[PATCH] i2c: move acpi code back into the core

[PATCH] i2c: move acpi code back into the core

[Wolfram Sang]

Commit 5d98e61d337c ("I2C/ACPI: Add i2c ACPI operation region support") renamed
the i2c-core module. This may cause regressions for distributions, so put the
ACPI code back into the core. No code was changed.

Reported-by: Jean Delvare <jdelvare@suse.de>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
Cc: Mika Westerberg <mika.westerberg@linux.intel.com>
Cc: Lan Tianyu <tianyu.lan@intel.com>
Cc: Jean Delvare <jdelvare@suse.de>
---

Lan Tianyi, this is a patch I expected to get from you, fully tested. Since we
are approaching the final release soon, I did it now. Please do test this
patch. All I can do is build test (it works for me, build robots are still
running). If nobody tests this, I have to revert the ACPI changes of this
cycle.

Jean, can you have a look, too?

We can think of something better for the next release, but for now, this should be it.

 MAINTAINERS            |   1 -
 drivers/i2c/Makefile   |   5 +-
 drivers/i2c/i2c-acpi.c | 364 -------------------------------------------------
 drivers/i2c/i2c-core.c | 345 ++++++++++++++++++++++++++++++++++++++++++++++
 4 files changed, 346 insertions(+), 369 deletions(-)
 delete mode 100644 drivers/i2c/i2c-acpi.c

diff --git a/MAINTAINERS b/MAINTAINERS
index 809ecd680d88..e3682d0dea1e 100644
--- a/MAINTAINERS
+++ b/MAINTAINERS
@@ -4477,7 +4477,6 @@ M:	Mika Westerberg <mika.westerberg@linux.intel.com>
 L:	linux-i2c@vger.kernel.org
 L:	linux-acpi@vger.kernel.org
 S:	Maintained
-F:	drivers/i2c/i2c-acpi.c
 
 I2C-TAOS-EVM DRIVER
 M:	Jean Delvare <jdelvare@suse.de>
diff --git a/drivers/i2c/Makefile b/drivers/i2c/Makefile
index e0228b228256..1722f50f2473 100644
--- a/drivers/i2c/Makefile
+++ b/drivers/i2c/Makefile
@@ -2,11 +2,8 @@
 # Makefile for the i2c core.
 #
 
-i2ccore-y := i2c-core.o
-i2ccore-$(CONFIG_ACPI)	 	+= i2c-acpi.o
-
 obj-$(CONFIG_I2C_BOARDINFO)	+= i2c-boardinfo.o
-obj-$(CONFIG_I2C)		+= i2ccore.o
+obj-$(CONFIG_I2C)		+= i2c-core.o
 obj-$(CONFIG_I2C_SMBUS)		+= i2c-smbus.o
 obj-$(CONFIG_I2C_CHARDEV)	+= i2c-dev.o
 obj-$(CONFIG_I2C_MUX)		+= i2c-mux.o
diff --git a/drivers/i2c/i2c-acpi.c b/drivers/i2c/i2c-acpi.c
deleted file mode 100644
index 0dbc18c15c43..000000000000
--- a/drivers/i2c/i2c-acpi.c
+++ /dev/null
@@ -1,364 +0,0 @@
-/*
- * I2C ACPI code
- *
- * Copyright (C) 2014 Intel Corp
- *
- * Author: Lan Tianyu <tianyu.lan@intel.com>
- *
- * This program is free software; you can redistribute it and/or modify
- * it under the terms of the GNU General Public License version 2 as
- * published by the Free Software Foundation.
- *
- * This program is distributed in the hope that it will be useful, but
- * WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY
- * or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
- * for more details.
- */
-#define pr_fmt(fmt) "I2C/ACPI : " fmt
-
-#include <linux/kernel.h>
-#include <linux/errno.h>
-#include <linux/err.h>
-#include <linux/i2c.h>
-#include <linux/acpi.h>
-
-struct acpi_i2c_handler_data {
-	struct acpi_connection_info info;
-	struct i2c_adapter *adapter;
-};
-
-struct gsb_buffer {
-	u8	status;
-	u8	len;
-	union {
-		u16	wdata;
-		u8	bdata;
-		u8	data[0];
-	};
-} __packed;
-
-static int acpi_i2c_add_resource(struct acpi_resource *ares, void *data)
-{
-	struct i2c_board_info *info = data;
-
-	if (ares->type == ACPI_RESOURCE_TYPE_SERIAL_BUS) {
-		struct acpi_resource_i2c_serialbus *sb;
-
-		sb = &ares->data.i2c_serial_bus;
-		if (sb->type == ACPI_RESOURCE_SERIAL_TYPE_I2C) {
-			info->addr = sb->slave_address;
-			if (sb->access_mode == ACPI_I2C_10BIT_MODE)
-				info->flags |= I2C_CLIENT_TEN;
-		}
-	} else if (info->irq < 0) {
-		struct resource r;
-
-		if (acpi_dev_resource_interrupt(ares, 0, &r))
-			info->irq = r.start;
-	}
-
-	/* Tell the ACPI core to skip this resource */
-	return 1;
-}
-
-static acpi_status acpi_i2c_add_device(acpi_handle handle, u32 level,
-				       void *data, void **return_value)
-{
-	struct i2c_adapter *adapter = data;
-	struct list_head resource_list;
-	struct i2c_board_info info;
-	struct acpi_device *adev;
-	int ret;
-
-	if (acpi_bus_get_device(handle, &adev))
-		return AE_OK;
-	if (acpi_bus_get_status(adev) || !adev->status.present)
-		return AE_OK;
-
-	memset(&info, 0, sizeof(info));
-	info.acpi_node.companion = adev;
-	info.irq = -1;
-
-	INIT_LIST_HEAD(&resource_list);
-	ret = acpi_dev_get_resources(adev, &resource_list,
-				     acpi_i2c_add_resource, &info);
-	acpi_dev_free_resource_list(&resource_list);
-
-	if (ret < 0 || !info.addr)
-		return AE_OK;
-
-	adev->power.flags.ignore_parent = true;
-	strlcpy(info.type, dev_name(&adev->dev), sizeof(info.type));
-	if (!i2c_new_device(adapter, &info)) {
-		adev->power.flags.ignore_parent = false;
-		dev_err(&adapter->dev,
-			"failed to add I2C device %s from ACPI\n",
-			dev_name(&adev->dev));
-	}
-
-	return AE_OK;
-}
-
-/**
- * acpi_i2c_register_devices - enumerate I2C slave devices behind adapter
- * @adap: pointer to adapter
- *
- * Enumerate all I2C slave devices behind this adapter by walking the ACPI
- * namespace. When a device is found it will be added to the Linux device
- * model and bound to the corresponding ACPI handle.
- */
-void acpi_i2c_register_devices(struct i2c_adapter *adap)
-{
-	acpi_handle handle;
-	acpi_status status;
-
-	if (!adap->dev.parent)
-		return;
-
-	handle = ACPI_HANDLE(adap->dev.parent);
-	if (!handle)
-		return;
-
-	status = acpi_walk_namespace(ACPI_TYPE_DEVICE, handle, 1,
-				     acpi_i2c_add_device, NULL,
-				     adap, NULL);
-	if (ACPI_FAILURE(status))
-		dev_warn(&adap->dev, "failed to enumerate I2C slaves\n");
-}
-
-#ifdef CONFIG_ACPI_I2C_OPREGION
-static int acpi_gsb_i2c_read_bytes(struct i2c_client *client,
-		u8 cmd, u8 *data, u8 data_len)
-{
-
-	struct i2c_msg msgs[2];
-	int ret;
-	u8 *buffer;
-
-	buffer = kzalloc(data_len, GFP_KERNEL);
-	if (!buffer)
-		return AE_NO_MEMORY;
-
-	msgs[0].addr = client->addr;
-	msgs[0].flags = client->flags;
-	msgs[0].len = 1;
-	msgs[0].buf = &cmd;
-
-	msgs[1].addr = client->addr;
-	msgs[1].flags = client->flags | I2C_M_RD;
-	msgs[1].len = data_len;
-	msgs[1].buf = buffer;
-
-	ret = i2c_transfer(client->adapter, msgs, ARRAY_SIZE(msgs));
-	if (ret < 0)
-		dev_err(&client->adapter->dev, "i2c read failed\n");
-	else
-		memcpy(data, buffer, data_len);
-
-	kfree(buffer);
-	return ret;
-}
-
-static int acpi_gsb_i2c_write_bytes(struct i2c_client *client,
-		u8 cmd, u8 *data, u8 data_len)
-{
-
-	struct i2c_msg msgs[1];
-	u8 *buffer;
-	int ret = AE_OK;
-
-	buffer = kzalloc(data_len + 1, GFP_KERNEL);
-	if (!buffer)
-		return AE_NO_MEMORY;
-
-	buffer[0] = cmd;
-	memcpy(buffer + 1, data, data_len);
-
-	msgs[0].addr = client->addr;
-	msgs[0].flags = client->flags;
-	msgs[0].len = data_len + 1;
-	msgs[0].buf = buffer;
-
-	ret = i2c_transfer(client->adapter, msgs, ARRAY_SIZE(msgs));
-	if (ret < 0)
-		dev_err(&client->adapter->dev, "i2c write failed\n");
-
-	kfree(buffer);
-	return ret;
-}
-
-static acpi_status
-acpi_i2c_space_handler(u32 function, acpi_physical_address command,
-			u32 bits, u64 *value64,
-			void *handler_context, void *region_context)
-{
-	struct gsb_buffer *gsb = (struct gsb_buffer *)value64;
-	struct acpi_i2c_handler_data *data = handler_context;
-	struct acpi_connection_info *info = &data->info;
-	struct acpi_resource_i2c_serialbus *sb;
-	struct i2c_adapter *adapter = data->adapter;
-	struct i2c_client client;
-	struct acpi_resource *ares;
-	u32 accessor_type = function >> 16;
-	u8 action = function & ACPI_IO_MASK;
-	acpi_status ret = AE_OK;
-	int status;
-
-	ret = acpi_buffer_to_resource(info->connection, info->length, &ares);
-	if (ACPI_FAILURE(ret))
-		return ret;
-
-	if (!value64 || ares->type != ACPI_RESOURCE_TYPE_SERIAL_BUS) {
-		ret = AE_BAD_PARAMETER;
-		goto err;
-	}
-
-	sb = &ares->data.i2c_serial_bus;
-	if (sb->type != ACPI_RESOURCE_SERIAL_TYPE_I2C) {
-		ret = AE_BAD_PARAMETER;
-		goto err;
-	}
-
-	memset(&client, 0, sizeof(client));
-	client.adapter = adapter;
-	client.addr = sb->slave_address;
-	client.flags = 0;
-
-	if (sb->access_mode == ACPI_I2C_10BIT_MODE)
-		client.flags |= I2C_CLIENT_TEN;
-
-	switch (accessor_type) {
-	case ACPI_GSB_ACCESS_ATTRIB_SEND_RCV:
-		if (action == ACPI_READ) {
-			status = i2c_smbus_read_byte(&client);
-			if (status >= 0) {
-				gsb->bdata = status;
-				status = 0;
-			}
-		} else {
-			status = i2c_smbus_write_byte(&client, gsb->bdata);
-		}
-		break;
-
-	case ACPI_GSB_ACCESS_ATTRIB_BYTE:
-		if (action == ACPI_READ) {
-			status = i2c_smbus_read_byte_data(&client, command);
-			if (status >= 0) {
-				gsb->bdata = status;
-				status = 0;
-			}
-		} else {
-			status = i2c_smbus_write_byte_data(&client, command,
-					gsb->bdata);
-		}
-		break;
-
-	case ACPI_GSB_ACCESS_ATTRIB_WORD:
-		if (action == ACPI_READ) {
-			status = i2c_smbus_read_word_data(&client, command);
-			if (status >= 0) {
-				gsb->wdata = status;
-				status = 0;
-			}
-		} else {
-			status = i2c_smbus_write_word_data(&client, command,
-					gsb->wdata);
-		}
-		break;
-
-	case ACPI_GSB_ACCESS_ATTRIB_BLOCK:
-		if (action == ACPI_READ) {
-			status = i2c_smbus_read_block_data(&client, command,
-					gsb->data);
-			if (status >= 0) {
-				gsb->len = status;
-				status = 0;
-			}
-		} else {
-			status = i2c_smbus_write_block_data(&client, command,
-					gsb->len, gsb->data);
-		}
-		break;
-
-	case ACPI_GSB_ACCESS_ATTRIB_MULTIBYTE:
-		if (action == ACPI_READ) {
-			status = acpi_gsb_i2c_read_bytes(&client, command,
-					gsb->data, info->access_length);
-			if (status > 0)
-				status = 0;
-		} else {
-			status = acpi_gsb_i2c_write_bytes(&client, command,
-					gsb->data, info->access_length);
-		}
-		break;
-
-	default:
-		pr_info("protocol(0x%02x) is not supported.\n", accessor_type);
-		ret = AE_BAD_PARAMETER;
-		goto err;
-	}
-
-	gsb->status = status;
-
- err:
-	ACPI_FREE(ares);
-	return ret;
-}
-
-
-int acpi_i2c_install_space_handler(struct i2c_adapter *adapter)
-{
-	acpi_handle handle = ACPI_HANDLE(adapter->dev.parent);
-	struct acpi_i2c_handler_data *data;
-	acpi_status status;
-
-	if (!handle)
-		return -ENODEV;
-
-	data = kzalloc(sizeof(struct acpi_i2c_handler_data),
-			    GFP_KERNEL);
-	if (!data)
-		return -ENOMEM;
-
-	data->adapter = adapter;
-	status = acpi_bus_attach_private_data(handle, (void *)data);
-	if (ACPI_FAILURE(status)) {
-		kfree(data);
-		return -ENOMEM;
-	}
-
-	status = acpi_install_address_space_handler(handle,
-				ACPI_ADR_SPACE_GSBUS,
-				&acpi_i2c_space_handler,
-				NULL,
-				data);
-	if (ACPI_FAILURE(status)) {
-		dev_err(&adapter->dev, "Error installing i2c space handler\n");
-		acpi_bus_detach_private_data(handle);
-		kfree(data);
-		return -ENOMEM;
-	}
-
-	return 0;
-}
-
-void acpi_i2c_remove_space_handler(struct i2c_adapter *adapter)
-{
-	acpi_handle handle = ACPI_HANDLE(adapter->dev.parent);
-	struct acpi_i2c_handler_data *data;
-	acpi_status status;
-
-	if (!handle)
-		return;
-
-	acpi_remove_address_space_handler(handle,
-				ACPI_ADR_SPACE_GSBUS,
-				&acpi_i2c_space_handler);
-
-	status = acpi_bus_get_private_data(handle, (void **)&data);
-	if (ACPI_SUCCESS(status))
-		kfree(data);
-
-	acpi_bus_detach_private_data(handle);
-}
-#endif
diff --git a/drivers/i2c/i2c-core.c b/drivers/i2c/i2c-core.c
index 632057a44615..3fbd5d5c38bf 100644
--- a/drivers/i2c/i2c-core.c
+++ b/drivers/i2c/i2c-core.c
@@ -27,6 +27,8 @@
    OF support is copyright (c) 2008 Jochen Friedrich <jochen@scram.de>
    (based on a previous patch from Jon Smirl <jonsmirl@gmail.com>) and
    (c) 2013  Wolfram Sang <wsa@the-dreams.de>
+   I2C ACPI code Copyright (C) 2014 Intel Corp
+   Author: Lan Tianyu <tianyu.lan@intel.com>
  */
 
 #include <linux/module.h>
@@ -78,6 +80,349 @@ void i2c_transfer_trace_unreg(void)
 	static_key_slow_dec(&i2c_trace_msg);
 }
 
