/* With some changes from Kyösti Mälkki <kmalkki@cc.hut.fi>.
All SMBus-related things are written by Frodo Looijaard <frodol@dds.nl>
- SMBus 2.0 support by Mark Studebaker <mdsxyz123@yahoo.com> */
+ SMBus 2.0 support by Mark Studebaker <mdsxyz123@yahoo.com> and
+ Jean Delvare <khali@linux-fr.org> */
#include <linux/module.h>
#include <linux/kernel.h>
#include <linux/init.h>
#include <linux/idr.h>
#include <linux/seq_file.h>
+#include <linux/platform_device.h>
+#include <linux/mutex.h>
#include <asm/uaccess.h>
static LIST_HEAD(adapters);
static LIST_HEAD(drivers);
-static DECLARE_MUTEX(core_lists);
+static DEFINE_MUTEX(core_lists);
static DEFINE_IDR(i2c_adapter_idr);
/* match always succeeds, as we want the probe() to tell if we really accept this match */
return rc;
}
-struct bus_type i2c_bus_type = {
- .name = "i2c",
- .match = i2c_device_match,
- .suspend = i2c_bus_suspend,
- .resume = i2c_bus_resume,
-};
-
static int i2c_device_probe(struct device *dev)
{
return -ENODEV;
return 0;
}
+struct bus_type i2c_bus_type = {
+ .name = "i2c",
+ .match = i2c_device_match,
+ .probe = i2c_device_probe,
+ .remove = i2c_device_remove,
+ .suspend = i2c_bus_suspend,
+ .resume = i2c_bus_resume,
+};
+
void i2c_adapter_dev_release(struct device *dev)
{
struct i2c_adapter *adap = dev_to_i2c_adapter(dev);
.owner = THIS_MODULE,
.name = "i2c_adapter",
.bus = &i2c_bus_type,
- .probe = i2c_device_probe,
- .remove = i2c_device_remove,
};
static void i2c_adapter_class_dev_release(struct class_device *dev)
struct list_head *item;
struct i2c_driver *driver;
- down(&core_lists);
+ mutex_lock(&core_lists);
if (idr_pre_get(&i2c_adapter_idr, GFP_KERNEL) == 0) {
res = -ENOMEM;
/* inform drivers of new adapters */
list_for_each(item,&drivers) {
driver = list_entry(item, struct i2c_driver, list);
- if (driver->flags & I2C_DF_NOTIFY)
+ if (driver->attach_adapter)
/* We ignore the return code; if it fails, too bad */
driver->attach_adapter(adap);
}
out_unlock:
- up(&core_lists);
+ mutex_unlock(&core_lists);
return res;
}
struct i2c_client *client;
int res = 0;
- down(&core_lists);
+ mutex_lock(&core_lists);
/* First make sure that this adapter was ever added */
list_for_each_entry(adap_from_list, &adapters, list) {
if (driver->detach_adapter)
if ((res = driver->detach_adapter(adap))) {
dev_err(&adap->dev, "detach_adapter failed "
- "for driver [%s]\n", driver->name);
+ "for driver [%s]\n",
+ driver->driver.name);
goto out_unlock;
}
}
list_for_each_safe(item, _n, &adap->clients) {
client = list_entry(item, struct i2c_client, list);
- /* detaching devices is unconditional of the set notify
- * flag, as _all_ clients that reside on the adapter
- * must be deleted, as this would cause invalid states.
- */
if ((res=client->driver->detach_client(client))) {
dev_err(&adap->dev, "detach_client failed for client "
"[%s] at address 0x%02x\n", client->name,
dev_dbg(&adap->dev, "adapter [%s] unregistered\n", adap->name);
out_unlock:
- up(&core_lists);
+ mutex_unlock(&core_lists);
return res;
}
* chips.
