[Intel-gfx] [RFT 5/8] i2c: break out ACPI support into seperate file
Wolfram Sang
wsa at the-dreams.de
Sat May 27 16:40:15 UTC 2017
Removes some ifdeffery. Also add the new file to the relevant
MAINTAINERS section.
Signed-off-by: Wolfram Sang <wsa at the-dreams.de>
---
MAINTAINERS | 1 +
drivers/i2c/Makefile | 1 +
drivers/i2c/i2c-core-acpi.c | 653 ++++++++++++++++++++++++++++++++++++++++++++
drivers/i2c/i2c-core-base.c | 648 -------------------------------------------
drivers/i2c/i2c-core.h | 15 +
5 files changed, 670 insertions(+), 648 deletions(-)
create mode 100644 drivers/i2c/i2c-core-acpi.c
diff --git a/MAINTAINERS b/MAINTAINERS
index 9e984645c4b08b..3ce38e77f96e6b 100644
--- a/MAINTAINERS
+++ b/MAINTAINERS
@@ -6273,6 +6273,7 @@ M: Mika Westerberg <mika.westerberg at linux.intel.com>
L: linux-i2c at vger.kernel.org
L: linux-acpi at vger.kernel.org
S: Maintained
+F: drivers/i2c/i2c-core-acpi.c
I2C-TAOS-EVM DRIVER
M: Jean Delvare <jdelvare at suse.com>
diff --git a/drivers/i2c/Makefile b/drivers/i2c/Makefile
index 189e0e6476f0a6..7bb65a4369e1e1 100644
--- a/drivers/i2c/Makefile
+++ b/drivers/i2c/Makefile
@@ -5,6 +5,7 @@
obj-$(CONFIG_I2C_BOARDINFO) += i2c-boardinfo.o
obj-$(CONFIG_I2C) += i2c-core.o
i2c-core-objs := i2c-core-base.o i2c-core-smbus.o
+i2c-core-$(CONFIG_ACPI) += i2c-core-acpi.o
i2c-core-$(CONFIG_I2C_SLAVE) += i2c-core-slave.o
i2c-core-$(CONFIG_OF) += i2c-core-of.o
diff --git a/drivers/i2c/i2c-core-acpi.c b/drivers/i2c/i2c-core-acpi.c
new file mode 100644
index 00000000000000..052005579ed626
--- /dev/null
+++ b/drivers/i2c/i2c-core-acpi.c
@@ -0,0 +1,653 @@
+/*
+ * Linux I2C core ACPI support code
+ *
+ * Copyright (C) 2014 Intel Corp, Author: Lan Tianyu <tianyu.lan at intel.com>
+ *
+ * This program is free software; you can redistribute it and/or modify it
+ * under the terms of the GNU General Public License as published by the Free
+ * Software Foundation; either version 2 of the License, or (at your option)
+ * any later version.
+ */
+
+#include <linux/acpi.h>
+#include <linux/device.h>
+#include <linux/err.h>
+#include <linux/i2c.h>
+#include <linux/list.h>
+#include <linux/module.h>
+#include <linux/slab.h>
+
+#include "i2c-core.h"
+
+struct i2c_acpi_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;
+
+struct i2c_acpi_lookup {
+ struct i2c_board_info *info;
+ acpi_handle adapter_handle;
+ acpi_handle device_handle;
+ acpi_handle search_handle;
+ int n;
+ int index;
+ u32 speed;
+ u32 min_speed;
+};
+
+static int i2c_acpi_fill_info(struct acpi_resource *ares, void *data)
+{
+ struct i2c_acpi_lookup *lookup = data;
+ struct i2c_board_info *info = lookup->info;
+ struct acpi_resource_i2c_serialbus *sb;
+ acpi_status status;
+
+ if (info->addr || ares->type != ACPI_RESOURCE_TYPE_SERIAL_BUS)
+ return 1;
+
+ sb = &ares->data.i2c_serial_bus;
+ if (sb->type != ACPI_RESOURCE_SERIAL_TYPE_I2C)
+ return 1;
+
+ if (lookup->index != -1 && lookup->n++ != lookup->index)
+ return 1;
+
+ status = acpi_get_handle(lookup->device_handle,
+ sb->resource_source.string_ptr,
+ &lookup->adapter_handle);
+ if (!ACPI_SUCCESS(status))
+ return 1;
+
+ info->addr = sb->slave_address;
+ lookup->speed = sb->connection_speed;
+ if (sb->access_mode == ACPI_I2C_10BIT_MODE)
+ info->flags |= I2C_CLIENT_TEN;
+
+ return 1;
+}
+
+static int i2c_acpi_do_lookup(struct acpi_device *adev,
+ struct i2c_acpi_lookup *lookup)
+{
+ struct i2c_board_info *info = lookup->info;
+ struct list_head resource_list;
+ int ret;
+
+ if (acpi_bus_get_status(adev) || !adev->status.present ||
+ acpi_device_enumerated(adev))
+ return -EINVAL;
+
+ memset(info, 0, sizeof(*info));