+#if defined(CONFIG_ACPI)
+struct acpi_i2c_handler_data {
+	struct acpi_connection_info info;
+	struct i2c_adapter *adapter;
+};
+
+struct gsb_buffer {
+	u8	status;
+	u8	len;
+	union {
+		u16	wdata;
+		u8	bdata;
+		u8	data[0];
+	};
+} __packed;
+
+static int acpi_i2c_add_resource(struct acpi_resource *ares, void *data)
+{
+	struct i2c_board_info *info = data;
+
+	if (ares->type == ACPI_RESOURCE_TYPE_SERIAL_BUS) {
+		struct acpi_resource_i2c_serialbus *sb;
+
+		sb = &ares->data.i2c_serial_bus;
+		if (sb->type == ACPI_RESOURCE_SERIAL_TYPE_I2C) {
+			info->addr = sb->slave_address;
+			if (sb->access_mode == ACPI_I2C_10BIT_MODE)
+				info->flags |= I2C_CLIENT_TEN;
+		}
+	} else if (info->irq < 0) {
+		struct resource r;
+
+		if (acpi_dev_resource_interrupt(ares, 0, &r))
+			info->irq = r.start;
+	}
+
+	/* Tell the ACPI core to skip this resource */
+	return 1;
+}
+
+static acpi_status acpi_i2c_add_device(acpi_handle handle, u32 level,
+				       void *data, void **return_value)
+{
+	struct i2c_adapter *adapter = data;
+	struct list_head resource_list;
+	struct i2c_board_info info;
+	struct acpi_device *adev;
+	int ret;
+
+	if (acpi_bus_get_device(handle, &adev))
+		return AE_OK;
+	if (acpi_bus_get_status(adev) || !adev->status.present)
+		return AE_OK;
+
+	memset(&info, 0, sizeof(info));
+	info.acpi_node.companion = adev;
+	info.irq = -1;
+
+	INIT_LIST_HEAD(&resource_list);
+	ret = acpi_dev_get_resources(adev, &resource_list,
+				     acpi_i2c_add_resource, &info);
+	acpi_dev_free_resource_list(&resource_list);
+
+	if (ret < 0 || !info.addr)
+		return AE_OK;
+
+	adev->power.flags.ignore_parent = true;
+	strlcpy(info.type, dev_name(&adev->dev), sizeof(info.type));
+	if (!i2c_new_device(adapter, &info)) {
+		adev->power.flags.ignore_parent = false;
+		dev_err(&adapter->dev,
+			"failed to add I2C device %s from ACPI\n",
+			dev_name(&adev->dev));
+	}
+
+	return AE_OK;
+}
+
+/**
+ * acpi_i2c_register_devices - enumerate I2C slave devices behind adapter
+ * @adap: pointer to adapter
+ *
+ * Enumerate all I2C slave devices behind this adapter by walking the ACPI
+ * namespace. When a device is found it will be added to the Linux device
+ * model and bound to the corresponding ACPI handle.
+ */
+void acpi_i2c_register_devices(struct i2c_adapter *adap)
+{
+	acpi_handle handle;
+	acpi_status status;
+
+	if (!adap->dev.parent)
+		return;
+
+	handle = ACPI_HANDLE(adap->dev.parent);
+	if (!handle)
+		return;
+
+	status = acpi_walk_namespace(ACPI_TYPE_DEVICE, handle, 1,
+				     acpi_i2c_add_device, NULL,
+				     adap, NULL);
+	if (ACPI_FAILURE(status))
+		dev_warn(&adap->dev, "failed to enumerate I2C slaves\n");
+}
+
+#ifdef CONFIG_ACPI_I2C_OPREGION
+static int acpi_gsb_i2c_read_bytes(struct i2c_client *client,
+		u8 cmd, u8 *data, u8 data_len)
+{
+
+	struct i2c_msg msgs[2];
+	int ret;
+	u8 *buffer;
+
+	buffer = kzalloc(data_len, GFP_KERNEL);
+	if (!buffer)
+		return AE_NO_MEMORY;
+
+	msgs[0].addr = client->addr;
+	msgs[0].flags = client->flags;
+	msgs[0].len = 1;
+	msgs[0].buf = &cmd;
+
+	msgs[1].addr = client->addr;
+	msgs[1].flags = client->flags | I2C_M_RD;
+	msgs[1].len = data_len;
+	msgs[1].buf = buffer;
+
+	ret = i2c_transfer(client->adapter, msgs, ARRAY_SIZE(msgs));
+	if (ret < 0)
+		dev_err(&client->adapter->dev, "i2c read failed\n");
+	else
+		memcpy(data, buffer, data_len);
+
+	kfree(buffer);
+	return ret;
+}
+
+static int acpi_gsb_i2c_write_bytes(struct i2c_client *client,
+		u8 cmd, u8 *data, u8 data_len)
+{
+
+	struct i2c_msg msgs[1];
+	u8 *buffer;
+	int ret = AE_OK;
+
+	buffer = kzalloc(data_len + 1, GFP_KERNEL);
+	if (!buffer)
+		return AE_NO_MEMORY;
+
+	buffer[0] = cmd;
+	memcpy(buffer + 1, data, data_len);
+
+	msgs[0].addr = client->addr;
+	msgs[0].flags = client->flags;
+	msgs[0].len = data_len + 1;
+	msgs[0].buf = buffer;
+
+	ret = i2c_transfer(client->adapter, msgs, ARRAY_SIZE(msgs));
+	if (ret < 0)
+		dev_err(&client->adapter->dev, "i2c write failed\n");
+
+	kfree(buffer);
+	return ret;
+}
+
+static acpi_status
+acpi_i2c_space_handler(u32 function, acpi_physical_address command,
+			u32 bits, u64 *value64,
+			void *handler_context, void *region_context)
+{
+	struct gsb_buffer *gsb = (struct gsb_buffer *)value64;
+	struct acpi_i2c_handler_data *data = handler_context;
+	struct acpi_connection_info *info = &data->info;
+	struct acpi_resource_i2c_serialbus *sb;
+	struct i2c_adapter *adapter = data->adapter;
+	struct i2c_client client;
+	struct acpi_resource *ares;
+	u32 accessor_type = function >> 16;
+	u8 action = function & ACPI_IO_MASK;
+	acpi_status ret = AE_OK;
+	int status;
+
+	ret = acpi_buffer_to_resource(info->connection, info->length, &ares);
+	if (ACPI_FAILURE(ret))
+		return ret;
+
+	if (!value64 || ares->type != ACPI_RESOURCE_TYPE_SERIAL_BUS) {
+		ret = AE_BAD_PARAMETER;
+		goto err;
+	}
+
+	sb = &ares->data.i2c_serial_bus;
+	if (sb->type != ACPI_RESOURCE_SERIAL_TYPE_I2C) {
+		ret = AE_BAD_PARAMETER;
+		goto err;
+	}
+
+	memset(&client, 0, sizeof(client));
+	client.adapter = adapter;
+	client.addr = sb->slave_address;
+	client.flags = 0;
+
+	if (sb->access_mode == ACPI_I2C_10BIT_MODE)
+		client.flags |= I2C_CLIENT_TEN;
+
+	switch (accessor_type) {
+	case ACPI_GSB_ACCESS_ATTRIB_SEND_RCV:
+		if (action == ACPI_READ) {
+			status = i2c_smbus_read_byte(&client);
+			if (status >= 0) {
+				gsb->bdata = status;
+				status = 0;
+			}
+		} else {
+			status = i2c_smbus_write_byte(&client, gsb->bdata);
+		}
+		break;
+
+	case ACPI_GSB_ACCESS_ATTRIB_BYTE:
+		if (action == ACPI_READ) {
+			status = i2c_smbus_read_byte_data(&client, command);
+			if (status >= 0) {
+				gsb->bdata = status;
+				status = 0;
+			}
+		} else {
+			status = i2c_smbus_write_byte_data(&client, command,
+					gsb->bdata);
+		}
+		break;
+
+	case ACPI_GSB_ACCESS_ATTRIB_WORD:
+		if (action == ACPI_READ) {
+			status = i2c_smbus_read_word_data(&client, command);
+			if (status >= 0) {
+				gsb->wdata = status;
+				status = 0;
+			}
+		} else {
+			status = i2c_smbus_write_word_data(&client, command,
+					gsb->wdata);
+		}
+		break;
+
+	case ACPI_GSB_ACCESS_ATTRIB_BLOCK:
+		if (action == ACPI_READ) {
+			status = i2c_smbus_read_block_data(&client, command,
+					gsb->data);
+			if (status >= 0) {
+				gsb->len = status;
+				status = 0;
+			}
+		} else {
+			status = i2c_smbus_write_block_data(&client, command,
+					gsb->len, gsb->data);
+		}
+		break;
+
+	case ACPI_GSB_ACCESS_ATTRIB_MULTIBYTE:
+		if (action == ACPI_READ) {
+			status = acpi_gsb_i2c_read_bytes(&client, command,
+					gsb->data, info->access_length);
+			if (status > 0)
+				status = 0;
+		} else {
+			status = acpi_gsb_i2c_write_bytes(&client, command,
+					gsb->data, info->access_length);
+		}
+		break;
+
+	default:
+		pr_info("protocol(0x%02x) is not supported.\n", accessor_type);
+		ret = AE_BAD_PARAMETER;
+		goto err;
+	}
+
+	gsb->status = status;
+
+ err:
+	ACPI_FREE(ares);
+	return ret;
+}
+
+
+int acpi_i2c_install_space_handler(struct i2c_adapter *adapter)
+{
+	acpi_handle handle = ACPI_HANDLE(adapter->dev.parent);
+	struct acpi_i2c_handler_data *data;
+	acpi_status status;
+
+	if (!handle)
+		return -ENODEV;
+
+	data = kzalloc(sizeof(struct acpi_i2c_handler_data),
+			    GFP_KERNEL);
+	if (!data)
+		return -ENOMEM;
+
+	data->adapter = adapter;
+	status = acpi_bus_attach_private_data(handle, (void *)data);
+	if (ACPI_FAILURE(status)) {
+		kfree(data);
+		return -ENOMEM;
+	}
+
+	status = acpi_install_address_space_handler(handle,
+				ACPI_ADR_SPACE_GSBUS,
+				&acpi_i2c_space_handler,
+				NULL,
+				data);
+	if (ACPI_FAILURE(status)) {
+		dev_err(&adapter->dev, "Error installing i2c space handler\n");
+		acpi_bus_detach_private_data(handle);
+		kfree(data);
+		return -ENOMEM;
+	}
+
+	return 0;
+}
+
+void acpi_i2c_remove_space_handler(struct i2c_adapter *adapter)
+{
+	acpi_handle handle = ACPI_HANDLE(adapter->dev.parent);
+	struct acpi_i2c_handler_data *data;
+	acpi_status status;
+
+	if (!handle)
+		return;
+
+	acpi_remove_address_space_handler(handle,
+				ACPI_ADR_SPACE_GSBUS,
+				&acpi_i2c_space_handler);
+
+	status = acpi_bus_get_private_data(handle, (void **)&data);
+	if (ACPI_SUCCESS(status))
+		kfree(data);
+
+	acpi_bus_detach_private_data(handle);
+}
+#endif
+#endif /* CONFIG_ACPI */
+
 /* ------------------------------------------------------------------------- */
 
 static const struct i2c_device_id *i2c_match_id(const struct i2c_device_id *id,
-- 
2.0.0

Re: [PATCH] i2c: move acpi code back into the core

[Lan Tianyu]

On 2014年09月23日 05:06, Wolfram Sang wrote:
> Commit 5d98e61d337c ("I2C/ACPI: Add i2c ACPI operation region support") renamed
> the i2c-core module. This may cause regressions for distributions, so put the
> ACPI code back into the core. No code was changed.
> 
> Reported-by: Jean Delvare <jdelvare-l3A5Bk7waGM@public.gmane.org>
> Signed-off-by: Wolfram Sang <wsa-z923LK4zBo2bacvFa/9K2g@public.gmane.org>
> Cc: Mika Westerberg <mika.westerberg-VuQAYsv1563Yd54FQh9/CA@public.gmane.org>
> Cc: Lan Tianyu <tianyu.lan-ral2JQCrhuEAvxtiuMwx3w@public.gmane.org>
> Cc: Jean Delvare <jdelvare-l3A5Bk7waGM@public.gmane.org>
> ---
> 
> Lan Tianyi, this is a patch I expected to get from you, fully tested. Since we
> are approaching the final release soon, I did it now. Please do test this
> patch. All I can do is build test (it works for me, build robots are still
> running). If nobody tests this, I have to revert the ACPI changes of this
> cycle.

Hi Wolfram:

Sorry for later response due to sickness. I can't write this patch in
time. Sorry again. I will test it soon.

