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Diffstat (limited to 'drivers/i2c/i2c-core.c')
-rw-r--r--drivers/i2c/i2c-core.c495
1 files changed, 389 insertions, 106 deletions
diff --git a/drivers/i2c/i2c-core.c b/drivers/i2c/i2c-core.c
index 66aa83b99383..f43b4e11647a 100644
--- a/drivers/i2c/i2c-core.c
+++ b/drivers/i2c/i2c-core.c
@@ -10,12 +10,7 @@
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.
-
- You should have received a copy of the GNU General Public License
- along with this program; if not, write to the Free Software
- Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston,
- MA 02110-1301 USA. */
+ GNU General Public License for more details. */
/* ------------------------------------------------------------------------- */
/* With some changes from Kyösti Mälkki <kmalkki@cc.hut.fi>.
@@ -27,6 +22,8 @@
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>
@@ -48,6 +45,7 @@
#include <linux/irqflags.h>
#include <linux/rwsem.h>
#include <linux/pm_runtime.h>
+#include <linux/pm_domain.h>
#include <linux/acpi.h>
#include <linux/jump_label.h>
#include <asm/uaccess.h>
@@ -78,6 +76,368 @@ 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.
+ */
+static 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");
+}
+
+#else /* CONFIG_ACPI */
+static inline void acpi_i2c_register_devices(struct i2c_adapter *adap) { }
+#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
+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;
+}
+
+
+static int acpi_i2c_install_space_handler(struct i2c_adapter *adapter)
+{
+ acpi_handle handle;
+ struct acpi_i2c_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 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;
+}
+
+static void acpi_i2c_remove_space_handler(struct i2c_adapter *adapter)
+{
+ acpi_handle handle;
+ struct acpi_i2c_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,
+ &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);
+}
+#else /* CONFIG_ACPI_I2C_OPREGION */
+static inline void acpi_i2c_remove_space_handler(struct i2c_adapter *adapter)
+{ }
+
+static inline int acpi_i2c_install_space_handler(struct i2c_adapter *adapter)
+{ return 0; }
+#endif /* CONFIG_ACPI_I2C_OPREGION */
+
/* ------------------------------------------------------------------------- */
static const struct i2c_device_id *i2c_match_id(const struct i2c_device_id *id,
@@ -279,10 +639,13 @@ static int i2c_device_probe(struct device *dev)
if (status < 0)
return status;
- acpi_dev_pm_attach(&client->dev, true);
- status = driver->probe(client, i2c_match_id(driver->id_table, client));
- if (status)
- acpi_dev_pm_detach(&client->dev, true);
+ status = dev_pm_domain_attach(&client->dev, true);
+ if (status != -EPROBE_DEFER) {
+ status = driver->probe(client, i2c_match_id(driver->id_table,
+ client));
+ if (status)
+ dev_pm_domain_detach(&client->dev, true);
+ }
return status;
}
@@ -302,7 +665,10 @@ static int i2c_device_remove(struct device *dev)
status = driver->remove(client);
}
- acpi_dev_pm_detach(&client->dev, true);
+ if (dev->of_node)
+ irq_dispose_mapping(client->irq);
+
+ dev_pm_domain_detach(&client->dev, true);
return status;
}
@@ -1097,101 +1463,6 @@ EXPORT_SYMBOL(of_find_i2c_adapter_by_node);
static void of_i2c_register_devices(struct i2c_adapter *adap) { }
#endif /* CONFIG_OF */
-/* ACPI support code */
-
-#if IS_ENABLED(CONFIG_ACPI)
-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.
- */
-static 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");
-}
-#else
-static inline void acpi_i2c_register_devices(struct i2c_adapter *adap) {}
-#endif /* CONFIG_ACPI */
-
static int i2c_do_add_adapter(struct i2c_driver *driver,
struct i2c_adapter *adap)
{
@@ -1298,6 +1569,7 @@ exit_recovery:
/* create pre-declared device nodes */
of_i2c_register_devices(adap);
acpi_i2c_register_devices(adap);
+ acpi_i2c_install_space_handler(adap);
if (adap->nr < __i2c_first_dynamic_bus_num)
i2c_scan_static_board_info(adap);
@@ -1471,6 +1743,7 @@ void i2c_del_adapter(struct i2c_adapter *adap)
return;
}
+ acpi_i2c_remove_space_handler(adap);
/* Tell drivers about this removal */
mutex_lock(&core_lock);
bus_for_each_drv(&i2c_bus_type, NULL, adap,
@@ -2013,6 +2286,16 @@ static int i2c_detect(struct i2c_adapter *adapter, struct i2c_driver *driver)
if (!driver->detect || !address_list)
return 0;
+ /* Warn that the adapter lost class based instantiation */
+ if (adapter->class == I2C_CLASS_DEPRECATED) {
+ dev_dbg(&adapter->dev,
+ "This adapter dropped support for I2C classes and "
+ "won't auto-detect %s devices anymore. If you need it, check "
+ "'Documentation/i2c/instantiating-devices' for alternatives.\n",
+ driver->driver.name);
+ return 0;
+ }
+
/* Stop here if the classes do not match */
if (!(adapter->class & driver->class))
return 0;