at 18:54, Shah, Nehal-bakulchandra <nehal-bakulchandra.s...@amd.com> wrote:

From: Nehal-bakulchandra Shah <nehal-bakulchandra.s...@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....@amd.com>
Reviewed-by: Sandeep Singh <sandeep.si...@amd.com>
Signed-off-by: Nehal-bakulchandra Shah <nehal-bakulchandra.s...@amd.com>

The I2C touchpad on Latitude 5495 works with this patch.

Tested-by: Kai-Heng Feng <kai.heng.f...@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....@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....@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....@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.s...@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.s...@amd.com>");
+MODULE_DESCRIPTION("AMD I2C Platform Driver");
+MODULE_LICENSE("Dual BSD/GPL");
--
2.7.4


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