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authorLinus Torvalds <torvalds@linux-foundation.org>2008-10-14 23:53:02 (GMT)
committerLinus Torvalds <torvalds@linux-foundation.org>2008-10-14 23:53:02 (GMT)
commit278429cff8809958d25415ba0ed32b59866ab1a8 (patch)
tree1085100d82525ff7c0fc93fad475e4320f293548 /drivers/i2c/i2c-core.c
parente413b210c541acac1a194085627db28a122f3bdf (diff)
parenta05f2c5a2735ee1d68770137fbbfc334d3b9cda9 (diff)
downloadlinux-fsl-qoriq-278429cff8809958d25415ba0ed32b59866ab1a8.tar.xz
Merge branch 'i2c-for-linus' of git://jdelvare.pck.nerim.net/jdelvare-2.6
* 'i2c-for-linus' of git://jdelvare.pck.nerim.net/jdelvare-2.6: i2c-viapro: Add support for SMBus Process Call transactions i2c: Restore i2c_smbus_process_call function i2c: Do earlier driver model init i2c: Only build Tyan SMBus mux drivers on x86 i2c: Guard against oopses from bad init sequences i2c: Document the implementation details of the /dev interface i2c: Improve dev-interface documentation i2c-parport-light: Don't register a platform device resource hwmon: (dme1737) Convert to a new-style i2c driver hwmon: (dme1737) Be less i2c-centric i2c/tps65010: Vibrator hookup to gpiolib i2c-viapro: Add VX800/VX820 support i2c: Renesas Highlander FPGA SMBus support i2c-pca-isa: Don't grab arbitrary resources i2c/isp1301_omap: Convert to a new-style i2c driver, part 2 i2c/isp1301_omap: Convert to a new-style i2c driver, part 1
Diffstat (limited to 'drivers/i2c/i2c-core.c')
-rw-r--r--drivers/i2c/i2c-core.c35
1 files changed, 34 insertions, 1 deletions
diff --git a/drivers/i2c/i2c-core.c b/drivers/i2c/i2c-core.c
index b346a68..42e852d 100644
--- a/drivers/i2c/i2c-core.c
+++ b/drivers/i2c/i2c-core.c
@@ -437,6 +437,10 @@ static int i2c_register_adapter(struct i2c_adapter *adap)
{
int res = 0, dummy;
+ /* Can't register until after driver model init */
+ if (unlikely(WARN_ON(!i2c_bus_type.p)))
+ return -EAGAIN;
+
mutex_init(&adap->bus_lock);
mutex_init(&adap->clist_lock);
INIT_LIST_HEAD(&adap->clients);
@@ -696,6 +700,10 @@ int i2c_register_driver(struct module *owner, struct i2c_driver *driver)
{
int res;
+ /* Can't register until after driver model init */
+ if (unlikely(WARN_ON(!i2c_bus_type.p)))
+ return -EAGAIN;
+
/* new style driver methods can't mix with legacy ones */
if (is_newstyle_driver(driver)) {
if (driver->attach_adapter || driver->detach_adapter
@@ -978,7 +986,10 @@ static void __exit i2c_exit(void)
bus_unregister(&i2c_bus_type);
}
-subsys_initcall(i2c_init);
+/* We must initialize early, because some subsystems register i2c drivers
+ * in subsys_initcall() code, but are linked (and initialized) before i2c.
+ */
+postcore_initcall(i2c_init);
module_exit(i2c_exit);
/* ----------------------------------------------------
@@ -1677,6 +1688,28 @@ s32 i2c_smbus_write_word_data(struct i2c_client *client, u8 command, u16 value)
EXPORT_SYMBOL(i2c_smbus_write_word_data);
/**
+ * i2c_smbus_process_call - SMBus "process call" protocol
+ * @client: Handle to slave device
+ * @command: Byte interpreted by slave
+ * @value: 16-bit "word" being written
+ *
+ * This executes the SMBus "process call" protocol, returning negative errno
+ * else a 16-bit unsigned "word" received from the device.
+ */
+s32 i2c_smbus_process_call(struct i2c_client *client, u8 command, u16 value)
+{
+ union i2c_smbus_data data;
+ int status;
+ data.word = value;
+
+ status = i2c_smbus_xfer(client->adapter, client->addr, client->flags,
+ I2C_SMBUS_WRITE, command,
+ I2C_SMBUS_PROC_CALL, &data);
+ return (status < 0) ? status : data.word;
+}
+EXPORT_SYMBOL(i2c_smbus_process_call);
+
+/**
* i2c_smbus_read_block_data - SMBus "block read" protocol
* @client: Handle to slave device
* @command: Byte interpreted by slave