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Diffstat (limited to 'drivers/i2c/i2c-core.c')
-rw-r--r--drivers/i2c/i2c-core.c319
1 files changed, 182 insertions, 137 deletions
diff --git a/drivers/i2c/i2c-core.c b/drivers/i2c/i2c-core.c
index 4099b2b8c392..e0f833cca3f1 100644
--- a/drivers/i2c/i2c-core.c
+++ b/drivers/i2c/i2c-core.c
@@ -40,12 +40,11 @@
#include "i2c-core.h"
-/* core_lock protects i2c_adapter_idr, userspace_devices, and guarantees
+/* core_lock protects i2c_adapter_idr, and guarantees
that device detection, deletion of detected devices, and attach_adapter
and detach_adapter calls are serialized */
static DEFINE_MUTEX(core_lock);
static DEFINE_IDR(i2c_adapter_idr);
-static LIST_HEAD(userspace_devices);
static struct device_type i2c_client_type;
static int i2c_check_addr(struct i2c_adapter *adapter, int addr);
@@ -117,8 +116,10 @@ static int i2c_device_probe(struct device *dev)
dev_dbg(dev, "probe\n");
status = driver->probe(client, i2c_match_id(driver->id_table, client));
- if (status)
+ if (status) {
client->driver = NULL;
+ i2c_set_clientdata(client, NULL);
+ }
return status;
}
@@ -139,8 +140,10 @@ static int i2c_device_remove(struct device *dev)
dev->driver = NULL;
status = 0;
}
- if (status == 0)
+ if (status == 0) {
client->driver = NULL;
+ i2c_set_clientdata(client, NULL);
+ }
return status;
}
@@ -156,106 +159,130 @@ static void i2c_device_shutdown(struct device *dev)
driver->shutdown(client);
}
-#ifdef CONFIG_SUSPEND
-static int i2c_device_pm_suspend(struct device *dev)
+#ifdef CONFIG_PM_SLEEP
+static int i2c_legacy_suspend(struct device *dev, pm_message_t mesg)
{
- const struct dev_pm_ops *pm;
+ struct i2c_client *client = i2c_verify_client(dev);
+ struct i2c_driver *driver;
- if (!dev->driver)
+ if (!client || !dev->driver)
return 0;
- pm = dev->driver->pm;
- if (!pm || !pm->suspend)
+ driver = to_i2c_driver(dev->driver);
+ if (!driver->suspend)
return 0;
- return pm->suspend(dev);
+ return driver->suspend(client, mesg);
}
-static int i2c_device_pm_resume(struct device *dev)
+static int i2c_legacy_resume(struct device *dev)
{
- const struct dev_pm_ops *pm;
+ struct i2c_client *client = i2c_verify_client(dev);
+ struct i2c_driver *driver;
- if (!dev->driver)
+ if (!client || !dev->driver)
return 0;
- pm = dev->driver->pm;
- if (!pm || !pm->resume)
+ driver = to_i2c_driver(dev->driver);
+ if (!driver->resume)
return 0;
- return pm->resume(dev);
+ return driver->resume(client);
}
-#else
-#define i2c_device_pm_suspend NULL
-#define i2c_device_pm_resume NULL
-#endif
-#ifdef CONFIG_PM_RUNTIME
-static int i2c_device_runtime_suspend(struct device *dev)
+static int i2c_device_pm_suspend(struct device *dev)
{
- const struct dev_pm_ops *pm;
+ const struct dev_pm_ops *pm = dev->driver ? dev->driver->pm : NULL;
- if (!dev->driver)
- return 0;
- pm = dev->driver->pm;
- if (!pm || !pm->runtime_suspend)
+ if (pm_runtime_suspended(dev))
return 0;
- return pm->runtime_suspend(dev);
-}
-static int i2c_device_runtime_resume(struct device *dev)
-{
- const struct dev_pm_ops *pm;
+ if (pm)
+ return pm->suspend ? pm->suspend(dev) : 0;
- if (!dev->driver)
- return 0;
- pm = dev->driver->pm;
- if (!pm || !pm->runtime_resume)
- return 0;
- return pm->runtime_resume(dev);
