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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.c152
1 files changed, 94 insertions, 58 deletions
diff --git a/drivers/i2c/i2c-core.c b/drivers/i2c/i2c-core.c
index 9cb277d6aa4..3e31f1d265c 100644
--- a/drivers/i2c/i2c-core.c
+++ b/drivers/i2c/i2c-core.c
@@ -127,20 +127,17 @@ static ssize_t show_client_name(struct device *dev, struct device_attribute *att
return sprintf(buf, "%s\n", client->name);
}
-/*
- * We can't use the DEVICE_ATTR() macro here as we want the same filename for a
- * different type of a device. So beware if the DEVICE_ATTR() macro ever
- * changes, this definition will also have to change.
+/*
+ * We can't use the DEVICE_ATTR() macro here, as we used the same name for
+ * an i2c adapter attribute (above).
*/
-static struct device_attribute dev_attr_client_name = {
- .attr = {.name = "name", .mode = S_IRUGO, .owner = THIS_MODULE },
- .show = &show_client_name,
-};
+static struct device_attribute dev_attr_client_name =
+ __ATTR(name, S_IRUGO, &show_client_name, NULL);
/* ---------------------------------------------------
- * registering functions
- * ---------------------------------------------------
+ * registering functions
+ * ---------------------------------------------------
*/
/* -----
@@ -183,15 +180,21 @@ int i2c_add_adapter(struct i2c_adapter *adap)
sprintf(adap->dev.bus_id, "i2c-%d", adap->nr);
adap->dev.driver = &i2c_adapter_driver;
adap->dev.release = &i2c_adapter_dev_release;
- device_register(&adap->dev);
- device_create_file(&adap->dev, &dev_attr_name);
+ res = device_register(&adap->dev);
+ if (res)
+ goto out_list;
+ res = device_create_file(&adap->dev, &dev_attr_name);
+ if (res)
+ goto out_unregister;
/* Add this adapter to the i2c_adapter class */
memset(&adap->class_dev, 0x00, sizeof(struct class_device));
adap->class_dev.dev = &adap->dev;
adap->class_dev.class = &i2c_adapter_class;
strlcpy(adap->class_dev.class_id, adap->dev.bus_id, BUS_ID_SIZE);
- class_device_register(&adap->class_dev);
+ res = class_device_register(&adap->class_dev);
+ if (res)
+ goto out_remove_name;
dev_dbg(&adap->dev, "adapter [%s] registered\n", adap->name);
@@ -206,6 +209,17 @@ int i2c_add_adapter(struct i2c_adapter *adap)
out_unlock:
mutex_unlock(&core_lists);
return res;
+
+out_remove_name:
+ device_remove_file(&adap->dev, &dev_attr_name);
+out_unregister:
+ init_completion(&adap->dev_released); /* Needed? */
+ device_unregister(&adap->dev);
+ wait_for_completion(&adap->dev_released);
+out_list:
+ list_del(&adap->list);
+ idr_remove(&i2c_adapter_idr, adap->nr);
+ goto out_unlock;
}
@@ -297,7 +311,7 @@ int i2c_register_driver(struct module *owner, struct i2c_driver *driver)
res = driver_register(&driver->driver);
if (res)
return res;
-
+
mutex_lock(&core_lists);
list_add_tail(&driver->list,&drivers);
@@ -321,13 +335,13 @@ int i2c_del_driver(struct i2c_driver *driver)
struct list_head *item1, *item2, *_n;
struct i2c_client *client;
struct i2c_adapter *adap;
-
+
int res = 0;
mutex_lock(&core_lists);
/* Have a look at each adapter, if clients of this driver are still
- * attached. If so, detach them to be able to kill the driver
+ * attached. If so, detach them to be able to kill the driver
* afterwards.