> 
> Jean, can you have a look, too?
> 
> We can think of something better for the next release, but for now, this should be it.
> 
>  MAINTAINERS            |   1 -
>  drivers/i2c/Makefile   |   5 +-
>  drivers/i2c/i2c-acpi.c | 364 -------------------------------------------------
>  drivers/i2c/i2c-core.c | 345 ++++++++++++++++++++++++++++++++++++++++++++++
>  4 files changed, 346 insertions(+), 369 deletions(-)
>  delete mode 100644 drivers/i2c/i2c-acpi.c
> 
> diff --git a/MAINTAINERS b/MAINTAINERS
> index 809ecd680d88..e3682d0dea1e 100644
> --- a/MAINTAINERS
> +++ b/MAINTAINERS
> @@ -4477,7 +4477,6 @@ M:	Mika Westerberg <mika.westerberg-VuQAYsv1560/9W2qTSuDoA@public.gmane.org.com>
>  L:	linux-i2c-u79uwXL29TY76Z2rM5mHXA@public.gmane.org
>  L:	linux-acpi-u79uwXL29TY76Z2rM5mHXA@public.gmane.org
>  S:	Maintained
> -F:	drivers/i2c/i2c-acpi.c
>  
>  I2C-TAOS-EVM DRIVER
>  M:	Jean Delvare <jdelvare-l3A5Bk7waGM@public.gmane.org>
> diff --git a/drivers/i2c/Makefile b/drivers/i2c/Makefile
> index e0228b228256..1722f50f2473 100644
> --- a/drivers/i2c/Makefile
> +++ b/drivers/i2c/Makefile
> @@ -2,11 +2,8 @@
>  # Makefile for the i2c core.
>  #
>  
> -i2ccore-y := i2c-core.o
> -i2ccore-$(CONFIG_ACPI)	 	+= i2c-acpi.o
> -
>  obj-$(CONFIG_I2C_BOARDINFO)	+= i2c-boardinfo.o
> -obj-$(CONFIG_I2C)		+= i2ccore.o
> +obj-$(CONFIG_I2C)		+= i2c-core.o
>  obj-$(CONFIG_I2C_SMBUS)		+= i2c-smbus.o
>  obj-$(CONFIG_I2C_CHARDEV)	+= i2c-dev.o
>  obj-$(CONFIG_I2C_MUX)		+= i2c-mux.o
> diff --git a/drivers/i2c/i2c-acpi.c b/drivers/i2c/i2c-acpi.c
> deleted file mode 100644
> index 0dbc18c15c43..000000000000
> --- a/drivers/i2c/i2c-acpi.c
> +++ /dev/null
> @@ -1,364 +0,0 @@
> -/*
> - * I2C ACPI code
> - *
> - * Copyright (C) 2014 Intel Corp
> - *
> - * Author: Lan Tianyu <tianyu.lan-ral2JQCrhuEAvxtiuMwx3w@public.gmane.org>
> - *
> - * This program is free software; you can redistribute it and/or modify
> - * it under the terms of the GNU General Public License version 2 as
> - * published by the Free Software Foundation.
> - *
> - * This program is distributed in the hope that it will be useful, but
> - * WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY
> - * or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
> - * for more details.
> - */
> -#define pr_fmt(fmt) "I2C/ACPI : " fmt
> -
> -#include <linux/kernel.h>
> -#include <linux/errno.h>
> -#include <linux/err.h>
> -#include <linux/i2c.h>
> -#include <linux/acpi.h>
> -
> -struct acpi_i2c_handler_data {
> -	struct acpi_connection_info info;
> -	struct i2c_adapter *adapter;
> -};
> -
> -struct gsb_buffer {
> -	u8	status;
> -	u8	len;
> -	union {
> -		u16	wdata;
> -		u8	bdata;
> -		u8	data[0];
> -	};
> -} __packed;
> -
> -static int acpi_i2c_add_resource(struct acpi_resource *ares, void *data)
> -{
> -	struct i2c_board_info *info = data;
> -
> -	if (ares->type == ACPI_RESOURCE_TYPE_SERIAL_BUS) {
> -		struct acpi_resource_i2c_serialbus *sb;
> -
> -		sb = &ares->data.i2c_serial_bus;
> -		if (sb->type == ACPI_RESOURCE_SERIAL_TYPE_I2C) {
> -			info->addr = sb->slave_address;
> -			if (sb->access_mode == ACPI_I2C_10BIT_MODE)
> -				info->flags |= I2C_CLIENT_TEN;
> -		}
> -	} else if (info->irq < 0) {
> -		struct resource r;
> -
> -		if (acpi_dev_resource_interrupt(ares, 0, &r))
> -			info->irq = r.start;
> -	}
> -
> -	/* Tell the ACPI core to skip this resource */
> -	return 1;
> -}
> -
> -static acpi_status acpi_i2c_add_device(acpi_handle handle, u32 level,
> -				       void *data, void **return_value)
> -{
> -	struct i2c_adapter *adapter = data;
> -	struct list_head resource_list;
> -	struct i2c_board_info info;
> -	struct acpi_device *adev;
> -	int ret;
> -
> -	if (acpi_bus_get_device(handle, &adev))
> -		return AE_OK;
> -	if (acpi_bus_get_status(adev) || !adev->status.present)
> -		return AE_OK;
> -
> -	memset(&info, 0, sizeof(info));
> -	info.acpi_node.companion = adev;
> -	info.irq = -1;
> -
> -	INIT_LIST_HEAD(&resource_list);
> -	ret = acpi_dev_get_resources(adev, &resource_list,
> -				     acpi_i2c_add_resource, &info);
> -	acpi_dev_free_resource_list(&resource_list);
> -
> -	if (ret < 0 || !info.addr)
> -		return AE_OK;
> -
> -	adev->power.flags.ignore_parent = true;
> -	strlcpy(info.type, dev_name(&adev->dev), sizeof(info.type));
> -	if (!i2c_new_device(adapter, &info)) {
> -		adev->power.flags.ignore_parent = false;
> -		dev_err(&adapter->dev,
> -			"failed to add I2C device %s from ACPI\n",
> -			dev_name(&adev->dev));
> -	}
> -
> -	return AE_OK;
> -}
> -
> -/**
> - * acpi_i2c_register_devices - enumerate I2C slave devices behind adapter
> - * @adap: pointer to adapter
> - *
> - * Enumerate all I2C slave devices behind this adapter by walking the ACPI
> - * namespace. When a device is found it will be added to the Linux device
> - * model and bound to the corresponding ACPI handle.
> - */
> -void acpi_i2c_register_devices(struct i2c_adapter *adap)
> -{
> -	acpi_handle handle;
> -	acpi_status status;
> -
> -	if (!adap->dev.parent)
> -		return;
> -
> -	handle = ACPI_HANDLE(adap->dev.parent);
> -	if (!handle)
> -		return;
> -
> -	status = acpi_walk_namespace(ACPI_TYPE_DEVICE, handle, 1,
> -				     acpi_i2c_add_device, NULL,
> -				     adap, NULL);
> -	if (ACPI_FAILURE(status))
> -		dev_warn(&adap->dev, "failed to enumerate I2C slaves\n");
> -}
> -
> -#ifdef CONFIG_ACPI_I2C_OPREGION
> -static int acpi_gsb_i2c_read_bytes(struct i2c_client *client,
> -		u8 cmd, u8 *data, u8 data_len)
> -{
> -
> -	struct i2c_msg msgs[2];
> -	int ret;
> -	u8 *buffer;
> -
> -	buffer = kzalloc(data_len, GFP_KERNEL);
> -	if (!buffer)
> -		return AE_NO_MEMORY;
> -
> -	msgs[0].addr = client->addr;
> -	msgs[0].flags = client->flags;
> -	msgs[0].len = 1;
> -	msgs[0].buf = &cmd;
> -
> -	msgs[1].addr = client->addr;
> -	msgs[1].flags = client->flags | I2C_M_RD;
> -	msgs[1].len = data_len;
> -	msgs[1].buf = buffer;
> -
> -	ret = i2c_transfer(client->adapter, msgs, ARRAY_SIZE(msgs));
> -	if (ret < 0)
> -		dev_err(&client->adapter->dev, "i2c read failed\n");
> -	else
> -		memcpy(data, buffer, data_len);
> -
> -	kfree(buffer);
> -	return ret;
> -}
> -
> -static int acpi_gsb_i2c_write_bytes(struct i2c_client *client,
> -		u8 cmd, u8 *data, u8 data_len)
> -{
> -
> -	struct i2c_msg msgs[1];
> -	u8 *buffer;
> -	int ret = AE_OK;
> -
> -	buffer = kzalloc(data_len + 1, GFP_KERNEL);
> -	if (!buffer)
> -		return AE_NO_MEMORY;
> -
> -	buffer[0] = cmd;
> -	memcpy(buffer + 1, data, data_len);
> -
> -	msgs[0].addr = client->addr;
> -	msgs[0].flags = client->flags;
> -	msgs[0].len = data_len + 1;
> -	msgs[0].buf = buffer;
> -
> -	ret = i2c_transfer(client->adapter, msgs, ARRAY_SIZE(msgs));
> -	if (ret < 0)
> -		dev_err(&client->adapter->dev, "i2c write failed\n");
> -
> -	kfree(buffer);
> -	return ret;
> -}
> -
> -static acpi_status
> -acpi_i2c_space_handler(u32 function, acpi_physical_address command,
> -			u32 bits, u64 *value64,
> -			void *handler_context, void *region_context)
> -{
> -	struct gsb_buffer *gsb = (struct gsb_buffer *)value64;
> -	struct acpi_i2c_handler_data *data = handler_context;
> -	struct acpi_connection_info *info = &data->info;
> -	struct acpi_resource_i2c_serialbus *sb;
> -	struct i2c_adapter *adapter = data->adapter;
> -	struct i2c_client client;
> -	struct acpi_resource *ares;
> -	u32 accessor_type = function >> 16;
> -	u8 action = function & ACPI_IO_MASK;
> -	acpi_status ret = AE_OK;
> -	int status;
> -
> -	ret = acpi_buffer_to_resource(info->connection, info->length, &ares);
> -	if (ACPI_FAILURE(ret))
> -		return ret;
> -
> -	if (!value64 || ares->type != ACPI_RESOURCE_TYPE_SERIAL_BUS) {
> -		ret = AE_BAD_PARAMETER;
> -		goto err;
> -	}
> -
> -	sb = &ares->data.i2c_serial_bus;
> -	if (sb->type != ACPI_RESOURCE_SERIAL_TYPE_I2C) {
> -		ret = AE_BAD_PARAMETER;
> -		goto err;
> -	}
> -
> -	memset(&client, 0, sizeof(client));
> -	client.adapter = adapter;
> -	client.addr = sb->slave_address;
> -	client.flags = 0;
> -
> -	if (sb->access_mode == ACPI_I2C_10BIT_MODE)
> -		client.flags |= I2C_CLIENT_TEN;
> -
> -	switch (accessor_type) {
> -	case ACPI_GSB_ACCESS_ATTRIB_SEND_RCV:
> -		if (action == ACPI_READ) {
> -			status = i2c_smbus_read_byte(&client);
> -			if (status >= 0) {
> -				gsb->bdata = status;
> -				status = 0;
> -			}
> -		} else {
> -			status = i2c_smbus_write_byte(&client, gsb->bdata);
> -		}
> -		break;
> -
> -	case ACPI_GSB_ACCESS_ATTRIB_BYTE:
> -		if (action == ACPI_READ) {
> -			status = i2c_smbus_read_byte_data(&client, command);
> -			if (status >= 0) {
> -				gsb->bdata = status;
> -				status = 0;
> -			}
> -		} else {
> -			status = i2c_smbus_write_byte_data(&client, command,
> -					gsb->bdata);
> -		}
> -		break;
> -
> -	case ACPI_GSB_ACCESS_ATTRIB_WORD:
> -		if (action == ACPI_READ) {
> -			status = i2c_smbus_read_word_data(&client, command);
> -			if (status >= 0) {
> -				gsb->wdata = status;
> -				status = 0;
> -			}
> -		} else {
> -			status = i2c_smbus_write_word_data(&client, command,
> -					gsb->wdata);
> -		}
> -		break;
> -
> -	case ACPI_GSB_ACCESS_ATTRIB_BLOCK:
> -		if (action == ACPI_READ) {
> -			status = i2c_smbus_read_block_data(&client, command,
> -					gsb->data);
> -			if (status >= 0) {
> -				gsb->len = status;
> -				status = 0;
> -			}
> -		} else {
> -			status = i2c_smbus_write_block_data(&client, command,
> -					gsb->len, gsb->data);
> -		}
> -		break;
> -
> -	case ACPI_GSB_ACCESS_ATTRIB_MULTIBYTE:
> -		if (action == ACPI_READ) {
> -			status = acpi_gsb_i2c_read_bytes(&client, command,
> -					gsb->data, info->access_length);
> -			if (status > 0)
> -				status = 0;
> -		} else {
> -			status = acpi_gsb_i2c_write_bytes(&client, command,
> -					gsb->data, info->access_length);
> -		}
> -		break;
> -
> -	default:
> -		pr_info("protocol(0x%02x) is not supported.\n", accessor_type);
> -		ret = AE_BAD_PARAMETER;
> -		goto err;
> -	}
> -
> -	gsb->status = status;
> -
> - err:
> -	ACPI_FREE(ares);
> -	return ret;
> -}
> -
> -
> -int acpi_i2c_install_space_handler(struct i2c_adapter *adapter)
> -{
> -	acpi_handle handle = ACPI_HANDLE(adapter->dev.parent);
> -	struct acpi_i2c_handler_data *data;
> -	acpi_status status;
> -
> -	if (!handle)
> -		return -ENODEV;
> -
> -	data = kzalloc(sizeof(struct acpi_i2c_handler_data),
> -			    GFP_KERNEL);
> -	if (!data)
> -		return -ENOMEM;
> -
> -	data->adapter = adapter;
> -	status = acpi_bus_attach_private_data(handle, (void *)data);
> -	if (ACPI_FAILURE(status)) {
> -		kfree(data);
> -		return -ENOMEM;
> -	}
> -
> -	status = acpi_install_address_space_handler(handle,
> -				ACPI_ADR_SPACE_GSBUS,
> -				&acpi_i2c_space_handler,
> -				NULL,
> -				data);
> -	if (ACPI_FAILURE(status)) {
> -		dev_err(&adapter->dev, "Error installing i2c space handler\n");
> -		acpi_bus_detach_private_data(handle);
> -		kfree(data);
> -		return -ENOMEM;
> -	}
> -
> -	return 0;
> -}
> -
> -void acpi_i2c_remove_space_handler(struct i2c_adapter *adapter)
> -{
> -	acpi_handle handle = ACPI_HANDLE(adapter->dev.parent);
> -	struct acpi_i2c_handler_data *data;
> -	acpi_status status;
> -
> -	if (!handle)
> -		return;
> -
> -	acpi_remove_address_space_handler(handle,
> -				ACPI_ADR_SPACE_GSBUS,
> -				&acpi_i2c_space_handler);
> -
> -	status = acpi_bus_get_private_data(handle, (void **)&data);
> -	if (ACPI_SUCCESS(status))
> -		kfree(data);
> -
> -	acpi_bus_detach_private_data(handle);
> -}
> -#endif
> diff --git a/drivers/i2c/i2c-core.c b/drivers/i2c/i2c-core.c
> index 632057a44615..3fbd5d5c38bf 100644
> --- a/drivers/i2c/i2c-core.c
> +++ b/drivers/i2c/i2c-core.c
> @@ -27,6 +27,8 @@
>     OF support is copyright (c) 2008 Jochen Friedrich <jochen@scram.de>
>     (based on a previous patch from Jon Smirl <jonsmirl-Re5JQEeQqe8AvxtiuMwx3w@public.gmane.org>) and
>     (c) 2013  Wolfram Sang <wsa-z923LK4zBo2bacvFa/9K2g@public.gmane.org>
> +   I2C ACPI code Copyright (C) 2014 Intel Corp
> +   Author: Lan Tianyu <tianyu.lan-ral2JQCrhuEAvxtiuMwx3w@public.gmane.org>
>   */
>  
>  #include <linux/module.h>
> @@ -78,6 +80,349 @@ void i2c_transfer_trace_unreg(void)
>  	static_key_slow_dec(&i2c_trace_msg);
>  }
>  
> +#if defined(CONFIG_ACPI)
> +struct acpi_i2c_handler_data {
> +	struct acpi_connection_info info;
> +	struct i2c_adapter *adapter;
> +};
> +
> +struct gsb_buffer {
> +	u8	status;
> +	u8	len;
> +	union {
> +		u16	wdata;
> +		u8	bdata;
> +		u8	data[0];
> +	};
> +} __packed;
> +
> +static int acpi_i2c_add_resource(struct acpi_resource *ares, void *data)
> +{
> +	struct i2c_board_info *info = data;
> +
> +	if (ares->type == ACPI_RESOURCE_TYPE_SERIAL_BUS) {
> +		struct acpi_resource_i2c_serialbus *sb;
> +
> +		sb = &ares->data.i2c_serial_bus;
> +		if (sb->type == ACPI_RESOURCE_SERIAL_TYPE_I2C) {
> +			info->addr = sb->slave_address;
> +			if (sb->access_mode == ACPI_I2C_10BIT_MODE)
> +				info->flags |= I2C_CLIENT_TEN;
> +		}
> +	} else if (info->irq < 0) {
> +		struct resource r;
> +
> +		if (acpi_dev_resource_interrupt(ares, 0, &r))
> +			info->irq = r.start;
> +	}
> +
> +	/* Tell the ACPI core to skip this resource */
> +	return 1;
> +}
> +
> +static acpi_status acpi_i2c_add_device(acpi_handle handle, u32 level,
> +				       void *data, void **return_value)
> +{
> +	struct i2c_adapter *adapter = data;
> +	struct list_head resource_list;
> +	struct i2c_board_info info;
> +	struct acpi_device *adev;
> +	int ret;
> +
> +	if (acpi_bus_get_device(handle, &adev))
> +		return AE_OK;
> +	if (acpi_bus_get_status(adev) || !adev->status.present)
> +		return AE_OK;
> +
> +	memset(&info, 0, sizeof(info));
> +	info.acpi_node.companion = adev;
> +	info.irq = -1;
> +
> +	INIT_LIST_HEAD(&resource_list);
> +	ret = acpi_dev_get_resources(adev, &resource_list,
> +				     acpi_i2c_add_resource, &info);
> +	acpi_dev_free_resource_list(&resource_list);
> +
> +	if (ret < 0 || !info.addr)
> +		return AE_OK;
> +
> +	adev->power.flags.ignore_parent = true;
> +	strlcpy(info.type, dev_name(&adev->dev), sizeof(info.type));
> +	if (!i2c_new_device(adapter, &info)) {
> +		adev->power.flags.ignore_parent = false;
> +		dev_err(&adapter->dev,
> +			"failed to add I2C device %s from ACPI\n",
> +			dev_name(&adev->dev));
> +	}
> +
> +	return AE_OK;
> +}
> +
> +/**
> + * acpi_i2c_register_devices - enumerate I2C slave devices behind adapter
> + * @adap: pointer to adapter
> + *
> + * Enumerate all I2C slave devices behind this adapter by walking the ACPI
> + * namespace. When a device is found it will be added to the Linux device
> + * model and bound to the corresponding ACPI handle.
> + */
> +void acpi_i2c_register_devices(struct i2c_adapter *adap)
> +{
> +	acpi_handle handle;
> +	acpi_status status;
> +
> +	if (!adap->dev.parent)
> +		return;
> +
> +	handle = ACPI_HANDLE(adap->dev.parent);
> +	if (!handle)
> +		return;
> +
> +	status = acpi_walk_namespace(ACPI_TYPE_DEVICE, handle, 1,
> +				     acpi_i2c_add_device, NULL,
> +				     adap, NULL);
> +	if (ACPI_FAILURE(status))
> +		dev_warn(&adap->dev, "failed to enumerate I2C slaves\n");
> +}
> +
> +#ifdef CONFIG_ACPI_I2C_OPREGION
> +static int acpi_gsb_i2c_read_bytes(struct i2c_client *client,
> +		u8 cmd, u8 *data, u8 data_len)
> +{
> +
> +	struct i2c_msg msgs[2];
> +	int ret;
> +	u8 *buffer;
> +
> +	buffer = kzalloc(data_len, GFP_KERNEL);
> +	if (!buffer)
> +		return AE_NO_MEMORY;
> +
> +	msgs[0].addr = client->addr;
> +	msgs[0].flags = client->flags;
> +	msgs[0].len = 1;
> +	msgs[0].buf = &cmd;
> +
> +	msgs[1].addr = client->addr;
> +	msgs[1].flags = client->flags | I2C_M_RD;
> +	msgs[1].len = data_len;
> +	msgs[1].buf = buffer;
> +
> +	ret = i2c_transfer(client->adapter, msgs, ARRAY_SIZE(msgs));
> +	if (ret < 0)
> +		dev_err(&client->adapter->dev, "i2c read failed\n");
> +	else
> +		memcpy(data, buffer, data_len);
> +
> +	kfree(buffer);
> +	return ret;
> +}
> +
> +static int acpi_gsb_i2c_write_bytes(struct i2c_client *client,
> +		u8 cmd, u8 *data, u8 data_len)
> +{
> +
> +	struct i2c_msg msgs[1];
> +	u8 *buffer;
> +	int ret = AE_OK;
> +
> +	buffer = kzalloc(data_len + 1, GFP_KERNEL);
> +	if (!buffer)
> +		return AE_NO_MEMORY;
> +
> +	buffer[0] = cmd;
> +	memcpy(buffer + 1, data, data_len);
> +
> +	msgs[0].addr = client->addr;
> +	msgs[0].flags = client->flags;
> +	msgs[0].len = data_len + 1;
> +	msgs[0].buf = buffer;
> +
> +	ret = i2c_transfer(client->adapter, msgs, ARRAY_SIZE(msgs));
> +	if (ret < 0)
> +		dev_err(&client->adapter->dev, "i2c write failed\n");
> +
> +	kfree(buffer);
> +	return ret;
> +}
> +
> +static acpi_status
> +acpi_i2c_space_handler(u32 function, acpi_physical_address command,
> +			u32 bits, u64 *value64,
> +			void *handler_context, void *region_context)
> +{
> +	struct gsb_buffer *gsb = (struct gsb_buffer *)value64;
> +	struct acpi_i2c_handler_data *data = handler_context;
> +	struct acpi_connection_info *info = &data->info;
> +	struct acpi_resource_i2c_serialbus *sb;
> +	struct i2c_adapter *adapter = data->adapter;
> +	struct i2c_client client;
> +	struct acpi_resource *ares;
> +	u32 accessor_type = function >> 16;
> +	u8 action = function & ACPI_IO_MASK;
> +	acpi_status ret = AE_OK;
> +	int status;
> +
> +	ret = acpi_buffer_to_resource(info->connection, info->length, &ares);
> +	if (ACPI_FAILURE(ret))
> +		return ret;
> +
> +	if (!value64 || ares->type != ACPI_RESOURCE_TYPE_SERIAL_BUS) {
> +		ret = AE_BAD_PARAMETER;
> +		goto err;
> +	}
> +
> +	sb = &ares->data.i2c_serial_bus;
> +	if (sb->type != ACPI_RESOURCE_SERIAL_TYPE_I2C) {
> +		ret = AE_BAD_PARAMETER;
> +		goto err;
> +	}
> +
> +	memset(&client, 0, sizeof(client));
> +	client.adapter = adapter;
> +	client.addr = sb->slave_address;
> +	client.flags = 0;
> +
> +	if (sb->access_mode == ACPI_I2C_10BIT_MODE)
> +		client.flags |= I2C_CLIENT_TEN;
> +
> +	switch (accessor_type) {
> +	case ACPI_GSB_ACCESS_ATTRIB_SEND_RCV:
> +		if (action == ACPI_READ) {
> +			status = i2c_smbus_read_byte(&client);
> +			if (status >= 0) {
> +				gsb->bdata = status;
> +				status = 0;
> +			}
> +		} else {
> +			status = i2c_smbus_write_byte(&client, gsb->bdata);
> +		}
> +		break;
> +
> +	case ACPI_GSB_ACCESS_ATTRIB_BYTE:
> +		if (action == ACPI_READ) {
> +			status = i2c_smbus_read_byte_data(&client, command);
> +			if (status >= 0) {
> +				gsb->bdata = status;
> +				status = 0;
> +			}
> +		} else {
> +			status = i2c_smbus_write_byte_data(&client, command,
> +					gsb->bdata);
> +		}
> +		break;
> +
> +	case ACPI_GSB_ACCESS_ATTRIB_WORD:
> +		if (action == ACPI_READ) {
> +			status = i2c_smbus_read_word_data(&client, command);
> +			if (status >= 0) {
> +				gsb->wdata = status;
> +				status = 0;
> +			}
> +		} else {
> +			status = i2c_smbus_write_word_data(&client, command,
> +					gsb->wdata);
> +		}
> +		break;
> +
> +	case ACPI_GSB_ACCESS_ATTRIB_BLOCK:
> +		if (action == ACPI_READ) {
> +			status = i2c_smbus_read_block_data(&client, command,
> +					gsb->data);
> +			if (status >= 0) {
> +				gsb->len = status;
> +				status = 0;
> +			}
> +		} else {
> +			status = i2c_smbus_write_block_data(&client, command,
> +					gsb->len, gsb->data);
> +		}
> +		break;
> +
> +	case ACPI_GSB_ACCESS_ATTRIB_MULTIBYTE:
> +		if (action == ACPI_READ) {
> +			status = acpi_gsb_i2c_read_bytes(&client, command,
> +					gsb->data, info->access_length);
> +			if (status > 0)
> +				status = 0;
> +		} else {
> +			status = acpi_gsb_i2c_write_bytes(&client, command,
> +					gsb->data, info->access_length);
> +		}
> +		break;
> +
> +	default:
> +		pr_info("protocol(0x%02x) is not supported.\n", accessor_type);
> +		ret = AE_BAD_PARAMETER;
> +		goto err;
> +	}
> +
> +	gsb->status = status;
> +
> + err:
> +	ACPI_FREE(ares);
> +	return ret;
> +}
> +
> +
> +int acpi_i2c_install_space_handler(struct i2c_adapter *adapter)
> +{
> +	acpi_handle handle = ACPI_HANDLE(adapter->dev.parent);
> +	struct acpi_i2c_handler_data *data;
> +	acpi_status status;
> +
> +	if (!handle)
> +		return -ENODEV;
> +
> +	data = kzalloc(sizeof(struct acpi_i2c_handler_data),
> +			    GFP_KERNEL);
> +	if (!data)
> +		return -ENOMEM;
> +
> +	data->adapter = adapter;
> +	status = acpi_bus_attach_private_data(handle, (void *)data);
> +	if (ACPI_FAILURE(status)) {
> +		kfree(data);
> +		return -ENOMEM;
> +	}
> +
> +	status = acpi_install_address_space_handler(handle,
> +				ACPI_ADR_SPACE_GSBUS,
> +				&acpi_i2c_space_handler,
> +				NULL,
> +				data);
> +	if (ACPI_FAILURE(status)) {
> +		dev_err(&adapter->dev, "Error installing i2c space handler\n");
> +		acpi_bus_detach_private_data(handle);
> +		kfree(data);
> +		return -ENOMEM;
> +	}
> +
> +	return 0;
> +}
> +
> +void acpi_i2c_remove_space_handler(struct i2c_adapter *adapter)
> +{
> +	acpi_handle handle = ACPI_HANDLE(adapter->dev.parent);
> +	struct acpi_i2c_handler_data *data;
> +	acpi_status status;
> +
> +	if (!handle)
> +		return;
> +
> +	acpi_remove_address_space_handler(handle,
> +				ACPI_ADR_SPACE_GSBUS,
> +				&acpi_i2c_space_handler);
> +
> +	status = acpi_bus_get_private_data(handle, (void **)&data);
> +	if (ACPI_SUCCESS(status))
> +		kfree(data);
> +
> +	acpi_bus_detach_private_data(handle);
> +}
> +#endif
> +#endif /* CONFIG_ACPI */
> +
>  /* ------------------------------------------------------------------------- */
>  
>  static const struct i2c_device_id *i2c_match_id(const struct i2c_device_id *id,
> 


