc_coherent(&i2c_common->pdev->dev,
>> +					pmsg->len, &phys, GFP_KERNEL);
>> +
>> +				if (!dma_buf)
>> +					return -ENOMEM;
>> +
>> +				i2c_common->read_cfg.buf = dma_buf;
>> +				i2c_common->read_cfg.length = pmsg->len;
>> +				i2c_common->read_cfg.phy_addr = phys;
>> +			}
>> +			dev->msg_buf = pmsg;
>> +			amd_mp2_read(i2c_common->pdev,
>> +				     i2c_common->read_cfg);
>> +			timeout = wait_for_completion_timeout
>> +					(&dev->msg_complete, 50);
>> +			if (pmsg->len > 32 && dma_buf)
>> +				dma_free_coherent(&i2c_common->pdev->dev,
>> +						  pmsg->len, dma_buf, phys);
>> +
>> +		} else {
>> +			i2c_common->write_cfg.buf = (unsigned int *)pmsg->buf;
>> +			i2c_common->write_cfg.length = pmsg->len;
>> +			amd_mp2_write(i2c_common->pdev,
>> +				      i2c_common->write_cfg);
>> +
>> +			timeout = wait_for_completion_timeout
>> +						(&dev->msg_complete, 50);
>> +		}
>> +	}
>> +	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;
>> +	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;
>> +	}
>> +	i2c_dev->buf = kzalloc(32, GFP_KERNEL);
>> +
>> +	if (!i2c_dev->buf)
>> +		return -ENOMEM;
>> +
>> +	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 at amd.com>");
>> +MODULE_DESCRIPTION("AMD I2C Platform Driver");
>> +MODULE_LICENSE("Dual BSD/GPL");
>> +




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