+ return i2c_legacy_suspend(dev, PMSG_SUSPEND);
}
-static int i2c_device_runtime_idle(struct device *dev)
+static int i2c_device_pm_resume(struct device *dev)
{
- const struct dev_pm_ops *pm = NULL;
+ const struct dev_pm_ops *pm = dev->driver ? dev->driver->pm : NULL;
int ret;
- if (dev->driver)
- pm = dev->driver->pm;
- if (pm && pm->runtime_idle) {
- ret = pm->runtime_idle(dev);
- if (ret)
- return ret;
+ if (pm)
+ ret = pm->resume ? pm->resume(dev) : 0;
+ else
+ ret = i2c_legacy_resume(dev);
+
+ if (!ret) {
+ pm_runtime_disable(dev);
+ pm_runtime_set_active(dev);
+ pm_runtime_enable(dev);
}
- return pm_runtime_suspend(dev);
+ return ret;
}
-#else
-#define i2c_device_runtime_suspend NULL
-#define i2c_device_runtime_resume NULL
-#define i2c_device_runtime_idle NULL
-#endif
-static int i2c_device_suspend(struct device *dev, pm_message_t mesg)
+static int i2c_device_pm_freeze(struct device *dev)
{
- struct i2c_client *client = i2c_verify_client(dev);
- struct i2c_driver *driver;
+ const struct dev_pm_ops *pm = dev->driver ? dev->driver->pm : NULL;
- if (!client || !dev->driver)
+ if (pm_runtime_suspended(dev))
return 0;
- driver = to_i2c_driver(dev->driver);
- if (!driver->suspend)
- return 0;
- return driver->suspend(client, mesg);
+
+ if (pm)
+ return pm->freeze ? pm->freeze(dev) : 0;
+
+ return i2c_legacy_suspend(dev, PMSG_FREEZE);
}
-static int i2c_device_resume(struct device *dev)
+static int i2c_device_pm_thaw(struct device *dev)
{
- struct i2c_client *client = i2c_verify_client(dev);
- struct i2c_driver *driver;
+ const struct dev_pm_ops *pm = dev->driver ? dev->driver->pm : NULL;
- if (!client || !dev->driver)
+ if (pm_runtime_suspended(dev))
return 0;
- driver = to_i2c_driver(dev->driver);
- if (!driver->resume)
+
+ if (pm)
+ return pm->thaw ? pm->thaw(dev) : 0;
+
+ return i2c_legacy_resume(dev);
+}
+
+static int i2c_device_pm_poweroff(struct device *dev)
+{
+ const struct dev_pm_ops *pm = dev->driver ? dev->driver->pm : NULL;
+
+ if (pm_runtime_suspended(dev))
return 0;
- return driver->resume(client);
+
+ if (pm)
+ return pm->poweroff ? pm->poweroff(dev) : 0;
+
+ return i2c_legacy_suspend(dev, PMSG_HIBERNATE);
+}
+
+static int i2c_device_pm_restore(struct device *dev)
+{
+ const struct dev_pm_ops *pm = dev->driver ? dev->driver->pm : NULL;
+ int ret;
+
+ if (pm)
+ ret = pm->restore ? pm->restore(dev) : 0;
+ else
+ ret = i2c_legacy_resume(dev);
+
+ if (!ret) {
+ pm_runtime_disable(dev);
+ pm_runtime_set_active(dev);
+ pm_runtime_enable(dev);
+ }
+
+ return ret;
}
+#else /* !CONFIG_PM_SLEEP */
+#define i2c_device_pm_suspend NULL
+#define i2c_device_pm_resume NULL
+#define i2c_device_pm_freeze NULL
+#define i2c_device_pm_thaw NULL
+#define i2c_device_pm_poweroff NULL
+#define i2c_device_pm_restore NULL
+#endif /* !CONFIG_PM_SLEEP */
static void i2c_client_dev_release(struct device *dev)
{
@@ -298,9 +325,15 @@ static const struct attribute_group *i2c_dev_attr_groups[] = {
static const struct dev_pm_ops i2c_device_pm_ops = {
.suspend = i2c_device_pm_suspend,
.resume = i2c_device_pm_resume,
- .runtime_suspend = i2c_device_runtime_suspend,
- .runtime_resume = i2c_device_runtime_resume,
- .runtime_idle = i2c_device_runtime_idle,
+ .freeze = i2c_device_pm_freeze,
+ .thaw = i2c_device_pm_thaw,