+ lookup->device_handle = acpi_device_handle(adev);
+
+ /* Look up for I2cSerialBus resource */
+ INIT_LIST_HEAD(&resource_list);
+ ret = acpi_dev_get_resources(adev, &resource_list,
+ i2c_acpi_fill_info, lookup);
+ acpi_dev_free_resource_list(&resource_list);
+
+ if (ret < 0 || !info->addr)
+ return -EINVAL;
+
+ return 0;
+}
+
+static int i2c_acpi_get_info(struct acpi_device *adev,
+ struct i2c_board_info *info,
+ struct i2c_adapter *adapter,
+ acpi_handle *adapter_handle)
+{
+ struct list_head resource_list;
+ struct resource_entry *entry;
+ struct i2c_acpi_lookup lookup;
+ int ret;
+
+ memset(&lookup, 0, sizeof(lookup));
+ lookup.info = info;
+ lookup.index = -1;
+
+ ret = i2c_acpi_do_lookup(adev, &lookup);
+ if (ret)
+ return ret;
+
+ if (adapter) {
+ /* The adapter must match the one in I2cSerialBus() connector */
+ if (ACPI_HANDLE(&adapter->dev) != lookup.adapter_handle)
+ return -ENODEV;
+ } else {
+ struct acpi_device *adapter_adev;
+
+ /* The adapter must be present */
+ if (acpi_bus_get_device(lookup.adapter_handle, &adapter_adev))
+ return -ENODEV;
+ if (acpi_bus_get_status(adapter_adev) ||
+ !adapter_adev->status.present)
+ return -ENODEV;
+ }
+
+ info->fwnode = acpi_fwnode_handle(adev);
+ if (adapter_handle)
+ *adapter_handle = lookup.adapter_handle;
+
+ /* Then fill IRQ number if any */
+ INIT_LIST_HEAD(&resource_list);
+ ret = acpi_dev_get_resources(adev, &resource_list, NULL, NULL);
+ if (ret < 0)
+ return -EINVAL;
+
+ resource_list_for_each_entry(entry, &resource_list) {
+ if (resource_type(entry->res) == IORESOURCE_IRQ) {
+ info->irq = entry->res->start;
+ break;
+ }
+ }
+
+ acpi_dev_free_resource_list(&resource_list);
+
+ acpi_set_modalias(adev, dev_name(&adev->dev), info->type,
+ sizeof(info->type));
+
+ return 0;
+}
+
+static void i2c_acpi_register_device(struct i2c_adapter *adapter,
+ struct acpi_device *adev,
+ struct i2c_board_info *info)
+{
+ adev->power.flags.ignore_parent = true;
+ acpi_device_set_enumerated(adev);
+
+ 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));
+ }
+}
+
+static acpi_status i2c_acpi_add_device(acpi_handle handle, u32 level,
+ void *data, void **return_value)
+{
+ struct i2c_adapter *adapter = data;
+ struct acpi_device *adev;
+ struct i2c_board_info info;
+
+ if (acpi_bus_get_device(handle, &adev))
+ return AE_OK;
+
+ if (i2c_acpi_get_info(adev, &info, adapter, NULL))
+ return AE_OK;
+
+ i2c_acpi_register_device(adapter, adev, &info);
+
+ return AE_OK;
+}
+
+#define I2C_ACPI_MAX_SCAN_DEPTH 32
+
+/**
+ * i2c_acpi_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 i2c_acpi_register_devices(struct i2c_adapter *adap)
+{
+ acpi_status status;
+
+ if (!has_acpi_companion(&adap->dev))
+ return;
+
+ status = acpi_walk_namespace(ACPI_TYPE_DEVICE, ACPI_ROOT_OBJECT,
+ I2C_ACPI_MAX_SCAN_DEPTH,
+ i2c_acpi_add_device, NULL,
+ adap, NULL);
+ if (ACPI_FAILURE(status))
+ dev_warn(&adap->dev, "failed to enumerate I2C slaves\n");
+}
+
+static acpi_status i2c_acpi_lookup_speed(acpi_handle handle, u32 level,
+ void *data, void **return_value)
+{
+ struct i2c_acpi_lookup *lookup = data;
+ struct acpi_device *adev;
+
+ if (acpi_bus_get_device(handle, &adev))
+ return AE_OK;
+
+ if (i2c_acpi_do_lookup(adev, lookup))
+ return AE_OK;
+
+ if (lookup->search_handle != lookup->adapter_handle)
+ return AE_OK;
+
+ if (lookup->speed <= lookup->min_speed)
+ lookup->min_speed = lookup->speed;
+
+ return AE_OK;
+}
+
+/**
+ * i2c_acpi_find_bus_speed - find I2C bus speed from ACPI
+ * @dev: The device owning the bus
+ *
+ * Find the I2C bus speed by walking the ACPI namespace for all I2C slaves
+ * devices connected to this bus and use the speed of slowest device.