-- 
Best regards
Tianyu Lan

Re: [PATCH] i2c: move acpi code back into the core

[Lan Tianyu]

On 2014年09月23日 05:06, Wolfram Sang wrote:
> Commit 5d98e61d337c ("I2C/ACPI: Add i2c ACPI operation region support") renamed
> the i2c-core module. This may cause regressions for distributions, so put the
> ACPI code back into the core. No code was changed.
> 
> Reported-by: Jean Delvare <jdelvare@suse.de>
> Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
> Cc: Mika Westerberg <mika.westerberg@linux.intel.com>
> Cc: Lan Tianyu <tianyu.lan@intel.com>
> Cc: Jean Delvare <jdelvare@suse.de>
> ---
> 
> Lan Tianyi, this is a patch I expected to get from you, fully tested. Since we
> are approaching the final release soon, I did it now. Please do test this
> patch. All I can do is build test (it works for me, build robots are still
> running). If nobody tests this, I have to revert the ACPI changes of this
> cycle.

Hi Wolfram:

Sorry for later response due to sickness. I can't write this patch in
time. Sorry again. I will test it soon.

> 
> Jean, can you have a look, too?
> 
> We can think of something better for the next release, but for now, this should be it.
> 
>  MAINTAINERS            |   1 -
>  drivers/i2c/Makefile   |   5 +-
>  drivers/i2c/i2c-acpi.c | 364 -------------------------------------------------
>  drivers/i2c/i2c-core.c | 345 ++++++++++++++++++++++++++++++++++++++++++++++
>  4 files changed, 346 insertions(+), 369 deletions(-)
>  delete mode 100644 drivers/i2c/i2c-acpi.c
> 
> diff --git a/MAINTAINERS b/MAINTAINERS
> index 809ecd680d88..e3682d0dea1e 100644
> --- a/MAINTAINERS
> +++ b/MAINTAINERS
> @@ -4477,7 +4477,6 @@ M:	Mika Westerberg <mika.westerberg@linux.intel.com>
>  L:	linux-i2c@vger.kernel.org
>  L:	linux-acpi@vger.kernel.org
>  S:	Maintained
> -F:	drivers/i2c/i2c-acpi.c
>  
>  I2C-TAOS-EVM DRIVER
>  M:	Jean Delvare <jdelvare@suse.de>
> diff --git a/drivers/i2c/Makefile b/drivers/i2c/Makefile
> index e0228b228256..1722f50f2473 100644
> --- a/drivers/i2c/Makefile
> +++ b/drivers/i2c/Makefile
> @@ -2,11 +2,8 @@
>  # Makefile for the i2c core.
>  #
>  
> -i2ccore-y := i2c-core.o
> -i2ccore-$(CONFIG_ACPI)	 	+= i2c-acpi.o
> -
>  obj-$(CONFIG_I2C_BOARDINFO)	+= i2c-boardinfo.o
> -obj-$(CONFIG_I2C)		+= i2ccore.o
> +obj-$(CONFIG_I2C)		+= i2c-core.o
>  obj-$(CONFIG_I2C_SMBUS)		+= i2c-smbus.o
>  obj-$(CONFIG_I2C_CHARDEV)	+= i2c-dev.o
>  obj-$(CONFIG_I2C_MUX)		+= i2c-mux.o
> diff --git a/drivers/i2c/i2c-acpi.c b/drivers/i2c/i2c-acpi.c
> deleted file mode 100644
> index 0dbc18c15c43..000000000000
> --- a/drivers/i2c/i2c-acpi.c
> +++ /dev/null
> @@ -1,364 +0,0 @@
> -/*
> - * I2C ACPI code
> - *
> - * Copyright (C) 2014 Intel Corp
> - *
> - * Author: Lan Tianyu <tianyu.lan@intel.com>
> - *
> - * This program is free software; you can redistribute it and/or modify
> - * it under the terms of the GNU General Public License version 2 as
> - * published by the Free Software Foundation.
> - *
> - * This program is distributed in the hope that it will be useful, but
> - * WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY
> - * or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
> - * for more details.
> - */
> -#define pr_fmt(fmt) "I2C/ACPI : " fmt
> -
> -#include <linux/kernel.h>
> -#include <linux/errno.h>
> -#include <linux/err.h>
> -#include <linux/i2c.h>
> -#include <linux/acpi.h>
> -
> -struct acpi_i2c_handler_data {
> -	struct acpi_connection_info info;
> -	struct i2c_adapter *adapter;
> -};
> -
> -struct gsb_buffer {
> -	u8	status;
> -	u8	len;
> -	union {
> -		u16	wdata;
> -		u8	bdata;
> -		u8	data[0];
> -	};
> -} __packed;
> -
> -static int acpi_i2c_add_resource(struct acpi_resource *ares, void *data)
> -{
> -	struct i2c_board_info *info = data;
> -
> -	if (ares->type == ACPI_RESOURCE_TYPE_SERIAL_BUS) {
> -		struct acpi_resource_i2c_serialbus *sb;
> -
> -		sb = &ares->data.i2c_serial_bus;
> -		if (sb->type == ACPI_RESOURCE_SERIAL_TYPE_I2C) {
> -			info->addr = sb->slave_address;
> -			if (sb->access_mode == ACPI_I2C_10BIT_MODE)
> -				info->flags |= I2C_CLIENT_TEN;
> -		}
> -	} else if (info->irq < 0) {
> -		struct resource r;
> -
> -		if (acpi_dev_resource_interrupt(ares, 0, &r))
> -			info->irq = r.start;
> -	}
> -
> -	/* Tell the ACPI core to skip this resource */
> -	return 1;
> -}
> -
> -static acpi_status acpi_i2c_add_device(acpi_handle handle, u32 level,
> -				       void *data, void **return_value)
> -{
> -	struct i2c_adapter *adapter = data;
> -	struct list_head resource_list;
> -	struct i2c_board_info info;
> -	struct acpi_device *adev;
> -	int ret;
> -
> -	if (acpi_bus_get_device(handle, &adev))
> -		return AE_OK;
> -	if (acpi_bus_get_status(adev) || !adev->status.present)
> -		return AE_OK;
> -
> -	memset(&info, 0, sizeof(info));
> -	info.acpi_node.companion = adev;
> -	info.irq = -1;
> -
> -	INIT_LIST_HEAD(&resource_list);
> -	ret = acpi_dev_get_resources(adev, &resource_list,
> -				     acpi_i2c_add_resource, &info);
> -	acpi_dev_free_resource_list(&resource_list);
> -
> -	if (ret < 0 || !info.addr)
> -		return AE_OK;
> -
> -	adev->power.flags.ignore_parent = true;
> -	strlcpy(info.type, dev_name(&adev->dev), sizeof(info.type));
> -	if (!i2c_new_device(adapter, &info)) {
> -		adev->power.flags.ignore_parent = false;
> -		dev_err(&adapter->dev,
> -			"failed to add I2C device %s from ACPI\n",
> -			dev_name(&adev->dev));
> -	}
> -
> -	return AE_OK;
> -}
> -
> -/**
> - * acpi_i2c_register_devices - enumerate I2C slave devices behind adapter
> - * @adap: pointer to adapter
> - *
> - * Enumerate all I2C slave devices behind this adapter by walking the ACPI
> - * namespace. When a device is found it will be added to the Linux device
> - * model and bound to the corresponding ACPI handle.
> - */
> -void acpi_i2c_register_devices(struct i2c_adapter *adap)
> -{
> -	acpi_handle handle;
> -	acpi_status status;
> -
> -	if (!adap->dev.parent)
> -		return;
> -
> -	handle = ACPI_HANDLE(adap->dev.parent);
> -	if (!handle)
> -		return;
> -
> -	status = acpi_walk_namespace(ACPI_TYPE_DEVICE, handle, 1,
> -				     acpi_i2c_add_device, NULL,
> -				     adap, NULL);
> -	if (ACPI_FAILURE(status))
> -		dev_warn(&adap->dev, "failed to enumerate I2C slaves\n");
> -}
> -
> -#ifdef CONFIG_ACPI_I2C_OPREGION
> -static int acpi_gsb_i2c_read_bytes(struct i2c_client *client,
> -		u8 cmd, u8 *data, u8 data_len)
> -{
> -
> -	struct i2c_msg msgs[2];
> -	int ret;
> -	u8 *buffer;
> -
> -	buffer = kzalloc(data_len, GFP_KERNEL);
> -	if (!buffer)
> -		return AE_NO_MEMORY;
> -
> -	msgs[0].addr = client->addr;
> -	msgs[0].flags = client->flags;
> -	msgs[0].len = 1;
> -	msgs[0].buf = &cmd;
> -
> -	msgs[1].addr = client->addr;
> -	msgs[1].flags = client->flags | I2C_M_RD;
> -	msgs[1].len = data_len;
> -	msgs[1].buf = buffer;
> -
> -	ret = i2c_transfer(client->adapter, msgs, ARRAY_SIZE(msgs));
> -	if (ret < 0)
> -		dev_err(&client->adapter->dev, "i2c read failed\n");
> -	else
> -		memcpy(data, buffer, data_len);
> -
> -	kfree(buffer);
> -	return ret;
> -}
> -
> -static int acpi_gsb_i2c_write_bytes(struct i2c_client *client,
> -		u8 cmd, u8 *data, u8 data_len)
> -{
> -
> -	struct i2c_msg msgs[1];
> -	u8 *buffer;
> -	int ret = AE_OK;
> -
> -	buffer = kzalloc(data_len + 1, GFP_KERNEL);
> -	if (!buffer)
> -		return AE_NO_MEMORY;
> -
> -	buffer[0] = cmd;
> -	memcpy(buffer + 1, data, data_len);
> -
> -	msgs[0].addr = client->addr;
> -	msgs[0].flags = client->flags;
> -	msgs[0].len = data_len + 1;
> -	msgs[0].buf = buffer;
> -
> -	ret = i2c_transfer(client->adapter, msgs, ARRAY_SIZE(msgs));
> -	if (ret < 0)
> -		dev_err(&client->adapter->dev, "i2c write failed\n");
> -
> -	kfree(buffer);
> -	return ret;
> -}
> -
> -static acpi_status
> -acpi_i2c_space_handler(u32 function, acpi_physical_address command,
> -			u32 bits, u64 *value64,
> -			void *handler_context, void *region_context)
> -{
> -	struct gsb_buffer *gsb = (struct gsb_buffer *)value64;
> -	struct acpi_i2c_handler_data *data = handler_context;
> -	struct acpi_connection_info *info = &data->info;
> -	struct acpi_resource_i2c_serialbus *sb;
> -	struct i2c_adapter *adapter = data->adapter;
> -	struct i2c_client client;
> -	struct acpi_resource *ares;
> -	u32 accessor_type = function >> 16;
> -	u8 action = function & ACPI_IO_MASK;
> -	acpi_status ret = AE_OK;
> -	int status;
> -
> -	ret = acpi_buffer_to_resource(info->connection, info->length, &ares);
> -	if (ACPI_FAILURE(ret))
> -		return ret;
> -
> -	if (!value64 || ares->type != ACPI_RESOURCE_TYPE_SERIAL_BUS) {
> -		ret = AE_BAD_PARAMETER;
> -		goto err;
> -	}
> -
> -	sb = &ares->data.i2c_serial_bus;
> -	if (sb->type != ACPI_RESOURCE_SERIAL_TYPE_I2C) {
> -		ret = AE_BAD_PARAMETER;
> -		goto err;
> -	}
> -
> -	memset(&client, 0, sizeof(client));
> -	client.adapter = adapter;
> -	client.addr = sb->slave_address;
> -	client.flags = 0;
> -
> -	if (sb->access_mode == ACPI_I2C_10BIT_MODE)
> -		client.flags |= I2C_CLIENT_TEN;
> -
> -	switch (accessor_type) {
> -	case ACPI_GSB_ACCESS_ATTRIB_SEND_RCV:
> -		if (action == ACPI_READ) {
> -			status = i2c_smbus_read_byte(&client);
> -			if (status >= 0) {
> -				gsb->bdata = status;
> -				status = 0;
> -			}
> -		} else {
> -			status = i2c_smbus_write_byte(&client, gsb->bdata);
> -		}
> -		break;
> -
> -	case ACPI_GSB_ACCESS_ATTRIB_BYTE:
> -		if (action == ACPI_READ) {
> -			status = i2c_smbus_read_byte_data(&client, command);
> -			if (status >= 0) {
> -				gsb->bdata = status;
> -				status = 0;
> -			}
> -		} else {
> -			status = i2c_smbus_write_byte_data(&client, command,
> -					gsb->bdata);
> -		}
> -		break;
> -
> -	case ACPI_GSB_ACCESS_ATTRIB_WORD:
> -		if (action == ACPI_READ) {
> -			status = i2c_smbus_read_word_data(&client, command);
> -			if (status >= 0) {
> -				gsb->wdata = status;
> -				status = 0;
> -			}
> -		} else {
> -			status = i2c_smbus_write_word_data(&client, command,
> -					gsb->wdata);
> -		}
> -		break;
> -
> -	case ACPI_GSB_ACCESS_ATTRIB_BLOCK:
> -		if (action == ACPI_READ) {
> -			status = i2c_smbus_read_block_data(&client, command,
> -					gsb->data);
> -			if (status >= 0) {
> -				gsb->len = status;
> -				status = 0;
> -			}
> -		} else {
> -			status = i2c_smbus_write_block_data(&client, command,
> -					gsb->len, gsb->data);
> -		}
> -		break;
> -
> -	case ACPI_GSB_ACCESS_ATTRIB_MULTIBYTE:
> -		if (action == ACPI_READ) {
> -			status = acpi_gsb_i2c_read_bytes(&client, command,
> -					gsb->data, info->access_length);
> -			if (status > 0)
> -				status = 0;
> -		} else {
> -			status = acpi_gsb_i2c_write_bytes(&client, command,
> -					gsb->data, info->access_length);
> -		}
> -		break;
> -
> -	default:
> -		pr_info("protocol(0x%02x) is not supported.\n", accessor_type);
> -		ret = AE_BAD_PARAMETER;
> -		goto err;
> -	}
> -
> -	gsb->status = status;
> -
> - err:
> -	ACPI_FREE(ares);
> -	return ret;
> -}
> -
> -
> -int acpi_i2c_install_space_handler(struct i2c_adapter *adapter)
> -{
> -	acpi_handle handle = ACPI_HANDLE(adapter->dev.parent);
> -	struct acpi_i2c_handler_data *data;