*/
-int i2c_add_driver(struct i2c_driver *driver)
+int i2c_register_driver(struct module *owner, struct i2c_driver *driver)
{
struct list_head *item;
struct i2c_adapter *adapter;
int res = 0;
- down(&core_lists);
+ mutex_lock(&core_lists);
/* add the driver to the list of i2c drivers in the driver core */
- driver->driver.owner = driver->owner;
- driver->driver.name = driver->name;
+ driver->driver.owner = owner;
driver->driver.bus = &i2c_bus_type;
- driver->driver.probe = i2c_device_probe;
- driver->driver.remove = i2c_device_remove;
res = driver_register(&driver->driver);
if (res)
goto out_unlock;
list_add_tail(&driver->list,&drivers);
- pr_debug("i2c-core: driver [%s] registered\n", driver->name);
+ pr_debug("i2c-core: driver [%s] registered\n", driver->driver.name);
/* now look for instances of driver on our adapters */
- if (driver->flags & I2C_DF_NOTIFY) {
+ if (driver->attach_adapter) {
list_for_each(item,&adapters) {
adapter = list_entry(item, struct i2c_adapter, list);
driver->attach_adapter(adapter);
}
out_unlock:
- up(&core_lists);
+ mutex_unlock(&core_lists);
return res;
}
+EXPORT_SYMBOL(i2c_register_driver);
int i2c_del_driver(struct i2c_driver *driver)
{
int res = 0;
- down(&core_lists);
+ 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
* afterwards.
- *
- * Removing clients does not depend on the notify flag, else
- * invalid operation might (will!) result, when using stale client
- * pointers.
*/
list_for_each(item1,&adapters) {
adap = list_entry(item1, struct i2c_adapter, list);
if (driver->detach_adapter) {
if ((res = driver->detach_adapter(adap))) {
dev_err(&adap->dev, "detach_adapter failed "
- "for driver [%s]\n", driver->name);
+ "for driver [%s]\n",
+ driver->driver.name);
goto out_unlock;
}
} else {
driver_unregister(&driver->driver);
list_del(&driver->list);
- pr_debug("i2c-core: driver [%s] unregistered\n", driver->name);
+ pr_debug("i2c-core: driver [%s] unregistered\n", driver->driver.name);
out_unlock:
- up(&core_lists);
+ mutex_unlock(&core_lists);
return 0;
}
}
}
- if (client->flags & I2C_CLIENT_ALLOW_USE)
- client->usage_count = 0;
+ client->usage_count = 0;
client->dev.parent = &client->adapter->dev;
client->dev.driver = &client->driver->driver;
struct i2c_adapter *adapter = client->adapter;
int res = 0;
- if ((client->flags & I2C_CLIENT_ALLOW_USE)
- && (client->usage_count > 0)) {
+ if (client->usage_count > 0) {
dev_warn(&client->dev, "Client [%s] still busy, "
"can't detach\n", client->name);
return -EBUSY;
static int i2c_inc_use_client(struct i2c_client *client)
{
- if (!try_module_get(client->driver->owner))
+ if (!try_module_get(client->driver->driver.owner))
return -ENODEV;
if (!try_module_get(client->adapter->owner)) {
- module_put(client->driver->owner);
+ module_put(client->driver->driver.owner);
return -ENODEV;
}
static void i2c_dec_use_client(struct i2c_client *client)
{
- module_put(client->driver->owner);
+ module_put(client->driver->driver.owner);
module_put(client->adapter->owner);
}
if (ret)
return ret;
- if (client->flags & I2C_CLIENT_ALLOW_USE) {
- if (client->flags & I2C_CLIENT_ALLOW_MULTIPLE_USE)
- client->usage_count++;
- else if (client->usage_count > 0)
- goto busy;
- else
- client->usage_count++;
- }
+ client->usage_count++;
return 0;
- busy:
- i2c_dec_use_client(client);
- return -EBUSY;
}
int i2c_release_client(struct i2c_client *client)
{