+ *
+ * Returns the speed in Hz or zero
+ */
+u32 i2c_acpi_find_bus_speed(struct device *dev)
+{
+ struct i2c_acpi_lookup lookup;
+ struct i2c_board_info dummy;
+ acpi_status status;
+
+ if (!has_acpi_companion(dev))
+ return 0;
+
+ memset(&lookup, 0, sizeof(lookup));
+ lookup.search_handle = ACPI_HANDLE(dev);
+ lookup.min_speed = UINT_MAX;
+ lookup.info = &dummy;
+ lookup.index = -1;
+
+ status = acpi_walk_namespace(ACPI_TYPE_DEVICE, ACPI_ROOT_OBJECT,
+ I2C_ACPI_MAX_SCAN_DEPTH,
+ i2c_acpi_lookup_speed, NULL,
+ &lookup, NULL);
+
+ if (ACPI_FAILURE(status)) {
+ dev_warn(dev, "unable to find I2C bus speed from ACPI\n");
+ return 0;
+ }
+
+ return lookup.min_speed != UINT_MAX ? lookup.min_speed : 0;
+}
+EXPORT_SYMBOL_GPL(i2c_acpi_find_bus_speed);
+
+static int i2c_acpi_match_adapter(struct device *dev, void *data)
+{
+ struct i2c_adapter *adapter = i2c_verify_adapter(dev);
+
+ if (!adapter)
+ return 0;
+
+ return ACPI_HANDLE(dev) == (acpi_handle)data;
+}
+
+static int i2c_acpi_match_device(struct device *dev, void *data)
+{
+ return ACPI_COMPANION(dev) == data;
+}
+
+static struct i2c_adapter *i2c_acpi_find_adapter_by_handle(acpi_handle handle)
+{
+ struct device *dev;
+
+ dev = bus_find_device(&i2c_bus_type, NULL, handle,
+ i2c_acpi_match_adapter);
+ return dev ? i2c_verify_adapter(dev) : NULL;
+}
+
+static struct i2c_client *i2c_acpi_find_client_by_adev(struct acpi_device *adev)
+{
+ struct device *dev;
+
+ dev = bus_find_device(&i2c_bus_type, NULL, adev, i2c_acpi_match_device);
+ return dev ? i2c_verify_client(dev) : NULL;
+}
+
+static int i2c_acpi_notify(struct notifier_block *nb, unsigned long value,
+ void *arg)
+{
+ struct acpi_device *adev = arg;
+ struct i2c_board_info info;
+ acpi_handle adapter_handle;
+ struct i2c_adapter *adapter;
+ struct i2c_client *client;
+
+ switch (value) {
+ case ACPI_RECONFIG_DEVICE_ADD:
+ if (i2c_acpi_get_info(adev, &info, NULL, &adapter_handle))
+ break;
+
+ adapter = i2c_acpi_find_adapter_by_handle(adapter_handle);
+ if (!adapter)
+ break;
+
+ i2c_acpi_register_device(adapter, adev, &info);
+ break;
+ case ACPI_RECONFIG_DEVICE_REMOVE:
+ if (!acpi_device_enumerated(adev))
+ break;
+
+ client = i2c_acpi_find_client_by_adev(adev);
+ if (!client)
+ break;
+
+ i2c_unregister_device(client);
+ put_device(&client->dev);
+ break;
+ }
+
+ return NOTIFY_OK;
+}
+
+struct notifier_block i2c_acpi_notifier = {
+ .notifier_call = i2c_acpi_notify,
+};
+
+/**
+ * i2c_acpi_new_device - Create i2c-client for the Nth I2cSerialBus resource
+ * @dev: Device owning the ACPI resources to get the client from
+ * @index: Index of ACPI resource to get
+ * @info: describes the I2C device; note this is modified (addr gets set)
+ * Context: can sleep
+ *
+ * By default the i2c subsys creates an i2c-client for the first I2cSerialBus
+ * resource of an acpi_device, but some acpi_devices have multiple I2cSerialBus
+ * resources, in that case this function can be used to create an i2c-client
+ * for other I2cSerialBus resources in the Current Resource Settings table.
