@@ -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>
@@ -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
deleted file mode 100644
@@ -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
@@ -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,
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