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path: root/drivers/i2c/i2c-core.c
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Diffstat (limited to 'drivers/i2c/i2c-core.c')
-rw-r--r--drivers/i2c/i2c-core.c62
1 files changed, 59 insertions, 3 deletions
diff --git a/drivers/i2c/i2c-core.c b/drivers/i2c/i2c-core.c
index 679a31fcb6d6..82576aaccc90 100644
--- a/drivers/i2c/i2c-core.c
+++ b/drivers/i2c/i2c-core.c
@@ -111,6 +111,8 @@ struct i2c_acpi_lookup {
acpi_handle adapter_handle;
acpi_handle device_handle;
acpi_handle search_handle;
+ int n;
+ int index;
u32 speed;
u32 min_speed;
};
@@ -129,6 +131,9 @@ static int i2c_acpi_fill_info(struct acpi_resource *ares, void *data)
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);
@@ -181,6 +186,7 @@ static int i2c_acpi_get_info(struct acpi_device *adev,
memset(&lookup, 0, sizeof(lookup));
lookup.info = info;
+ lookup.index = -1;
ret = i2c_acpi_do_lookup(adev, &lookup);
if (ret)
@@ -327,6 +333,7 @@ u32 i2c_acpi_find_bus_speed(struct device *dev)
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,
@@ -413,6 +420,55 @@ static int i2c_acpi_notify(struct notifier_block *nb, unsigned long value,
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;
@@ -928,7 +984,9 @@ static int i2c_device_probe(struct device *dev)
if (!client)
return 0;
- if (!client->irq) {
+ driver = to_i2c_driver(dev->driver);
+
+ if (!client->irq && !driver->disable_i2c_core_irq_mapping) {
int irq = -ENOENT;
if (client->flags & I2C_CLIENT_HOST_NOTIFY) {
@@ -950,8 +1008,6 @@ static int i2c_device_probe(struct device *dev)
client->irq = irq;
}
- driver = to_i2c_driver(dev->driver);
-
/*
* An I2C ID table is not mandatory, if and only if, a suitable Device
* Tree match table entry is supplied for the probing device.