fedora core 6 1.2949 + vserver 2.2.0
[linux-2.6.git] / drivers / i2c / i2c-core.c
index 62d7c7b..b05378a 100644 (file)
 #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 */
@@ -94,16 +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)
@@ -126,20 +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
+ * ---------------------------------------------------
  */
 
 /* -----
@@ -153,7 +167,7 @@ int i2c_add_adapter(struct i2c_adapter *adap)
        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;
@@ -168,8 +182,8 @@ int i2c_add_adapter(struct i2c_adapter *adap)
        }
 
        adap->nr =  id & MAX_ID_MASK;
-       init_MUTEX(&adap->bus_lock);
-       init_MUTEX(&adap->clist_lock);
+       mutex_init(&adap->bus_lock);
+       mutex_init(&adap->clist_lock);
        list_add_tail(&adap->list,&adapters);
        INIT_LIST_HEAD(&adap->clients);
 
@@ -177,20 +191,30 @@ 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;
-       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);
 
@@ -203,8 +227,19 @@ int i2c_add_adapter(struct i2c_adapter *adap)
        }
 
 out_unlock:
-       up(&core_lists);
+       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;
 }
 
 
@@ -216,7 +251,7 @@ int i2c_del_adapter(struct i2c_adapter *adap)
        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) {
@@ -272,7 +307,7 @@ int i2c_del_adapter(struct i2c_adapter *adap)
        dev_dbg(&adap->dev, "adapter [%s] unregistered\n", adap->name);
 
  out_unlock:
-       up(&core_lists);
+       mutex_unlock(&core_lists);
        return res;
 }
 
@@ -287,9 +322,7 @@ 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);
+       int res;
 
        /* add the driver to the list of i2c drivers in the driver core */
        driver->driver.owner = owner;
@@ -297,8 +330,10 @@ int i2c_register_driver(struct module *owner, struct i2c_driver *driver)
 
        res = driver_register(&driver->driver);
        if (res)
-               goto out_unlock;
-       
+               return res;
+
+       mutex_lock(&core_lists);
+
        list_add_tail(&driver->list,&drivers);
        pr_debug("i2c-core: driver [%s] registered\n", driver->driver.name);
 
@@ -310,9 +345,8 @@ int i2c_register_driver(struct module *owner, struct i2c_driver *driver)
                }
        }
 
- out_unlock:
-       up(&core_lists);
-       return res;
+       mutex_unlock(&core_lists);
+       return 0;
 }
 EXPORT_SYMBOL(i2c_register_driver);
 
@@ -321,13 +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;
 
-       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 
+        * attached. If so, detach them to be able to kill the driver
         * afterwards.
         */
        list_for_each(item1,&adapters) {
@@ -363,7 +397,7 @@ int i2c_del_driver(struct i2c_driver *driver)
        pr_debug("i2c-core: driver [%s] unregistered\n", driver->driver.name);
 
  out_unlock:
-       up(&core_lists);
+       mutex_unlock(&core_lists);
        return 0;
 }
 
@@ -384,9 +418,9 @@ int i2c_check_addr(struct i2c_adapter *adapter, int addr)
 {
        int rval;
 
-       down(&adapter->clist_lock);
+       mutex_lock(&adapter->clist_lock);
        rval = __i2c_check_addr(adapter, addr);
-       up(&adapter->clist_lock);
+       mutex_unlock(&adapter->clist_lock);
 
        return rval;
 }
@@ -394,22 +428,14 @@ 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;
 
-       down(&adapter->clist_lock);
+       mutex_lock(&adapter->clist_lock);
        if (__i2c_check_addr(client->adapter, client->addr)) {
-               up(&adapter->clist_lock);
-               return -EBUSY;
+               res = -EBUSY;
+               goto out_unlock;
        }
        list_add_tail(&client->list,&adapter->clients);
-       up(&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 +443,40 @@ 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 +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);
@@ -450,12 +501,12 @@ int i2c_detach_client(struct i2c_client *client)
                }
        }
 
-       down(&adapter->clist_lock);
+       mutex_lock(&adapter->clist_lock);
        list_del(&client->list);
        init_completion(&client->released);
        device_remove_file(&client->dev, &dev_attr_client_name);
        device_unregister(&client->dev);
-       up(&adapter->clist_lock);
+       mutex_unlock(&adapter->clist_lock);
        wait_for_completion(&client->released);
 
  out:
@@ -501,10 +552,10 @@ int i2c_release_client(struct i2c_client *client)
                         __FUNCTION__);
                return -EPERM;
        }
-       
+
        client->usage_count--;
        i2c_dec_use_client(client);
-       
+
        return 0;
 }
 