+ *
+ * Also see i2c_new_device, which this function calls to create the i2c-client.
+ *
+ * Returns a pointer to the new i2c-client, or NULL if the adapter is not found.
+ */
+struct i2c_client *i2c_acpi_new_device(struct device *dev, int index,
+ struct i2c_board_info *info)
+{
+ struct i2c_acpi_lookup lookup;
+ struct i2c_adapter *adapter;
+ struct acpi_device *adev;
+ LIST_HEAD(resource_list);
+ int ret;
+
+ adev = ACPI_COMPANION(dev);
+ if (!adev)
+ return NULL;
+
+ memset(&lookup, 0, sizeof(lookup));
+ lookup.info = info;
+ lookup.device_handle = acpi_device_handle(adev);
+ lookup.index = index;
+
+ ret = acpi_dev_get_resources(adev, &resource_list,
+ i2c_acpi_fill_info, &lookup);
+ acpi_dev_free_resource_list(&resource_list);
+
+ if (ret < 0 || !info->addr)
+ return NULL;
+
+ adapter = i2c_acpi_find_adapter_by_handle(lookup.adapter_handle);
+ if (!adapter)
+ return NULL;
+
+ return i2c_new_device(adapter, info);
+}
+EXPORT_SYMBOL_GPL(i2c_acpi_new_device);
+
+#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
+i2c_acpi_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 i2c_acpi_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;
+ int status;
+
+ ret = acpi_buffer_to_resource(info->connection, info->length, &ares);
+ if (ACPI_FAILURE(ret))
+ return ret;
+
+ client = kzalloc(sizeof(*client), GFP_KERNEL);
+ if (!client) {
+ ret = AE_NO_MEMORY;
+ goto err;
+ }
+
+ 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;
+ }
+
+ client->adapter = adapter;
+ client->addr = sb->slave_address;
+
+ 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:
+ dev_warn(&adapter->dev, "protocol 0x%02x not supported for client 0x%02x\n",
+ accessor_type, client->addr);
+ ret = AE_BAD_PARAMETER;
+ goto err;
+ }
+
+ gsb->status = status;
+
+ err:
+ kfree(client);
+ ACPI_FREE(ares);
+ return ret;
+}
+
+
+int i2c_acpi_install_space_handler(struct i2c_adapter *adapter)
+{
+ acpi_handle handle;
+ struct i2c_acpi_handler_data *data;
+ acpi_status status;
+
+ if (!adapter->dev.parent)
+ return -ENODEV;
+
+ handle = ACPI_HANDLE(adapter->dev.parent);
+
+ if (!handle)
+ return -ENODEV;
+
+ data = kzalloc(sizeof(struct i2c_acpi_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,
+ &i2c_acpi_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;
+ }
+
+ acpi_walk_dep_device_list(handle);
+ return 0;
+}
+
+void i2c_acpi_remove_space_handler(struct i2c_adapter *adapter)
+{
+ acpi_handle handle;
+ struct i2c_acpi_handler_data *data;
+ acpi_status status;
+
+ if (!adapter->dev.parent)
+ return;
+
+ handle = ACPI_HANDLE(adapter->dev.parent);
+
+ if (!handle)
+ return;
+
+ acpi_remove_address_space_handler(handle,
+ ACPI_ADR_SPACE_GSBUS,
+ &i2c_acpi_space_handler);
+
+ status = acpi_bus_get_private_data(handle, (void **)&data);
+ if (ACPI_SUCCESS(status))
+ kfree(data);
+
+ acpi_bus_detach_private_data(handle);
+}
+#endif /* CONFIG_ACPI_I2C_OPREGION */
diff --git a/drivers/i2c/i2c-core-base.c b/drivers/i2c/i2c-core-base.c
index 461451da106504..ac7b95e4cda75d 100644
--- a/drivers/i2c/i2c-core-base.c
+++ b/drivers/i2c/i2c-core-base.c
@@ -16,8 +16,6 @@
/* With some changes from Kyösti Mälkki <kmalkki at cc.hut.fi>.