*/
list_for_each(item1,&adapters) {
@@ -394,22 +408,14 @@ int i2c_check_addr(struct i2c_adapter *adapter, int addr)
int i2c_attach_client(struct i2c_client *client)
{
struct i2c_adapter *adapter = client->adapter;
+ int res = 0;
mutex_lock(&adapter->clist_lock);
if (__i2c_check_addr(client->adapter, client->addr)) {
- mutex_unlock(&adapter->clist_lock);
- return -EBUSY;
+ res = -EBUSY;
+ goto out_unlock;
}
list_add_tail(&client->list,&adapter->clients);
- mutex_unlock(&adapter->clist_lock);
-
- if (adapter->client_register) {
- if (adapter->client_register(client)) {
- dev_dbg(&adapter->dev, "client_register "
- "failed for client [%s] at 0x%02x\n",
- client->name, client->addr);
- }
- }
client->usage_count = 0;
@@ -417,15 +423,40 @@ int i2c_attach_client(struct i2c_client *client)
client->dev.driver = &client->driver->driver;
client->dev.bus = &i2c_bus_type;
client->dev.release = &i2c_client_release;
-
+
snprintf(&client->dev.bus_id[0], sizeof(client->dev.bus_id),
"%d-%04x", i2c_adapter_id(adapter), client->addr);
dev_dbg(&adapter->dev, "client [%s] registered with bus id %s\n",
client->name, client->dev.bus_id);
- device_register(&client->dev);
- device_create_file(&client->dev, &dev_attr_client_name);
-
+ res = device_register(&client->dev);
+ if (res)
+ goto out_list;
+ res = device_create_file(&client->dev, &dev_attr_client_name);
+ if (res)
+ goto out_unregister;
+ mutex_unlock(&adapter->clist_lock);
+
+ if (adapter->client_register) {
+ if (adapter->client_register(client)) {
+ dev_dbg(&adapter->dev, "client_register "
+ "failed for client [%s] at 0x%02x\n",
+ client->name, client->addr);
+ }
+ }
+
return 0;
+
+out_unregister:
+ init_completion(&client->released); /* Needed? */
+ device_unregister(&client->dev);
+ wait_for_completion(&client->released);
+out_list:
+ list_del(&client->list);
+ dev_err(&adapter->dev, "Failed to attach i2c client %s at 0x%02x "
+ "(%d)\n", client->name, client->addr, res);
+out_unlock:
+ mutex_unlock(&adapter->clist_lock);
+ return res;
}
@@ -433,7 +464,7 @@ int i2c_detach_client(struct i2c_client *client)
{
struct i2c_adapter *adapter = client->adapter;
int res = 0;
-
+
if (client->usage_count > 0) {
dev_warn(&client->dev, "Client [%s] still busy, "
"can't detach\n", client->name);
@@ -501,10 +532,10 @@ int i2c_release_client(struct i2c_client *client)
__FUNCTION__);
return -EPERM;
}
-
+
client->usage_count--;
i2c_dec_use_client(client);
-
+
return 0;
}
@@ -569,7 +600,7 @@ int i2c_transfer(struct i2c_adapter * adap, struct i2c_msg *msgs, int num)
}
#endif
- mutex_lock(&adap->bus_lock);
+ mutex_lock_nested(&adap->bus_lock, adap->level);
ret = adap->algo->master_xfer(adap,msgs,num);
mutex_unlock(&adap->bus_lock);
@@ -590,7 +621,7 @@ int i2c_master_send(struct i2c_client *client,const char *buf ,int count)
msg.flags = client->flags & I2C_M_TEN;
msg.len = count;
msg.buf = (char *)buf;
-
+
ret = i2c_transfer(adap, &msg, 1);
/* If everything went ok (i.e. 1 msg transmitted), return #bytes
@@ -674,11 +705,16 @@ static int i2c_probe_address(struct i2c_adapter *adapter, int addr, int kind,
/* Finally call the custom detection function */
err = found_proc(adapter, addr, kind);
-
/* -ENODEV can be returned if there is a chip at the given address
but it isn't supported by this chip driver. We catch it here as
this isn't an error. */
- return (err == -ENODEV) ? 0 : err;
+ if (err == -ENODEV)
+ err = 0;
+
+ if (err)
+ dev_warn(&adapter->dev, "Client creation failed at 0x%x (%d)\n",
+ addr, err);
+ return err;
}
int i2c_probe(struct i2c_adapter *adapter,
@@ -718,7 +754,7 @@ int i2c_probe(struct i2c_adapter *adapter,
if (!i2c_check_functionality(adapter, I2C_FUNC_SMBUS_QUICK)) {
if (address_data->probe[0] == I2C_CLIENT_END
&& address_data->normal_i2c[0] == I2C_CLIENT_END)
- return 0;
+ return 0;
dev_warn(&adapter->dev, "SMBus Quick command not supported, "
"can't probe for chips\n");
@@ -778,7 +814,7 @@ int i2c_probe(struct i2c_adapter *adapter,
struct i2c_adapter* i2c_get_adapter(int id)
{
struct i2c_adapter *adapter;
-
+
mutex_lock(&core_lists);