+ .poweroff = i2c_device_pm_poweroff,
+ .restore = i2c_device_pm_restore,
+ SET_RUNTIME_PM_OPS(
+ pm_generic_runtime_suspend,
+ pm_generic_runtime_resume,
+ pm_generic_runtime_idle
+ )
};
struct bus_type i2c_bus_type = {
@@ -309,8 +342,6 @@ struct bus_type i2c_bus_type = {
.probe = i2c_device_probe,
.remove = i2c_device_remove,
.shutdown = i2c_device_shutdown,
- .suspend = i2c_device_suspend,
- .resume = i2c_device_resume,
.pm = &i2c_device_pm_ops,
};
EXPORT_SYMBOL_GPL(i2c_bus_type);
@@ -541,9 +572,9 @@ i2c_sysfs_new_device(struct device *dev, struct device_attribute *attr,
return -EEXIST;
/* Keep track of the added device */
- mutex_lock(&core_lock);
- list_add_tail(&client->detected, &userspace_devices);
- mutex_unlock(&core_lock);
+ i2c_lock_adapter(adap);
+ list_add_tail(&client->detected, &adap->userspace_clients);
+ i2c_unlock_adapter(adap);
dev_info(dev, "%s: Instantiated device %s at 0x%02hx\n", "new_device",
info.type, info.addr);
@@ -582,9 +613,10 @@ i2c_sysfs_delete_device(struct device *dev, struct device_attribute *attr,
/* Make sure the device was added through sysfs */
res = -ENOENT;
- mutex_lock(&core_lock);
- list_for_each_entry_safe(client, next, &userspace_devices, detected) {
- if (client->addr == addr && client->adapter == adap) {
+ i2c_lock_adapter(adap);
+ list_for_each_entry_safe(client, next, &adap->userspace_clients,
+ detected) {
+ if (client->addr == addr) {
dev_info(dev, "%s: Deleting device %s at 0x%02hx\n",
"delete_device", client->name, client->addr);
@@ -594,7 +626,7 @@ i2c_sysfs_delete_device(struct device *dev, struct device_attribute *attr,
break;
}
}
- mutex_unlock(&core_lock);
+ i2c_unlock_adapter(adap);
if (res < 0)
dev_err(dev, "%s: Can't find device in list\n",
@@ -676,6 +708,7 @@ static int i2c_register_adapter(struct i2c_adapter *adap)
}
rt_mutex_init(&adap->bus_lock);
+ INIT_LIST_HEAD(&adap->userspace_clients);
/* Set default timeout to 1 second if not already set */
if (adap->timeout == 0)
@@ -878,14 +911,15 @@ int i2c_del_adapter(struct i2c_adapter *adap)
return res;
/* Remove devices instantiated from sysfs */
- list_for_each_entry_safe(client, next, &userspace_devices, detected) {
- if (client->adapter == adap) {
- dev_dbg(&adap->dev, "Removing %s at 0x%x\n",
- client->name, client->addr);
- list_del(&client->detected);
- i2c_unregister_device(client);
- }
+ i2c_lock_adapter(adap);
+ list_for_each_entry_safe(client, next, &adap->userspace_clients,
+ detected) {
+ dev_dbg(&adap->dev, "Removing %s at 0x%x\n", client->name,
+ client->addr);
+ list_del(&client->detected);
+ i2c_unregister_device(client);
}
+ i2c_unlock_adapter(adap);
/* Detach any active clients. This can't fail, thus we do not
checking the returned value. */
@@ -1190,10 +1224,10 @@ EXPORT_SYMBOL(i2c_transfer);
*
* Returns negative errno, or else the number of bytes written.
*/
-int i2c_master_send(struct i2c_client *client,const char *buf ,int count)
+int i2c_master_send(struct i2c_client *client, const char *buf, int count)
{
int ret;
- struct i2c_adapter *adap=client->adapter;
+ struct i2c_adapter *adap = client->adapter;
struct i2c_msg msg;
msg.addr = client->addr;
@@ -1217,9 +1251,9 @@ EXPORT_SYMBOL(i2c_master_send);
*
* Returns negative errno, or else the number of bytes read.