Mux support by Rodolfo Giometti <giometti at enneenne.com> and
Michael Lawnick <michael.lawnick.ext at nsn.com>
- I2C ACPI code Copyright (C) 2014 Intel Corp
- Author: Lan Tianyu <tianyu.lan at intel.com>
*/
#define pr_fmt(fmt) "i2c-core: " fmt
@@ -83,652 +81,6 @@ void i2c_transfer_trace_unreg(void)
static_key_slow_dec(&i2c_trace_msg);
}
-#if defined(CONFIG_ACPI)
-struct i2c_acpi_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;
-
-struct i2c_acpi_lookup {
- struct i2c_board_info *info;
- acpi_handle adapter_handle;
- acpi_handle device_handle;
- acpi_handle search_handle;
- int n;
- int index;
- u32 speed;
- u32 min_speed;
-};
-
-static int i2c_acpi_fill_info(struct acpi_resource *ares, void *data)
-{
- struct i2c_acpi_lookup *lookup = data;
- struct i2c_board_info *info = lookup->info;
- struct acpi_resource_i2c_serialbus *sb;
- acpi_status status;
-
- if (info->addr || ares->type != ACPI_RESOURCE_TYPE_SERIAL_BUS)
- return 1;
-
- sb = &ares->data.i2c_serial_bus;
- if (sb->type != ACPI_RESOURCE_SERIAL_TYPE_I2C)
- return 1;
-
- if (lookup->index != -1 && lookup->n++ != lookup->index)
- return 1;
-
- status = acpi_get_handle(lookup->device_handle,
- sb->resource_source.string_ptr,
- &lookup->adapter_handle);
- if (!ACPI_SUCCESS(status))
- return 1;
-
- info->addr = sb->slave_address;
- lookup->speed = sb->connection_speed;
- if (sb->access_mode == ACPI_I2C_10BIT_MODE)
- info->flags |= I2C_CLIENT_TEN;
-
- return 1;
-}
-
-static int i2c_acpi_do_lookup(struct acpi_device *adev,
- struct i2c_acpi_lookup *lookup)
-{
- struct i2c_board_info *info = lookup->info;
- struct list_head resource_list;
- int ret;
-
- if (acpi_bus_get_status(adev) || !adev->status.present ||
- acpi_device_enumerated(adev))
- return -EINVAL;
-
- memset(info, 0, sizeof(*info));
- lookup->device_handle = acpi_device_handle(adev);
-
- /* Look up for I2cSerialBus resource */
- INIT_LIST_HEAD(&resource_list);
- ret = acpi_dev_get_resources(adev, &resource_list,
- i2c_acpi_fill_info, lookup);
- acpi_dev_free_resource_list(&resource_list);
-
- if (ret < 0 || !info->addr)
- return -EINVAL;
-
- return 0;
-}
-
-static int i2c_acpi_get_info(struct acpi_device *adev,
- struct i2c_board_info *info,
- struct i2c_adapter *adapter,
- acpi_handle *adapter_handle)
-{
- struct list_head resource_list;
- struct resource_entry *entry;
- struct i2c_acpi_lookup lookup;
- int ret;
-
- memset(&lookup, 0, sizeof(lookup));
- lookup.info = info;
- lookup.index = -1;
-
- ret = i2c_acpi_do_lookup(adev, &lookup);
- if (ret)
- return ret;
-
- if (adapter) {
- /* The adapter must match the one in I2cSerialBus() connector */
- if (ACPI_HANDLE(&adapter->dev) != lookup.adapter_handle)
- return -ENODEV;
- } else {
- struct acpi_device *adapter_adev;