> -	acpi_status status;
> -
> -	if (!handle)
> -		return -ENODEV;
> -
> -	data = kzalloc(sizeof(struct acpi_i2c_handler_data),
> -			    GFP_KERNEL);
> -	if (!data)
> -		return -ENOMEM;
> -
> -	data->adapter = adapter;
> -	status = acpi_bus_attach_private_data(handle, (void *)data);
> -	if (ACPI_FAILURE(status)) {
> -		kfree(data);
> -		return -ENOMEM;
> -	}
> -
> -	status = acpi_install_address_space_handler(handle,
> -				ACPI_ADR_SPACE_GSBUS,
> -				&acpi_i2c_space_handler,
> -				NULL,
> -				data);
> -	if (ACPI_FAILURE(status)) {
> -		dev_err(&adapter->dev, "Error installing i2c space handler\n");
> -		acpi_bus_detach_private_data(handle);
> -		kfree(data);
> -		return -ENOMEM;
> -	}
> -
> -	return 0;
> -}
> -
> -void acpi_i2c_remove_space_handler(struct i2c_adapter *adapter)
> -{
> -	acpi_handle handle = ACPI_HANDLE(adapter->dev.parent);
> -	struct acpi_i2c_handler_data *data;
> -	acpi_status status;
> -
> -	if (!handle)
> -		return;
> -
> -	acpi_remove_address_space_handler(handle,
> -				ACPI_ADR_SPACE_GSBUS,
> -				&acpi_i2c_space_handler);
> -
> -	status = acpi_bus_get_private_data(handle, (void **)&data);
> -	if (ACPI_SUCCESS(status))
> -		kfree(data);
> -
> -	acpi_bus_detach_private_data(handle);
> -}
> -#endif
> diff --git a/drivers/i2c/i2c-core.c b/drivers/i2c/i2c-core.c
> index 632057a44615..3fbd5d5c38bf 100644
> --- a/drivers/i2c/i2c-core.c
> +++ b/drivers/i2c/i2c-core.c
> @@ -27,6 +27,8 @@
>     OF support is copyright (c) 2008 Jochen Friedrich <jochen@scram.de>
>     (based on a previous patch from Jon Smirl <jonsmirl@gmail.com>) and
>     (c) 2013  Wolfram Sang <wsa@the-dreams.de>
> +   I2C ACPI code Copyright (C) 2014 Intel Corp
> +   Author: Lan Tianyu <tianyu.lan@intel.com>
>   */
>  
>  #include <linux/module.h>
> @@ -78,6 +80,349 @@ void i2c_transfer_trace_unreg(void)
>  	static_key_slow_dec(&i2c_trace_msg);
>  }
>  
> +#if defined(CONFIG_ACPI)
> +struct acpi_i2c_handler_data {
> +	struct acpi_connection_info info;
> +	struct i2c_adapter *adapter;
> +};
> +
> +struct gsb_buffer {
> +	u8	status;
> +	u8	len;
> +	union {
> +		u16	wdata;
> +		u8	bdata;
> +		u8	data[0];
> +	};
> +} __packed;
> +
> +static int acpi_i2c_add_resource(struct acpi_resource *ares, void *data)
> +{
> +	struct i2c_board_info *info = data;
> +
> +	if (ares->type == ACPI_RESOURCE_TYPE_SERIAL_BUS) {
> +		struct acpi_resource_i2c_serialbus *sb;
> +
> +		sb = &ares->data.i2c_serial_bus;
> +		if (sb->type == ACPI_RESOURCE_SERIAL_TYPE_I2C) {
> +			info->addr = sb->slave_address;
> +			if (sb->access_mode == ACPI_I2C_10BIT_MODE)
> +				info->flags |= I2C_CLIENT_TEN;
> +		}
> +	} else if (info->irq < 0) {
> +		struct resource r;
> +
> +		if (acpi_dev_resource_interrupt(ares, 0, &r))
> +			info->irq = r.start;
> +	}
> +
> +	/* Tell the ACPI core to skip this resource */
> +	return 1;
> +}
> +
> +static acpi_status acpi_i2c_add_device(acpi_handle handle, u32 level,
> +				       void *data, void **return_value)
> +{
> +	struct i2c_adapter *adapter = data;
> +	struct list_head resource_list;
> +	struct i2c_board_info info;
> +	struct acpi_device *adev;
> +	int ret;
> +
> +	if (acpi_bus_get_device(handle, &adev))
> +		return AE_OK;
> +	if (acpi_bus_get_status(adev) || !adev->status.present)
> +		return AE_OK;
> +
> +	memset(&info, 0, sizeof(info));
> +	info.acpi_node.companion = adev;
> +	info.irq = -1;
> +
> +	INIT_LIST_HEAD(&resource_list);
> +	ret = acpi_dev_get_resources(adev, &resource_list,
> +				     acpi_i2c_add_resource, &info);
> +	acpi_dev_free_resource_list(&resource_list);
> +
> +	if (ret < 0 || !info.addr)
> +		return AE_OK;
> +
> +	adev->power.flags.ignore_parent = true;
> +	strlcpy(info.type, dev_name(&adev->dev), sizeof(info.type));
> +	if (!i2c_new_device(adapter, &info)) {
> +		adev->power.flags.ignore_parent = false;
> +		dev_err(&adapter->dev,
> +			"failed to add I2C device %s from ACPI\n",
> +			dev_name(&adev->dev));
> +	}
> +
> +	return AE_OK;
> +}
> +
> +/**
> + * acpi_i2c_register_devices - enumerate I2C slave devices behind adapter
> + * @adap: pointer to adapter
> + *
> + * Enumerate all I2C slave devices behind this adapter by walking the ACPI
> + * namespace. When a device is found it will be added to the Linux device
> + * model and bound to the corresponding ACPI handle.
> + */
> +void acpi_i2c_register_devices(struct i2c_adapter *adap)
> +{
> +	acpi_handle handle;
> +	acpi_status status;
> +
> +	if (!adap->dev.parent)
> +		return;
> +
> +	handle = ACPI_HANDLE(adap->dev.parent);
> +	if (!handle)
> +		return;
> +
> +	status = acpi_walk_namespace(ACPI_TYPE_DEVICE, handle, 1,
> +				     acpi_i2c_add_device, NULL,
> +				     adap, NULL);
> +	if (ACPI_FAILURE(status))
> +		dev_warn(&adap->dev, "failed to enumerate I2C slaves\n");
> +}
> +
> +#ifdef CONFIG_ACPI_I2C_OPREGION
> +static int acpi_gsb_i2c_read_bytes(struct i2c_client *client,
> +		u8 cmd, u8 *data, u8 data_len)
> +{
> +
> +	struct i2c_msg msgs[2];
> +	int ret;
> +	u8 *buffer;
> +
> +	buffer = kzalloc(data_len, GFP_KERNEL);
> +	if (!buffer)
> +		return AE_NO_MEMORY;
> +
> +	msgs[0].addr = client->addr;
> +	msgs[0].flags = client->flags;
> +	msgs[0].len = 1;
> +	msgs[0].buf = &cmd;
> +
> +	msgs[1].addr = client->addr;
> +	msgs[1].flags = client->flags | I2C_M_RD;
> +	msgs[1].len = data_len;
> +	msgs[1].buf = buffer;
> +
> +	ret = i2c_transfer(client->adapter, msgs, ARRAY_SIZE(msgs));
> +	if (ret < 0)
> +		dev_err(&client->adapter->dev, "i2c read failed\n");
> +	else
> +		memcpy(data, buffer, data_len);
> +
> +	kfree(buffer);
> +	return ret;
> +}
> +
> +static int acpi_gsb_i2c_write_bytes(struct i2c_client *client,
> +		u8 cmd, u8 *data, u8 data_len)
> +{
> +
> +	struct i2c_msg msgs[1];
> +	u8 *buffer;
> +	int ret = AE_OK;
> +
> +	buffer = kzalloc(data_len + 1, GFP_KERNEL);
> +	if (!buffer)
> +		return AE_NO_MEMORY;
> +
> +	buffer[0] = cmd;
> +	memcpy(buffer + 1, data, data_len);
> +
> +	msgs[0].addr = client->addr;
> +	msgs[0].flags = client->flags;
> +	msgs[0].len = data_len + 1;
> +	msgs[0].buf = buffer;
> +
> +	ret = i2c_transfer(client->adapter, msgs, ARRAY_SIZE(msgs));
> +	if (ret < 0)
> +		dev_err(&client->adapter->dev, "i2c write failed\n");
> +
> +	kfree(buffer);
> +	return ret;
> +}
> +
> +static acpi_status
> +acpi_i2c_space_handler(u32 function, acpi_physical_address command,
> +			u32 bits, u64 *value64,
> +			void *handler_context, void *region_context)
> +{
> +	struct gsb_buffer *gsb = (struct gsb_buffer *)value64;
> +	struct acpi_i2c_handler_data *data = handler_context;
> +	struct acpi_connection_info *info = &data->info;
> +	struct acpi_resource_i2c_serialbus *sb;
> +	struct i2c_adapter *adapter = data->adapter;
> +	struct i2c_client client;
> +	struct acpi_resource *ares;
> +	u32 accessor_type = function >> 16;
> +	u8 action = function & ACPI_IO_MASK;
> +	acpi_status ret = AE_OK;
> +	int status;
> +
> +	ret = acpi_buffer_to_resource(info->connection, info->length, &ares);
> +	if (ACPI_FAILURE(ret))
> +		return ret;
> +
> +	if (!value64 || ares->type != ACPI_RESOURCE_TYPE_SERIAL_BUS) {
> +		ret = AE_BAD_PARAMETER;
> +		goto err;
> +	}
> +
> +	sb = &ares->data.i2c_serial_bus;
> +	if (sb->type != ACPI_RESOURCE_SERIAL_TYPE_I2C) {
> +		ret = AE_BAD_PARAMETER;
> +		goto err;
> +	}
> +
> +	memset(&client, 0, sizeof(client));
> +	client.adapter = adapter;
> +	client.addr = sb->slave_address;
> +	client.flags = 0;
> +
> +	if (sb->access_mode == ACPI_I2C_10BIT_MODE)
> +		client.flags |= I2C_CLIENT_TEN;
> +
> +	switch (accessor_type) {
> +	case ACPI_GSB_ACCESS_ATTRIB_SEND_RCV:
> +		if (action == ACPI_READ) {
> +			status = i2c_smbus_read_byte(&client);
> +			if (status >= 0) {
> +				gsb->bdata = status;
> +				status = 0;
> +			}
> +		} else {
> +			status = i2c_smbus_write_byte(&client, gsb->bdata);
> +		}
> +		break;
> +
> +	case ACPI_GSB_ACCESS_ATTRIB_BYTE:
> +		if (action == ACPI_READ) {
> +			status = i2c_smbus_read_byte_data(&client, command);
> +			if (status >= 0) {
> +				gsb->bdata = status;
> +				status = 0;
> +			}
> +		} else {
> +			status = i2c_smbus_write_byte_data(&client, command,
> +					gsb->bdata);
> +		}
> +		break;
> +
> +	case ACPI_GSB_ACCESS_ATTRIB_WORD:
> +		if (action == ACPI_READ) {
> +			status = i2c_smbus_read_word_data(&client, command);
> +			if (status >= 0) {
> +				gsb->wdata = status;
> +				status = 0;
> +			}
> +		} else {
> +			status = i2c_smbus_write_word_data(&client, command,
> +					gsb->wdata);
> +		}
> +		break;
> +
> +	case ACPI_GSB_ACCESS_ATTRIB_BLOCK:
> +		if (action == ACPI_READ) {
> +			status = i2c_smbus_read_block_data(&client, command,
> +					gsb->data);
> +			if (status >= 0) {
> +				gsb->len = status;
> +				status = 0;
> +			}
> +		} else {
> +			status = i2c_smbus_write_block_data(&client, command,
> +					gsb->len, gsb->data);
> +		}
> +		break;
> +
> +	case ACPI_GSB_ACCESS_ATTRIB_MULTIBYTE:
> +		if (action == ACPI_READ) {
> +			status = acpi_gsb_i2c_read_bytes(&client, command,
> +					gsb->data, info->access_length);
> +			if (status > 0)
> +				status = 0;
> +		} else {
> +			status = acpi_gsb_i2c_write_bytes(&client, command,
> +					gsb->data, info->access_length);
> +		}
> +		break;
> +
> +	default:
> +		pr_info("protocol(0x%02x) is not supported.\n", accessor_type);
> +		ret = AE_BAD_PARAMETER;
> +		goto err;
> +	}
> +
> +	gsb->status = status;
> +
> + err:
> +	ACPI_FREE(ares);
> +	return ret;
> +}
> +
> +
> +int acpi_i2c_install_space_handler(struct i2c_adapter *adapter)
> +{
> +	acpi_handle handle = ACPI_HANDLE(adapter->dev.parent);
> +	struct acpi_i2c_handler_data *data;
> +	acpi_status status;
> +
> +	if (!handle)
> +		return -ENODEV;
> +
> +	data = kzalloc(sizeof(struct acpi_i2c_handler_data),
> +			    GFP_KERNEL);
> +	if (!data)
> +		return -ENOMEM;
> +
> +	data->adapter = adapter;
> +	status = acpi_bus_attach_private_data(handle, (void *)data);
> +	if (ACPI_FAILURE(status)) {
> +		kfree(data);
> +		return -ENOMEM;
> +	}
> +
> +	status = acpi_install_address_space_handler(handle,
> +				ACPI_ADR_SPACE_GSBUS,
> +				&acpi_i2c_space_handler,
> +				NULL,
> +				data);
> +	if (ACPI_FAILURE(status)) {
> +		dev_err(&adapter->dev, "Error installing i2c space handler\n");
> +		acpi_bus_detach_private_data(handle);
> +		kfree(data);
> +		return -ENOMEM;
> +	}
> +
> +	return 0;
> +}
> +
> +void acpi_i2c_remove_space_handler(struct i2c_adapter *adapter)
> +{
> +	acpi_handle handle = ACPI_HANDLE(adapter->dev.parent);
> +	struct acpi_i2c_handler_data *data;
> +	acpi_status status;
> +
> +	if (!handle)
> +		return;
> +
> +	acpi_remove_address_space_handler(handle,
> +				ACPI_ADR_SPACE_GSBUS,
> +				&acpi_i2c_space_handler);
> +
> +	status = acpi_bus_get_private_data(handle, (void **)&data);
> +	if (ACPI_SUCCESS(status))
> +		kfree(data);
> +
> +	acpi_bus_detach_private_data(handle);
> +}
> +#endif
> +#endif /* CONFIG_ACPI */
> +
>  /* ------------------------------------------------------------------------- */
>  
>  static const struct i2c_device_id *i2c_match_id(const struct i2c_device_id *id,
> 