adapter = (struct i2c_adapter *)idr_find(&i2c_adapter_idr, id);
if (adapter && !try_module_get(adapter->owner))
@@ -795,14 +831,14 @@ void i2c_put_adapter(struct i2c_adapter *adap)
/* The SMBus parts */
-#define POLY (0x1070U << 3)
+#define POLY (0x1070U << 3)
static u8
crc8(u16 data)
{
int i;
-
+
for(i = 0; i < 8; i++) {
- if (data & 0x8000)
+ if (data & 0x8000)
data = data ^ POLY;
data = data << 1;
}
@@ -852,13 +888,13 @@ static int i2c_smbus_check_pec(u8 cpec, struct i2c_msg *msg)
rpec, cpec);
return -1;
}
- return 0;
+ return 0;
}
s32 i2c_smbus_write_quick(struct i2c_client *client, u8 value)
{
return i2c_smbus_xfer(client->adapter,client->addr,client->flags,
- value,0,I2C_SMBUS_QUICK,NULL);
+ value,0,I2C_SMBUS_QUICK,NULL);
}
s32 i2c_smbus_read_byte(struct i2c_client *client)
@@ -868,7 +904,7 @@ s32 i2c_smbus_read_byte(struct i2c_client *client)
I2C_SMBUS_READ,0,I2C_SMBUS_BYTE, &data))
return -1;
else
- return 0x0FF & data.byte;
+ return data.byte;
}
s32 i2c_smbus_write_byte(struct i2c_client *client, u8 value)
@@ -884,7 +920,7 @@ s32 i2c_smbus_read_byte_data(struct i2c_client *client, u8 command)
I2C_SMBUS_READ,command, I2C_SMBUS_BYTE_DATA,&data))
return -1;
else
- return 0x0FF & data.byte;
+ return data.byte;
}
s32 i2c_smbus_write_byte_data(struct i2c_client *client, u8 command, u8 value)
@@ -903,7 +939,7 @@ s32 i2c_smbus_read_word_data(struct i2c_client *client, u8 command)
I2C_SMBUS_READ,command, I2C_SMBUS_WORD_DATA, &data))
return -1;
else
- return 0x0FFFF & data.word;
+ return data.word;
}
s32 i2c_smbus_write_word_data(struct i2c_client *client, u8 command, u16 value)
@@ -957,11 +993,11 @@ s32 i2c_smbus_write_i2c_block_data(struct i2c_client *client, u8 command,
I2C_SMBUS_I2C_BLOCK_DATA, &data);
}
-/* Simulate a SMBus command using the i2c protocol
+/* 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,
+static s32 i2c_smbus_xfer_emulated(struct i2c_adapter * adapter, u16 addr,
unsigned short flags,
- char read_write, u8 command, int size,
+ 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
@@ -971,7 +1007,7 @@ static s32 i2c_smbus_xfer_emulated(struct i2c_adapter * adapter, u16 addr,
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;
- struct i2c_msg msg[2] = { { addr, flags, 1, msgbuf0 },
+ struct i2c_msg msg[2] = { { addr, flags, 1, msgbuf0 },
{ addr, flags | I2C_M_RD, 0, msgbuf1 }
};
int i;
@@ -1006,7 +1042,7 @@ static s32 i2c_smbus_xfer_emulated(struct i2c_adapter * adapter, u16 addr,
else {
msg[0].len=3;
msgbuf0[1] = data->word & 0xff;
- msgbuf0[2] = (data->word >> 8) & 0xff;
+ msgbuf0[2] = data->word >> 8;
}
break;
case I2C_SMBUS_PROC_CALL:
@@ -1015,7 +1051,7 @@ static s32 i2c_smbus_xfer_emulated(struct i2c_adapter * adapter, u16 addr,
msg[0].len = 3;
msg[1].len = 2;
msgbuf0[1] = data->word & 0xff;
- msgbuf0[2] = (data->word >> 8) & 0xff;
+ msgbuf0[2] = data->word >> 8;
break;
case I2C_SMBUS_BLOCK_DATA:
if (read_write == I2C_SMBUS_READ) {
@@ -1064,14 +1100,14 @@ static s32 i2c_smbus_xfer_emulated(struct i2c_adapter * adapter, u16 addr,
if (i) {
/* Compute PEC if first message is a write */
if (!(msg[0].flags & I2C_M_RD)) {
- if (num == 1) /* Write only */
+ if (num == 1) /* Write only */
i2c_smbus_add_pec(&msg[0]);
else /* Write followed by read */
partial_pec = i2c_smbus_msg_pec(0, &msg[0]);
}
/* Ask for PEC if last message is a read */
if (msg[num-1].flags & I2C_M_RD)
- msg[num-1].len++;
+ msg[num-1].len++;
}
if (i2c_transfer(adapter, msg, num) < 0)
@@ -1091,7 +1127,7 @@ static s32 i2c_smbus_xfer_emulated(struct i2c_adapter * adapter, u16 addr,
case I2C_SMBUS_BYTE_DATA:
data->byte = msgbuf1[0];
break;
- case I2C_SMBUS_WORD_DATA:
+ case I2C_SMBUS_WORD_DATA:
case I2C_SMBUS_PROC_CALL:
data->word = msgbuf1[0] | (msgbuf1[1] << 8);
break;
@@ -1107,7 +1143,7 @@ static s32 i2c_smbus_xfer_emulated(struct i2c_adapter * adapter, u16 addr,
s32 i2c_smbus_xfer(struct i2c_adapter * adapter, u16 addr, unsigned short flags,
- char read_write, u8 command, int size,
+ char read_write, u8 command, int size,
union i2c_smbus_data * data)
{
s32 res;