-
- /* The adapter must be present */
- if (acpi_bus_get_device(lookup.adapter_handle, &adapter_adev))
- return -ENODEV;
- if (acpi_bus_get_status(adapter_adev) ||
- !adapter_adev->status.present)
- return -ENODEV;
- }
-
- info->fwnode = acpi_fwnode_handle(adev);
- if (adapter_handle)
- *adapter_handle = lookup.adapter_handle;
-
- /* Then fill IRQ number if any */
- INIT_LIST_HEAD(&resource_list);
- ret = acpi_dev_get_resources(adev, &resource_list, NULL, NULL);
- if (ret < 0)
- return -EINVAL;
-
- resource_list_for_each_entry(entry, &resource_list) {
- if (resource_type(entry->res) == IORESOURCE_IRQ) {
- info->irq = entry->res->start;
- break;
- }
- }
-
- acpi_dev_free_resource_list(&resource_list);
-
- acpi_set_modalias(adev, dev_name(&adev->dev), info->type,
- sizeof(info->type));
-
- return 0;
-}
-
-static void i2c_acpi_register_device(struct i2c_adapter *adapter,
- struct acpi_device *adev,
- struct i2c_board_info *info)
-{
- adev->power.flags.ignore_parent = true;
- acpi_device_set_enumerated(adev);
-
- 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));
- }
-}
-
-static acpi_status i2c_acpi_add_device(acpi_handle handle, u32 level,
- void *data, void **return_value)
-{
- struct i2c_adapter *adapter = data;
- struct acpi_device *adev;
- struct i2c_board_info info;
-
- if (acpi_bus_get_device(handle, &adev))
- return AE_OK;
-
- if (i2c_acpi_get_info(adev, &info, adapter, NULL))
- return AE_OK;
-
- i2c_acpi_register_device(adapter, adev, &info);
-
- return AE_OK;
-}
-
-#define I2C_ACPI_MAX_SCAN_DEPTH 32
-
-/**
- * i2c_acpi_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.
- */
-static void i2c_acpi_register_devices(struct i2c_adapter *adap)
-{
- acpi_status status;
-
- if (!has_acpi_companion(&adap->dev))
- return;
-
- status = acpi_walk_namespace(ACPI_TYPE_DEVICE, ACPI_ROOT_OBJECT,
- I2C_ACPI_MAX_SCAN_DEPTH,
- i2c_acpi_add_device, NULL,
- adap, NULL);
- if (ACPI_FAILURE(status))
- dev_warn(&adap->dev, "failed to enumerate I2C slaves\n");
-}
-
-static acpi_status i2c_acpi_lookup_speed(acpi_handle handle, u32 level,
- void *data, void **return_value)
-{
- struct i2c_acpi_lookup *lookup = data;
- struct acpi_device *adev;
-
- if (acpi_bus_get_device(handle, &adev))
- return AE_OK;
-
- if (i2c_acpi_do_lookup(adev, lookup))
- return AE_OK;
-
- if (lookup->search_handle != lookup->adapter_handle)
- return AE_OK;
-
- if (lookup->speed <= lookup->min_speed)
- lookup->min_speed = lookup->speed;
-
- return AE_OK;
-}
-
-/**
- * i2c_acpi_find_bus_speed - find I2C bus speed from ACPI
- * @dev: The device owning the bus
- *
- * Find the I2C bus speed by walking the ACPI namespace for all I2C slaves
- * devices connected to this bus and use the speed of slowest device.