*/
-int i2c_master_recv(struct i2c_client *client, char *buf ,int count)
+int i2c_master_recv(struct i2c_client *client, char *buf, int count)
{
- struct i2c_adapter *adap=client->adapter;
+ struct i2c_adapter *adap = client->adapter;
struct i2c_msg msg;
int ret;
@@ -1263,12 +1297,23 @@ static int i2c_detect_address(struct i2c_client *temp_client,
return 0;
/* Make sure there is something at this address */
- if (i2c_smbus_xfer(adapter, addr, 0, 0, 0, I2C_SMBUS_QUICK, NULL) < 0)
- return 0;
+ if (addr == 0x73 && (adapter->class & I2C_CLASS_HWMON)) {
+ /* Special probe for FSC hwmon chips */
+ union i2c_smbus_data dummy;
- /* Prevent 24RF08 corruption */
- if ((addr & ~0x0f) == 0x50)
- i2c_smbus_xfer(adapter, addr, 0, 0, 0, I2C_SMBUS_QUICK, NULL);
+ if (i2c_smbus_xfer(adapter, addr, 0, I2C_SMBUS_READ, 0,
+ I2C_SMBUS_BYTE_DATA, &dummy) < 0)
+ return 0;
+ } else {
+ if (i2c_smbus_xfer(adapter, addr, 0, I2C_SMBUS_WRITE, 0,
+ I2C_SMBUS_QUICK, NULL) < 0)
+ return 0;
+
+ /* Prevent 24RF08 corruption */
+ if ((addr & ~0x0f) == 0x50)
+ i2c_smbus_xfer(adapter, addr, 0, I2C_SMBUS_WRITE, 0,
+ I2C_SMBUS_QUICK, NULL);
+ }
/* Finally call the custom detection function */
memset(&info, 0, sizeof(struct i2c_board_info));
@@ -1410,7 +1455,7 @@ i2c_new_probed_device(struct i2c_adapter *adap,
}
EXPORT_SYMBOL_GPL(i2c_new_probed_device);
-struct i2c_adapter* i2c_get_adapter(int id)
+struct i2c_adapter *i2c_get_adapter(int id)
{
struct i2c_adapter *adapter;
@@ -1437,7 +1482,7 @@ static u8 crc8(u16 data)
{
int i;
- for(i = 0; i < 8; i++) {
+ for (i = 0; i < 8; i++) {
if (data & 0x8000)
data = data ^ POLY;
data = data << 1;
@@ -1450,7 +1495,7 @@ static u8 i2c_smbus_pec(u8 crc, u8 *p, size_t count)
{
int i;
- for(i = 0; i < count; i++)
+ for (i = 0; i < count; i++)
crc = crc8((crc ^ p[i]) << 8);
return crc;
}
@@ -1520,7 +1565,7 @@ EXPORT_SYMBOL(i2c_smbus_read_byte);
*/
s32 i2c_smbus_write_byte(struct i2c_client *client, u8 value)
{
- return i2c_smbus_xfer(client->adapter,client->addr,client->flags,
+ return i2c_smbus_xfer(client->adapter, client->addr, client->flags,
I2C_SMBUS_WRITE, value, I2C_SMBUS_BYTE, NULL);
}
EXPORT_SYMBOL(i2c_smbus_write_byte);
@@ -1558,9 +1603,9 @@ s32 i2c_smbus_write_byte_data(struct i2c_client *client, u8 command, u8 value)
{
union i2c_smbus_data data;
data.byte = value;
- return i2c_smbus_xfer(client->adapter,client->addr,client->flags,
- I2C_SMBUS_WRITE,command,
- I2C_SMBUS_BYTE_DATA,&data);
+ return i2c_smbus_xfer(client->adapter, client->addr, client->flags,
+ I2C_SMBUS_WRITE, command,
+ I2C_SMBUS_BYTE_DATA, &data);
}
EXPORT_SYMBOL(i2c_smbus_write_byte_data);
@@ -1597,9 +1642,9 @@ s32 i2c_smbus_write_word_data(struct i2c_client *client, u8 command, u16 value)
{
union i2c_smbus_data data;
data.word = value;
- return i2c_smbus_xfer(client->adapter,client->addr,client->flags,
- I2C_SMBUS_WRITE,command,
- I2C_SMBUS_WORD_DATA,&data);
+ return i2c_smbus_xfer(client->adapter, client->addr, client->flags,
+ I2C_SMBUS_WRITE, command,
+ I2C_SMBUS_WORD_DATA, &data);
}
EXPORT_SYMBOL(i2c_smbus_write_word_data);
@@ -1676,9 +1721,9 @@ s32 i2c_smbus_write_block_data(struct i2c_client *client, u8 command,
length = I2C_SMBUS_BLOCK_MAX;
data.block[0] = length;
memcpy(&data.block[1], values, length);
- return i2c_smbus_xfer(client->adapter,client->addr,client->flags,