-- 
Best regards
Tianyu Lan

Re: [PATCH] i2c: move acpi code back into the core

[Wolfram Sang]

[-- Attachment #1: Type: text/plain, Size: 172 bytes --]


> Sorry for later response due to sickness. I can't write this patch in
> time. Sorry again. I will test it soon.

Oh, get well soon! Please say so next time, so I know.


[-- Attachment #2: Digital signature --]
[-- Type: application/pgp-signature, Size: 819 bytes --]

Re: [PATCH] i2c: move acpi code back into the core

[Wolfram Sang]

[-- Attachment #1: Type: text/plain, Size: 172 bytes --]


> Sorry for later response due to sickness. I can't write this patch in
> time. Sorry again. I will test it soon.

Oh, get well soon! Please say so next time, so I know.


[-- Attachment #2: Digital signature --]
[-- Type: application/pgp-signature, Size: 819 bytes --]

Re: [PATCH] i2c: move acpi code back into the core

[Lan Tianyu]

On 2014年09月23日 13:39, Wolfram Sang wrote:
> 
>> Sorry for later response due to sickness. I can't write this patch in
>> time. Sorry again. I will test it soon.
> 
> Oh, get well soon! Please say so next time, so I know.
> 

Thanks. OK.
I have put the patch into test system and need to wait some time.

-- 
Best regards
Tianyu Lan

Re: [PATCH] i2c: move acpi code back into the core

[Lan Tianyu]

On 2014年09月23日 13:39, Wolfram Sang wrote:
> 
>> Sorry for later response due to sickness. I can't write this patch in
>> time. Sorry again. I will test it soon.
> 
> Oh, get well soon! Please say so next time, so I know.
> 

Thanks. OK.
I have put the patch into test system and need to wait some time.

-- 
Best regards
Tianyu Lan

Re: [PATCH] i2c: move acpi code back into the core

[Lan Tianyu]

On 2014年09月23日 15:09, Lan Tianyu wrote:
> On 2014年09月23日 13:39, Wolfram Sang wrote:
>>
>>> Sorry for later response due to sickness. I can't write this patch in
>>> time. Sorry again. I will test it soon.
>>
>> Oh, get well soon! Please say so next time, so I know.
>>
> 
> Thanks. OK.
> I have put the patch into test system and need to wait some time.
> 

Hi Wolfram:
The patch passed through the following 110 configure build test in the
0-day build test system.


configs tested: 110

mips                             allmodconfig
mips                                   jz4740
mips                              allnoconfig
mips                      fuloong2e_defconfig
mips                                     txx9
x86_64                            allnoconfig
sh                            titan_defconfig
sh                          rsk7269_defconfig
sh                  sh7785lcr_32bit_defconfig
sh                                allnoconfig
x86_64                     randconfig-c3-0923
x86_64                     randconfig-c1-0923
x86_64                     randconfig-c2-0923
x86_64                     randconfig-c0-0923
arm                       omap2plus_defconfig
arm                                    sa1100
arm                              allmodconfig
arm                          prima2_defconfig
arm                         at91_dt_defconfig
arm                               allnoconfig
arm                                   samsung
arm                       spear13xx_defconfig
arm                         s3c2410_defconfig
arm                                  iop-adma
arm                       imx_v6_v7_defconfig
arm                                       mmp
arm                           tegra_defconfig
arm                                      arm5
arm                          marzen_defconfig
arm                                  at_hdmac
arm                                    ep93xx
arm                                        sh
arm                                     arm67
parisc                        c3000_defconfig
parisc                         b180_defconfig
parisc                              defconfig
alpha                               defconfig
parisc                            allnoconfig
powerpc                  iss476-smp_defconfig
powerpc                 mpc8315_rdb_defconfig
mips                          ath79_defconfig
arm                             bcm_defconfig
powerpc                   gef_ppc9a_defconfig
i386                      randconfig-ha0-0923
i386                      randconfig-ha1-0923
i386                      randconfig-ha2-0923
i386                      randconfig-ha3-0923
ia64                             allmodconfig
ia64                              allnoconfig
ia64                                defconfig
ia64                             alldefconfig
microblaze                      mmu_defconfig
microblaze                    nommu_defconfig
microblaze                       allyesconfig
s390                             allmodconfig
s390                              allnoconfig
s390                                defconfig
x86_64                    randconfig-ha1-0923
x86_64                    randconfig-ha3-0923
x86_64                    randconfig-ha0-0923
x86_64                    randconfig-ha2-0923
xtensa                       common_defconfig
m32r                       m32104ut_defconfig
xtensa                          iss_defconfig
m32r                         opsput_defconfig
m32r                           usrv_defconfig
m32r                     mappi3.smp_defconfig
sparc                               defconfig
sparc64                           allnoconfig
sparc64                             defconfig
i386                             allyesconfig
cris                 etrax-100lx_v2_defconfig
blackfin                  TCM-BF537_defconfig
blackfin            BF561-EZKIT-SMP_defconfig
blackfin                BF533-EZKIT_defconfig
blackfin                BF526-EZBRD_defconfig
i386                       randconfig-r0-0923
i386                       randconfig-r2-0923
i386                       randconfig-r3-0923
i386                       randconfig-r1-0923
x86_64                 randconfig-s0-09231616
x86_64                 randconfig
Hi Wolfram:
	The patch passed through the following 110 configure build test in the
0-day build test system.-s1-09231616
x86_64                           allmodconfig
i386                             alldefconfig
i386                             allmodconfig
i386                              allnoconfig
i386                                defconfig
i386                     randconfig-x009-0922
x86_64                   randconfig-x003-0922
x86_64                   randconfig-x004-0922
i386                     randconfig-x006-0922
x86_64                   randconfig-x001-0922
i386                     randconfig-x005-0922
x86_64                   randconfig-x006-0922
i386                     randconfig-x001-0922
i386                     randconfig-x004-0922
i386                     randconfig-x003-0922
i386                     randconfig-x000-0922
x86_64                   randconfig-x002-0922
x86_64                   randconfig-x008-0922
i386                     randconfig-x008-0922
i386                     randconfig-x007-0922
x86_64                   randconfig-x009-0922
x86_64                   randconfig-x000-0922
x86_64                   randconfig-x007-0922
i386                     randconfig-x002-0922
x86_64                   randconfig-x005-0922
x86_64                             acpi-redef
x86_64                           allyesdebian
x86_64                                nfsroot


-- 
Best regards
Tianyu Lan

Re: [PATCH] i2c: move acpi code back into the core

[Wolfram Sang]

[-- Attachment #1: Type: text/plain, Size: 244 bytes --]

> Hi Wolfram:
> The patch passed through the following 110 configure build test in the
> 0-day build test system.

Thanks, but my tree gets checked automatically anyhow. What I'd need is
functional tests because I don't have hardware to test.


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Re: [PATCH] i2c: move acpi code back into the core

[Mika Westerberg]

On Mon, Sep 22, 2014 at 11:06:46PM +0200, Wolfram Sang wrote:
> Commit 5d98e61d337c ("I2C/ACPI: Add i2c ACPI operation region support") renamed
> the i2c-core module. This may cause regressions for distributions, so put the
> ACPI code back into the core. No code was changed.

Thanks Wolfram for doing this!

I tested this already and it of course works but there are few things
that you are missing so this probably needs an additional iteration.

> Reported-by: Jean Delvare <jdelvare-l3A5Bk7waGM@public.gmane.org>
> Signed-off-by: Wolfram Sang <wsa-z923LK4zBo2bacvFa/9K2g@public.gmane.org>
> Cc: Mika Westerberg <mika.westerberg-VuQAYsv1563Yd54FQh9/CA@public.gmane.org>
> Cc: Lan Tianyu <tianyu.lan-ral2JQCrhuEAvxtiuMwx3w@public.gmane.org>
> Cc: Jean Delvare <jdelvare-l3A5Bk7waGM@public.gmane.org>
> ---
> 
> Lan Tianyi, this is a patch I expected to get from you, fully tested. Since we
> are approaching the final release soon, I did it now. Please do test this
> patch. All I can do is build test (it works for me, build robots are still
> running). If nobody tests this, I have to revert the ACPI changes of this
> cycle.
> 
> Jean, can you have a look, too?
> 
> We can think of something better for the next release, but for now, this should be it.
> 
>  MAINTAINERS            |   1 -
>  drivers/i2c/Makefile   |   5 +-
>  drivers/i2c/i2c-acpi.c | 364 -------------------------------------------------
>  drivers/i2c/i2c-core.c | 345 ++++++++++++++++++++++++++++++++++++++++++++++
>  4 files changed, 346 insertions(+), 369 deletions(-)
>  delete mode 100644 drivers/i2c/i2c-acpi.c
> 
> diff --git a/MAINTAINERS b/MAINTAINERS
> index 809ecd680d88..e3682d0dea1e 100644
> --- a/MAINTAINERS
> +++ b/MAINTAINERS
> @@ -4477,7 +4477,6 @@ M:	Mika Westerberg <mika.westerberg-VuQAYsv1563Yd54FQh9/CA@public.gmane.org>
>  L:	linux-i2c-u79uwXL29TY76Z2rM5mHXA@public.gmane.org
>  L:	linux-acpi-u79uwXL29TY76Z2rM5mHXA@public.gmane.org
>  S:	Maintained
> -F:	drivers/i2c/i2c-acpi.c

You can remove my name from MAINTANERS as well. I'm not I2C subsystem
maintainer :) Of course I will still assist reviewing ACPI related
changes in i2c-core.c.

>  I2C-TAOS-EVM DRIVER
>  M:	Jean Delvare <jdelvare-l3A5Bk7waGM@public.gmane.org>

...

> +/**
> + * acpi_i2c_register_devices - enumerate I2C slave devices behind adapter
> + * @adap: pointer to adapter
> + *
> + * Enumerate all I2C slave devices behind this adapter by walking the ACPI
> + * namespace. When a device is found it will be added to the Linux device
> + * model and bound to the corresponding ACPI handle.
> + */
> +void acpi_i2c_register_devices(struct i2c_adapter *adap)

static

> +{
> +	acpi_handle handle;
> +	acpi_status status;
> +
> +	if (!adap->dev.parent)
> +		return;
> +
> +	handle = ACPI_HANDLE(adap->dev.parent);
> +	if (!handle)
> +		return;
> +
> +	status = acpi_walk_namespace(ACPI_TYPE_DEVICE, handle, 1,
> +				     acpi_i2c_add_device, NULL,
> +				     adap, NULL);
> +	if (ACPI_FAILURE(status))
> +		dev_warn(&adap->dev, "failed to enumerate I2C slaves\n");
> +}
> +

...

> +int acpi_i2c_install_space_handler(struct i2c_adapter *adapter)

static

> +{
> +	acpi_handle handle = ACPI_HANDLE(adapter->dev.parent);
> +	struct acpi_i2c_handler_data *data;
> +	acpi_status status;
> +
> +	if (!handle)
> +		return -ENODEV;
> +
> +	data = kzalloc(sizeof(struct acpi_i2c_handler_data),
> +			    GFP_KERNEL);
> +	if (!data)
> +		return -ENOMEM;
> +
> +	data->adapter = adapter;
> +	status = acpi_bus_attach_private_data(handle, (void *)data);
> +	if (ACPI_FAILURE(status)) {
> +		kfree(data);
> +		return -ENOMEM;
> +	}
> +
> +	status = acpi_install_address_space_handler(handle,
> +				ACPI_ADR_SPACE_GSBUS,
> +				&acpi_i2c_space_handler,
> +				NULL,
> +				data);
> +	if (ACPI_FAILURE(status)) {
> +		dev_err(&adapter->dev, "Error installing i2c space handler\n");
> +		acpi_bus_detach_private_data(handle);
> +		kfree(data);
> +		return -ENOMEM;
> +	}
> +
> +	return 0;
> +}
> +
> +void acpi_i2c_remove_space_handler(struct i2c_adapter *adapter)

static

> +{
> +	acpi_handle handle = ACPI_HANDLE(adapter->dev.parent);
> +	struct acpi_i2c_handler_data *data;
> +	acpi_status status;
> +
> +	if (!handle)
> +		return;
> +
> +	acpi_remove_address_space_handler(handle,
> +				ACPI_ADR_SPACE_GSBUS,
> +				&acpi_i2c_space_handler);
> +
> +	status = acpi_bus_get_private_data(handle, (void **)&data);
> +	if (ACPI_SUCCESS(status))
> +		kfree(data);
> +
> +	acpi_bus_detach_private_data(handle);
> +}
> +#endif

I would put there

#endif /* CONFIG_ACPI_I2C_OPREGION */

> +#endif /* CONFIG_ACPI */

Also please remove all ACPI related stuff in include/linux/i2c.h. That
is not needed anymore.

Re: [PATCH] i2c: move acpi code back into the core

[Mika Westerberg]

On Mon, Sep 22, 2014 at 11:06:46PM +0200, Wolfram Sang wrote:
> Commit 5d98e61d337c ("I2C/ACPI: Add i2c ACPI operation region support") renamed
> the i2c-core module. This may cause regressions for distributions, so put the
> ACPI code back into the core. No code was changed.