- *
- * Returns the speed in Hz or zero
- */
-u32 i2c_acpi_find_bus_speed(struct device *dev)
-{
- struct i2c_acpi_lookup lookup;
- struct i2c_board_info dummy;
- acpi_status status;
-
- if (!has_acpi_companion(dev))
- return 0;
-
- memset(&lookup, 0, sizeof(lookup));
- lookup.search_handle = ACPI_HANDLE(dev);
- lookup.min_speed = UINT_MAX;
- lookup.info = &dummy;
- lookup.index = -1;
-
- status = acpi_walk_namespace(ACPI_TYPE_DEVICE, ACPI_ROOT_OBJECT,
- I2C_ACPI_MAX_SCAN_DEPTH,
- i2c_acpi_lookup_speed, NULL,
- &lookup, NULL);
-
- if (ACPI_FAILURE(status)) {
- dev_warn(dev, "unable to find I2C bus speed from ACPI\n");
- return 0;
- }
-
- return lookup.min_speed != UINT_MAX ? lookup.min_speed : 0;
-}
-EXPORT_SYMBOL_GPL(i2c_acpi_find_bus_speed);
-
-static int i2c_acpi_match_adapter(struct device *dev, void *data)
-{
- struct i2c_adapter *adapter = i2c_verify_adapter(dev);
-
- if (!adapter)
- return 0;
-
- return ACPI_HANDLE(dev) == (acpi_handle)data;
-}
-
-static int i2c_acpi_match_device(struct device *dev, void *data)
-{
- return ACPI_COMPANION(dev) == data;
-}
-
-static struct i2c_adapter *i2c_acpi_find_adapter_by_handle(acpi_handle handle)
-{
- struct device *dev;
-
- dev = bus_find_device(&i2c_bus_type, NULL, handle,
- i2c_acpi_match_adapter);
- return dev ? i2c_verify_adapter(dev) : NULL;
-}
-
-static struct i2c_client *i2c_acpi_find_client_by_adev(struct acpi_device *adev)
-{
- struct device *dev;
-
- dev = bus_find_device(&i2c_bus_type, NULL, adev, i2c_acpi_match_device);
- return dev ? i2c_verify_client(dev) : NULL;
-}
-
-static int i2c_acpi_notify(struct notifier_block *nb, unsigned long value,
- void *arg)
-{
- struct acpi_device *adev = arg;
- struct i2c_board_info info;
- acpi_handle adapter_handle;
- struct i2c_adapter *adapter;
- struct i2c_client *client;
-
- switch (value) {
- case ACPI_RECONFIG_DEVICE_ADD:
- if (i2c_acpi_get_info(adev, &info, NULL, &adapter_handle))
- break;
-
- adapter = i2c_acpi_find_adapter_by_handle(adapter_handle);
- if (!adapter)
- break;
-
- i2c_acpi_register_device(adapter, adev, &info);
- break;
- case ACPI_RECONFIG_DEVICE_REMOVE:
- if (!acpi_device_enumerated(adev))
- break;
-
- client = i2c_acpi_find_client_by_adev(adev);
- if (!client)
- break;
-
- i2c_unregister_device(client);
- put_device(&client->dev);
- break;
- }
-
- return NOTIFY_OK;
-}
-
-static struct notifier_block i2c_acpi_notifier = {
- .notifier_call = i2c_acpi_notify,
-};
-
-/**
- * i2c_acpi_new_device - Create i2c-client for the Nth I2cSerialBus resource
- * @dev: Device owning the ACPI resources to get the client from
- * @index: Index of ACPI resource to get
- * @info: describes the I2C device; note this is modified (addr gets set)
- * Context: can sleep
- *
- * By default the i2c subsys creates an i2c-client for the first I2cSerialBus
- * resource of an acpi_device, but some acpi_devices have multiple I2cSerialBus
- * resources, in that case this function can be used to create an i2c-client
- * for other I2cSerialBus resources in the Current Resource Settings table.
- *
- * Also see i2c_new_device, which this function calls to create the i2c-client.
- *
- * Returns a pointer to the new i2c-client, or NULL if the adapter is not found.
