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-rw-r--r--Documentation/i2c/busses/i2c-i8101
-rw-r--r--Documentation/i2c/busses/i2c-viapro27
-rw-r--r--Documentation/i2c/chips/x120538
-rw-r--r--Documentation/i2c/functionality7
-rw-r--r--Documentation/i2c/porting-clients2
-rw-r--r--Documentation/i2c/writing-clients27
6 files changed, 68 insertions, 34 deletions
diff --git a/Documentation/i2c/busses/i2c-i810 b/Documentation/i2c/busses/i2c-i810
index 0544eb332887..83c3b9743c3c 100644
--- a/Documentation/i2c/busses/i2c-i810
+++ b/Documentation/i2c/busses/i2c-i810
@@ -2,6 +2,7 @@ Kernel driver i2c-i810
Supported adapters:
* Intel 82810, 82810-DC100, 82810E, and 82815 (GMCH)
+ * Intel 82845G (GMCH)
Authors:
Frodo Looijaard <frodol@dds.nl>,
diff --git a/Documentation/i2c/busses/i2c-viapro b/Documentation/i2c/busses/i2c-viapro
index 702f5ac68c09..9363b8bd6109 100644
--- a/Documentation/i2c/busses/i2c-viapro
+++ b/Documentation/i2c/busses/i2c-viapro
@@ -4,17 +4,18 @@ Supported adapters:
* VIA Technologies, Inc. VT82C596A/B
Datasheet: Sometimes available at the VIA website
- * VIA Technologies, Inc. VT82C686A/B
+ * VIA Technologies, Inc. VT82C686A/B
Datasheet: Sometimes available at the VIA website
* VIA Technologies, Inc. VT8231, VT8233, VT8233A, VT8235, VT8237
Datasheet: available on request from Via
Authors:
- Frodo Looijaard <frodol@dds.nl>,
- Philip Edelbrock <phil@netroedge.com>,
- Kyösti Mälkki <kmalkki@cc.hut.fi>,
- Mark D. Studebaker <mdsxyz123@yahoo.com>
+ Frodo Looijaard <frodol@dds.nl>,
+ Philip Edelbrock <phil@netroedge.com>,
+ Kyösti Mälkki <kmalkki@cc.hut.fi>,
+ Mark D. Studebaker <mdsxyz123@yahoo.com>,
+ Jean Delvare <khali@linux-fr.org>
Module Parameters
-----------------
@@ -28,20 +29,22 @@ Description
-----------
i2c-viapro is a true SMBus host driver for motherboards with one of the
-supported VIA southbridges.
+supported VIA south bridges.
Your lspci -n listing must show one of these :
- device 1106:3050 (VT82C596 function 3)
- device 1106:3051 (VT82C596 function 3)
+ device 1106:3050 (VT82C596A function 3)
+ device 1106:3051 (VT82C596B function 3)
device 1106:3057 (VT82C686 function 4)
device 1106:3074 (VT8233)
device 1106:3147 (VT8233A)
- device 1106:8235 (VT8231)
- devide 1106:3177 (VT8235)
- devide 1106:3227 (VT8237)
+ device 1106:8235 (VT8231 function 4)
+ device 1106:3177 (VT8235)
+ device 1106:3227 (VT8237R)
If none of these show up, you should look in the BIOS for settings like
enable ACPI / SMBus or even USB.
-
+Except for the oldest chips (VT82C596A/B, VT82C686A and most probably
+VT8231), this driver supports I2C block transactions. Such transactions
+are mainly useful to read from and write to EEPROMs.
diff --git a/Documentation/i2c/chips/x1205 b/Documentation/i2c/chips/x1205
new file mode 100644
index 000000000000..09407c991fe5
--- /dev/null
+++ b/Documentation/i2c/chips/x1205
@@ -0,0 +1,38 @@
+Kernel driver x1205
+===================
+
+Supported chips:
+ * Xicor X1205 RTC
+ Prefix: 'x1205'
+ Addresses scanned: none
+ Datasheet: http://www.intersil.com/cda/deviceinfo/0,1477,X1205,00.html
+
+Authors:
+ Karen Spearel <kas11@tampabay.rr.com>,
+ Alessandro Zummo <a.zummo@towertech.it>
+
+Description
+-----------
+
+This module aims to provide complete access to the Xicor X1205 RTC.
+Recently Xicor has merged with Intersil, but the chip is
+still sold under the Xicor brand.
+
+This chip is located at address 0x6f and uses a 2-byte register addressing.
+Two bytes need to be written to read a single register, while most
+other chips just require one and take the second one as the data
+to be written. To prevent corrupting unknown chips, the user must
+explicitely set the probe parameter.
+
+example:
+
+modprobe x1205 probe=0,0x6f
+
+The module supports one more option, hctosys, which is used to set the
+software clock from the x1205. On systems where the x1205 is the
+only hardware rtc, this parameter could be used to achieve a correct
+date/time earlier in the system boot sequence.