Thanks Wolfram for doing this!

I tested this already and it of course works but there are few things
that you are missing so this probably needs an additional iteration.

> Reported-by: Jean Delvare <jdelvare@suse.de>
> Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
> Cc: Mika Westerberg <mika.westerberg@linux.intel.com>
> Cc: Lan Tianyu <tianyu.lan@intel.com>
> Cc: Jean Delvare <jdelvare@suse.de>
> ---
> 
> Lan Tianyi, this is a patch I expected to get from you, fully tested. Since we
> are approaching the final release soon, I did it now. Please do test this
> patch. All I can do is build test (it works for me, build robots are still
> running). If nobody tests this, I have to revert the ACPI changes of this
> cycle.
> 
> Jean, can you have a look, too?
> 
> We can think of something better for the next release, but for now, this should be it.
> 
>  MAINTAINERS            |   1 -
>  drivers/i2c/Makefile   |   5 +-
>  drivers/i2c/i2c-acpi.c | 364 -------------------------------------------------
>  drivers/i2c/i2c-core.c | 345 ++++++++++++++++++++++++++++++++++++++++++++++
>  4 files changed, 346 insertions(+), 369 deletions(-)
>  delete mode 100644 drivers/i2c/i2c-acpi.c
> 
> diff --git a/MAINTAINERS b/MAINTAINERS
> index 809ecd680d88..e3682d0dea1e 100644
> --- a/MAINTAINERS
> +++ b/MAINTAINERS
> @@ -4477,7 +4477,6 @@ M:	Mika Westerberg <mika.westerberg@linux.intel.com>
>  L:	linux-i2c@vger.kernel.org
>  L:	linux-acpi@vger.kernel.org
>  S:	Maintained
> -F:	drivers/i2c/i2c-acpi.c

You can remove my name from MAINTANERS as well. I'm not I2C subsystem
maintainer :) Of course I will still assist reviewing ACPI related
changes in i2c-core.c.

>  I2C-TAOS-EVM DRIVER
>  M:	Jean Delvare <jdelvare@suse.de>

...

> +/**
> + * acpi_i2c_register_devices - enumerate I2C slave devices behind adapter
> + * @adap: pointer to adapter
> + *
> + * Enumerate all I2C slave devices behind this adapter by walking the ACPI
> + * namespace. When a device is found it will be added to the Linux device
> + * model and bound to the corresponding ACPI handle.
> + */
> +void acpi_i2c_register_devices(struct i2c_adapter *adap)

static

> +{
> +	acpi_handle handle;
> +	acpi_status status;
> +
> +	if (!adap->dev.parent)
> +		return;
> +
> +	handle = ACPI_HANDLE(adap->dev.parent);
> +	if (!handle)
> +		return;
> +
> +	status = acpi_walk_namespace(ACPI_TYPE_DEVICE, handle, 1,
> +				     acpi_i2c_add_device, NULL,
> +				     adap, NULL);
> +	if (ACPI_FAILURE(status))
> +		dev_warn(&adap->dev, "failed to enumerate I2C slaves\n");
> +}
> +

...

> +int acpi_i2c_install_space_handler(struct i2c_adapter *adapter)

static

> +{
> +	acpi_handle handle = ACPI_HANDLE(adapter->dev.parent);
> +	struct acpi_i2c_handler_data *data;
> +	acpi_status status;
> +
> +	if (!handle)
> +		return -ENODEV;
> +
> +	data = kzalloc(sizeof(struct acpi_i2c_handler_data),
> +			    GFP_KERNEL);
> +	if (!data)
> +		return -ENOMEM;
> +
> +	data->adapter = adapter;
> +	status = acpi_bus_attach_private_data(handle, (void *)data);
> +	if (ACPI_FAILURE(status)) {
> +		kfree(data);
> +		return -ENOMEM;
> +	}
> +
> +	status = acpi_install_address_space_handler(handle,
> +				ACPI_ADR_SPACE_GSBUS,
> +				&acpi_i2c_space_handler,
> +				NULL,
> +				data);
> +	if (ACPI_FAILURE(status)) {
> +		dev_err(&adapter->dev, "Error installing i2c space handler\n");
> +		acpi_bus_detach_private_data(handle);
> +		kfree(data);
> +		return -ENOMEM;
> +	}
> +
> +	return 0;
> +}
> +
> +void acpi_i2c_remove_space_handler(struct i2c_adapter *adapter)

static

> +{
> +	acpi_handle handle = ACPI_HANDLE(adapter->dev.parent);
> +	struct acpi_i2c_handler_data *data;
> +	acpi_status status;
> +
> +	if (!handle)
> +		return;
> +
> +	acpi_remove_address_space_handler(handle,
> +				ACPI_ADR_SPACE_GSBUS,
> +				&acpi_i2c_space_handler);
> +
> +	status = acpi_bus_get_private_data(handle, (void **)&data);
> +	if (ACPI_SUCCESS(status))
> +		kfree(data);
> +
> +	acpi_bus_detach_private_data(handle);
> +}
> +#endif

I would put there

#endif /* CONFIG_ACPI_I2C_OPREGION */

> +#endif /* CONFIG_ACPI */

Also please remove all ACPI related stuff in include/linux/i2c.h. That
is not needed anymore.

Re: [PATCH] i2c: move acpi code back into the core

[Wolfram Sang]

[-- Attachment #1: Type: text/plain, Size: 968 bytes --]

> > diff --git a/MAINTAINERS b/MAINTAINERS
> > index 809ecd680d88..e3682d0dea1e 100644
> > --- a/MAINTAINERS
> > +++ b/MAINTAINERS
> > @@ -4477,7 +4477,6 @@ M:	Mika Westerberg <mika.westerberg@linux.intel.com>
> >  L:	linux-i2c@vger.kernel.org
> >  L:	linux-acpi@vger.kernel.org
> >  S:	Maintained
> > -F:	drivers/i2c/i2c-acpi.c
> 
> You can remove my name from MAINTANERS as well. I'm not I2C subsystem
> maintainer :) Of course I will still assist reviewing ACPI related
> changes in i2c-core.c.

I'd like to keep this since the header says I2C/ACPI. I am thinking of
adding something like 'K: i2c_.*acpi_' but that can wait. For now, we
need a working solution _very_ soon.

> > +#endif
> 
> I would put there
> 
> #endif /* CONFIG_ACPI_I2C_OPREGION */

I didn't want to change lines not written by me, but well yeah...

> Also please remove all ACPI related stuff in include/linux/i2c.h. That
> is not needed anymore.

Yup, thanks!


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[PATCH] i2c: move acpi code back into the core

[Wolfram Sang]

Commit 5d98e61d337c ("I2C/ACPI: Add i2c ACPI operation region support")
renamed the i2c-core module. This may cause regressions for
distributions, so put the ACPI code back into the core.

Reported-by: Jean Delvare <jdelvare@suse.de>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
Cc: Mika Westerberg <mika.westerberg@linux.intel.com>
Cc: Lan Tianyu <tianyu.lan@intel.com>
---
 MAINTAINERS            |   1 -
 drivers/i2c/Makefile   |   5 +-
 drivers/i2c/i2c-acpi.c | 364 -------------------------------------------------
 drivers/i2c/i2c-core.c | 345 ++++++++++++++++++++++++++++++++++++++++++++++
 4 files changed, 346 insertions(+), 369 deletions(-)
 delete mode 100644 drivers/i2c/i2c-acpi.c

diff --git a/MAINTAINERS b/MAINTAINERS
index 809ecd680d88..e3682d0dea1e 100644
--- a/MAINTAINERS
+++ b/MAINTAINERS
@@ -4477,7 +4477,6 @@ M:	Mika Westerberg <mika.westerberg@linux.intel.com>
 L:	linux-i2c@vger.kernel.org
 L:	linux-acpi@vger.kernel.org
 S:	Maintained
-F:	drivers/i2c/i2c-acpi.c
 
 I2C-TAOS-EVM DRIVER
 M:	Jean Delvare <jdelvare@suse.de>
diff --git a/drivers/i2c/Makefile b/drivers/i2c/Makefile
index e0228b228256..1722f50f2473 100644
--- a/drivers/i2c/Makefile
+++ b/drivers/i2c/Makefile
@@ -2,11 +2,8 @@
 # Makefile for the i2c core.
 #
 
-i2ccore-y := i2c-core.o
-i2ccore-$(CONFIG_ACPI)	 	+= i2c-acpi.o
-
 obj-$(CONFIG_I2C_BOARDINFO)	+= i2c-boardinfo.o
-obj-$(CONFIG_I2C)		+= i2ccore.o
+obj-$(CONFIG_I2C)		+= i2c-core.o
 obj-$(CONFIG_I2C_SMBUS)		+= i2c-smbus.o
 obj-$(CONFIG_I2C_CHARDEV)	+= i2c-dev.o
 obj-$(CONFIG_I2C_MUX)		+= i2c-mux.o
diff --git a/drivers/i2c/i2c-acpi.c b/drivers/i2c/i2c-acpi.c
deleted file mode 100644
index 0dbc18c15c43..000000000000
--- a/drivers/i2c/i2c-acpi.c
+++ /dev/null
@@ -1,364 +0,0 @@
-/*
- * I2C ACPI code
- *
- * Copyright (C) 2014 Intel Corp
- *
- * Author: Lan Tianyu <tianyu.lan@intel.com>
- *
- * This program is free software; you can redistribute it and/or modify
- * it under the terms of the GNU General Public License version 2 as
- * published by the Free Software Foundation.
- *
- * This program is distributed in the hope that it will be useful, but
- * WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY
- * or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
- * for more details.
- */
-#define pr_fmt(fmt) "I2C/ACPI : " fmt
-
-#include <linux/kernel.h>
-#include <linux/errno.h>
-#include <linux/err.h>
-#include <linux/i2c.h>
-#include <linux/acpi.h>
-
-struct acpi_i2c_handler_data {
-	struct acpi_connection_info info;
-	struct i2c_adapter *adapter;
-};
-
-struct gsb_buffer {
-	u8	status;
-	u8	len;
-	union {
-		u16	wdata;
-		u8	bdata;
-		u8	data[0];
-	};
-} __packed;
-
-static int acpi_i2c_add_resource(struct acpi_resource *ares, void *data)
-{
-	struct i2c_board_info *info = data;
-
-	if (ares->type == ACPI_RESOURCE_TYPE_SERIAL_BUS) {
-		struct acpi_resource_i2c_serialbus *sb;
-
-		sb = &ares->data.i2c_serial_bus;
-		if (sb->type == ACPI_RESOURCE_SERIAL_TYPE_I2C) {
-			info->addr = sb->slave_address;
-			if (sb->access_mode == ACPI_I2C_10BIT_MODE)
-				info->flags |= I2C_CLIENT_TEN;
-		}
-	} else if (info->irq < 0) {
-		struct resource r;
-
-		if (acpi_dev_resource_interrupt(ares, 0, &r))
-			info->irq = r.start;
-	}
-
-	/* Tell the ACPI core to skip this resource */
-	return 1;
-}
-
-static acpi_status acpi_i2c_add_device(acpi_handle handle, u32 level,
-				       void *data, void **return_value)
-{
-	struct i2c_adapter *adapter = data;
-	struct list_head resource_list;
-	struct i2c_board_info info;
-	struct acpi_device *adev;
-	int ret;
-
-	if (acpi_bus_get_device(handle, &adev))
-		return AE_OK;
-	if (acpi_bus_get_status(adev) || !adev->status.present)
-		return AE_OK;
-
-	memset(&info, 0, sizeof(info));
-	info.acpi_node.companion = adev;
-	info.irq = -1;
-
-	INIT_LIST_HEAD(&resource_list);
-	ret = acpi_dev_get_resources(adev, &resource_list,
-				     acpi_i2c_add_resource, &info);
-	acpi_dev_free_resource_list(&resource_list);
-
-	if (ret < 0 || !info.addr)
-		return AE_OK;
-
-	adev->power.flags.ignore_parent = true;
-	strlcpy(info.type, dev_name(&adev->dev), sizeof(info.type));
-	if (!i2c_new_device(adapter, &info)) {
-		adev->power.flags.ignore_parent = false;
-		dev_err(&adapter->dev,
-			"failed to add I2C device %s from ACPI\n",
-			dev_name(&adev->dev));
-	}
-
-	return AE_OK;
-}
-
-/**
- * acpi_i2c_register_devices - enumerate I2C slave devices behind adapter
- * @adap: pointer to adapter
- *
- * Enumerate all I2C slave devices behind this adapter by walking the ACPI
- * namespace. When a device is found it will be added to the Linux device
- * model and bound to the corresponding ACPI handle.
- */
-void acpi_i2c_register_devices(struct i2c_adapter *adap)
-{
-	acpi_handle handle;
-	acpi_status status;
-
-	if (!adap->dev.parent)
-		return;
-
-	handle = ACPI_HANDLE(adap->dev.parent);
-	if (!handle)
-		return;
-
-	status = acpi_walk_namespace(ACPI_TYPE_DEVICE, handle, 1,
-				     acpi_i2c_add_device, NULL,
-				     adap, NULL);
-	if (ACPI_FAILURE(status))
-		dev_warn(&adap->dev, "failed to enumerate I2C slaves\n");
-}
-
-#ifdef CONFIG_ACPI_I2C_OPREGION
-static int acpi_gsb_i2c_read_bytes(struct i2c_client *client,
-		u8 cmd, u8 *data, u8 data_len)
-{
-
-	struct i2c_msg msgs[2];
-	int ret;
-	u8 *buffer;
-
-	buffer = kzalloc(data_len, GFP_KERNEL);
-	if (!buffer)
-		return AE_NO_MEMORY;
-
-	msgs[0].addr = client->addr;
-	msgs[0].flags = client->flags;
-	msgs[0].len = 1;
-	msgs[0].buf = &cmd;
-
-	msgs[1].addr = client->addr;
-	msgs[1].flags = client->flags | I2C_M_RD;
-	msgs[1].len = data_len;
-	msgs[1].buf = buffer;
-
-	ret = i2c_transfer(client->adapter, msgs, ARRAY_SIZE(msgs));
-	if (ret < 0)
-		dev_err(&client->adapter->dev, "i2c read failed\n");
-	else
-		memcpy(data, buffer, data_len);
-
-	kfree(buffer);
-	return ret;
-}
-
-static int acpi_gsb_i2c_write_bytes(struct i2c_client *client,
-		u8 cmd, u8 *data, u8 data_len)
-{
-
-	struct i2c_msg msgs[1];
-	u8 *buffer;
-	int ret = AE_OK;
-
-	buffer = kzalloc(data_len + 1, GFP_KERNEL);
-	if (!buffer)
-		return AE_NO_MEMORY;
-
-	buffer[0] = cmd;
-	memcpy(buffer + 1, data, data_len);
-
-	msgs[0].addr = client->addr;
-	msgs[0].flags = client->flags;
-	msgs[0].len = data_len + 1;
-	msgs[0].buf = buffer;
-
-	ret = i2c_transfer(client->adapter, msgs, ARRAY_SIZE(msgs));
-	if (ret < 0)
-		dev_err(&client->adapter->dev, "i2c write failed\n");
-
-	kfree(buffer);
-	return ret;
-}
-
-static acpi_status
-acpi_i2c_space_handler(u32 function, acpi_physical_address command,
-			u32 bits, u64 *value64,
-			void *handler_context, void *region_context)
-{
-	struct gsb_buffer *gsb = (struct gsb_buffer *)value64;
-	struct acpi_i2c_handler_data *data = handler_context;
-	struct acpi_connection_info *info = &data->info;
-	struct acpi_resource_i2c_serialbus *sb;
-	struct i2c_adapter *adapter = data->adapter;
-	struct i2c_client client;
-	struct acpi_resource *ares;
-	u32 accessor_type = function >> 16;
-	u8 action = function & ACPI_IO_MASK;
-	acpi_status ret = AE_OK;
-	int status;
-
-	ret = acpi_buffer_to_resource(info->connection, info->length, &ares);
-	if (ACPI_FAILURE(ret))
-		return ret;
-
-	if (!value64 || ares->type != ACPI_RESOURCE_TYPE_SERIAL_BUS) {
-		ret = AE_BAD_PARAMETER;
-		goto err;
-	}
-
-	sb = &ares->data.i2c_serial_bus;
-	if (sb->type != ACPI_RESOURCE_SERIAL_TYPE_I2C) {
-		ret = AE_BAD_PARAMETER;
-		goto err;
-	}
-
-	memset(&client, 0, sizeof(client));
-	client.adapter = adapter;
-	client.addr = sb->slave_address;
-	client.flags = 0;
-
-	if (sb->access_mode == ACPI_I2C_10BIT_MODE)
-		client.flags |= I2C_CLIENT_TEN;
-
-	switch (accessor_type) {
-	case ACPI_GSB_ACCESS_ATTRIB_SEND_RCV:
-		if (action == ACPI_READ) {
-			status = i2c_smbus_read_byte(&client);
-			if (status >= 0) {
-				gsb->bdata = status;
-				status = 0;
-			}
-		} else {
-			status = i2c_smbus_write_byte(&client, gsb->bdata);
-		}
-		break;
-
-	case ACPI_GSB_ACCESS_ATTRIB_BYTE:
-		if (action == ACPI_READ) {
-			status = i2c_smbus_read_byte_data(&client, command);
-			if (status >= 0) {
-				gsb->bdata = status;
-				status = 0;
-			}
-		} else {
-			status = i2c_smbus_write_byte_data(&client, command,
-					gsb->bdata);
-		}
-		break;
-
-	case ACPI_GSB_ACCESS_ATTRIB_WORD:
-		if (action == ACPI_READ) {
-			status = i2c_smbus_read_word_data(&client, command);
-			if (status >= 0) {
-				gsb->wdata = status;
-				status = 0;
-			}
-		} else {
-			status = i2c_smbus_write_word_data(&client, command,
-					gsb->wdata);
-		}
-		break;
-
-	case ACPI_GSB_ACCESS_ATTRIB_BLOCK:
-		if (action == ACPI_READ) {
-			status = i2c_smbus_read_block_data(&client, command,
-					gsb->data);
-			if (status >= 0) {
-				gsb->len = status;
-				status = 0;
-			}
-		} else {
-			status = i2c_smbus_write_block_data(&client, command,
-					gsb->len, gsb->data);
-		}
-		break;
-
-	case ACPI_GSB_ACCESS_ATTRIB_MULTIBYTE:
-		if (action == ACPI_READ) {
-			status = acpi_gsb_i2c_read_bytes(&client, command,
-					gsb->data, info->access_length);
-			if (status > 0)
-				status = 0;
-		} else {
-			status = acpi_gsb_i2c_write_bytes(&client, command,
-					gsb->data, info->access_length);
-		}
-		break;
-
-	default:
-		pr_info("protocol(0x%02x) is not supported.\n", accessor_type);
-		ret = AE_BAD_PARAMETER;
-		goto err;
-	}
-
-	gsb->status = status;
-
- err:
-	ACPI_FREE(ares);
-	return ret;
-}
-
-
-int acpi_i2c_install_space_handler(struct i2c_adapter *adapter)
-{
-	acpi_handle handle = ACPI_HANDLE(adapter->dev.parent);
-	struct acpi_i2c_handler_data *data;
-	acpi_status status;
-
-	if (!handle)
-		return -ENODEV;
-
-	data = kzalloc(sizeof(struct acpi_i2c_handler_data),
-			    GFP_KERNEL);
-	if (!data)
-		return -ENOMEM;
-
-	data->adapter = adapter;
-	status = acpi_bus_attach_private_data(handle, (void *)data);
-	if (ACPI_FAILURE(status)) {
-		kfree(data);
-		return -ENOMEM;
-	}
-
-	status = acpi_install_address_space_handler(handle,
-				ACPI_ADR_SPACE_GSBUS,
-				&acpi_i2c_space_handler,
-				NULL,
-				data);
-	if (ACPI_FAILURE(status)) {
-		dev_err(&adapter->dev, "Error installing i2c space handler\n");
-		acpi_bus_detach_private_data(handle);
-		kfree(data);
-		return -ENOMEM;
-	}
-
-	return 0;
-}
-
-void acpi_i2c_remove_space_handler(struct i2c_adapter *adapter)
-{
-	acpi_handle handle = ACPI_HANDLE(adapter->dev.parent);
-	struct acpi_i2c_handler_data *data;
-	acpi_status status;
-
-	if (!handle)
-		return;
-
-	acpi_remove_address_space_handler(handle,
-				ACPI_ADR_SPACE_GSBUS,
-				&acpi_i2c_space_handler);
-
-	status = acpi_bus_get_private_data(handle, (void **)&data);
-	if (ACPI_SUCCESS(status))
-		kfree(data);
-
-	acpi_bus_detach_private_data(handle);
-}
-#endif
diff --git a/drivers/i2c/i2c-core.c b/drivers/i2c/i2c-core.c
index 632057a44615..3fbd5d5c38bf 100644
--- a/drivers/i2c/i2c-core.c
+++ b/drivers/i2c/i2c-core.c
@@ -27,6 +27,8 @@
    OF support is copyright (c) 2008 Jochen Friedrich <jochen@scram.de>
    (based on a previous patch from Jon Smirl <jonsmirl@gmail.com>) and
    (c) 2013  Wolfram Sang <wsa@the-dreams.de>
+   I2C ACPI code Copyright (C) 2014 Intel Corp
+   Author: Lan Tianyu <tianyu.lan@intel.com>
  */
 