- if(client->flags & I2C_CLIENT_ALLOW_USE) {
- if(client->usage_count>0)
- client->usage_count--;
- else {
- pr_debug("i2c-core: %s used one too many times\n",
- __FUNCTION__);
- return -EPERM;
- }
+ if (!client->usage_count) {
+ pr_debug("i2c-core: %s used one too many times\n",
+ __FUNCTION__);
+ return -EPERM;
}
+ client->usage_count--;
i2c_dec_use_client(client);
return 0;
down(&adap->clist_lock);
list_for_each(item,&adap->clients) {
client = list_entry(item, struct i2c_client, list);
- if (!try_module_get(client->driver->owner))
+ if (!try_module_get(client->driver->driver.owner))
continue;
if (NULL != client->driver->command) {
up(&adap->clist_lock);
client->driver->command(client,cmd,arg);
down(&adap->clist_lock);
}
- module_put(client->driver->owner);
+ module_put(client->driver->driver.owner);
}
up(&adap->clist_lock);
}
{
struct i2c_adapter *adapter;
- down(&core_lists);
+ mutex_lock(&core_lists);
adapter = (struct i2c_adapter *)idr_find(&i2c_adapter_idr, id);
if (adapter && !try_module_get(adapter->owner))
adapter = NULL;
- up(&core_lists);
+ mutex_unlock(&core_lists);
return adapter;
}
return (u8)(data >> 8);
}
-/* CRC over count bytes in the first array plus the bytes in the rest
- array if it is non-null. rest[0] is the (length of rest) - 1
- and is included. */
-static u8 i2c_smbus_partial_pec(u8 crc, int count, u8 *first, u8 *rest)
+/* Incremental CRC8 over count bytes in the array pointed to by p */
+static u8 i2c_smbus_pec(u8 crc, u8 *p, size_t count)
{
int i;
for(i = 0; i < count; i++)
- crc = crc8((crc ^ first[i]) << 8);
- if(rest != NULL)
- for(i = 0; i <= rest[0]; i++)
- crc = crc8((crc ^ rest[i]) << 8);
+ crc = crc8((crc ^ p[i]) << 8);
return crc;
}
-static u8 i2c_smbus_pec(int count, u8 *first, u8 *rest)
+/* Assume a 7-bit address, which is reasonable for SMBus */
+static u8 i2c_smbus_msg_pec(u8 pec, struct i2c_msg *msg)
{
- return i2c_smbus_partial_pec(0, count, first, rest);
+ /* The address will be sent first */
+ u8 addr = (msg->addr << 1) | !!(msg->flags & I2C_M_RD);
+ pec = i2c_smbus_pec(pec, &addr, 1);
+
+ /* The data buffer follows */
+ return i2c_smbus_pec(pec, msg->buf, msg->len);
}
-/* Returns new "size" (transaction type)
- Note that we convert byte to byte_data and byte_data to word_data
- rather than invent new xxx_PEC transactions. */
-static int i2c_smbus_add_pec(u16 addr, u8 command, int size,
- union i2c_smbus_data *data)
+/* Used for write only transactions */
+static inline void i2c_smbus_add_pec(struct i2c_msg *msg)
{
- u8 buf[3];
-
- buf[0] = addr << 1;
- buf[1] = command;
- switch(size) {
- case I2C_SMBUS_BYTE:
- data->byte = i2c_smbus_pec(2, buf, NULL);
- size = I2C_SMBUS_BYTE_DATA;
- break;
- case I2C_SMBUS_BYTE_DATA:
- buf[2] = data->byte;
- data->word = buf[2] |
- (i2c_smbus_pec(3, buf, NULL) << 8);
- size = I2C_SMBUS_WORD_DATA;
- break;
- case I2C_SMBUS_WORD_DATA:
- /* unsupported */
- break;
- case I2C_SMBUS_BLOCK_DATA:
- data->block[data->block[0] + 1] =
- i2c_smbus_pec(2, buf, data->block);
- size = I2C_SMBUS_BLOCK_DATA_PEC;
- break;
- }
- return size;
+ msg->buf[msg->len] = i2c_smbus_msg_pec(0, msg);
+ msg->len++;
}
-static int i2c_smbus_check_pec(u16 addr, u8 command, int size, u8 partial,
- union i2c_smbus_data *data)
+/* Return <0 on CRC error
+ If there was a write before this read (most cases) we need to take the
+ partial CRC from the write part into account.