- */
-struct i2c_client *i2c_acpi_new_device(struct device *dev, int index,
- struct i2c_board_info *info)
-{
- struct i2c_acpi_lookup lookup;
- struct i2c_adapter *adapter;
- struct acpi_device *adev;
- LIST_HEAD(resource_list);
- int ret;
-
- adev = ACPI_COMPANION(dev);
- if (!adev)
- return NULL;
-
- memset(&lookup, 0, sizeof(lookup));
- lookup.info = info;
- lookup.device_handle = acpi_device_handle(adev);
- lookup.index = index;
-
- ret = acpi_dev_get_resources(adev, &resource_list,
- i2c_acpi_fill_info, &lookup);
- acpi_dev_free_resource_list(&resource_list);
-
- if (ret < 0 || !info->addr)
- return NULL;
-
- adapter = i2c_acpi_find_adapter_by_handle(lookup.adapter_handle);
- if (!adapter)
- return NULL;
-
- return i2c_new_device(adapter, info);
-}
-EXPORT_SYMBOL_GPL(i2c_acpi_new_device);
-#else /* CONFIG_ACPI */
-static inline void i2c_acpi_register_devices(struct i2c_adapter *adap) { }
-extern struct notifier_block i2c_acpi_notifier;
-#endif /* CONFIG_ACPI */
-
-#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
-i2c_acpi_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 i2c_acpi_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;
- int status;
-
- ret = acpi_buffer_to_resource(info->connection, info->length, &ares);
- if (ACPI_FAILURE(ret))
- return ret;
-
- client = kzalloc(sizeof(*client), GFP_KERNEL);
- if (!client) {
- ret = AE_NO_MEMORY;
- goto err;
- }
-
- 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;
- }
-
- client->adapter = adapter;
- client->addr = sb->slave_address;
-
- 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:
- dev_warn(&adapter->dev, "protocol 0x%02x not supported for client 0x%02x\n",
- accessor_type, client->addr);
- ret = AE_BAD_PARAMETER;
- goto err;
- }
-
- gsb->status = status;
-
- err:
- kfree(client);
- ACPI_FREE(ares);
- return ret;
-}
-
-
-static int i2c_acpi_install_space_handler(struct i2c_adapter *adapter)
-{
- acpi_handle handle;
- struct i2c_acpi_handler_data *data;
- acpi_status status;
-
- if (!adapter->dev.parent)
- return -ENODEV;
-
- handle = ACPI_HANDLE(adapter->dev.parent);
-
- if (!handle)
- return -ENODEV;
-
- data = kzalloc(sizeof(struct i2c_acpi_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,
- &i2c_acpi_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;
- }
-
- acpi_walk_dep_device_list(handle);
- return 0;
-}
-
-static void i2c_acpi_remove_space_handler(struct i2c_adapter *adapter)
-{
- acpi_handle handle;
- struct i2c_acpi_handler_data *data;
- acpi_status status;
-
- if (!adapter->dev.parent)
- return;
-
- handle = ACPI_HANDLE(adapter->dev.parent);
-
- if (!handle)
- return;
-
- acpi_remove_address_space_handler(handle,
- ACPI_ADR_SPACE_GSBUS,
- &i2c_acpi_space_handler);
-
- status = acpi_bus_get_private_data(handle, (void **)&data);
- if (ACPI_SUCCESS(status))
- kfree(data);
-
- acpi_bus_detach_private_data(handle);
-}
-#else /* CONFIG_ACPI_I2C_OPREGION */
-static inline void i2c_acpi_remove_space_handler(struct i2c_adapter *adapter)
-{ }
-
-static inline int i2c_acpi_install_space_handler(struct i2c_adapter *adapter)
-{ return 0; }
-#endif /* CONFIG_ACPI_I2C_OPREGION */
-
-/* ------------------------------------------------------------------------- */
-
const struct i2c_device_id *i2c_match_id(const struct i2c_device_id *id,
const struct i2c_client *client)
{
diff --git a/drivers/i2c/i2c-core.h b/drivers/i2c/i2c-core.h
index 22151c88e88599..3b63f5e5b89cbd 100644
--- a/drivers/i2c/i2c-core.h
+++ b/drivers/i2c/i2c-core.h
@@ -30,6 +30,21 @@ extern int __i2c_first_dynamic_bus_num;
int i2c_check_addr_validity(unsigned addr, unsigned short flags);
int i2c_check_7bit_addr_validity_strict(unsigned short addr);
+#ifdef CONFIG_ACPI
+void i2c_acpi_register_devices(struct i2c_adapter *adap);
+#else /* CONFIG_ACPI */
+static inline void i2c_acpi_register_devices(struct i2c_adapter *adap) { }
+#endif /* CONFIG_ACPI */
+extern struct notifier_block i2c_acpi_notifier;
+
+#ifdef CONFIG_ACPI_I2C_OPREGION
+int i2c_acpi_install_space_handler(struct i2c_adapter *adapter);
+void i2c_acpi_remove_space_handler(struct i2c_adapter *adapter);
+#else /* CONFIG_ACPI_I2C_OPREGION */
+static inline int i2c_acpi_install_space_handler(struct i2c_adapter *adapter) { return 0; }
+static inline void i2c_acpi_remove_space_handler(struct i2c_adapter *adapter) { }
+#endif /* CONFIG_ACPI_I2C_OPREGION */
+
#ifdef CONFIG_OF
void of_i2c_register_devices(struct i2c_adapter *adap);
#else
--
2.11.0
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