docs: i2c: smbus-protocol: mention the repeated start condition

[linux-2.6-microblaze.git] / Documentation / i2c / smbus-protocol.rst

diff --git a/Documentation/i2c/smbus-protocol.rst b/Documentation/i2c/smbus-protocol.rst
index 9e07e6b..00d8e17 100644 (file)
--- a/Documentation/i2c/smbus-protocol.rst
+++ b/Documentation/i2c/smbus-protocol.rst
@@ -36,6 +36,8 @@ Key to symbols
 
 =============== =============================================================
 S               Start condition
+Sr              Repeated start condition, used to switch from write to
+                read mode.
 P               Stop condition
 Rd/Wr (1 bit)   Read/Write bit. Rd equals 1, Wr equals 0.
 A, NA (1 bit)   Acknowledge (ACK) and Not Acknowledge (NACK) bit
@@ -100,7 +102,7 @@ Implemented by i2c_smbus_read_byte_data()
 This reads a single byte from a device, from a designated register.
 The register is specified through the Comm byte::
 
-  S Addr Wr [A] Comm [A] S Addr Rd [A] [Data] NA P
+  S Addr Wr [A] Comm [A] Sr Addr Rd [A] [Data] NA P
 
 Functionality flag: I2C_FUNC_SMBUS_READ_BYTE_DATA
 
@@ -114,7 +116,7 @@ This operation is very like Read Byte; again, data is read from a
 device, from a designated register that is specified through the Comm
 byte. But this time, the data is a complete word (16 bits)::
 
-  S Addr Wr [A] Comm [A] S Addr Rd [A] [DataLow] A [DataHigh] NA P
+  S Addr Wr [A] Comm [A] Sr Addr Rd [A] [DataLow] A [DataHigh] NA P
 
 Functionality flag: I2C_FUNC_SMBUS_READ_WORD_DATA
 
@@ -164,7 +166,7 @@ This command selects a device register (through the Comm byte), sends
 16 bits of data to it, and reads 16 bits of data in return::
 
   S Addr Wr [A] Comm [A] DataLow [A] DataHigh [A]
-                               S Addr Rd [A] [DataLow] A [DataHigh] NA P
+                              Sr Addr Rd [A] [DataLow] A [DataHigh] NA P
 
 Functionality flag: I2C_FUNC_SMBUS_PROC_CALL
 
@@ -181,7 +183,7 @@ of data is specified by the device in the Count byte.
 ::
 
   S Addr Wr [A] Comm [A]
-             S Addr Rd [A] [Count] A [Data] A [Data] A ... A [Data] NA P
+            Sr Addr Rd [A] [Count] A [Data] A [Data] A ... A [Data] NA P
 
 Functionality flag: I2C_FUNC_SMBUS_READ_BLOCK_DATA
 
@@ -212,7 +214,7 @@ This command selects a device register (through the Comm byte), sends
 1 to 31 bytes of data to it, and reads 1 to 31 bytes of data in return::
 
   S Addr Wr [A] Comm [A] Count [A] Data [A] ...
-                               S Addr Rd [A] [Count] A [Data] ... A P
+                              Sr Addr Rd [A] [Count] A [Data] ... A P
 
 Functionality flag: I2C_FUNC_SMBUS_BLOCK_PROC_CALL
 
@@ -300,7 +302,7 @@ This command reads a block of bytes from a device, from a
 designated register that is specified through the Comm byte::
 
   S Addr Wr [A] Comm [A]
-             S Addr Rd [A] [Data] A [Data] A ... A [Data] NA P
+            Sr Addr Rd [A] [Data] A [Data] A ... A [Data] NA P
 
 Functionality flag: I2C_FUNC_SMBUS_READ_I2C_BLOCK