+ Note that this function does modify the message (we need to decrease the
+ message length to hide the CRC byte from the caller). */
+static int i2c_smbus_check_pec(u8 cpec, struct i2c_msg *msg)
{
- u8 buf[3], rpec, cpec;
+ u8 rpec = msg->buf[--msg->len];
+ cpec = i2c_smbus_msg_pec(cpec, msg);
- buf[1] = command;
- switch(size) {
- case I2C_SMBUS_BYTE_DATA:
- buf[0] = (addr << 1) | 1;
- cpec = i2c_smbus_pec(2, buf, NULL);
- rpec = data->byte;
- break;
- case I2C_SMBUS_WORD_DATA:
- buf[0] = (addr << 1) | 1;
- buf[2] = data->word & 0xff;
- cpec = i2c_smbus_pec(3, buf, NULL);
- rpec = data->word >> 8;
- break;
- case I2C_SMBUS_WORD_DATA_PEC:
- /* unsupported */
- cpec = rpec = 0;
- break;
- case I2C_SMBUS_PROC_CALL_PEC:
- /* unsupported */
- cpec = rpec = 0;
- break;
- case I2C_SMBUS_BLOCK_DATA_PEC:
- buf[0] = (addr << 1);
- buf[2] = (addr << 1) | 1;
- cpec = i2c_smbus_pec(3, buf, data->block);
- rpec = data->block[data->block[0] + 1];
- break;
- case I2C_SMBUS_BLOCK_PROC_CALL_PEC:
- buf[0] = (addr << 1) | 1;
- rpec = i2c_smbus_partial_pec(partial, 1,
- buf, data->block);
- cpec = data->block[data->block[0] + 1];
- break;
- default:
- cpec = rpec = 0;
- break;
- }
if (rpec != cpec) {
pr_debug("i2c-core: Bad PEC 0x%02x vs. 0x%02x\n",
rpec, cpec);
s32 i2c_smbus_write_byte(struct i2c_client *client, u8 value)
{
- union i2c_smbus_data data; /* only for PEC */
return i2c_smbus_xfer(client->adapter,client->addr,client->flags,
- I2C_SMBUS_WRITE,value, I2C_SMBUS_BYTE,&data);
+ I2C_SMBUS_WRITE, value, I2C_SMBUS_BYTE, NULL);
}
s32 i2c_smbus_read_byte_data(struct i2c_client *client, u8 command)
}
}
+s32 i2c_smbus_write_i2c_block_data(struct i2c_client *client, u8 command,
+ u8 length, u8 *values)
+{
+ union i2c_smbus_data data;
+
+ if (length > I2C_SMBUS_BLOCK_MAX)
+ 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_I2C_BLOCK_DATA, &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,
{ addr, flags | I2C_M_RD, 0, msgbuf1 }
};
int i;
+ u8 partial_pec = 0;
msgbuf0[0] = command;
switch(size) {
msgbuf0[2] = (data->word >> 8) & 0xff;
break;
case I2C_SMBUS_BLOCK_DATA:
- case I2C_SMBUS_BLOCK_DATA_PEC:
if (read_write == I2C_SMBUS_READ) {
dev_err(&adapter->dev, "Block read not supported "
"under I2C emulation!\n");
data->block[0]);
return -1;
}
- if(size == I2C_SMBUS_BLOCK_DATA_PEC)
- (msg[0].len)++;
for (i = 1; i < msg[0].len; i++)
msgbuf0[i] = data->block[i-1];
}
break;
case I2C_SMBUS_BLOCK_PROC_CALL:
