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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.c95
1 files changed, 56 insertions, 39 deletions
diff --git a/drivers/i2c/i2c-core.c b/drivers/i2c/i2c-core.c
index 7ca81f42d14b..b05378a3d673 100644
--- a/drivers/i2c/i2c-core.c
+++ b/drivers/i2c/i2c-core.c
@@ -95,16 +95,32 @@ struct device_driver i2c_adapter_driver = {
.bus = &i2c_bus_type,
};
+/* ------------------------------------------------------------------------- */
+
+/* I2C bus adapters -- one roots each I2C or SMBUS segment */
+
static void i2c_adapter_class_dev_release(struct class_device *dev)
{
struct i2c_adapter *adap = class_dev_to_i2c_adapter(dev);
complete(&adap->class_dev_released);
}
+static ssize_t i2c_adapter_show_name(struct class_device *cdev, char *buf)
+{
+ struct i2c_adapter *adap = class_dev_to_i2c_adapter(cdev);
+ return sprintf(buf, "%s\n", adap->name);
+}
+
+static struct class_device_attribute i2c_adapter_attrs[] = {
+ __ATTR(name, S_IRUGO, i2c_adapter_show_name, NULL),
+ { },
+};
+
struct class i2c_adapter_class = {
- .owner = THIS_MODULE,
- .name = "i2c-adapter",
- .release = &i2c_adapter_class_dev_release,
+ .owner = THIS_MODULE,
+ .name = "i2c-adapter",
+ .class_dev_attrs = i2c_adapter_attrs,
+ .release = &i2c_adapter_class_dev_release,
};
static ssize_t show_adapter_name(struct device *dev, struct device_attribute *attr, char *buf)
@@ -127,20 +143,17 @@ 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
+ * ---------------------------------------------------
*/
/* -----
@@ -178,8 +191,12 @@ int i2c_add_adapter(struct i2c_adapter *adap)
* If the parent pointer is not set up,
* we add this adapter to the host bus.
*/
- if (adap->dev.parent == NULL)
+ if (adap->dev.parent == NULL) {
adap->dev.parent = &platform_bus;
+ printk(KERN_WARNING "**WARNING** I2C adapter driver [%s] "
+ "forgot to specify physical device; fix it!\n",
+ adap->name);
+ }
sprintf(adap->dev.bus_id, "i2c-%d", adap->nr);
adap->dev.driver = &i2c_adapter_driver;
adap->dev.release = &i2c_adapter_dev_release;
@@ -314,7 +331,7 @@ 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);
@@ -338,13 +355,13 @@ 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) {
@@ -419,14 +436,14 @@ int i2c_attach_client(struct i2c_client *client)
goto out_unlock;
}
list_add_tail(&client->list,&adapter->clients);
-
+
client->usage_count = 0;
client->dev.parent = &client->adapter->dev;
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",
@@ -467,7 +484,7 @@ 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);
@@ -535,10 +552,10 @@ int i2c_release_client(struct i2c_client *client)
__FUNCTION__);
return -EPERM;
}
-
+
client->usage_count--;
i2c_dec_use_client(client);
-
+
return 0;
}
@@ -603,7 +620,7 @@ 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);
@@ -624,7 +641,7 @@ 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
@@ -757,7 +774,7 @@ 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");
@@ -817,7 +834,7 @@ 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))
@@ -834,14 +851,14 @@ 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;
}
@@ -891,13 +908,13 @@ 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)
@@ -996,11 +1013,11 @@ 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
@@ -1010,7 +1027,7 @@ 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;
@@ -1103,14 +1120,14 @@ 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)
@@ -1130,7 +1147,7 @@ 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;
@@ -1146,7 +1163,7 @@ 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;