+
+example:
+
+modprobe x1205 probe=0,0x6f hctosys=1
diff --git a/Documentation/i2c/functionality b/Documentation/i2c/functionality
index 41ffefbdc60c..60cca249e452 100644
--- a/Documentation/i2c/functionality
+++ b/Documentation/i2c/functionality
@@ -17,9 +17,10 @@ For the most up-to-date list of functionality constants, please check
I2C_FUNC_I2C Plain i2c-level commands (Pure SMBus
adapters typically can not do these)
I2C_FUNC_10BIT_ADDR Handles the 10-bit address extensions
- I2C_FUNC_PROTOCOL_MANGLING Knows about the I2C_M_REV_DIR_ADDR,
- I2C_M_REV_DIR_ADDR and I2C_M_REV_DIR_NOSTART
- flags (which modify the i2c protocol!)
+ I2C_FUNC_PROTOCOL_MANGLING Knows about the I2C_M_IGNORE_NAK,
+ I2C_M_REV_DIR_ADDR, I2C_M_NOSTART and
+ I2C_M_NO_RD_ACK flags (which modify the
+ I2C protocol!)
I2C_FUNC_SMBUS_QUICK Handles the SMBus write_quick command
I2C_FUNC_SMBUS_READ_BYTE Handles the SMBus read_byte command
I2C_FUNC_SMBUS_WRITE_BYTE Handles the SMBus write_byte command
diff --git a/Documentation/i2c/porting-clients b/Documentation/i2c/porting-clients
index 4849dfd6961c..184fac2377aa 100644
--- a/Documentation/i2c/porting-clients
+++ b/Documentation/i2c/porting-clients
@@ -82,7 +82,7 @@ Technical changes:
exit and exit_free. For i2c+isa drivers, labels should be named
ERROR0, ERROR1 and ERROR2. Don't forget to properly set err before
jumping to error labels. By the way, labels should be left-aligned.
- Use memset to fill the client and data area with 0x00.
+ Use kzalloc instead of kmalloc.
Use i2c_set_clientdata to set the client data (as opposed to
a direct access to client->data).
Use strlcpy instead of strcpy to copy the client name.
diff --git a/Documentation/i2c/writing-clients b/Documentation/i2c/writing-clients
index 077275722a7c..e94d9c6cc522 100644
--- a/Documentation/i2c/writing-clients
+++ b/Documentation/i2c/writing-clients
@@ -33,8 +33,8 @@ static struct i2c_driver foo_driver = {
.command = &foo_command /* may be NULL */
}
-The name can be chosen freely, and may be upto 40 characters long. Please
-use something descriptive here.
+The name field must match the driver name, including the case. It must not
+contain spaces, and may be up to 31 characters long.
Don't worry about the flags field; just put I2C_DF_NOTIFY into it. This
means that your driver will be notified when new adapters are found.
@@ -43,9 +43,6 @@ This is almost always what you want.
All other fields are for call-back functions which will be explained
below.
-There use to be two additional fields in this structure, inc_use et dec_use,
-for module usage count, but these fields were obsoleted and removed.
-
Extra client data
=================
@@ -58,6 +55,7 @@ be very useful.
An example structure is below.
struct foo_data {
+ struct i2c_client client;
struct semaphore lock; /* For ISA access in `sensors' drivers. */
int sysctl_id; /* To keep the /proc directory entry for
`sensors' drivers. */
@@ -310,22 +308,15 @@ For now, you can ignore the `flags' parameter. It is there for future use.
client structure, even though we cannot fill it completely yet.
But it allows us to access several i2c functions safely */
- /* Note that we reserve some space for foo_data too. If you don't
- need it, remove it. We do it here to help to lessen memory
- fragmentation. */
- if (! (new_client = kmalloc(sizeof(struct i2c_client) +
- sizeof(struct foo_data),
- GFP_KERNEL))) {
+ if (!(data = kzalloc(sizeof(struct foo_data), GFP_KERNEL))) {
err = -ENOMEM;
goto ERROR0;
}
- /* This is tricky, but it will set the data to the right value. */
- client->data = new_client + 1;
- data = (struct foo_data *) (client->data);
+ new_client = &data->client;
+ i2c_set_clientdata(new_client, data);
new_client->addr = address;
- new_client->data = data;
new_client->adapter = adapter;
new_client->driver = &foo_driver;
new_client->flags = 0;
@@ -451,7 +442,7 @@ much simpler than the attachment code, fortunately!
release_region(client->addr,LM78_EXTENT);
/* HYBRID SENSORS CHIP ONLY END */
- kfree(client); /* Frees client data too, if allocated at the same time */
+ kfree(data);
return 0;
}
@@ -576,12 +567,12 @@ SMBus communication
extern s32 i2c_smbus_write_block_data(struct i2c_client * client,
u8 command, u8 length,
u8 *values);
+ extern s32 i2c_smbus_read_i2c_block_data(struct i2c_client * client,
+ u8 command, u8 *values);
These ones were removed in Linux 2.6.10 because they had no users, but could
be added back later if needed:
- extern s32 i2c_smbus_read_i2c_block_data(struct i2c_client * client,
- u8 command, u8 *values);
extern s32 i2c_smbus_read_block_data(struct i2c_client * client,
u8 command, u8 *values);
extern s32 i2c_smbus_write_i2c_block_data(struct i2c_client * client,
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