- case I2C_SMBUS_BLOCK_PROC_CALL_PEC:
dev_dbg(&adapter->dev, "Block process call not supported "
"under I2C emulation!\n");
return -1;
return -1;
}
+ i = ((flags & I2C_CLIENT_PEC) && size != I2C_SMBUS_QUICK
+ && size != I2C_SMBUS_I2C_BLOCK_DATA);
+ if (i) {
+ /* Compute PEC if first message is a write */
+ if (!(msg[0].flags & I2C_M_RD)) {
+ 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++;
+ }
+
if (i2c_transfer(adapter, msg, num) < 0)
return -1;
+ /* Check PEC if last message is a read */
+ if (i && (msg[num-1].flags & I2C_M_RD)) {
+ if (i2c_smbus_check_pec(partial_pec, &msg[num-1]) < 0)
+ return -1;
+ }
+
if (read_write == I2C_SMBUS_READ)
switch(size) {
case I2C_SMBUS_BYTE:
union i2c_smbus_data * data)
{
s32 res;
- int swpec = 0;
- u8 partial = 0;
flags &= I2C_M_TEN | I2C_CLIENT_PEC;
- if((flags & I2C_CLIENT_PEC) &&
- !(i2c_check_functionality(adapter, I2C_FUNC_SMBUS_HWPEC_CALC))) {
- swpec = 1;
- if(read_write == I2C_SMBUS_READ &&
- size == I2C_SMBUS_BLOCK_DATA)
- size = I2C_SMBUS_BLOCK_DATA_PEC;
- else if(size == I2C_SMBUS_PROC_CALL)
- size = I2C_SMBUS_PROC_CALL_PEC;
- else if(size == I2C_SMBUS_BLOCK_PROC_CALL) {
- i2c_smbus_add_pec(addr, command,
- I2C_SMBUS_BLOCK_DATA, data);
- partial = data->block[data->block[0] + 1];
- size = I2C_SMBUS_BLOCK_PROC_CALL_PEC;
- } else if(read_write == I2C_SMBUS_WRITE &&
- size != I2C_SMBUS_QUICK &&
- size != I2C_SMBUS_I2C_BLOCK_DATA)
- size = i2c_smbus_add_pec(addr, command, size, data);
- }
if (adapter->algo->smbus_xfer) {
down(&adapter->bus_lock);
res = i2c_smbus_xfer_emulated(adapter,addr,flags,read_write,
command,size,data);
- if(res >= 0 && swpec &&
- size != I2C_SMBUS_QUICK && size != I2C_SMBUS_I2C_BLOCK_DATA &&
- (read_write == I2C_SMBUS_READ || size == I2C_SMBUS_PROC_CALL_PEC ||
- size == I2C_SMBUS_BLOCK_PROC_CALL_PEC)) {
- if(i2c_smbus_check_pec(addr, command, size, partial, data))
- return -1;
- }
return res;
}
EXPORT_SYMBOL(i2c_add_adapter);
EXPORT_SYMBOL(i2c_del_adapter);
-EXPORT_SYMBOL(i2c_add_driver);
EXPORT_SYMBOL(i2c_del_driver);
EXPORT_SYMBOL(i2c_attach_client);
EXPORT_SYMBOL(i2c_detach_client);
EXPORT_SYMBOL(i2c_smbus_write_word_data);
EXPORT_SYMBOL(i2c_smbus_write_block_data);
EXPORT_SYMBOL(i2c_smbus_read_i2c_block_data);
+EXPORT_SYMBOL(i2c_smbus_write_i2c_block_data);
MODULE_AUTHOR("Simon G. Vogl <simon@tk.uni-linz.ac.at>");
MODULE_DESCRIPTION("I2C-Bus main module");
git://ftp.safe.ca / safe / jmp / linux-2.6 / blobdiff