@@ -513,19 +564,19 @@ void i2c_clients_command(struct i2c_adapter *adap, unsigned int cmd, void *arg)
        struct list_head  *item;
        struct i2c_client *client;
 
-       down(&adap->clist_lock);
+       mutex_lock(&adap->clist_lock);
        list_for_each(item,&adap->clients) {
                client = list_entry(item, struct i2c_client, list);
                if (!try_module_get(client->driver->driver.owner))
                        continue;
                if (NULL != client->driver->command) {
-                       up(&adap->clist_lock);
+                       mutex_unlock(&adap->clist_lock);
                        client->driver->command(client,cmd,arg);
-                       down(&adap->clist_lock);
+                       mutex_lock(&adap->clist_lock);
                }
                module_put(client->driver->driver.owner);
        }
-       up(&adap->clist_lock);
+       mutex_unlock(&adap->clist_lock);
 }
 
 static int __init i2c_init(void)
@@ -569,9 +620,9 @@ int i2c_transfer(struct i2c_adapter * adap, struct i2c_msg *msgs, int num)
                }
 #endif
 
-               down(&adap->bus_lock);
+               mutex_lock_nested(&adap->bus_lock, adap->level);
                ret = adap->algo->master_xfer(adap,msgs,num);
-               up(&adap->bus_lock);
+               mutex_unlock(&adap->bus_lock);
 
                return ret;
        } else {
@@ -590,7 +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
@@ -674,11 +725,16 @@ 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 +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");
@@ -778,13 +834,13 @@ int i2c_probe(struct i2c_adapter *adapter,
 struct i2c_adapter* i2c_get_adapter(int id)
 {
        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;
 }
 
@@ -795,14 +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;
        }
@@ -852,13 +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)
@@ -868,7 +924,7 @@ 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 +940,7 @@ 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 +959,7 @@ 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)
@@ -916,15 +972,14 @@ s32 i2c_smbus_write_word_data(struct i2c_client *client, u8 command, u16 value)
 }
 
 s32 i2c_smbus_write_block_data(struct i2c_client *client, u8 command,
-                              u8 length, u8 *values)
+                              u8 length, const u8 *values)
 {
        union i2c_smbus_data data;
-       int i;
+
        if (length > I2C_SMBUS_BLOCK_MAX)
                length = I2C_SMBUS_BLOCK_MAX;
-       for (i = 1; i <= length; i++)
-               data.block[i] = values[i-1];
        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);
@@ -934,20 +989,18 @@ s32 i2c_smbus_write_block_data(struct i2c_client *client, u8 command,
 s32 i2c_smbus_read_i2c_block_data(struct i2c_client *client, u8 command, u8 *values)
 {
        union i2c_smbus_data data;
-       int i;
+
        if (i2c_smbus_xfer(client->adapter,client->addr,client->flags,
                              I2C_SMBUS_READ,command,
                              I2C_SMBUS_I2C_BLOCK_DATA,&data))
                return -1;
-       else {
-               for (i = 1; i <= data.block[0]; i++)
-                       values[i-1] = data.block[i];
-               return data.block[0];
-       }
+
+       memcpy(values, &data.block[1], data.block[0]);
+       return data.block[0];
 }
 
 s32 i2c_smbus_write_i2c_block_data(struct i2c_client *client, u8 command,
-                                  u8 length, u8 *values)
+                                  u8 length, const u8 *values)
 {
        union i2c_smbus_data data;
 
@@ -960,11 +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
@@ -974,7 +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;
@@ -1009,7 +1062,7 @@ 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:
@@ -1018,7 +1071,7 @@ 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) {
@@ -1067,14 +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)
@@ -1094,7 +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;
@@ -1110,7 +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;
@@ -1118,10 +1171,10 @@ s32 i2c_smbus_xfer(struct i2c_adapter * adapter, u16 addr, unsigned short flags,
        flags &= I2C_M_TEN | I2C_CLIENT_PEC;
 
        if (adapter->algo->smbus_xfer) {
-               down(&adapter->bus_lock);
+               mutex_lock(&adapter->bus_lock);
                res = adapter->algo->smbus_xfer(adapter,addr,flags,read_write,
                                                command,size,data);
-               up(&adapter->bus_lock);
+               mutex_unlock(&adapter->bus_lock);
        } else
                res = i2c_smbus_xfer_emulated(adapter,addr,flags,read_write,
                                              command,size,data);