- I2C_SMBUS_WRITE,command,
- I2C_SMBUS_BLOCK_DATA,&data);
+ return i2c_smbus_xfer(client->adapter, client->addr, client->flags,
+ I2C_SMBUS_WRITE, command,
+ I2C_SMBUS_BLOCK_DATA, &data);
}
EXPORT_SYMBOL(i2c_smbus_write_block_data);
@@ -1720,10 +1765,10 @@ EXPORT_SYMBOL(i2c_smbus_write_i2c_block_data);
/* Simulate a SMBus command using the i2c protocol
No checking of parameters is done! */
-static s32 i2c_smbus_xfer_emulated(struct i2c_adapter * adapter, u16 addr,
- unsigned short flags,
- char read_write, u8 command, int size,
- union i2c_smbus_data * data)
+static s32 i2c_smbus_xfer_emulated(struct i2c_adapter *adapter, u16 addr,
+ unsigned short flags,
+ char read_write, u8 command, int size,
+ union i2c_smbus_data *data)
{
/* So we need to generate a series of msgs. In the case of writing, we
need to use only one message; when reading, we need two. We initialize
@@ -1731,7 +1776,7 @@ static s32 i2c_smbus_xfer_emulated(struct i2c_adapter * adapter, u16 addr,
simpler. */
unsigned char msgbuf0[I2C_SMBUS_BLOCK_MAX+3];
unsigned char msgbuf1[I2C_SMBUS_BLOCK_MAX+2];
- int num = read_write == I2C_SMBUS_READ?2:1;
+ int num = read_write == I2C_SMBUS_READ ? 2 : 1;
struct i2c_msg msg[2] = { { addr, flags, 1, msgbuf0 },
{ addr, flags | I2C_M_RD, 0, msgbuf1 }
};
@@ -1740,7 +1785,7 @@ static s32 i2c_smbus_xfer_emulated(struct i2c_adapter * adapter, u16 addr,
int status;
msgbuf0[0] = command;
- switch(size) {
+ switch (size) {
case I2C_SMBUS_QUICK:
msg[0].len = 0;
/* Special case: The read/write field is used as data */
@@ -1767,7 +1812,7 @@ static s32 i2c_smbus_xfer_emulated(struct i2c_adapter * adapter, u16 addr,
if (read_write == I2C_SMBUS_READ)
msg[1].len = 2;
else {
- msg[0].len=3;
+ msg[0].len = 3;
msgbuf0[1] = data->word & 0xff;
msgbuf0[2] = data->word >> 8;
}
@@ -1860,26 +1905,26 @@ static s32 i2c_smbus_xfer_emulated(struct i2c_adapter * adapter, u16 addr,
}
if (read_write == I2C_SMBUS_READ)
- switch(size) {
- case I2C_SMBUS_BYTE:
- data->byte = msgbuf0[0];
- break;
- case I2C_SMBUS_BYTE_DATA:
- data->byte = msgbuf1[0];
- break;
- case I2C_SMBUS_WORD_DATA:
- case I2C_SMBUS_PROC_CALL:
- data->word = msgbuf1[0] | (msgbuf1[1] << 8);
- break;
- case I2C_SMBUS_I2C_BLOCK_DATA:
- for (i = 0; i < data->block[0]; i++)
- data->block[i+1] = msgbuf1[i];
- break;
- case I2C_SMBUS_BLOCK_DATA:
- case I2C_SMBUS_BLOCK_PROC_CALL:
- for (i = 0; i < msgbuf1[0] + 1; i++)
- data->block[i] = msgbuf1[i];
- break;
+ switch (size) {
+ case I2C_SMBUS_BYTE:
+ data->byte = msgbuf0[0];
+ break;
+ case I2C_SMBUS_BYTE_DATA:
+ data->byte = msgbuf1[0];
+ break;
+ case I2C_SMBUS_WORD_DATA:
+ case I2C_SMBUS_PROC_CALL:
+ data->word = msgbuf1[0] | (msgbuf1[1] << 8);
+ break;
+ case I2C_SMBUS_I2C_BLOCK_DATA:
+ for (i = 0; i < data->block[0]; i++)
+ data->block[i+1] = msgbuf1[i];
+ break;
+ case I2C_SMBUS_BLOCK_DATA:
+ case I2C_SMBUS_BLOCK_PROC_CALL:
+ for (i = 0; i < msgbuf1[0] + 1; i++)
+ data->block[i] = msgbuf1[i];
+ break;
}
return 0;
}
@@ -1924,7 +1969,7 @@ s32 i2c_smbus_xfer(struct i2c_adapter *adapter, u16 addr, unsigned short flags,
}
rt_mutex_unlock(&adapter->bus_lock);
} else
- res = i2c_smbus_xfer_emulated(adapter,addr,flags,read_write,
+ res = i2c_smbus_xfer_emulated(adapter, addr, flags, read_write,
command, protocol, data);
return res;