 #include <linux/module.h>
@@ -78,6 +80,349 @@ void i2c_transfer_trace_unreg(void)
 	static_key_slow_dec(&i2c_trace_msg);
 }
 
+#if defined(CONFIG_ACPI)
+struct acpi_i2c_handler_data {
+	struct acpi_connection_info info;
+	struct i2c_adapter *adapter;
+};
+
+struct gsb_buffer {
+	u8	status;
+	u8	len;
+	union {
+		u16	wdata;
+		u8	bdata;
+		u8	data[0];
+	};
+} __packed;
+
+static int acpi_i2c_add_resource(struct acpi_resource *ares, void *data)
+{
+	struct i2c_board_info *info = data;
+
+	if (ares->type == ACPI_RESOURCE_TYPE_SERIAL_BUS) {
+		struct acpi_resource_i2c_serialbus *sb;
+
+		sb = &ares->data.i2c_serial_bus;
+		if (sb->type == ACPI_RESOURCE_SERIAL_TYPE_I2C) {
+			info->addr = sb->slave_address;
+			if (sb->access_mode == ACPI_I2C_10BIT_MODE)
+				info->flags |= I2C_CLIENT_TEN;
+		}
+	} else if (info->irq < 0) {
+		struct resource r;
+
+		if (acpi_dev_resource_interrupt(ares, 0, &r))
+			info->irq = r.start;
+	}
+
+	/* Tell the ACPI core to skip this resource */
+	return 1;
+}
+
+static acpi_status acpi_i2c_add_device(acpi_handle handle, u32 level,
+				       void *data, void **return_value)
+{
+	struct i2c_adapter *adapter = data;
+	struct list_head resource_list;
+	struct i2c_board_info info;
+	struct acpi_device *adev;
+	int ret;
+
+	if (acpi_bus_get_device(handle, &adev))
+		return AE_OK;
+	if (acpi_bus_get_status(adev) || !adev->status.present)
+		return AE_OK;
+
+	memset(&info, 0, sizeof(info));
+	info.acpi_node.companion = adev;
+	info.irq = -1;
+
+	INIT_LIST_HEAD(&resource_list);
+	ret = acpi_dev_get_resources(adev, &resource_list,
+				     acpi_i2c_add_resource, &info);
+	acpi_dev_free_resource_list(&resource_list);
+
+	if (ret < 0 || !info.addr)
+		return AE_OK;
+
+	adev->power.flags.ignore_parent = true;
+	strlcpy(info.type, dev_name(&adev->dev), sizeof(info.type));
+	if (!i2c_new_device(adapter, &info)) {
+		adev->power.flags.ignore_parent = false;
+		dev_err(&adapter->dev,
+			"failed to add I2C device %s from ACPI\n",
+			dev_name(&adev->dev));
+	}
+
+	return AE_OK;
+}
+
+/**
+ * acpi_i2c_register_devices - enumerate I2C slave devices behind adapter
+ * @adap: pointer to adapter
+ *
+ * Enumerate all I2C slave devices behind this adapter by walking the ACPI
+ * namespace. When a device is found it will be added to the Linux device
+ * model and bound to the corresponding ACPI handle.
+ */
+void acpi_i2c_register_devices(struct i2c_adapter *adap)
+{
+	acpi_handle handle;
+	acpi_status status;
+
+	if (!adap->dev.parent)
+		return;
+
+	handle = ACPI_HANDLE(adap->dev.parent);
+	if (!handle)
+		return;
+
+	status = acpi_walk_namespace(ACPI_TYPE_DEVICE, handle, 1,
+				     acpi_i2c_add_device, NULL,
+				     adap, NULL);
+	if (ACPI_FAILURE(status))
+		dev_warn(&adap->dev, "failed to enumerate I2C slaves\n");
+}
+
+#ifdef CONFIG_ACPI_I2C_OPREGION
+static int acpi_gsb_i2c_read_bytes(struct i2c_client *client,
+		u8 cmd, u8 *data, u8 data_len)
+{
+
+	struct i2c_msg msgs[2];
+	int ret;
+	u8 *buffer;
+
+	buffer = kzalloc(data_len, GFP_KERNEL);
+	if (!buffer)
+		return AE_NO_MEMORY;
+
+	msgs[0].addr = client->addr;
+	msgs[0].flags = client->flags;
+	msgs[0].len = 1;
+	msgs[0].buf = &cmd;
+
+	msgs[1].addr = client->addr;
+	msgs[1].flags = client->flags | I2C_M_RD;
+	msgs[1].len = data_len;
+	msgs[1].buf = buffer;
+
+	ret = i2c_transfer(client->adapter, msgs, ARRAY_SIZE(msgs));
+	if (ret < 0)
+		dev_err(&client->adapter->dev, "i2c read failed\n");
+	else
+		memcpy(data, buffer, data_len);
+
+	kfree(buffer);
+	return ret;
+}
+
+static int acpi_gsb_i2c_write_bytes(struct i2c_client *client,
+		u8 cmd, u8 *data, u8 data_len)
+{
+
+	struct i2c_msg msgs[1];
+	u8 *buffer;
+	int ret = AE_OK;
+
+	buffer = kzalloc(data_len + 1, GFP_KERNEL);
+	if (!buffer)
+		return AE_NO_MEMORY;
+
+	buffer[0] = cmd;
+	memcpy(buffer + 1, data, data_len);
+
+	msgs[0].addr = client->addr;
+	msgs[0].flags = client->flags;
+	msgs[0].len = data_len + 1;
+	msgs[0].buf = buffer;
+
+	ret = i2c_transfer(client->adapter, msgs, ARRAY_SIZE(msgs));
+	if (ret < 0)
+		dev_err(&client->adapter->dev, "i2c write failed\n");
+
+	kfree(buffer);
+	return ret;
+}
+
+static acpi_status
+acpi_i2c_space_handler(u32 function, acpi_physical_address command,
+			u32 bits, u64 *value64,
+			void *handler_context, void *region_context)
+{
+	struct gsb_buffer *gsb = (struct gsb_buffer *)value64;
+	struct acpi_i2c_handler_data *data = handler_context;
+	struct acpi_connection_info *info = &data->info;
+	struct acpi_resource_i2c_serialbus *sb;
+	struct i2c_adapter *adapter = data->adapter;
+	struct i2c_client client;
+	struct acpi_resource *ares;
+	u32 accessor_type = function >> 16;
+	u8 action = function & ACPI_IO_MASK;
+	acpi_status ret = AE_OK;
+	int status;
+
+	ret = acpi_buffer_to_resource(info->connection, info->length, &ares);
+	if (ACPI_FAILURE(ret))
+		return ret;
+
+	if (!value64 || ares->type != ACPI_RESOURCE_TYPE_SERIAL_BUS) {
+		ret = AE_BAD_PARAMETER;
+		goto err;
+	}
+
+	sb = &ares->data.i2c_serial_bus;
+	if (sb->type != ACPI_RESOURCE_SERIAL_TYPE_I2C) {
+		ret = AE_BAD_PARAMETER;
+		goto err;
+	}
+
+	memset(&client, 0, sizeof(client));
+	client.adapter = adapter;
+	client.addr = sb->slave_address;
+	client.flags = 0;
+
+	if (sb->access_mode == ACPI_I2C_10BIT_MODE)
+		client.flags |= I2C_CLIENT_TEN;
+
+	switch (accessor_type) {
+	case ACPI_GSB_ACCESS_ATTRIB_SEND_RCV:
+		if (action == ACPI_READ) {
+			status = i2c_smbus_read_byte(&client);
+			if (status >= 0) {
+				gsb->bdata = status;
+				status = 0;
+			}
+		} else {
+			status = i2c_smbus_write_byte(&client, gsb->bdata);
+		}
+		break;
+
+	case ACPI_GSB_ACCESS_ATTRIB_BYTE:
+		if (action == ACPI_READ) {
+			status = i2c_smbus_read_byte_data(&client, command);
+			if (status >= 0) {
+				gsb->bdata = status;
+				status = 0;
+			}
+		} else {
+			status = i2c_smbus_write_byte_data(&client, command,
+					gsb->bdata);
+		}
+		break;
+
+	case ACPI_GSB_ACCESS_ATTRIB_WORD:
+		if (action == ACPI_READ) {
+			status = i2c_smbus_read_word_data(&client, command);
+			if (status >= 0) {
+				gsb->wdata = status;
+				status = 0;
+			}
+		} else {
+			status = i2c_smbus_write_word_data(&client, command,
+					gsb->wdata);
+		}
+		break;
+
+	case ACPI_GSB_ACCESS_ATTRIB_BLOCK:
+		if (action == ACPI_READ) {
+			status = i2c_smbus_read_block_data(&client, command,
+					gsb->data);
+			if (status >= 0) {
+				gsb->len = status;
+				status = 0;
+			}
+		} else {
+			status = i2c_smbus_write_block_data(&client, command,
+					gsb->len, gsb->data);
+		}
+		break;
+
+	case ACPI_GSB_ACCESS_ATTRIB_MULTIBYTE:
+		if (action == ACPI_READ) {
+			status = acpi_gsb_i2c_read_bytes(&client, command,
+					gsb->data, info->access_length);
+			if (status > 0)
+				status = 0;
+		} else {
+			status = acpi_gsb_i2c_write_bytes(&client, command,
+					gsb->data, info->access_length);
+		}
+		break;
+
+	default:
+		pr_info("protocol(0x%02x) is not supported.\n", accessor_type);
+		ret = AE_BAD_PARAMETER;
+		goto err;
+	}
+
+	gsb->status = status;
+
+ err:
+	ACPI_FREE(ares);
+	return ret;
+}
+
+
+int acpi_i2c_install_space_handler(struct i2c_adapter *adapter)
+{
+	acpi_handle handle = ACPI_HANDLE(adapter->dev.parent);
+	struct acpi_i2c_handler_data *data;
+	acpi_status status;
+
+	if (!handle)
+		return -ENODEV;
+
+	data = kzalloc(sizeof(struct acpi_i2c_handler_data),
+			    GFP_KERNEL);
+	if (!data)
+		return -ENOMEM;
+
+	data->adapter = adapter;
+	status = acpi_bus_attach_private_data(handle, (void *)data);
+	if (ACPI_FAILURE(status)) {
+		kfree(data);
+		return -ENOMEM;
+	}
+
+	status = acpi_install_address_space_handler(handle,
+				ACPI_ADR_SPACE_GSBUS,
+				&acpi_i2c_space_handler,
+				NULL,
+				data);
+	if (ACPI_FAILURE(status)) {
+		dev_err(&adapter->dev, "Error installing i2c space handler\n");
+		acpi_bus_detach_private_data(handle);
+		kfree(data);
+		return -ENOMEM;
+	}
+
+	return 0;
+}
+
+void acpi_i2c_remove_space_handler(struct i2c_adapter *adapter)
+{
+	acpi_handle handle = ACPI_HANDLE(adapter->dev.parent);
+	struct acpi_i2c_handler_data *data;
+	acpi_status status;
+
+	if (!handle)
+		return;
+
+	acpi_remove_address_space_handler(handle,
+				ACPI_ADR_SPACE_GSBUS,
+				&acpi_i2c_space_handler);
+
+	status = acpi_bus_get_private_data(handle, (void **)&data);
+	if (ACPI_SUCCESS(status))
+		kfree(data);
+
+	acpi_bus_detach_private_data(handle);
+}
+#endif
+#endif /* CONFIG_ACPI */
+
 /* ------------------------------------------------------------------------- */
 
 static const struct i2c_device_id *i2c_match_id(const struct i2c_device_id *id,
-- 
2.0.0